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Sample records for brain structure due

  1. Validity of semi-quantitative scale for brain MRI in unilateral cerebral palsy due to periventricular white matter lesions: Relationship with hand sensorimotor function and structural connectivity

    Directory of Open Access Journals (Sweden)

    Simona Fiori

    2015-01-01

    Conclusion: The sqMRI scale demonstrates first evidence of construct validity against impaired motor and sensory function measures and brain structural connectivity in a cohort of children with UCP due to PWM lesions. More severe lesions correlated with poorer paretic hand sensorimotor function and impaired structural connectivity in the hemisphere contralateral to the clinical side of hemiplegia. The quantitative structural MRI scoring may be a useful clinical tool for studying brain structure–function relationships but requires further validation in other populations of CP.

  2. Assessment of the structural brain network reveals altered connectivity in children with unilateral cerebral palsy due to periventricular white matter lesions

    Directory of Open Access Journals (Sweden)

    Kerstin Pannek

    2014-01-01

    Conclusion: This study shows that network-based analysis of structural connectivity can identify alterations in FA in unilateral CP, and that these alterations in FA are related to clinical function. Application of this connectome-based analysis to investigate alterations in connectivity following treatment may elucidate the neurological correlates of improved functioning due to intervention.

  3. [Unusual location of a brain abscess due to Listeria monocytogenes].

    Science.gov (United States)

    Coste, J-F; Duval, V; Nguyen, Y; Guillard, T; Brasme, L; David, C; Strady, C; Lecuit, M; de Champs, C

    2012-10-01

    Here we report a case of sustentorial brain abscess due to Listeria monocytogenes. Blood culture and procalcitonine blood measurement were negative. L. monocytogenes was isolated from CSF after inoculation in Castañeda medium. PMID:21835558

  4. Changes in brain gray matter due to repetitive painful stimulation.

    Science.gov (United States)

    Teutsch, S; Herken, W; Bingel, U; Schoell, E; May, A

    2008-08-15

    Using functional imaging, we recently investigated how repeated painful stimulation over several days is processed, perceived and modulated in the healthy human brain. Considering that activation-dependent brain plasticity in humans on a structural level has already been demonstrated in adults, we were interested in whether repeated painful stimulation may lead to structural changes of the brain. 14 healthy subjects were stimulated daily with a 20 min pain paradigm for 8 consecutive days, using structural MRI performed on days 1, 8, 22 and again after 1 year. Using voxel based morphometry, we are able to show that repeated painful stimulation resulted in a substantial increase of gray matter in pain transmitting areas, including mid-cingulate and somatosensory cortex. These changes are stimulation dependent, i.e. they recede after the regular nociceptive input is stopped. This data raises some interesting questions regarding structural plasticity of the brain concerning the experience of both acute and chronic pain. PMID:18582579

  5. Personality Change due to Traumatic Brain Injury in Children and Adolescents: Neurocognitive Correlates

    OpenAIRE

    Wilde, Elisabeth A.; Bigler, Erin D; Hanten, Gerri; Dennis, Maureen; Schachar, Russell J.; Saunders, Ann E.; Ewing-Cobbs, Linda; Chapman, Sandra B.; Wesley K. Thompson; Yang, Tony T.; Levin, Harvey S.

    2015-01-01

    Personality Change due to traumatic brain injury (PC) in children is an important psychiatric complication of injury and is a form of severe affective dysregulation. The aim of the study was to examine neurocognitive correlates of PC. The sample included children (n=177) aged 5-14 years with traumatic brain injury from consecutive admissions to 5 trauma centers were followed prospectively at baseline and 6 months with semi-structured psychiatric interviews. Injury severity, socioeconomic stat...

  6. MRI findings of brain damage due to neonatal hypoglycemia

    International Nuclear Information System (INIS)

    images. Conclusion: The findings suggest that posterior parieto-occipital regions are most frequently injured in neonatal period due to severe hypoglycemia. DWI is a useful technique in the early detection and evaluation of hypoglycemic brain injury of neonates. (authors)

  7. Socioeconomic Status and Structural Brain Development

    Directory of Open Access Journals (Sweden)

    Natalie H Brito

    2014-09-01

    Full Text Available Recent advances in neuroimaging methods have made accessible new ways of disentangling the complex interplay between genetic and environmental factors that influence structural brain development. In recent years, research investigating associations between socioeconomic status (SES and brain development have found significant links between SES and changes in brain structure, especially in areas related to memory, executive control and emotion. This review focuses on studies examining links between structural brain development and SES disparities of the magnitude typically found in developing countries. We highlight how highly correlated measures of SES are differentially related to structural changes within the brain.

  8. Socioeconomic status and structural brain development.

    Science.gov (United States)

    Brito, Natalie H; Noble, Kimberly G

    2014-01-01

    Recent advances in neuroimaging methods have made accessible new ways of disentangling the complex interplay between genetic and environmental factors that influence structural brain development. In recent years, research investigating associations between socioeconomic status (SES) and brain development have found significant links between SES and changes in brain structure, especially in areas related to memory, executive control, and emotion. This review focuses on studies examining links between structural brain development and SES disparities of the magnitude typically found in developing countries. We highlight how highly correlated measures of SES are differentially related to structural changes within the brain. PMID:25249931

  9. THE DEVELOPMENT OF BRAIN STRUCTURE AND CONNECTIVITY

    OpenAIRE

    Wierenga, L.M.

    2016-01-01

    The human brain undergoes profound structural changes with development. It does not mature by simply growing, rather the transition to adulthood is a dynamic process with regionally specific patterns. However, there is no consensus on the timing and shape of growth trajectories of brain structures. In this thesis we capitalize on advances in multimodal MRI and use longitudinal study designs to map structural brain maturation and connectivity in typical and atypical children and adolescents. O...

  10. Structural plasticity of the adult brain

    OpenAIRE

    Gage, Fred H.

    2004-01-01

    The adult brain has long been considered stable and unchanging, except for the inevitable decline that occurs with aqinq. This view is now being challenged with clear evidence that structural changes occur in the brain throughout life, including the generation of new neurons and other brain cells, and connections between and among neurons. What is as remarkable is that the changes that occur in the adult brain are influenced by the behaviors an individual engages in, as well as the environmen...

  11. Structural Graphical Lasso for Learning Mouse Brain Connectivity

    KAUST Repository

    Yang, Sen

    2015-01-01

    Investigations into brain connectivity aim to recover networks of brain regions connected by anatomical tracts or by functional associations. The inference of brain networks has recently attracted much interest due to the increasing availability of high-resolution brain imaging data. Sparse inverse covariance estimation with lasso and group lasso penalty has been demonstrated to be a powerful approach to discover brain networks. Motivated by the hierarchical structure of the brain networks, we consider the problem of estimating a graphical model with tree-structural regularization in this paper. The regularization encourages the graphical model to exhibit a brain-like structure. Specifically, in this hierarchical structure, hundreds of thousands of voxels serve as the leaf nodes of the tree. A node in the intermediate layer represents a region formed by voxels in the subtree rooted at that node. The whole brain is considered as the root of the tree. We propose to apply the tree-structural regularized graphical model to estimate the mouse brain network. However, the dimensionality of whole-brain data, usually on the order of hundreds of thousands, poses significant computational challenges. Efficient algorithms that are capable of estimating networks from high-dimensional data are highly desired. To address the computational challenge, we develop a screening rule which can quickly identify many zero blocks in the estimated graphical model, thereby dramatically reducing the computational cost of solving the proposed model. It is based on a novel insight on the relationship between screening and the so-called proximal operator that we first establish in this paper. We perform experiments on both synthetic data and real data from the Allen Developing Mouse Brain Atlas; results demonstrate the effectiveness and efficiency of the proposed approach.

  12. The domesticated brain: genetics of brain mass and brain structure in an avian species

    Science.gov (United States)

    Henriksen, R.; Johnsson, M.; Andersson, L.; Jensen, P.; Wright, D.

    2016-01-01

    As brain size usually increases with body size it has been assumed that the two are tightly constrained and evolutionary studies have therefore often been based on relative brain size (i.e. brain size proportional to body size) rather than absolute brain size. The process of domestication offers an excellent opportunity to disentangle the linkage between body and brain mass due to the extreme selection for increased body mass that has occurred. By breeding an intercross between domestic chicken and their wild progenitor, we address this relationship by simultaneously mapping the genes that control inter-population variation in brain mass and body mass. Loci controlling variation in brain mass and body mass have separate genetic architectures and are therefore not directly constrained. Genetic mapping of brain regions indicates that domestication has led to a larger body mass and to a lesser extent a larger absolute brain mass in chickens, mainly due to enlargement of the cerebellum. Domestication has traditionally been linked to brain mass regression, based on measurements of relative brain mass, which confounds the large body mass augmentation due to domestication. Our results refute this concept in the chicken. PMID:27687864

  13. Brain injuries due to neonatal hypoglycemia: case report

    International Nuclear Information System (INIS)

    Although hypoglycemia may be common among neonates, brain injuries resulting from isolated neonatal hypoglycemia are rare. The condition may cause neurological symptoms such as stupor, jitteriness, and seizures, though in their absence, diagnosis delayed or difficult. Hypoglycemia was diagnosed in a three-day-old neonate after he visited the emergency department with loose stool, poor oral intake, and decreased activity, first experienced two days earlier. Two days after his visity, several episodes of seizure occurred. T2 and diffusion-weighted magnetic resonance (MR) scanning, performed at 11 days of age, revealed bilateral and symmetrical high signal intensity lesions in occipital, parietal, and temporal lobes. We report the MR findings of hypoglycemic encephalopathy in a neonate

  14. Brain injuries due to neonatal hypoglycemia: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Bong; Song, Chang Joon; Chang, Mae Young; Youn, Hyae Won [College of Medicine, Chungram National Univ., Daejeon (Korea, Republic of)

    2003-10-01

    Although hypoglycemia may be common among neonates, brain injuries resulting from isolated neonatal hypoglycemia are rare. The condition may cause neurological symptoms such as stupor, jitteriness, and seizures, though in their absence, diagnosis delayed or difficult. Hypoglycemia was diagnosed in a three-day-old neonate after he visited the emergency department with loose stool, poor oral intake, and decreased activity, first experienced two days earlier. Two days after his visity, several episodes of seizure occurred. T2 and diffusion-weighted magnetic resonance (MR) scanning, performed at 11 days of age, revealed bilateral and symmetrical high signal intensity lesions in occipital, parietal, and temporal lobes. We report the MR findings of hypoglycemic encephalopathy in a neonate.

  15. Structural connectivity asymmetry in the neonatal brain.

    Science.gov (United States)

    Ratnarajah, Nagulan; Rifkin-Graboi, Anne; Fortier, Marielle V; Chong, Yap Seng; Kwek, Kenneth; Saw, Seang-Mei; Godfrey, Keith M; Gluckman, Peter D; Meaney, Michael J; Qiu, Anqi

    2013-07-15

    Asymmetry of the neonatal brain is not yet understood at the level of structural connectivity. We utilized DTI deterministic tractography and structural network analysis based on graph theory to determine the pattern of structural connectivity asymmetry in 124 normal neonates. We tracted white matter axonal pathways characterizing interregional connections among brain regions and inferred asymmetry in left and right anatomical network properties. Our findings revealed that in neonates, small-world characteristics were exhibited, but did not differ between the two hemispheres, suggesting that neighboring brain regions connect tightly with each other, and that one region is only a few paths away from any other region within each hemisphere. Moreover, the neonatal brain showed greater structural efficiency in the left hemisphere than that in the right. In neonates, brain regions involved in motor, language, and memory functions play crucial roles in efficient communication in the left hemisphere, while brain regions involved in emotional processes play crucial roles in efficient communication in the right hemisphere. These findings suggest that even at birth, the topology of each cerebral hemisphere is organized in an efficient and compact manner that maps onto asymmetric functional specializations seen in adults, implying lateralized brain functions in infancy. PMID:23501049

  16. Migraine and structural abnormalities in the brain

    DEFF Research Database (Denmark)

    Hougaard, Anders; Amin, Faisal Mohammad; Ashina, Messoud

    2014-01-01

    PURPOSE OF REVIEW: The aim is to provide an overview of recent studies of structural brain abnormalities in migraine and to discuss the potential clinical significance of their findings. RECENT FINDINGS: Brain structure continues to be a topic of extensive research in migraine. Despite advances...... in neuroimaging techniques, it is not yet clear if migraine is associated with grey matter changes. Recent large population-based studies sustain the notion of increased prevalence of white matter abnormalities in migraine, and possibly of silent infarct-like lesions. The clinical relevance of this association...... is not clear. Structural changes are not related to cognitive decline, but a link to an increased risk of stroke, especially in patients with aura, cannot be ruled out. SUMMARY: Migraine may be a risk factor for structural changes in the brain. It is not yet clear how factors such as migraine sub-type, attack...

  17. Electro-Acupuncture for Treatment of Dysequillibrium Due to Cerebellum or Brain Stem Infarction

    Institute of Scientific and Technical Information of China (English)

    赵宏; 刘志顺; 刘效娟

    2003-01-01

    @@ The authors treated 26 cases of dysequillibrium due tocerebellum or brain stem infarction byelectro-acupuncture from Aug 2000 - April 2002. Theresults were quite satisfactory and reported as follows.

  18. Brain ultrasonographic findings of late-onset circulatory dysfunction due to adrenal insufficiency in preterm infants

    OpenAIRE

    Su-Mi Shin; Jee Won Chai

    2016-01-01

    Purpose: The aim of this study was to characterize the brain ultrasonographic findings of late-onset circulatory dysfunction (LCD) due to adrenal insufficiency (AI) in preterm infants. Methods: Among the 257 preterm infants born at

  19. Migraine and structural changes in the brain

    DEFF Research Database (Denmark)

    Bashir, Asma; Lipton, Richard B; Ashina, Sait;

    2013-01-01

    To evaluate the association between migraine without aura (MO) and migraine with aura (MA) and 3 types of structural brain abnormalities detected by MRI: white matter abnormalities (WMAs), infarct-like lesions (ILLs), and volumetric changes in gray and white matter (GM, WM) regions....

  20. Visual hallucinations of autobiographic memory and asomatognosia: a case of epilepsy due to brain cysticercosis.

    Science.gov (United States)

    Orjuela-Rojas, Juan Manuel; Ramírez-Bermúdez, Jesús; Martínez-Juárez, Iris E; Kerik, Nora Estela; Diaz Meneses, Iván; Pérez-Gay, Fernanda Juárez

    2015-01-01

    The current study describes the case of a woman with symptomatic epilepsy due to brain cysticercosis acquired during childhood. During her adolescence, she developed seizures characterized by metamorphopsia, hallucinations of autobiographic memory and, finally, asomatognosia. Magnetic brain imaging showed a calcified lesion in the right occipitotemporal cortex, and positron emission tomography imaging confirmed the presence of interictal hypometabolism in two regions: the right parietal cortex and the right lateral and posterior temporal cortex. We discuss the link between these brain areas and the symptoms described under the concepts of epileptogenic lesion, epileptogenic zone, functional deficit zone, and symptomatogenic zone.

  1. The human brain. Prenatal development and structure

    Energy Technology Data Exchange (ETDEWEB)

    Marin-Padilla, Miguel

    2011-07-01

    This book is unique among the current literature in that it systematically documents the prenatal structural development of the human brain. It is based on lifelong study using essentially a single staining procedure, the classic rapid Golgi procedure, which ensures an unusual and desirable uniformity in the observations. The book is amply illustrated with 81 large, high-quality color photomicrographs never previously reproduced. These photomicrographs, obtained at 6, 7, 11, 15, 18, 20, 25, 30, 35, and 40 weeks of gestation, offer a fascinating insight into the sequential prenatal development of neurons, blood vessels, and glia in the human brain. (orig.)

  2. Deterioration of concrete structures in coastal environment due to carbonation.

    Science.gov (United States)

    Balaji, K V G D; Gopalaraju, S S S V; Trilochan, Jena

    2010-07-01

    Failure of existing concrete structures takes place due to lack of durability, and not due to less structural strength. One of the important aspects of durability is carbonation depth. The rate of carbonation in concrete is influenced by both its physical properties and exposure conditions. Rebar corrodes when carbonation reaches to a depth of concrete cover provided. In the present work, various concrete structures with different life periods and exposed to different weather conditions have been considered to study the carbonation effect. It is observed that the effect of carbonation is more in the structures located near to the sea coast and on windward face of the structure. PMID:21391402

  3. A Thoracic Mechanism of Mild Traumatic Brain Injury Due to Blast Pressure Waves

    CERN Document Server

    Courtney, Amy; 10.1016/j.mehy.2008.08.015

    2008-01-01

    The mechanisms by which blast pressure waves cause mild to moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast pressure wave reaches the brain via a thoracic mechanism is considered in light of ballistic and blast pressure wave research. Ballistic pressure waves, caused by penetrating ballistic projectiles or ballistic impacts to body armor, can only reach the brain via an internal mechanism and have been shown to cause cerebral effects. Similar effects have been documented when a blast pressure wave has been applied to the whole body or focused on the thorax in animal models. While vagotomy reduces apnea and bradycardia due to ballistic or blast pressure waves, it does not eliminate neural damage in the brain, suggesting that the pressure wave directly affects the brain cells via a thoracic mechanism. ...

  4. Statistical analysis of minimum cost path based structural brain connectivity

    NARCIS (Netherlands)

    De Boer, R.; Schaap, M.; Van der Lijn, F.; Vrooman, H.A.; De Groot, M.; Van der Lugt, A.; Ikram, M.A.; Vernooij, M.W.; Breteler, M.M.B.; Niessen, W.J.

    2010-01-01

    Diffusion MRI can be used to study the structural connectivity within the brain. Brain connectivity is often represented by a binary network whose topology can be studied using graph theory. We present a framework for the construction of weighted structural brain networks, containing information abo

  5. Comparing Structural Brain Connectivity by the Infinite Relational Model

    DEFF Research Database (Denmark)

    Ambrosen, Karen Marie Sandø; Herlau, Tue; Dyrby, Tim;

    2013-01-01

    The growing focus in neuroimaging on analyzing brain connectivity calls for powerful and reliable statistical modeling tools. We examine the Infinite Relational Model (IRM) as a tool to identify and compare structure in brain connectivity graphs by contrasting its performance on graphs from...... modeling tool for the identification of structure and quantification of similarity in graphs of brain connectivity in general....

  6. Structural brain lesions in inflammatory bowel disease

    Institute of Scientific and Technical Information of China (English)

    Can; Dolapcioglu; Hatice; Dolapcioglu

    2015-01-01

    Central nervous system(CNS) complications or manifes-tations of inflammatory bowel disease deserve particular attention because symptomatic conditions can require early diagnosis and treatment, whereas unexplained manifestations might be linked with pathogenic me-chanisms. This review focuses on both symptomatic and asymptomatic brain lesions detectable on imaging studies, as well as their frequency and potential mecha-nisms. A direct causal relationship between inflammatory bowel disease(IBD) and asymptomatic structural brain changes has not been demonstrated, but several possible explanations, including vasculitis, thromboembolism and malnutrition, have been proposed. IBD is associated with a tendency for thromboembolisms; therefore, cerebro-vascular thromboembolism represents the most frequent and grave CNS complication. Vasculitis, demyelinating conditions and CNS infections are among the other CNS manifestations of the disease. Biological agents also represent a risk factor, particularly for demyelination. Identification of the nature and potential mechanisms of brain lesions detectable on imaging studies would shed further light on the disease process and could improve patient care through early diagnosis and treatment.

  7. Structural covariance networks in the mouse brain.

    Science.gov (United States)

    Pagani, Marco; Bifone, Angelo; Gozzi, Alessandro

    2016-04-01

    The presence of networks of correlation between regional gray matter volume as measured across subjects in a group of individuals has been consistently described in several human studies, an approach termed structural covariance MRI (scMRI). Complementary to prevalent brain mapping modalities like functional and diffusion-weighted imaging, the approach can provide precious insights into the mutual influence of trophic and plastic processes in health and pathological states. To investigate whether analogous scMRI networks are present in lower mammal species amenable to genetic and experimental manipulation such as the laboratory mouse, we employed high resolution morphoanatomical MRI in a large cohort of genetically-homogeneous wild-type mice (C57Bl6/J) and mapped scMRI networks using a seed-based approach. We show that the mouse brain exhibits robust homotopic scMRI networks in both primary and associative cortices, a finding corroborated by independent component analyses of cortical volumes. Subcortical structures also showed highly symmetric inter-hemispheric correlations, with evidence of distributed antero-posterior networks in diencephalic regions of the thalamus and hypothalamus. Hierarchical cluster analysis revealed six identifiable clusters of cortical and sub-cortical regions corresponding to previously described neuroanatomical systems. Our work documents the presence of homotopic cortical and subcortical scMRI networks in the mouse brain, thus supporting the use of this species to investigate the elusive biological and neuroanatomical underpinnings of scMRI network development and its derangement in neuropathological states. The identification of scMRI networks in genetically homogeneous inbred mice is consistent with the emerging view of a key role of environmental factors in shaping these correlational networks.

  8. Brain ultrasonographic findings of late-onset circulatory dysfunction due to adrenal insufficiency in preterm infants

    Science.gov (United States)

    2016-01-01

    Purpose: The aim of this study was to characterize the brain ultrasonographic findings of late-onset circulatory dysfunction (LCD) due to adrenal insufficiency (AI) in preterm infants. Methods: Among the 257 preterm infants born at AI. Brain ultrasonographic findings were retrospectively analyzed before and after LCD in 14 preterm infants, after exclusion of the other 21 infants with AI due to the following causes: death (n=2), early AI (n=5), sepsis (n=1), and patent ductus arteriosus (n=13). Results: Fourteen of 257 infants (5.4%) were diagnosed with LCD due to AI. The age at LCD was a median of 18.5 days (range, 9 to 32 days). The last ultrasonographic findings before LCD occurred showed grade 1 periventricular echogenicity (PVE) in all 14 patients and germinal matrix hemorrhage (GMH) with focal cystic change in one patient. Ultrasonographic findings after LCD demonstrated no significant change in grade 1 PVE and no new lesions in eight (57%), grade 1 PVE with newly appearing GMH in three (21%), and increased PVE in three (21%) infants. Five infants (36%) showed new development (n=4) or increased size (n=1) of GMH. Two of three infants (14%) with increased PVE developed cystic periventricular leukomalacia (PVL) and rapid progression to macrocystic encephalomalacia. Conclusion: LCD due to AI may be associated with the late development of GMH, increased PVE after LCD, and cystic PVL with rapid progression to macrocystic encephalomalacia. PMID:27156563

  9. Personality Change Due to Traumatic Brain Injury in Children and Adolescents: Neurocognitive Correlates.

    Science.gov (United States)

    Max, Jeffrey E; Wilde, Elisabeth A; Bigler, Erin D; Hanten, Gerri; Dennis, Maureen; Schachar, Russell J; Saunders, Ann E; Ewing-Cobbs, Linda; Chapman, Sandra B; Thompson, Wesley K; Yang, Tony T; Levin, Harvey S

    2015-01-01

    Personality change due to traumatic brain injury (PC) in children is an important psychiatric complication of injury and is a form of severe affective dysregulation. This study aimed to examine neurocognitive correlates of PC. The sample included 177 children 5-14 years old with traumatic brain injury who were enrolled from consecutive admissions to five trauma centers. Patients were followed up prospectively at baseline and at 6 months, and they were assessed with semistructured psychiatric interviews. Injury severity, socioeconomic status, and neurocognitive function (measures of attention, processing speed, verbal memory, IQ, verbal working memory, executive function, naming/reading, expressive language, motor speed, and motor inhibition) were assessed with standardized instruments. Unremitted PC was present in 26 (18%) of 141 participants assessed at 6 months postinjury. Attention, processing speed, verbal memory, IQ, and executive function were significantly associated with PC even after socioeconomic status, injury severity, and preinjury attention deficit hyperactivity disorder were controlled. These findings are a first step in characterizing concomitant cognitive impairments associated with PC. The results have implications beyond brain injury to potentially elucidate the neurocognitive symptom complex associated with mood instability regardless of etiology.

  10. Thermodynamics of water structural reorganization due to geometric confinement

    Science.gov (United States)

    Stroberg, Wylie; Lichter, Seth

    2015-03-01

    Models of aqueous solvation have successfully quantified the behavior of water near convex bodies. However, many important processes occurring in aqueous solution involve interactions between solutes and surfaces with complicated non-convex geometries. Examples include the folding of proteins, hydrophobic association of solutes, ligand-receptor binding, and water confined within nanotubes and pores. For these geometries, models for solvation of convex bodies fail to account for the added interactions associated with structural confinement. Due to water's propensity to form networks of hydrogen bonds, small alterations to the confining geometry can induce large structural rearrangement within the water. We perform systematic Monte Carlo simulations of water confined to cylindrical cavities of varying aspect ratio to investigate how small geometric changes to the confining geometry may cause large changes to the structure and thermodynamic state of water. Using the Wang-Landau algorithm, we obtain free energies, enthalpies, entropies, and heat capacities across a broad range of temperatures, and show how these quantities are influenced by the structural rearrangement of water molecules due to geometric perturbations.

  11. The effects of physical activity on brain structure

    OpenAIRE

    AdamThomas; PeterABandettini

    2012-01-01

    Aerobic activity is a powerful stimulus for improving mental health and for generating structural changes in the brain. We review the literature documenting these structural changes and explore exactly where in the brain these changes occur as well as the underlying substrates of the changes including neural, glial, and vasculature components. Aerobic activity has been shown to produce different types of changes in the brain. The presence of novel experiences or learning is an especially imp...

  12. [A case of a penetrating brain injury due to an explosion of a construction machine].

    Science.gov (United States)

    Ibayashi, Kenji; Tsutsumi, Kazuo; Yoshikawa, Gakushi; Uno, Takeshi; Shimada, Shiko; Kawashima, Mariko; Koizumi, Satoshi; Ochiai, Yushi

    2012-05-01

    Penetrating brain injury caused by a high speed projectile is rather rare in Japan, known for its strict gun-control laws. We report a case of a 55-year-old male, who was transferred to our hospital with a foreign body in the brain due to penetrating head injury, which was caused by an explosion of a construction machine. Neurological examination demonstrated severe motor aphagia with no apparent motor paresis. The patient had a scalp laceration on his left forehead with exposed cerebral tissue and CSF leakage. Head CT scan and plain skull X-ray revealed a 20 mm×25 mm bolt which had penetrated due to the explosion of the machine. The anterior wall of the left frontal sinus was fractured resulting in dural laceration, and scattered bone fragments were seen along the trajectory of the bolt. Digital subtraction angiography showed no significant vascular injuries including superior sagittal sinus. We performed open surgery, and successfully removed the bolt along with the damaged frontal lobe. The patient had no infection or seizure after the surgery, and was transferred for further rehabilitation therapy. We performed a cosmetic cranioplasty six months later. Surgical debridement of the damaged cerebral tissue along the trajectory led to successful removal of the bolt with no further neurological deficit. PMID:22538284

  13. Brain ultrasonographic findings of late-onset circulatory dysfunction due to adrenal insufficiency in preterm infants

    Directory of Open Access Journals (Sweden)

    Su-Mi Shin

    2016-07-01

    Full Text Available Purpose: The aim of this study was to characterize the brain ultrasonographic findings of late-onset circulatory dysfunction (LCD due to adrenal insufficiency (AI in preterm infants. Methods: Among the 257 preterm infants born at <33 weeks of gestation between December 2009 and February 2014 at our institution, 35 preterm infants were diagnosed with AI. Brain ultrasonographic findings were retrospectively analyzed before and after LCD in 14 preterm infants, after exclusion of the other 21 infants with AI due to the following causes: death (n=2, early AI (n=5, sepsis (n=1, and patent ductus arteriosus (n=13. Results: Fourteen of 257 infants (5.4% were diagnosed with LCD due to AI. The age at LCD was a median of 18.5 days (range, 9 to 32 days. The last ultrasonographic findings before LCD occurred showed grade 1 periventricular echogenicity (PVE in all 14 patients and germinal matrix hemorrhage (GMH with focal cystic change in one patient. Ultrasonographic findings after LCD demonstrated no significant change in grade 1 PVE and no new lesions in eight (57%, grade 1 PVE with newly appearing GMH in three (21%, and increased PVE in three (21% infants. Five infants (36% showed new development (n=4 or increased size (n=1 of GMH. Two of three infants (14% with increased PVE developed cystic periventricular leukomalacia (PVL and rapid progression to macrocystic encephalomalacia. Conclusion: LCD due to AI may be associated with the late development of GMH, increased PVE after LCD, and cystic PVL with rapid progression to macrocystic encephalomalacia.

  14. Structural changes in amber due to uranium mineralization.

    Science.gov (United States)

    Havelcová, Martina; Machovič, Vladimír; Mizera, Jiří; Sýkorová, Ivana; René, Miloš; Borecká, Lenka; Lapčák, Ladislav; Bičáková, Olga; Janeček, Oldřich; Dvořák, Zdeněk

    2016-07-01

    The presence of uranium, with a bulk mass fraction of about 1.5 wt% and radiolytic alterations are a feature of Cenomanian amber from Křižany, at the northeastern edge of the North Bohemian Cretaceous uranium ore district. Pores and microcracks in the amber were filled with a mineral admixture, mainly in the form of Zr-Y-REE enriched uraninite. As a result of radiolytic alterations due to the presence of uranium, structural changes were observed in the Křižany amber in comparison with a reference amber from Nové Strašecí in central Bohemia; this was of similar age and botanical origin but did not contain elevated levels of uranium. Structural changes involved an increase in aromaticity due to dehydroaromatization of aliphatic cyclic hydrocarbons, loss of oxygen functional groups, an increase in the degree of polymerization, crosslinking of CC bonds, formation of a three-dimensional hydrocarbon network in the bulk organic matrix, and carbonization of the organic matrix around the uraninite infill. PMID:27085038

  15. Structural similarities between brain and linguistic data provide evidence of semantic relations in the brain.

    Directory of Open Access Journals (Sweden)

    Colleen E Crangle

    Full Text Available This paper presents a new method of analysis by which structural similarities between brain data and linguistic data can be assessed at the semantic level. It shows how to measure the strength of these structural similarities and so determine the relatively better fit of the brain data with one semantic model over another. The first model is derived from WordNet, a lexical database of English compiled by language experts. The second is given by the corpus-based statistical technique of latent semantic analysis (LSA, which detects relations between words that are latent or hidden in text. The brain data are drawn from experiments in which statements about the geography of Europe were presented auditorily to participants who were asked to determine their truth or falsity while electroencephalographic (EEG recordings were made. The theoretical framework for the analysis of the brain and semantic data derives from axiomatizations of theories such as the theory of differences in utility preference. Using brain-data samples from individual trials time-locked to the presentation of each word, ordinal relations of similarity differences are computed for the brain data and for the linguistic data. In each case those relations that are invariant with respect to the brain and linguistic data, and are correlated with sufficient statistical strength, amount to structural similarities between the brain and linguistic data. Results show that many more statistically significant structural similarities can be found between the brain data and the WordNet-derived data than the LSA-derived data. The work reported here is placed within the context of other recent studies of semantics and the brain. The main contribution of this paper is the new method it presents for the study of semantics and the brain and the focus it permits on networks of relations detected in brain data and represented by a semantic model.

  16. Imaging structural co-variance between human brain regions

    OpenAIRE

    Alexander-Bloch, Aaron; Giedd, Jay N.; Bullmore, Ed

    2013-01-01

    Brain structure varies between people in a markedly organized fashion. Communities of brain regions co-vary in their morphological properties. For example, cortical thickness in one region influences the thickness of structurally and functionally connected regions. Such networks of structural co-variance partially recapitulate the functional networks of healthy individuals and the foci of grey matter loss in neurodegenerative disease. This architecture is genetically heritable, is associated ...

  17. Brain injury due to acute organophosphate poisoning Magnetic resonance imaging manifestation and pathological characteristics

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Acute organophosphate poisoning can cause injuries of multiple visceras; especially,central nervous system injury can increase risk factors of patients with severe acute organophosphate poisoning. An application of modem image may increase diagnostic rate of brain injury in an earlier period and provide evidences for clinical treatment.OBJECTIVE: To reveal imaging manifestations, pathological characteristics and multi-ways injured mechanism of brain injury due to acute organophosphate poisoning.DESIGN: Contrast observational study.SETTING: Department of Medical Image, the Second Hospital of Hebei Medical University.MATERIALS: The experiment was carried out in the Department of Nerve Molecule Imaging Medicine and Laboratory of Neurology, the Second Hospital of Hebei Medical University from August 2003 to February 2004. A total of 30 healthy cats weighing 2.8 - 3.5 g and of both genders were selected from Animal Experimental Center of Hebei Medical University.METHODS: Thirty healthy cats were randomly divided into control group (n =5) and intoxication group (n=25). Cats in the control group were subcutaneously injected with 0.3 mL/kg saline at four points; while, cats in the intoxication group were subcutaneously injected with 400 g/L 0.3 mL/kg O,O-dimethyl-S-(methoxycarbonylmethyl) thiophosphate at four points. Two minutes after intoxication, cats received muscular injection with 0.5 mg/kg atropine sulfate, and then, brain tissues were collected from parietal lobe, basal ganglia, hippocampus, cerebellum and brain stem were observed at 3, 6, 24 hours, 3 and 7 days after intoxication respectively under optic microscope and electron microscope and expressions of acetylcholinesterase (AChE), choline acetyltransferase (ChAT), glial fibrillary acidic protein (GFAP),glutamic acid (Glu) and γ-amino butyric acid after immunohistochemical staining.MAIN OUTCOME MEASURES: Results of MRI examinations; histological changes under optic microscope and electron

  18. Methamphetamine Alters Brain Structures, Impairs Mental Flexibility

    Science.gov (United States)

    ... Latinos Inmates and Parolees International Populations LGBT Populations Low Income Populations Men Military and Veterans Native Hawaiians and ... Health Grant Awards Mark the Launch of Landmark Adolescent Brain Cognitive Development (ABCD) Study Addiction Science Can ...

  19. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivieres, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Loohuis, Loes M. Olde; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santianez, Roberto; Rose, Emma J.; Salami, Alireza; Saemann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Puetz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Goering, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzah, Eva; Melle, Ingrid; Mahnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Muehleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Noethen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdes Hernandez, Maria C.; van't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffman, Wolfgang; Hosten, Norbert; Kahn, Rene S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Mueller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Voelzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernandez, Guillen; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Pol, Hilleke E. Hulshoff; Joensson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M.; Ophoff, Roel A.; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S.; Saykin, Andrew J.; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M.; Weale, Michael E.; Weinberger, Daniel R.; Adams, Hieab H. H.; Launer, Lenore J.; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L.; Becker, James T.; Yanek, Lisa; van der Lee, Sven J.; Ebling, Maritza; Fischl, Bruce; Longstreth, W. T.; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N.; van Duijn, Cornelia M.; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C.; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M. Arfan; Martin, Nicholas G.; Wright, Margaret J.; Schumann, Gunter; Franke, Barbara; Thompson, Paul M.; Medland, Sarah E.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences(1). Subcortical brain regions form circuits with cortical areas to coordinate movement(2), learning, memory(3) and motivation(4), and altered circuits can lead to abnormal behaviour and disease(5). To investigat

  20. Common genetic variants influence human subcortical brain structures

    NARCIS (Netherlands)

    D.P. Hibar (Derrek); J.L. Stein; M.E. Rentería (Miguel); A. Arias-Vásquez (Alejandro); S. Desrivières (Sylvane); N. Jahanshad (Neda); R. Toro (Roberto); K. Wittfeld (Katharina); L. Abramovic; M. Andersson (Micael); B. Aribisala (Benjamin); N.J. Armstrong (Nicola J.); M. Bernard (Manon); M.M. Bohlken (Marc M.); M.P.M. Boks (Marco); L.B.C. Bralten (Linda); A.A. Brown (Andrew); M.M. Chakravarty (M. Mallar); Q. Chen (Qiang); C.R.K. Ching (Christopher); G. Cuellar-Partida (Gabriel); A. den Braber (Anouk); S. Giddaluru (Sudheer); A.L. Goldman (Aaron L.); O. Grimm (Oliver); T. Guadalupe (Tulio); J. Hass (Johanna); G. Woldehawariat (Girma); A.J. Holmes (Avram); M. Hoogman (Martine); D. Janowitz (Deborah); T. Jia (Tianye); S. Kim (Shinseog); M. Klein (Marieke); B. Kraemer (Bernd); P.H. Lee (Phil H.); L.M. Olde Loohuis (Loes M.); M. Luciano (Michelle); C. MacAre (Christine); R. Mather; M. Mattheisen (Manuel); Y. Milaneschi (Yuri); K. Nho (Kwangsik); M. Papmeyer (Martina); A. Ramasamy (Adaikalavan); S.L. Risacher (Shannon); R. Roiz-Santiañez (Roberto); E.J. Rose (Emma); A. Salami (Alireza); P.G. Sämann (Philipp); L. Schmaal (Lianne); N.J. Schork (Nicholas); J. Shin (Jean); V.M. Strike (Vanessa); A. Teumer (Alexander); M.M.J. Van Donkelaar (Marjolein M. J.); K.R. van Eijk (Kristel); R.K. Walters (Raymond); L.T. Westlye (Lars); C.D. Whelan (Christopher); A.M. Winkler (Anderson); M.P. Zwiers (Marcel); S. Alhusaini (Saud); L. Athanasiu (Lavinia); S.M. Ehrlich (Stefan); M. Hakobjan (Marina); C.B. Hartberg (Cecilie B.); U.K. Haukvik (Unn); A.J.G.A.M. Heister (Angelien J. G. A. M.); D. Hoehn (David); D. Kasperaviciute (Dalia); D.C. Liewald (David C.); L.M. Lopez (Lorna); R.R.R. Makkinje (Remco R. R.); M. Matarin (Mar); M.A.M. Naber (Marlies A. M.); D. Reese McKay; M. Needham (Margaret); A.C. Nugent (Allison); B. Pütz (Benno); N.A. Royle (Natalie); L. Shen (Li); R. Sprooten (Roy); D. Trabzuni (Danyah); S.S.L. Van Der Marel (Saskia S. L.); K.J.E. Van Hulzen (Kimm J. E.); E. Walton (Esther); A. Björnsson (Asgeir); L. Almasy (Laura); D. Ames (David); S. Arepalli (Sampath); A.A. Assareh; M.E. Bastin (Mark); H. Brodaty (Henry); K. Bulayeva (Kazima); M.A. Carless (Melanie); S. Cichon (Sven); A. Corvin (Aiden); J.E. Curran (Joanne); M. Czisch (Michael); G.I. de Zubicaray (Greig); A. Dillman (Allissa); A. Duggirala (Aparna); M.D. Dyer (Matthew); S. Erk; I. Fedko (Iryna); L. Ferrucci (Luigi); T. Foroud (Tatiana); P.T. Fox (Peter); M. Fukunaga (Masaki); J. Raphael Gibbs; H.H.H. Göring (Harald H.); R.C. Green (Robert C.); S. Guelfi (Sebastian); N.K. Hansell (Narelle); C.A. Hartman (Catharina); K. Hegenscheid (Katrin); J. Heinz (Judith); D.G. Hernandez (Dena); D.J. Heslenfeld (Dirk); P.J. Hoekstra (Pieter); F. Holsboer; G. Homuth (Georg); J.J. Hottenga (Jouke Jan); M. Ikeda (Masashi); C.R. Jack Jr. (Clifford); S. Jenkinson (Sarah); R. Johnson (Robert); R. Kanai (Ryota); M. Keil (Maria); J.W. Kent (Jack W.); P. Kochunov (Peter); J.B. Kwok (John B.); S. Lawrie (Stephen); X. Liu (Xinmin); D.L. Longo (Dan L.); K.L. Mcmahon (Katie); E. Meisenzahl (Eva); I. Melle (Ingrid); S. Mohnke (Sebastian); G.W. Montgomery (Grant); J.C. Mostert (Jeanette C.); T.W. Mühleisen (Thomas); M.A. Nalls (Michael); T.E. Nichols (Thomas); L.G. Nilsson; M.M. Nöthen (Markus); K. Ohi (Kazutaka); R.L. Olvera (Rene); R. Perez-Iglesias (Rocio); G. Bruce Pike; S.G. Potkin (Steven); I. Reinvang (Ivar); S. Reppermund; M. Rietschel (M.); N. Seiferth (Nina); G.D. Rosen (Glenn D.); D. Rujescu (Dan); K. Schnell (Kerry); C.J. Schofield (Christopher); C. Smith (Colin); V.M. Steen (Vidar); J. Sussmann (Jessika); A. Thalamuthu (Anbupalam); A.W. Toga (Arthur W.); B. Traynor (Bryan); J.C. Troncoso (Juan); J. Turner (Jessica); M.C. Valdés Hernández (Maria); D. van 't Ent (Dennis); M.P. van der Brug (Marcel); N.J. van der Wee (Nic); M.J.D. van Tol (Marie-José); D.J. Veltman (Dick); A.M.J. Wassink (Annemarie); E. Westman (Eric); R.H. Zielke (Ronald H.); A.B. Zonderman (Alan B.); D.G. Ashbrook (David G.); R. Hager (Reinmar); L. Lu (Lu); F.J. Mcmahon (Francis J); D.W. Morris (Derek W); R.W. Williams (Robert W.); H.G. Brunner; M. Buckner; J.K. Buitelaar (Jan K.); W. Cahn (Wiepke); V.D. Calhoun Vince D. (V.); G. Cavalleri (Gianpiero); B. Crespo-Facorro (Benedicto); A.M. Dale (Anders); G.E. Davies (Gareth); N. Delanty; C. Depondt (Chantal); S. Djurovic (Srdjan); D.A. Drevets (Douglas); T. Espeseth (Thomas); R.L. Gollub (Randy); B.C. Ho (Beng ); W. Hoffmann (Wolfgang); N. Hosten (Norbert); R. Kahn; S. Le Hellard (Stephanie); A. Meyer-Lindenberg; B. Müller-Myhsok (B.); M. Nauck (Matthias); L. Nyberg (Lars); M. Pandolfo (Massimo); B.W.J.H. Penninx (Brenda); J.L. Roffman (Joshua); S.M. Sisodiya (Sanjay); J.W. Smoller; H. van Bokhoven (Hans); N.E.M. van Haren (Neeltje E.); H. Völzke (Henry); H.J. Walter (Henrik); M.W. Weiner (Michael); W. Wen (Wei); T.J.H. White (Tonya); I. Agartz (Ingrid); O.A. Andreassen (Ole A.); J. Blangero (John); D.I. Boomsma (Dorret); R.M. Brouwer (Rachel); D.M. Cannon (Dara); M.R. Cookson (Mark); E.J.C. de Geus (Eco); I.J. Deary (Ian J.); D.J. Donohoe (Dennis); G. Fernandez (Guillén); S.E. Fisher (Simon); C. Francks (Clyde); D.C. Glahn (David); H.J. Grabe (Hans Jörgen); O. Gruber (Oliver); J. Hardy (John); R. Hashimoto (Ryota); H.E. Hulshoff Pol (Hilleke); E.G. Jönsson (Erik); I. Kloszewska (Iwona); S. Lovestone (Simon); V.S. Mattay (Venkata S.); P. Mecocci (Patrizia); C. McDonald (Colm); A.M. McIntosh (Andrew); R.A. Ophoff (Roel); T. Paus (Tomas); Z. Pausova (Zdenka); M. Ryten (Mina); P.S. Sachdev (Perminder); A.J. Saykin (Andrew); A. Simmons (Andrew); A. Singleton (Andrew); H. Soininen (H.); J.M. Wardlaw (J.); M.E. Weale (Michael); D.R. Weinberger (Daniel); H.H.H. Adams (Hieab); L.J. Launer (Lenore); S. Seiler (Stephan); R. Schmidt (Reinhold); G. Chauhan (Ganesh); C.L. Satizabal (Claudia L.); J.T. Becker (James); L.R. Yanek (Lisa); S. van der Lee (Sven); M. Ebling (Maritza); B. Fischl (Bruce); W.T. Longstreth Jr; D. Greve (Douglas); R. Schmidt (Reinhold); P. Nyquist (Paul); L.N. Vinke (Louis N.); C.M. van Duijn (Cock); L. Xue (Luting); B. Mazoyer (Bernard); J.C. Bis (Joshua); V. Gudnason (Vilmundur); S. Seshadri (Sudha); M.A. Ikram (Arfan); N.G. Martin (Nicholas); M.J. Wright (Margaret); G. Schumann (Gunter); B. Franke (Barbara); P.M. Thompson (Paul); S.E. Medland (Sarah Elizabeth)

    2015-01-01

    textabstractThe highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate h

  1. Connectivity and functional profiling of abnormal brain structures in pedophilia

    Science.gov (United States)

    Poeppl, Timm B.; Eickhoff, Simon B.; Fox, Peter T.; Laird, Angela R.; Rupprecht, Rainer; Langguth, Berthold; Bzdok, Danilo

    2015-01-01

    Despite its 0.5–1% lifetime prevalence in men and its general societal relevance, neuroimaging investigations in pedophilia are scarce. Preliminary findings indicate abnormal brain structure and function. However, no study has yet linked structural alterations in pedophiles to both connectional and functional properties of the aberrant hotspots. The relationship between morphological alterations and brain function in pedophilia as well as their contribution to its psychopathology thus remain unclear. First, we assessed bimodal connectivity of structurally altered candidate regions using meta-analytic connectivity modeling (MACM) and resting-state correlations employing openly accessible data. We compared the ensuing connectivity maps to the activation likelihood estimation (ALE) maps of a recent quantitative meta-analysis of brain activity during processing of sexual stimuli. Second, we functionally characterized the structurally altered regions employing meta-data of a large-scale neuroimaging database. Candidate regions were functionally connected to key areas for processing of sexual stimuli. Moreover, we found that the functional role of structurally altered brain regions in pedophilia relates to nonsexual emotional as well as neurocognitive and executive functions, previously reported to be impaired in pedophiles. Our results suggest that structural brain alterations affect neural networks for sexual processing by way of disrupted functional connectivity, which may entail abnormal sexual arousal patterns. The findings moreover indicate that structural alterations account for common affective and neurocognitive impairments in pedophilia. The present multi-modal integration of brain structure and function analyses links sexual and nonsexual psychopathology in pedophilia. PMID:25733379

  2. Mapping human whole-brain structural networks with diffusion MRI.

    Directory of Open Access Journals (Sweden)

    Patric Hagmann

    Full Text Available Understanding the large-scale structural network formed by neurons is a major challenge in system neuroscience. A detailed connectivity map covering the entire brain would therefore be of great value. Based on diffusion MRI, we propose an efficient methodology to generate large, comprehensive and individual white matter connectional datasets of the living or dead, human or animal brain. This non-invasive tool enables us to study the basic and potentially complex network properties of the entire brain. For two human subjects we find that their individual brain networks have an exponential node degree distribution and that their global organization is in the form of a small world.

  3. Changes in secondary structure of gluten proteins due to emulsifiers

    Science.gov (United States)

    Gómez, Analía V.; Ferrer, Evelina G.; Añón, María C.; Puppo, María C.

    2013-02-01

    Changes in the secondary structure of gluten proteins due to emulsifiers were analyzed by Raman Spectroscopy. The protein folding induced by 0.25% SSL (Sodium Stearoyl Lactylate) (GS0.25, Gluten + 0.25% SSL) included an increase in α-helix conformation and a decrease in β-sheet, turns and random coil. The same behavior, although in a less degree, was observed for 0.5% gluten-DATEM (Diacetyl Tartaric Acid Esters of Monoglycerides) system. The low burial of Tryptophan residues to a more hydrophobic environment and the low percentage area of the C-H stretching band for GS0.25 (Gluten + 0.25% SSL), could be related to the increased in α-helix conformation. This behavior was also confirmed by changes in stretching vibrational modes of disulfide bridges (S-S) and the low exposure of Tyrosine residues. High levels of SSL (0.5% and 1.0%) and DATEM (1.0%) led to more disordered protein structures, with different gluten networks. SSL (1.0%) formed a more disordered and opened gluten matrix than DATEM, the last one being laminar and homogeneous.

  4. Label-free structural photoacoustic tomography of intact mouse brain

    Science.gov (United States)

    Li, Lei; Xia, Jun; Li, Guo; Garcia-Uribe, Alejandro; Wang, Lihong V.

    2015-03-01

    Capitalizing on endogenous hemoglobin contrast, photoacoustic computed tomography (PACT), a deep-tissue highresolution imaging modality, has drawn increasing interest in neuro-imaging. However, most existing studies are limited to functional imaging on the cortical surface, and the deep-brain structural imaging capability of PACT has never been demonstrated. Here, we explicitly studied the limiting factors of deep-brain PACT imaging. We found that the skull distorted the acoustic signal and blood suppressed the structural contrast from other chromophores. When the two effects are mitigated, PACT can provide high-resolution label-free structural imaging through the entire mouse brain. With 100 μm in-plane resolution, we can clearly identify major structures of the brain, and the image quality is comparable to that of magnetic resonance microscopy. Spectral PACT studies indicate that structural contrasts mainly originate from cytochrome and lipid. The feasibility of imaging the structure of the brain in vivo has also been discussed. Our results demonstrate that PACT is a promising modality for both structural and functional brain imaging.

  5. Structural MRI studies of language function in the undamaged brain

    OpenAIRE

    Richardson, F. M.; Price, C.J.

    2009-01-01

    In recent years, the demonstration that structural changes can occur in the human brain beyond those associated with development, ageing and neuropathology has revealed a new approach to studying the neural basis of behaviour. In this review paper, we focus on structural imaging studies of language that have utilised behavioural measures in order to investigate the neural correlates of language skills in the undamaged brain. We report studies that have used two different techniques: voxel-bas...

  6. Post-mortem Findings in Huntington’s Deep Brain Stimulation: A Moving Target Due to Atrophy

    Science.gov (United States)

    Vedam-Mai, Vinata; Martinez-Ramirez, Daniel; Hilliard, Justin D.; Carbunaru, Samuel; Yachnis, Anthony T.; Bloom, Joshua; Keeling, Peyton; Awe, Lisa; Foote, Kelly D.; Okun, Michael S.

    2016-01-01

    Background Deep brain stimulation (DBS) has been shown to be effective for Parkinson’s disease, essential tremor, and primary dystonia. However, mixed results have been reported in Huntington’s disease (HD). Case Report A single case of HD DBS was identified from the University of Florida DBS Brain Tissue Network. The clinical presentation, evolution, surgical planning, DBS parameters, clinical outcomes, and brain pathological changes are summarized. Discussion This case of HD DBS revealed that chorea may improve and be sustained. Minimal histopathological changes were noted around the DBS leads. Severe atrophy due to HD likely changed the DBS lead position relative to the internal capsule. PMID:27127722

  7. Olanzapine and Betamethasone Are Effective for the Treatment of Nausea and Vomiting due to Metastatic Brain Tumors of Rectal Cancer

    Directory of Open Access Journals (Sweden)

    M. Suzuki

    2014-01-01

    Full Text Available Brain lesions originating from metastasis of colorectal cancer represent 3-5% of all brain metastases and are relatively rare. Of all distant metastases of colorectal cancer, those to the liver are detected in 22-29% of cases, while those to the lungs are detected in 8-18% of cases. In contrast, brain metastasis is quite rare, with a reported incidence ranging from 0.4 to 1.8%. Treatments for metastatic brain tumors include surgery, radiotherapy, chemotherapy and supportive care with steroids, etc. Untreated patients exhibit a median survival of only approximately 1 month. The choice of treatment for brain metastasis depends on the number of lesions, the patient's general condition, nerve findings and presence of other metastatic lesions. We herein report the case of a 78-year-old male who presented with brain metastases originating from rectal carcinoma. He suffered from nausea, vomiting, anorexia and vertigo during body movement. He received antiemetics, glycerol and whole brain radiation therapy; however, these treatments proved ineffective. Olanzapine therapy was started at a dose of 1.25 mg every night. The persistent nausea disappeared the next day, and the frequency of vomiting subsequently decreased. The patient was able to consume solid food. Olanzapine is an antipsychotic that has recently been used as palliative therapy for refractory nausea and vomiting in patients receiving chemotherapy. We consider that olanzapine was helpful as a means of supportive care for the treatment of nausea and vomiting due to brain metastasis.

  8. The effects of physical activity on brain structure

    Directory of Open Access Journals (Sweden)

    Adam eThomas

    2012-03-01

    Full Text Available Aerobic activity is a powerful stimulus for improving mental health and for generating structural changes in the brain. We review the literature documenting these structural changes and explore exactly where in the brain these changes occur as well as the underlying substrates of the changes including neural, glial, and vasculature components. Aerobic activity has been shown to produce different types of changes in the brain. The presence of novel experiences or learning is an especially important component in how these changes are manifest. We also discuss the distinct time courses of structural brain changes with both aerobic activity and learning as well as how these effects might differ in diseased and elderly groups.

  9. A Thoracic Mechanism of Mild Traumatic Brain Injury Due to Blast Pressure Waves

    OpenAIRE

    Courtney, Amy; Courtney, Michael

    2008-01-01

    The mechanisms by which blast pressure waves cause mild to moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast pressure wave reaches the brain via a thoracic mechanism is considered in light of ballistic and blast pressure wave research. Ballistic pressure waves, caused by penetrating b...

  10. Self-portraits of the brain: cognitive science, data visualization, and communicating brain structure and function.

    Science.gov (United States)

    Goldstone, Robert L; Pestilli, Franco; Börner, Katy

    2015-08-01

    With several large-scale human brain projects currently underway and a range of neuroimaging techniques growing in availability to researchers, the amount and diversity of data relevant for understanding the human brain is increasing rapidly. A complete understanding of the brain must incorporate information about 3D neural location, activity, timing, and task. Data mining, high-performance computing, and visualization can serve as tools that augment human intellect; however, the resulting visualizations must take into account human abilities and limitations to be effective tools for exploration and communication. In this feature review, we discuss key challenges and opportunities that arise when leveraging the sophisticated perceptual and conceptual processing of the human brain to help researchers understand brain structure, function, and behavior.

  11. Brain structure predicts risk for obesity ☆

    OpenAIRE

    Smucny, Jason; Cornier, Marc-Andre; Eichman, Lindsay C.; Thomas, Elizabeth A.; Bechtell, Jamie L.; Tregellas, Jason R.

    2012-01-01

    The neurobiology of obesity is poorly understood. Here we report findings of a study designed to examine the differences in brain regional gray matter volume in adults recruited as either Obese Prone or Obese Resistant based on self-identification, body mass index, and personal/family weight history. Magnetic resonance imaging was performed in 28 Obese Prone (14 male, 14 female) and 25 Obese Resistant (13 male, 12 female) healthy adults. Voxel-based morphometry was used to identify gray matte...

  12. Joint Modelling of Structural and Functional Brain Networks

    DEFF Research Database (Denmark)

    Andersen, Kasper Winther; Herlau, Tue; Mørup, Morten;

    Functional and structural magnetic resonance imaging have become the most important noninvasive windows to the human brain. A major challenge in the analysis of brain networks is to establish the similarities and dissimilarities between functional and structural connectivity. We formulate a non......-parametric Bayesian network model which allows for joint modelling and integration of multiple networks. We demonstrate the model’s ability to detect vertices that share structure across networks jointly in functional MRI (fMRI) and diffusion MRI (dMRI) data. Using two fMRI and dMRI scans per subject, we establish...... significant structures that are consistently shared across subjects and data splits. This provides an unsupervised approach for modeling of structure-function relations in the brain and provides a general framework for multimodal integration....

  13. Do brain image databanks support understanding of normal ageing brain structure? A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Dickie, David Alexander; Job, Dominic E.; Wardlaw, Joanna M. [University of Edinburgh, Division of Clinical Neurosciences, Western General Hospital, Brain Research Imaging Centre (BRIC), Edinburgh (United Kingdom); Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE), Edinburgh (United Kingdom); Poole, Ian [Toshiba Medical Visualisation Systems Europe, Ltd., Edinburgh (United Kingdom); Ahearn, Trevor S.; Staff, Roger T.; Murray, Alison D. [University of Aberdeen, Aberdeen Biomedical Imaging Centre, Aberdeen (United Kingdom); Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE), Edinburgh (United Kingdom)

    2012-07-15

    To document accessible magnetic resonance (MR) brain images, metadata and statistical results from normal older subjects that may be used to improve diagnoses of dementia. We systematically reviewed published brain image databanks (print literature and Internet) concerned with normal ageing brain structure. From nine eligible databanks, there appeared to be 944 normal subjects aged {>=}60 years. However, many subjects were in more than one databank and not all were fully representative of normal ageing clinical characteristics. Therefore, there were approximately 343 subjects aged {>=}60 years with metadata representative of normal ageing, but only 98 subjects were openly accessible. No databank had the range of MR image sequences, e.g. T2*, fluid-attenuated inversion recovery (FLAIR), required to effectively characterise the features of brain ageing. No databank supported random subject retrieval; therefore, manual selection bias and errors may occur in studies that use these subjects as controls. Finally, no databank stored results from statistical analyses of its brain image and metadata that may be validated with analyses of further data. Brain image databanks require open access, more subjects, metadata, MR image sequences, searchability and statistical results to improve understanding of normal ageing brain structure and diagnoses of dementia. (orig.)

  14. Common genetic variants influence human subcortical brain structures.

    Science.gov (United States)

    Hibar, Derrek P; Stein, Jason L; Renteria, Miguel E; Arias-Vasquez, Alejandro; Desrivières, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S; Armstrong, Nicola J; Bernard, Manon; Bohlken, Marc M; Boks, Marco P; Bralten, Janita; Brown, Andrew A; Chakravarty, M Mallar; Chen, Qiang; Ching, Christopher R K; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H; Olde Loohuis, Loes M; Luciano, Michelle; Macare, Christine; Mather, Karen A; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L; Roiz-Santiañez, Roberto; Rose, Emma J; Salami, Alireza; Sämann, Philipp G; Schmaal, Lianne; Schork, Andrew J; Shin, Jean; Strike, Lachlan T; Teumer, Alexander; van Donkelaar, Marjolein M J; van Eijk, Kristel R; Walters, Raymond K; Westlye, Lars T; Whelan, Christopher D; Winkler, Anderson M; Zwiers, Marcel P; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M H; Hartberg, Cecilie B; Haukvik, Unn K; Heister, Angelien J G A M; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C M; Lopez, Lorna M; Makkinje, Remco R R; Matarin, Mar; Naber, Marlies A M; McKay, D Reese; Needham, Margaret; Nugent, Allison C; Pütz, Benno; Royle, Natalie A; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S L; van Hulzen, Kimm J E; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A; Bastin, Mark E; Brodaty, Henry; Bulayeva, Kazima B; Carless, Melanie A; Cichon, Sven; Corvin, Aiden; Curran, Joanne E; Czisch, Michael; de Zubicaray, Greig I; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D; Erk, Susanne; Fedko, Iryna O; Ferrucci, Luigi; Foroud, Tatiana M; Fox, Peter T; Fukunaga, Masaki; Gibbs, J Raphael; Göring, Harald H H; Green, Robert C; Guelfi, Sebastian; Hansell, Narelle K; Hartman, Catharina A; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G; Heslenfeld, Dirk J; Hoekstra, Pieter J; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W; Kochunov, Peter; Kwok, John B; Lawrie, Stephen M; Liu, Xinmin; Longo, Dan L; McMahon, Katie L; Meisenzahl, Eva; Melle, Ingrid; Mohnke, Sebastian; Montgomery, Grant W; Mostert, Jeanette C; Mühleisen, Thomas W; Nalls, Michael A; Nichols, Thomas E; Nilsson, Lars G; Nöthen, Markus M; Ohi, Kazutaka; Olvera, Rene L; Perez-Iglesias, Rocio; Pike, G Bruce; Potkin, Steven G; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D; Rujescu, Dan; Schnell, Knut; Schofield, Peter R; Smith, Colin; Steen, Vidar M; Sussmann, Jessika E; Thalamuthu, Anbupalam; Toga, Arthur W; Traynor, Bryan J; Troncoso, Juan; Turner, Jessica A; Valdés Hernández, Maria C; van 't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J A; van Tol, Marie-Jose; Veltman, Dick J; Wassink, Thomas H; Westman, Eric; Zielke, Ronald H; Zonderman, Alan B; Ashbrook, David G; Hager, Reinmar; Lu, Lu; McMahon, Francis J; Morris, Derek W; Williams, Robert W; Brunner, Han G; Buckner, Randy L; Buitelaar, Jan K; Cahn, Wiepke; Calhoun, Vince D; Cavalleri, Gianpiero L; Crespo-Facorro, Benedicto; Dale, Anders M; Davies, Gareth E; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C; Espeseth, Thomas; Gollub, Randy L; Ho, Beng-Choon; Hoffmann, Wolfgang; Hosten, Norbert; Kahn, René S; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Müller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W J H; Roffman, Joshua L; Sisodiya, Sanjay M; Smoller, Jordan W; van Bokhoven, Hans; van Haren, Neeltje E M; Völzke, Henry; Walter, Henrik; Weiner, Michael W; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A; Blangero, John; Boomsma, Dorret I; Brouwer, Rachel M; Cannon, Dara M; Cookson, Mark R; de Geus, Eco J C; Deary, Ian J; Donohoe, Gary; Fernández, Guillén; Fisher, Simon E; Francks, Clyde; Glahn, David C; Grabe, Hans J; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Hulshoff Pol, Hilleke E; Jönsson, Erik G; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M; Ophoff, Roel A; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S; Saykin, Andrew J; Simmons, Andy; Singleton, Andrew; Soininen, Hilkka; Wardlaw, Joanna M; Weale, Michael E; Weinberger, Daniel R; Adams, Hieab H H; Launer, Lenore J; Seiler, Stephan; Schmidt, Reinhold; Chauhan, Ganesh; Satizabal, Claudia L; Becker, James T; Yanek, Lisa; van der Lee, Sven J; Ebling, Maritza; Fischl, Bruce; Longstreth, W T; Greve, Douglas; Schmidt, Helena; Nyquist, Paul; Vinke, Louis N; van Duijn, Cornelia M; Xue, Luting; Mazoyer, Bernard; Bis, Joshua C; Gudnason, Vilmundur; Seshadri, Sudha; Ikram, M Arfan; Martin, Nicholas G; Wright, Margaret J; Schumann, Gunter; Franke, Barbara; Thompson, Paul M; Medland, Sarah E

    2015-04-01

    The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume and intracranial volume. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10(-33); 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability in human brain development, and may help to determine mechanisms of neuropsychiatric dysfunction. PMID:25607358

  15. Common genetic variants influence human subcortical brain structures

    Science.gov (United States)

    Hibar, Derrek P.; Stein, Jason L.; Renteria, Miguel E.; Arias-Vasquez, Alejandro; Desrivières, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S.; Armstrong, Nicola J.; Bernard, Manon; Bohlken, Marc M.; Boks, Marco P.; Bralten, Janita; Brown, Andrew A.; Chakravarty, M. Mallar; Chen, Qiang; Ching, Christopher R. K.; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L.; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J.; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H.; Olde Loohuis, Loes M.; Luciano, Michelle; Macare, Christine; Mather, Karen A.; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L.; Roiz-Santiañez, Roberto; Rose, Emma J.; Salami, Alireza; Sämann, Philipp G.; Schmaal, Lianne; Schork, Andrew J.; Shin, Jean; Strike, Lachlan T.; Teumer, Alexander; van Donkelaar, Marjolein M. J.; van Eijk, Kristel R.; Walters, Raymond K.; Westlye, Lars T.; Whelan, Christopher D.; Winkler, Anderson M.; Zwiers, Marcel P.; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M. H.; Hartberg, Cecilie B.; Haukvik, Unn K.; Heister, Angelien J. G. A. M.; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C. M.; Lopez, Lorna M.; Makkinje, Remco R. R.; Matarin, Mar; Naber, Marlies A. M.; McKay, D. Reese; Needham, Margaret; Nugent, Allison C.; Pütz, Benno; Royle, Natalie A.; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S. L.; van Hulzen, Kimm J. E.; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A.; Bastin, Mark E.; Brodaty, Henry; Bulayeva, Kazima B.; Carless, Melanie A.; Cichon, Sven; Corvin, Aiden; Curran, Joanne E.; Czisch, Michael; de Zubicaray, Greig I.; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D.; Erk, Susanne; Fedko, Iryna O.; Ferrucci, Luigi; Foroud, Tatiana M.; Fox, Peter T.; Fukunaga, Masaki; Gibbs, J. Raphael; Göring, Harald H. H.; Green, Robert C.; Guelfi, Sebastian; Hansell, Narelle K.; Hartman, Catharina A.; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G.; Heslenfeld, Dirk J.; Hoekstra, Pieter J.; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R.; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W.; Kochunov, Peter; Kwok, John B.; Lawrie, Stephen M.; Liu, Xinmin; Longo, Dan L.; McMahon, Katie L.; Meisenzahl, Eva; Melle, Ingrid; Mohnke, Sebastian; Montgomery, Grant W.; Mostert, Jeanette C.; Mühleisen, Thomas W.; Nalls, Michael A.; Nichols, Thomas E.; Nilsson, Lars G.; Nöthen, Markus M.; Ohi, Kazutaka; Olvera, Rene L.; Perez-Iglesias, Rocio; Pike, G. Bruce; Potkin, Steven G.; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D.; Rujescu, Dan; Schnell, Knut; Schofield, Peter R.; Smith, Colin; Steen, Vidar M.; Sussmann, Jessika E.; Thalamuthu, Anbupalam; Toga, Arthur W.; Traynor, Bryan J.; Troncoso, Juan; Turner, Jessica A.; Valdés Hernández, Maria C.; van ’t Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J. A.; van Tol, Marie-Jose; Veltman, Dick J.; Wassink, Thomas H.; Westman, Eric; Zielke, Ronald H.; Zonderman, Alan B.; Ashbrook, David G.; Hager, Reinmar; Lu, Lu; McMahon, Francis J.; Morris, Derek W.; Williams, Robert W.; Brunner, Han G.; Buckner, Randy L.; Buitelaar, Jan K.; Cahn, Wiepke; Calhoun, Vince D.; Cavalleri, Gianpiero L.; Crespo-Facorro, Benedicto; Dale, Anders M.; Davies, Gareth E.; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C.; Espeseth, Thomas; Gollub, Randy L.; Ho, Beng-Choon; Hoffmann, Wolfgang; Hosten, Norbert; Kahn, René S.; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Müller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W. J. H.; Roffman, Joshua L.; Sisodiya, Sanjay M.; Smoller, Jordan W.; van Bokhoven, Hans; van Haren, Neeltje E. M.; Völzke, Henry; Walter, Henrik; Weiner, Michael W.; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A.; Blangero, John; Boomsma, Dorret I.; Brouwer, Rachel M.; Cannon, Dara M.; Cookson, Mark R.; de Geus, Eco J. C.; Deary, Ian J.; Donohoe, Gary; Fernández, Guillén; Fisher, Simon E.; Francks, Clyde; Glahn, David C.; Grabe, Hans J.; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Hulshoff Pol, Hilleke E.; Jönsson, Erik G.; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S.

    2015-01-01

    The highly complex structure of the human brain is strongly shaped by genetic influences1. Subcortical brain regions form circuits with cortical areas to coordinate movement2, learning, memory3 and motivation4, and altered circuits can lead to abnormal behaviour and disease2. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume5 and intracranial volume6. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10−33; 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability inhuman brain development, and may help to determine mechanisms of neuropsychiatric dysfunction. PMID:25607358

  16. Common genetic variants influence human subcortical brain structures.

    Science.gov (United States)

    Hibar, Derrek P; Stein, Jason L; Renteria, Miguel E; Arias-Vasquez, Alejandro; Desrivières, Sylvane; Jahanshad, Neda; Toro, Roberto; Wittfeld, Katharina; Abramovic, Lucija; Andersson, Micael; Aribisala, Benjamin S; Armstrong, Nicola J; Bernard, Manon; Bohlken, Marc M; Boks, Marco P; Bralten, Janita; Brown, Andrew A; Chakravarty, M Mallar; Chen, Qiang; Ching, Christopher R K; Cuellar-Partida, Gabriel; den Braber, Anouk; Giddaluru, Sudheer; Goldman, Aaron L; Grimm, Oliver; Guadalupe, Tulio; Hass, Johanna; Woldehawariat, Girma; Holmes, Avram J; Hoogman, Martine; Janowitz, Deborah; Jia, Tianye; Kim, Sungeun; Klein, Marieke; Kraemer, Bernd; Lee, Phil H; Olde Loohuis, Loes M; Luciano, Michelle; Macare, Christine; Mather, Karen A; Mattheisen, Manuel; Milaneschi, Yuri; Nho, Kwangsik; Papmeyer, Martina; Ramasamy, Adaikalavan; Risacher, Shannon L; Roiz-Santiañez, Roberto; Rose, Emma J; Salami, Alireza; Sämann, Philipp G; Schmaal, Lianne; Schork, Andrew J; Shin, Jean; Strike, Lachlan T; Teumer, Alexander; van Donkelaar, Marjolein M J; van Eijk, Kristel R; Walters, Raymond K; Westlye, Lars T; Whelan, Christopher D; Winkler, Anderson M; Zwiers, Marcel P; Alhusaini, Saud; Athanasiu, Lavinia; Ehrlich, Stefan; Hakobjan, Marina M H; Hartberg, Cecilie B; Haukvik, Unn K; Heister, Angelien J G A M; Hoehn, David; Kasperaviciute, Dalia; Liewald, David C M; Lopez, Lorna M; Makkinje, Remco R R; Matarin, Mar; Naber, Marlies A M; McKay, D Reese; Needham, Margaret; Nugent, Allison C; Pütz, Benno; Royle, Natalie A; Shen, Li; Sprooten, Emma; Trabzuni, Daniah; van der Marel, Saskia S L; van Hulzen, Kimm J E; Walton, Esther; Wolf, Christiane; Almasy, Laura; Ames, David; Arepalli, Sampath; Assareh, Amelia A; Bastin, Mark E; Brodaty, Henry; Bulayeva, Kazima B; Carless, Melanie A; Cichon, Sven; Corvin, Aiden; Curran, Joanne E; Czisch, Michael; de Zubicaray, Greig I; Dillman, Allissa; Duggirala, Ravi; Dyer, Thomas D; Erk, Susanne; Fedko, Iryna O; Ferrucci, Luigi; Foroud, Tatiana M; Fox, Peter T; Fukunaga, Masaki; Gibbs, J Raphael; Göring, Harald H H; Green, Robert C; Guelfi, Sebastian; Hansell, Narelle K; Hartman, Catharina A; Hegenscheid, Katrin; Heinz, Andreas; Hernandez, Dena G; Heslenfeld, Dirk J; Hoekstra, Pieter J; Holsboer, Florian; Homuth, Georg; Hottenga, Jouke-Jan; Ikeda, Masashi; Jack, Clifford R; Jenkinson, Mark; Johnson, Robert; Kanai, Ryota; Keil, Maria; Kent, Jack W; Kochunov, Peter; Kwok, John B; Lawrie, Stephen M; Liu, Xinmin; Longo, Dan L; McMahon, Katie L; Meisenzahl, Eva; Melle, Ingrid; Mohnke, Sebastian; Montgomery, Grant W; Mostert, Jeanette C; Mühleisen, Thomas W; Nalls, Michael A; Nichols, Thomas E; Nilsson, Lars G; Nöthen, Markus M; Ohi, Kazutaka; Olvera, Rene L; Perez-Iglesias, Rocio; Pike, G Bruce; Potkin, Steven G; Reinvang, Ivar; Reppermund, Simone; Rietschel, Marcella; Romanczuk-Seiferth, Nina; Rosen, Glenn D; Rujescu, Dan; Schnell, Knut; Schofield, Peter R; Smith, Colin; Steen, Vidar M; Sussmann, Jessika E; Thalamuthu, Anbupalam; Toga, Arthur W; Traynor, Bryan J; Troncoso, Juan; Turner, Jessica A; Valdés Hernández, Maria C; van 't Ent, Dennis; van der Brug, Marcel; van der Wee, Nic J A; van Tol, Marie-Jose; Veltman, Dick J; Wassink, Thomas H; Westman, Eric; Zielke, Ronald H; Zonderman, Alan B; Ashbrook, David G; Hager, Reinmar; Lu, Lu; McMahon, Francis J; Morris, Derek W; Williams, Robert W; Brunner, Han G; Buckner, Randy L; Buitelaar, Jan K; Cahn, Wiepke; Calhoun, Vince D; Cavalleri, Gianpiero L; Crespo-Facorro, Benedicto; Dale, Anders M; Davies, Gareth E; Delanty, Norman; Depondt, Chantal; Djurovic, Srdjan; Drevets, Wayne C; Espeseth, Thomas; Gollub, Randy L; Ho, Beng-Choon; Hoffmann, Wolfgang; Hosten, Norbert; Kahn, René S; Le Hellard, Stephanie; Meyer-Lindenberg, Andreas; Müller-Myhsok, Bertram; Nauck, Matthias; Nyberg, Lars; Pandolfo, Massimo; Penninx, Brenda W J H; Roffman, Joshua L; Sisodiya, Sanjay M; Smoller, Jordan W; van Bokhoven, Hans; van Haren, Neeltje E M; Völzke, Henry; Walter, Henrik; Weiner, Michael W; Wen, Wei; White, Tonya; Agartz, Ingrid; Andreassen, Ole A; Blangero, John; Boomsma, Dorret I; Brouwer, Rachel M; Cannon, Dara M; Cookson, Mark R; de Geus, Eco J C; Deary, Ian J; Donohoe, Gary; Fernández, Guillén; Fisher, Simon E; Francks, Clyde; Glahn, David C; Grabe, Hans J; Gruber, Oliver; Hardy, John; Hashimoto, Ryota; Hulshoff Pol, Hilleke E; Jönsson, Erik G; Kloszewska, Iwona; Lovestone, Simon; Mattay, Venkata S; Mecocci, Patrizia; McDonald, Colm; McIntosh, Andrew M; Ophoff, Roel A; Paus, Tomas; Pausova, Zdenka; Ryten, Mina; Sachdev, Perminder S; Saykin, Andrew J; Simmons, Andy

    2015-04-01

    The highly complex structure of the human brain is strongly shaped by genetic influences. Subcortical brain regions form circuits with cortical areas to coordinate movement, learning, memory and motivation, and altered circuits can lead to abnormal behaviour and disease. To investigate how common genetic variants affect the structure of these brain regions, here we conduct genome-wide association studies of the volumes of seven subcortical regions and the intracranial volume derived from magnetic resonance images of 30,717 individuals from 50 cohorts. We identify five novel genetic variants influencing the volumes of the putamen and caudate nucleus. We also find stronger evidence for three loci with previously established influences on hippocampal volume and intracranial volume. These variants show specific volumetric effects on brain structures rather than global effects across structures. The strongest effects were found for the putamen, where a novel intergenic locus with replicable influence on volume (rs945270; P = 1.08 × 10(-33); 0.52% variance explained) showed evidence of altering the expression of the KTN1 gene in both brain and blood tissue. Variants influencing putamen volume clustered near developmental genes that regulate apoptosis, axon guidance and vesicle transport. Identification of these genetic variants provides insight into the causes of variability in human brain development, and may help to determine mechanisms of neuropsychiatric dysfunction.

  17. Optogenetic Tools for Confined Stimulation in Deep Brain Structures.

    Science.gov (United States)

    Castonguay, Alexandre; Thomas, Sébastien; Lesage, Frédéric; Casanova, Christian

    2016-01-01

    Optogenetics has emerged in the past decade as a technique to modulate brain activity with cell-type specificity and with high temporal resolution. Among the challenges associated with this technique is the difficulty to target a spatially restricted neuron population. Indeed, light absorption and scattering in biological tissues make it difficult to illuminate a minute volume, especially in the deep brain, without the use of optical fibers to guide light. This work describes the design and the in vivo application of a side-firing optical fiber adequate for delivering light to specific regions within a brain subcortical structure. PMID:26965129

  18. Sex steroids and brain structure in pubertal boys and girls.

    Science.gov (United States)

    Peper, Jiska S; Brouwer, Rachel M; Schnack, Hugo G; van Baal, G Caroline; van Leeuwen, Marieke; van den Berg, Stéphanie M; Delemarre-Van de Waal, Henriëtte A; Boomsma, Dorret I; Kahn, René S; Hulshoff Pol, Hilleke E

    2009-04-01

    Sex steroids exert important organizational effects on brain structure. Early in life, they are involved in brain sexual differentiation. During puberty, sex steroid levels increase considerably. However, to which extent sex steroid production is involved in structural brain development during human puberty remains unknown. The relationship between pubertal rises in testosterone and estradiol levels and brain structure was assessed in 37 boys and 41 girls (10-15 years). Global brain volumes were measured using volumetric-MRI. Regional gray and white matter were quantified with voxel-based morphometry (VBM), a technique which measures relative concentrations ('density') of gray and white matter after individual global differences in size and shape of brains have been removed. Results showed that, corrected for age, global gray matter volume was negatively associated with estradiol levels in girls, and positively with testosterone levels in boys. Regionally, a higher estradiol level in girls was associated with decreases within prefrontal, parietal and middle temporal areas (corrected for age), and with increases in middle frontal-, inferior temporal- and middle occipital gyri. In boys, estradiol and testosterone levels were not related to regional brain structures, nor were testosterone levels in girls. Pubertal sex steroid levels could not explain regional sex differences in regional gray matter density. Boys were significantly younger than girls, which may explain part of the results. In conclusion, in girls, with the progression of puberty, gray matter development is at least in part directly associated with increased levels of estradiol, whereas in boys, who are in a less advanced pubertal stage, such steroid-related development could not (yet) be found. We suggest that in pubertal girls, estradiol may be implicated in neuronal changes in the cerebral cortex during this important period of brain development.

  19. Use case: Ontology with rules for identifying brain anatomical structures

    OpenAIRE

    Golbreich, Christine; Bierlaire, Olivier; Dameron, Olivier; Gibaud, Bernard

    2005-01-01

    International audience The proposed use case focuses on interoperating between a rule base and a brain cortex anatomy ontology, in order to assist the labeling of the brain cortex structures - sulci and gyri - involved in MRI images. The use case documents the ontology and the rules so as to clarify the added value and needs of rules, and the language expressiveness required. The expected result is to get candidate languages extending OWL DL with rules that allow representing all the knowl...

  20. Diffusion-weighted imaging of brain injury due to neonatal hypoglycemia: a case report

    International Nuclear Information System (INIS)

    Profound hypoglycemia results in significant brain injury because glucose is essential for normal brain functioning. We present here a case of transient neonatal hypoglycemia with diffuse brain injury. Magnetic resonance imaging was performed 2 days after onset, and this revealed bilateral regions of restricted diffusion in the parietal, occipital, frontal and temporal lobes. On the T1-weighted images, the regions showed indistinct gray matter-white matter differentiation. There were subtle high signal intensity lesions along the corresponding regions of the FLAIR and T2-weighted images

  1. Diffusion-weighted imaging of brain injury due to neonatal hypoglycemia: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Eun A; Choi, See Sung; Jeon, Se Jeong; Kim, Eun A; Lee, Young Hwan; Juhng, Seon Kwan [Wonkwang University Hospital, Iksan (Korea, Republic of)

    2006-10-15

    Profound hypoglycemia results in significant brain injury because glucose is essential for normal brain functioning. We present here a case of transient neonatal hypoglycemia with diffuse brain injury. Magnetic resonance imaging was performed 2 days after onset, and this revealed bilateral regions of restricted diffusion in the parietal, occipital, frontal and temporal lobes. On the T1-weighted images, the regions showed indistinct gray matter-white matter differentiation. There were subtle high signal intensity lesions along the corresponding regions of the FLAIR and T2-weighted images.

  2. [The efficacy of botulinum toxin therapy in patients with upper limb spasticity due to traumatic brain injury].

    Science.gov (United States)

    Akulov, M A; Khat'kova, S E; Mokienko, O A; Orlova, O R; Usachev, D Yu; Zakharov, V O; Orlova, A S; Tomsky, A A

    2016-01-01

    Spasticity is a type of muscle hyperactivity that occurs in patients after focal lesions of the Central nervous system due to various diseases: stroke, traumatic brain injury or spinal cord injury, neurosurgical intervention, as well as multiple sclerosis and other diseases of the Central nervous system and is the most disability manifestation of the syndrome of upper motor neuron (UMNS). Focal spasticity of the upper limb requires a complex treatment. Botulinum toxin therapy is an effective treatment for focal/multifocal spasticity in reducing muscle tone and improving function with the highest level of evidence according to the latest American and European guidelines for treatment of spasticity. There are many publications devoted to BTA use in post-stroke patients. This article provides a review of the BTA use in patients with the upper limb spasticity due to severe traumatic brain injury. Some local data on the BTA efficacy in the cohort of patients with traumatic brain injury are also presented. PMID:27635608

  3. Cocaine postmortem distribution in three brain structures: a comparison with whole blood and vitreous humour.

    Science.gov (United States)

    Carvalho, Virginia M; Fukushima, André R; Fontes, Luiz R; Fuzinato, Daniela V; Florio, Jorge C; Chasin, Alice A M

    2013-04-01

    The presence of cocaine (COC) in fluids or tissues does not prove that death was due to drug consumption and the interpretation of postmortem concentrations is more complex than attempts at making such correlations in the living. The purpose of this study was to investigate the distribution of cocaine and its metabolite benzoylecgonine in brain and compare with whole blood and vitreous humour. The distribution in three brain structures (prefrontal cortex, basal ganglia and cerebellum) was homogeneous. There is a strong correlation for cocaine concentrations between vitreous humour and brain, vitreous humour and whole blood, and whole blood and brain in overdose cases. In addition, the comparison of COC/benzoylecgonine (BE) ratios in different experimental specimens proved to be more appropriate for evaluating cocaine-related death than individual drug values. These findings suggest that the comparison of cocaine levels in different compartments is essential to assess the cause of death. PMID:23472791

  4. Destruction of the resins structure due to heating

    Directory of Open Access Journals (Sweden)

    Bakhtizin Ramil Nazifovich

    2015-06-01

    Full Text Available This article considers a polymer composition based on acetone-formaldehyde (AFR resin, which is used to reduce water influx into the well bore during the repair insulation work. Pumping into the well bore a composition, based on AFR resin, results in self-heating that causes destruction of its own structure and, therefore, the damage of the polymer blend structure. The purpose of the present article is to find the causes of AFR resin self-heating when injected into the well bore as part of the composite mixture that leads to the destruction of its structure. Author considers exothermic reaction between AFR resin and aqueous solution of sodium hydroxide during the curing of the polymer composition. The features of the given polymer structure are studied as well. The need for further studies of the resin structure is substantiated. Based on the study conducted, five possible reasons of the AFR resin self-heating, leading to destruction of resin structure, are revealed. Recommended practices that may decrease self-heating of the AFR resin are offered.

  5. Physical exercise in overweight to obese individuals induces metabolic- and neurotrophic-related structural brain plasticity

    Science.gov (United States)

    Mueller, Karsten; Möller, Harald E.; Horstmann, Annette; Busse, Franziska; Lepsien, Jöran; Blüher, Matthias; Stumvoll, Michael; Villringer, Arno; Pleger, Burkhard

    2015-01-01

    Previous cross-sectional studies on body-weight-related alterations in brain structure revealed profound changes in the gray matter (GM) and white matter (WM) that resemble findings obtained from individuals with advancing age. This suggests that obesity may lead to structural brain changes that are comparable with brain aging. Here, we asked whether weight-loss-dependent improved metabolic and neurotrophic functioning parallels the reversal of obesity-related alterations in brain structure. To this end we applied magnetic resonance imaging (MRI) together with voxel-based morphometry and diffusion-tensor imaging in overweight to obese individuals who participated in a fitness course with intensive physical training twice a week over a period of 3 months. After the fitness course, participants presented, with inter-individual heterogeneity, a reduced body mass index (BMI), reduced serum leptin concentrations, elevated high-density lipoprotein-cholesterol (HDL-C), and alterations of serum brain-derived neurotrophic factor (BDNF) concentrations suggesting changes of metabolic and neurotrophic function. Exercise-dependent changes in BMI and serum concentration of BDNF, leptin, and HDL-C were related to an increase in GM density in the left hippocampus, the insular cortex, and the left cerebellar lobule. We also observed exercise-dependent changes of diffusivity parameters in surrounding WM structures as well as in the corpus callosum. These findings suggest that weight-loss due to physical exercise in overweight to obese participants induces profound structural brain plasticity, not primarily of sensorimotor brain regions involved in physical exercise, but of regions previously reported to be structurally affected by an increased body weight and functionally implemented in gustation and cognitive processing. PMID:26190989

  6. Physical exercise in overweight to obese individuals induces metabolic- and neurotrophic-related structural brain plasticity

    Directory of Open Access Journals (Sweden)

    Karsten eMueller

    2015-07-01

    Full Text Available Previous cross-sectional studies on body-weight-related alterations in brain structure revealed profound changes in the gray matter (GM and white matter (WM that resemble findings obtained from individuals with advancing age. This suggests that obesity may lead to structural brain changes that are comparable with brain aging. Here, we asked whether weight-loss-dependent improved metabolic and neurotrophic functioning parallels the reversal of obesity-related alterations in brain structure. To this end we applied magnetic resonance imaging together with voxel-based morphometry and diffusion-tensor imaging in overweight to obese individuals who participated in a fitness course with intensive physical training three days per week over a period of three months. After the fitness course, participants presented, with inter-individual heterogeneity, a reduced body mass index (BMI, reduced serum leptin concentrations, elevated high-density lipoprotein-cholesterol (HDL-C, and alterations of serum brain-derived neurotrophic factor (BDNF concentrations suggesting changes of metabolic and neurotrophic function. Exercise-dependent changes in BMI and serum concentration of BDNF, leptin, and HDL-C were related to an increase in GM density in the left hippocampus, the insular cortex, and the left cerebellar lobule. We also observed exercise-dependent changes of diffusivity parameters in surrounding WM structures as well as in the corpus callosum. These findings suggest that weight-loss due to physical exercise in overweight to obese participants induces profound structural brain plasticity, not primarily of sensorimotor brain regions involved in physical exercise, but of regions previously reported to be structurally affected by an increased body weight and functionally implemented in gustation and cognitive processing.

  7. Preterm birth and structural brain alterations in early adulthood

    Directory of Open Access Journals (Sweden)

    Chiara Nosarti

    2014-01-01

    callosum/thalamus/fornix and GM volume in temporal gyri bilaterally, accounted for 21% of the variance of executive function (F = 9.9, p < 0.0001 and WM in the posterior corpus callosum/thalamus/fornix alone accounted for 17% of the variance of total non-verbal memory scores (F = 9.9, p < 0.0001. These results reveal that VPT birth continues to be associated with altered structural brain anatomy in early adult life, although it remains to be ascertained whether these changes reflect neurodevelopmental delays or long lasting structural alterations due to prematurity. GM and WM alterations correlate with length of gestation and mediate cognitive outcome.

  8. Atlas based brain volumetry: How to distinguish regional volume changes due to biological or physiological effects from inherent noise of the methodology.

    Science.gov (United States)

    Opfer, Roland; Suppa, Per; Kepp, Timo; Spies, Lothar; Schippling, Sven; Huppertz, Hans-Jürgen

    2016-05-01

    Fully-automated regional brain volumetry based on structural magnetic resonance imaging (MRI) plays an important role in quantitative neuroimaging. In clinical trials as well as in clinical routine multiple MRIs of individual patients at different time points need to be assessed longitudinally. Measures of inter- and intrascanner variability are crucial to understand the intrinsic variability of the method and to distinguish volume changes due to biological or physiological effects from inherent noise of the methodology. To measure regional brain volumes an atlas based volumetry (ABV) approach was deployed using a highly elastic registration framework and an anatomical atlas in a well-defined template space. We assessed inter- and intrascanner variability of the method in 51 cognitively normal subjects and 27 Alzheimer dementia (AD) patients from the Alzheimer's Disease Neuroimaging Initiative by studying volumetric results of repeated scans for 17 compartments and brain regions. Median percentage volume differences of scan-rescans from the same scanner ranged from 0.24% (whole brain parenchyma in healthy subjects) to 1.73% (occipital lobe white matter in AD), with generally higher differences in AD patients as compared to normal subjects (e.g., 1.01% vs. 0.78% for the hippocampus). Minimum percentage volume differences detectable with an error probability of 5% were in the one-digit percentage range for almost all structures investigated, with most of them being below 5%. Intrascanner variability was independent of magnetic field strength. The median interscanner variability was up to ten times higher than the intrascanner variability.

  9. Analysis of soil-structure interaction due to ambient vibration

    Energy Technology Data Exchange (ETDEWEB)

    Tabatabaie, M., Sommer, S.C.

    1998-03-27

    This paper presents the results of a study to evaluate the effects of soil-structure interaction (SSI) on the ambient vibration response of the switchyard/target area (S/TA) buildings at the National Ignition Facility (NIF) presently under construction at the Lawrence Livermore National Laboratory (LLNL) in Livermore, California. This laser facility houses optical and other special equipment whose alignment stability is sensitive to vibrations caused by ambient vibrations or other vibrating sources. In evaluating the deformations and displacements of the S/TA structures, the contribution of the SSI to the overall system flexibility can be very significant. The present study examines the results of fixed-base and SSI analyses of these massive stiff structures to develop an understanding of the potential contribution of SSI to the overall system displacements and deformations. A simple procedure using a set of factors is recommended for scaling the results of fixed-base analyses to approximately account for SSI effects.

  10. Impact of metal artefacts due to EEG electrodes in brain PET/CT imaging

    International Nuclear Information System (INIS)

    The goal of this study is to investigate the impact of electroencephalogram (EEG) electrodes on the visual quality and quantification of 18F-FDG PET images in neurological PET/CT examinations. For this purpose, the scans of 20 epilepsy patients with EEG monitoring were used. The CT data were reconstructed with filtered backprojection (FBP) and with a metal artefact reduction (MAR) algorithm. Both data sets were used for CT-based attenuation correction (AC) of the PET data. Also, a calculated AC (CALC) technique was considered. A volume of interest (VOI)-based analysis and a voxel-based quantitative analysis were performed to compare the different AC methods. Images were also evaluated visually by two observers. It was shown with simulations and phantom measurements that from the considered AC methods, the MAR-AC can be used as the reference in this setting. The visual assessment of PET images showed local hot spots outside the brain corresponding to the locations of the electrodes when using FBP-AC. In the brain, no abnormalities were observed. The quantitative analysis showed a very good correlation between PET-FBP-AC and PET-MAR-AC, with a statistically significant positive bias in the PET-FBP-AC images of about 5-7% in most brain voxels. There was also good correlation between PET-CALC-AC and PET-MAR-AC, but in the PET-CALC-AC images, regions with both a significant positive and negative bias were observed. EEG electrodes give rise to local hot spots outside the brain and a positive quantification bias in the brain. However, when diagnosis is made by mere visual assessment, the presence of EEG electrodes does not seem to alter the diagnosis. When quantification is performed, the bias becomes an issue especially when comparing brain images with and without EEG monitoring

  11. A New Strategy of Drug Delivery: Electric Field Distribution in Brain Tumor Due to Electroporation

    OpenAIRE

    Shi, Junxing

    2014-01-01

    As the second leading cause of cancer-related deaths in children under 20, and the second leading cause of cancer-related deaths in males aged 20–39, there is a need to seek an effective treatment for brain tumors. While there may be various drugs for brain tumors, the problem is the lack of effective methods of delivery through cell membranes at a very specified and confined region. In order to tackle this specific problem of drug delivery, electroporation is introduced. Electroporation, the...

  12. Selective value of computed tomography of the brain in Cerebritis due to systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Gaylis, N.B.; Altman, R.D.; Ostrov, S.; Quencer, R. (Miami Univ., FL (USA). School of Medicine)

    Systemic lupus erythematosus (SLE) and steroid effects on the brain were measured by computed tomography (CT). Of 14 patients with SLE cerebritis, 10 (71%) had marked cortical atrophy and 4 (29%) minimal atrophy. None were normal by CT. Controls included 22 patients with SLE without cerebritis receiving cortiocosteroids; this group had normal CT scans in 16 (73%) and minimal cortical atrophy in the remaining 6 (27%). Follow-up CT on 5 patients with cerebritis was unchanged. CT of the brain is a minimally invasive technique for documenting SLE cerebritis. CT may also help differentiate cerebritis from the neuropsychiatric side effects of corticosteroids.

  13. The selective value of computed tomography of the brain in Cerebritis due to systemic lupus erythematosus

    International Nuclear Information System (INIS)

    Systemic lupus erythematosus (SLE) and steroid effects on the brain were measured by computed tomography (CT). Of 14 patients with SLE cerebritis, 10 (71%) had marked cortical atrophy and 4 (29%) minimal atrophy. None were normal by CT. Controls included 22 patients with SLE without cerebritis receiving cortiocosteroids; this group had normal CT scans in 16 (73%) and minimal cortical atrophy in the remaining 6 (27%). Follow-up CT on 5 patients with cerebritis was unchanged. CT of the brain is a minimally invasive technique for documenting SLE cerebritis. CT may also help differentiate cerebritis from the neuropsychiatric side effects of corticosteroids

  14. Unusual resonances in nanoplasmonic structures due to nonlocal response

    DEFF Research Database (Denmark)

    Raza, Søren; Toscano, Giuseppe; Jauho, Antti-Pekka;

    2011-01-01

    find that such resonances do indeed occur, but only above the plasma frequency. Thus the recently found nonlocal resonances at optical frequencies for very small structures, obtained within quasistatic approximation, are unphysical. As a specific example we consider nanosized metallic cylinders, for...

  15. Effects of prenatal cocaine exposure on early postnatal rodent brain structure and diffusion properties.

    Science.gov (United States)

    McMurray, Matthew S; Oguz, Ipek; Rumple, Ashley M; Paniagua, Beatriz; Styner, Martin A; Johns, Josephine M

    2015-01-01

    Prenatal cocaine exposure has been associated with numerous behavioral phenotypes in clinical populations, including impulsivity, reduced attention, alterations in social behaviors, and delayed language and sensory-motor development. Detecting associated changes in brain structure in these populations has proven difficult, and results have been inconclusive and inconsistent. Due to their more controlled designs, animal models may shed light on the neuroanatomical changes caused by prenatal cocaine; however, to maximize clinical relevance, data must be carefully collected using translational methods. The goal of this study was two-fold: (1) to determine if prenatal cocaine alters developmental neuroanatomy using methods that are available to human researchers, specifically structural MRI and diffusion tensor imaging, and (2) to determine the feasibility of rodent in vivo neuroimaging for usage in longitudinal studies of developmental disorders. Cocaine-exposed (prenatal days 1-20, 30mg/kg/day) rat pups were sedated and imaged live using diffusion tensor imaging and postmortem (fixed) using magnetic resonance histology on postnatal day 14. Volume and diffusion properties in whole brain as well as specific regions of interest were then assessed from the resulting images. Whole brain analyses revealed that cocaine-exposed animals showed no change in whole brain volume. Additionally, we found alterations in fractional anisotropy across regions associated with reward processing and emotional regulation, especially in the thalamus and globus pallidus, as well as sex-dependent effects of cocaine in the right cortex. Reductions in fractional anisotropy were paired with reductions only in axial diffusivity, which preliminarily suggests that the changes observed here may be due to axonal damage, as opposed to reductions in myelination of the affected regions/pathways. Our data indicate that prenatal cocaine may target a number of developing brain structures but does not

  16. Internal radiation absorbed dose estimation in human brain due to technetium-99m and iodine-131

    International Nuclear Information System (INIS)

    Internal dosimetry is a branch of medical physics that deals with the measurement of the internally absorbed dose by an organ after applying isotopes. In this study, internal radiation absorbed dose has been calculated for 99mTc and 131I, which are frequently used for functioning tests and therapeutic treatments of thyroid, respectively in these cases, some amount of isotopes are accumulated in other tissues like brain, which are very soft and cannot be regenerated if they are damaged. Using ionizing radiation inside the body and to ensure the safety of brain, the internal radiation absorbed dose has been calculated applying direct counting measurement. Accumulation of isotopes to target organ has been measured and this target organ is considered as primary target organ; also this organ is considered as source with respect to other organs. These organ counts have, been measured by computer-based scintillation system. The amount of exposure in brain has been measured with the help of the data obtained from the special set-up equipment, including NaI detector, radiation survey meter and water phantoms of various sizes. Absorbed dose in brain for each isotope has been calculated by applying time-activity curve analysis. Finally, these results have been compared with the data in ICRP l Reports 53 and 71. (author)

  17. Toll-like receptor 4 knockout ameliorates neuroinflammation due to lung-brain interaction in mechanically ventilated mice.

    Science.gov (United States)

    Chen, Ting; Chen, Chang; Zhang, Zongze; Zou, Yufeng; Peng, Mian; Wang, Yanlin

    2016-08-01

    Toll-like receptor 4 (TLR4) is a crucial receptor in the innate immune system, and increasing evidence supports its role in inflammation, stress, and tissue injury, including injury to the lung and brain. We aimed to investigate the effects of TLR4 on neuroinflammation due to the lung-brain interaction in mechanically ventilated mice. Male wild-type (WT) C57BL/6 and TLR4 knockout (TLR4 KO) mice were divided into three groups: (1) control group (C): spontaneous breathing; (2) anesthesia group (A): spontaneous breathing under anesthesia; and (3) mechanical ventilation group (MV): 6h of MV under anesthesia. The behavioral responses of mice were tested with fear conditioning tests. The histological changes in the lung and brain were assessed using hematoxylin-eosin (HE) staining. The level of TLR4 mRNA in tissue was measured using reverse transcription-polymerase chain reaction (RT-PCR). The levels of inflammatory cytokines were measured with an enzyme-linked immunosorbent assay (ELISA). Microgliosis, astrocytosis, and the TLR4 immunoreactivity in the hippocampus were measured by double immunofluorescence. MV mice exhibited impaired cognition, and this impairment was less severe in TLR4 KO mice than in WT mice. In WT mice, MV increased TLR4 mRNA expression in the lung and brain. MV induced mild lung injury, which was prevented in TLR4 KO mice. MV mice exhibited increased levels of inflammatory cytokines, increased microglia and astrocyte activation. Microgliosis was alleviated in TLR4 KO mice. MV mice exhibited increased TLR4 immunoreactivity, which was expressed in microglia and astrocytes. These results demonstrate that TLR4 is involved in neuroinflammation due to the lung-brain interaction and that TLR4 KO ameliorates neuroinflammation due to lung-brain interaction after prolonged MV. In addition, Administration of a TLR4 antagonist (100μg/mice) to WT mice also significantly attenuated neuroinflammation of lung-brain interaction due to prolonged MV. TLR4 antagonism

  18. Food Web Structure Shapes the Morphology of Teleost Fish Brains.

    Science.gov (United States)

    Edmunds, Nicholas B; McCann, Kevin S; Laberge, Frédéric

    2016-01-01

    Previous work showed that teleost fish brain size correlates with the flexible exploitation of habitats and predation abilities in an aquatic food web. Since it is unclear how regional brain changes contribute to these relationships, we quantitatively examined the effects of common food web attributes on the size of five brain regions in teleost fish at both within-species (plasticity or natural variation) and between-species (evolution) scales. Our results indicate that brain morphology is influenced by habitat use and trophic position, but not by the degree of littoral-pelagic habitat coupling, despite the fact that the total brain size was previously shown to increase with habitat coupling in Lake Huron. Intriguingly, the results revealed two potential evolutionary trade-offs: (i) relative olfactory bulb size increased, while relative optic tectum size decreased, across a trophic position gradient, and (ii) the telencephalon was relatively larger in fish using more littoral-based carbon, while the cerebellum was relatively larger in fish using more pelagic-based carbon. Additionally, evidence for a within-species effect on the telencephalon was found, where it increased in size with trophic position. Collectively, these results suggest that food web structure has fundamentally contributed to the shaping of teleost brain morphology. PMID:27216606

  19. Food Web Structure Shapes the Morphology of Teleost Fish Brains.

    Science.gov (United States)

    Edmunds, Nicholas B; McCann, Kevin S; Laberge, Frédéric

    2016-01-01

    Previous work showed that teleost fish brain size correlates with the flexible exploitation of habitats and predation abilities in an aquatic food web. Since it is unclear how regional brain changes contribute to these relationships, we quantitatively examined the effects of common food web attributes on the size of five brain regions in teleost fish at both within-species (plasticity or natural variation) and between-species (evolution) scales. Our results indicate that brain morphology is influenced by habitat use and trophic position, but not by the degree of littoral-pelagic habitat coupling, despite the fact that the total brain size was previously shown to increase with habitat coupling in Lake Huron. Intriguingly, the results revealed two potential evolutionary trade-offs: (i) relative olfactory bulb size increased, while relative optic tectum size decreased, across a trophic position gradient, and (ii) the telencephalon was relatively larger in fish using more littoral-based carbon, while the cerebellum was relatively larger in fish using more pelagic-based carbon. Additionally, evidence for a within-species effect on the telencephalon was found, where it increased in size with trophic position. Collectively, these results suggest that food web structure has fundamentally contributed to the shaping of teleost brain morphology.

  20. Cognitive Abilities Independent of IQ Correlate with Regional Brain Structure

    Science.gov (United States)

    Johnson, Wendy; Jung, Rex E.; Colom, Roberto; Haier, Richard J.

    2008-01-01

    There is increasing evidence relating psychometric measures of general intelligence and reasoning to regional brain structure and function assessed with a variety of neuroimaging techniques. Cognitive dimensions independent of general intelligence can also be identified psychometrically and studied for any neuroanatomical correlates. Here we…

  1. Optical loss due to intrinsic structural variations of photonic crystals

    CERN Document Server

    Koenderink, A F; Vos, Willem L.

    2004-01-01

    A bottleneck limiting the widespread application of photonic crystals is scattering of light by unavoidable variations in size and position of the crystals' building blocks. We present a new model for both 2 and 3-dimensional photonic crystals that relates the resulting loss length to the magnitude of the variations. The predicted lengths agree well with our experiments on high-quality opals and inverse opals over a wide frequency range, and with literature data analyzed by us. In state-of-the-art structures, control over photons is limited to distances of 50 lattice parameters (~ 15 micron). Consequently, applications of photonic crystals in optical integrated circuits remain a fata morgana, unless an unprecedented reduction of the random variations is achieved.

  2. Fluid transport due to nonlinear fluid-structure interaction

    Energy Technology Data Exchange (ETDEWEB)

    Soendergaard Jensen, J.

    1996-08-01

    This work considers nonlinear fluid-structure interaction for a vibrating pipe containing fluid. Transverse pipe vibrations will force the fluid to move relative to the pipe creating uni-directional fluid flow towards the pipe end. The fluid flow induced affects the damping and the stiffness of the pipe. The behavior of the system in response to lateral resonant base excitation is analyzed numerically mode of vibration seems to be most effective for high mean fluid speed, whereas higher modes of vibration can be used to transport fluid with the same fluid speed but with smaller magnitude of pipe vibrations. The effect of the nonlinear geometrical terms is analyzed and these terms are shown to affect the response for higher modes of vibration. Experimental investigations show good agreement with theoretical predictions. (au) 16 refs.

  3. Brillouin resonance broadening due to structural variations in nanoscale waveguides

    CERN Document Server

    Wolff, Christian; Steel, Michael J; Eggleton, Benjamin J; Poulton, Christopher G

    2015-01-01

    We study the impact of structural variations (that is slowly varying geometry aberrations and internal strain fields) on the resonance width and shape of stimulated Brillouin scattering (SBS) in nanoscale waveguides. We find that they lead to an inhomogeneous resonance broadening through two distinct mechanisms: firstly, the acoustic frequency is directly influenced via mechanical nonlinearities; secondly, the optical wave numbers are influenced via the opto-mechanical nonlinearity leading to an additional acoustic frequency shift via the phase-matching condition. We find that this second mechanism is proportional to the opto-mechanical coupling and, hence, related to the SBS-gain itself. It is absent in intra-mode forward SBS, while it plays a significant role in backward scattering. In backward SBS increasing the opto-acoustic overlap beyond a threshold defined by the fabrication tolerances will therefore no longer yield the expected quadratic increase in overall Stokes amplification. Our results can be tra...

  4. Structural expression of forearc crust uplift due to subducting asperity

    Science.gov (United States)

    Fleury, Jean-Marc; Pubellier, Manuel; de Urreiztieta, Marc

    2009-12-01

    New structural observations and mapping of reefal terraces, carried out both on the field and on satellite remote sensing data, indicate that Sumba Island is presently undergoing a large amount of extension, associated with a significant regional uplift. This crustal uplift may have been created by a major thrust emerging in the South of the island. The uplift, which partly accommodated the Australian plate-South West Banda Arc convergence, is associated with the general northeastward tilt of the island. The consequent anomalous positive topography along the southern coast of the island is being compensated by significant tectonic erosion along large-scale curvilinear normal faults in the southeastern half of the island. The most important expression of this gravitational collapse is located at the receding side of an advancing circular dome, showing striking similarities with accretionary wedges being affected by seamount subduction. The part of the forearc basin known as the Savu Basin is moderately deformed (mostly in its central part) and appears to act as a rigid buttress in the convergence between the Banda Arc and the Australian plate. As a result the convergence appears to be transferred northward within the actively-shortening back-arc domain, which goes from the north of the Flores Island to the southwest of the Timor block. The convergent plate boundary shows a transition between a stable domain (West of Sumba) and a tectonized domain (East of Sumba), the latter coinciding with the subduction of the outer Australian passive margin. The subduction of the ocean-continent boundary of the Austral-Indian plate below the Banda arc since the Lower Pliocene may have incorporated some crustal fragments in the plunging Benioff zone. Most likely, the integration of the stretched continental lithosphere in the subduction zone caused the uplift the entire forearc domain, exhibiting inherited structures of the upper plate.

  5. Prevention and Treatment of Traumatic Brain Injury Due to Rapid-Onset Natural Disasters

    OpenAIRE

    Regens, James L.; Mould, Nick

    2014-01-01

    The prevention and treatment of traumatic brain injury (TBI) attributable to rapid-onset natural disasters is a major challenge confronting disaster preparedness planners and emergency medical personnel responding to those incidents. The kinetic energy released by rapid-onset natural disasters such as earthquakes, hurricanes or typhoons, and tornadoes can cause mild, moderate, or severe TBIs. As a result, neurotrauma is a major risk factor for mortality and morbidity outcomes within the spati...

  6. Role of MicroRNAs in innate neuroprotection mechanisms due to preconditioning of the brain

    Directory of Open Access Journals (Sweden)

    Eva Maria Jimenez-Mateos

    2015-04-01

    Full Text Available Insults to the brain that are sub-threshold for damage activate endogenous protective pathways, which can temporarily protect the brain against a subsequent harmful episode. This mechanism has been named as tolerance and its protective effects have been shown in experimental models of ischemia and epilepsy. The preconditioning-stimulus can be a short period of ischemia or mild seizures induced by low doses of convulsant drugs.Gene-array profiling has shown that both ischemic and epileptic tolerance feature large-scale gene down-regulation but the mechanism are unknown. MicroRNAs are a class of small non-coding RNAs of ~20-22 nucleotides length which regulate gene expression at a post-transcriptional level via mRNA degradation or inhibition of protein translation. MicroRNAs have been shown to be regulated after non-harmful and harmful stimuli in the brain and to contribute to neuroprotective mechanisms. This review focuses on the role of microRNAs in the development of tolerance following ischemic or epileptic preconditioning.

  7. Brain Functional and Structural Predictors of Language Performance.

    Science.gov (United States)

    Skeide, Michael A; Brauer, Jens; Friederici, Angela D

    2016-05-01

    The relation between brain function and behavior on the one hand and the relation between structural changes and behavior on the other as well as the link between the 2 aspects are core issues in cognitive neuroscience. It is an open question, however, whether brain function or brain structure is the better predictor for age-specific cognitive performance. Here, in a comprehensive set of analyses, we investigated the direct relation between hemodynamic activity in 2 pairs of frontal and temporal cortical areas, 2 long-distance white matter fiber tracts connecting each pair and sentence comprehension performance of 4 age groups, including 3 groups of children between 3 and 10 years as well as young adults. We show that the increasing accuracy of processing complex sentences throughout development is correlated with the blood-oxygen-level-dependent activation of 2 core language processing regions in Broca's area and the posterior portion of the superior temporal gyrus. Moreover, both accuracy and speed of processing are correlated with the maturational status of the arcuate fasciculus, that is, the dorsal white matter fiber bundle connecting these 2 regions. The present data provide compelling evidence for the view that brain function and white matter structure together best predict developing cognitive performance. PMID:25770126

  8. Training-induced brain structure changes in the elderly.

    Science.gov (United States)

    Boyke, Janina; Driemeyer, Joenna; Gaser, Christian; Büchel, Christian; May, Arne

    2008-07-01

    It has been suggested that learning is associated with a transient and highly selective increase in brain gray matter in healthy young volunteers. It is not clear whether and to what extent the aging brain is still able to exhibit such structural plasticity. We built on our original study, now focusing on healthy senior citizens. We observed that elderly persons were able to learn three-ball cascade juggling, but with less proficiency compared with 20-year-old adolescents. Similar to the young group, gray-matter changes in the older brain related to skill acquisition were observed in area hMT/V5 (middle temporal area of the visual cortex). In addition, elderly volunteers who learned to juggle showed transient increases in gray matter in the hippocampus on the left side and in the nucleus accumbens bilaterally. PMID:18614670

  9. Structural and Functional Plasticity in the Maternal Brain Circuitry.

    Science.gov (United States)

    Pereira, Mariana

    2016-09-01

    Parenting recruits a distributed network of brain structures (and neuromodulators) that coordinates caregiving responses attuned to the young's affect, needs, and developmental stage. Many of these structures and connections undergo significant structural and functional plasticity, mediated by the interplay between maternal hormones and social experience while the reciprocal relationship between the mother and her infant forms and develops. These alterations account for the remarkable behavioral plasticity of mothers. This review will examine the molecular and neurobiological modulation and plasticity through which parenting develops and adjusts in new mothers, primarily discussing recent findings in nonhuman animals. A better understanding of how parenting impacts the brain at the molecular, cellular, systems/network, and behavioral levels is likely to significantly contribute to novel strategies for treating postpartum neuropsychiatric disorders in new mothers, and critical for both the mother's physiological and mental health and the development and well-being of her young. PMID:27589496

  10. Resolving structural variability in network models and the brain.

    Directory of Open Access Journals (Sweden)

    Florian Klimm

    2014-03-01

    Full Text Available Large-scale white matter pathways crisscrossing the cortex create a complex pattern of connectivity that underlies human cognitive function. Generative mechanisms for this architecture have been difficult to identify in part because little is known in general about mechanistic drivers of structured networks. Here we contrast network properties derived from diffusion spectrum imaging data of the human brain with 13 synthetic network models chosen to probe the roles of physical network embedding and temporal network growth. We characterize both the empirical and synthetic networks using familiar graph metrics, but presented here in a more complete statistical form, as scatter plots and distributions, to reveal the full range of variability of each measure across scales in the network. We focus specifically on the degree distribution, degree assortativity, hierarchy, topological Rentian scaling, and topological fractal scaling--in addition to several summary statistics, including the mean clustering coefficient, the shortest path-length, and the network diameter. The models are investigated in a progressive, branching sequence, aimed at capturing different elements thought to be important in the brain, and range from simple random and regular networks, to models that incorporate specific growth rules and constraints. We find that synthetic models that constrain the network nodes to be physically embedded in anatomical brain regions tend to produce distributions that are most similar to the corresponding measurements for the brain. We also find that network models hardcoded to display one network property (e.g., assortativity do not in general simultaneously display a second (e.g., hierarchy. This relative independence of network properties suggests that multiple neurobiological mechanisms might be at play in the development of human brain network architecture. Together, the network models that we develop and employ provide a potentially useful

  11. A Review of the Status of Brain Structure Research in Transsexualism.

    Science.gov (United States)

    Guillamon, Antonio; Junque, Carme; Gómez-Gil, Esther

    2016-10-01

    The present review focuses on the brain structure of male-to-female (MtF) and female-to-male (FtM) homosexual transsexuals before and after cross-sex hormone treatment as shown by in vivo neuroimaging techniques. Cortical thickness and diffusion tensor imaging studies suggest that the brain of MtFs presents complex mixtures of masculine, feminine, and demasculinized regions, while FtMs show feminine, masculine, and defeminized regions. Consequently, the specific brain phenotypes proposed for MtFs and FtMs differ from those of both heterosexual males and females. These phenotypes have theoretical implications for brain intersexuality, asymmetry, and body perception in transsexuals as well as for Blanchard's hypothesis on sexual orientation in homosexual MtFs. Falling within the aegis of the neurohormonal theory of sex differences, we hypothesize that cortical differences between homosexual MtFs and FtMs and male and female controls are due to differently timed cortical thinning in different regions for each group. Cross-sex hormone studies have reported marked effects of the treatment on MtF and FtM brains. Their results are used to discuss the early postmortem histological studies of the MtF brain. PMID:27255307

  12. Neurolinguistics: Structure, Function, and Connectivity in the Bilingual Brain

    Directory of Open Access Journals (Sweden)

    Becky Wong

    2016-01-01

    Full Text Available Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1 whether the language neural network is different for first (dominant versus second (nondominant language processing; (2 the effects of bilinguals’ executive functioning on the structure and function of the “universal” language neural network; (3 the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4 the effects of age of acquisition and proficiency of the user’s second language in the bilingual brain, and how these have implications for future research in neurolinguistics.

  13. Neurolinguistics: Structure, Function, and Connectivity in the Bilingual Brain.

    Science.gov (United States)

    Wong, Becky; Yin, Bin; O'Brien, Beth

    2016-01-01

    Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1) whether the language neural network is different for first (dominant) versus second (nondominant) language processing; (2) the effects of bilinguals' executive functioning on the structure and function of the "universal" language neural network; (3) the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4) the effects of age of acquisition and proficiency of the user's second language in the bilingual brain, and how these have implications for future research in neurolinguistics.

  14. Neurolinguistics: Structure, Function, and Connectivity in the Bilingual Brain.

    Science.gov (United States)

    Wong, Becky; Yin, Bin; O'Brien, Beth

    2016-01-01

    Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1) whether the language neural network is different for first (dominant) versus second (nondominant) language processing; (2) the effects of bilinguals' executive functioning on the structure and function of the "universal" language neural network; (3) the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4) the effects of age of acquisition and proficiency of the user's second language in the bilingual brain, and how these have implications for future research in neurolinguistics. PMID:26881224

  15. Prenatal cocaine effects on brain structure in early infancy.

    Science.gov (United States)

    Grewen, Karen; Burchinal, Margaret; Vachet, Clement; Gouttard, Sylvain; Gilmore, John H; Lin, Weili; Johns, Josephine; Elam, Mala; Gerig, Guido

    2014-11-01

    Prenatal cocaine exposure (PCE) is related to subtle deficits in cognitive and behavioral function in infancy, childhood and adolescence. Very little is known about the effects of in utero PCE on early brain development that may contribute to these impairments. The purpose of this study was to examine brain structural differences in infants with and without PCE. We conducted MRI scans of newborns (mean age = 5 weeks) to determine cocaine's impact on early brain structural development. Subjects were three groups of infants: 33 with PCE co-morbid with other drugs, 46 drug-free controls and 40 with prenatal exposure to other drugs (nicotine, alcohol, marijuana, opiates, SSRIs) but without cocaine. Infants with PCE exhibited lesser total gray matter (GM) volume and greater total cerebral spinal fluid (CSF) volume compared with controls and infants with non-cocaine drug exposure. Analysis of regional volumes revealed that whole brain GM differences were driven primarily by lesser GM in prefrontal and frontal brain regions in infants with PCE, while more posterior regions (parietal, occipital) did not differ across groups. Greater CSF volumes in PCE infants were present in prefrontal, frontal and parietal but not occipital regions. Greatest differences (GM reduction, CSF enlargement) in PCE infants were observed in dorsal prefrontal cortex. Results suggest that PCE is associated with structural deficits in neonatal cortical gray matter, specifically in prefrontal and frontal regions involved in executive function and inhibitory control. Longitudinal study is required to determine whether these early differences persist and contribute to deficits in cognitive functions and enhanced risk for drug abuse seen at school age and in later life. PMID:24999039

  16. Brain structural and functional correlates of resilience to Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Sophia eFrangou

    2012-01-01

    Full Text Available Background: Resilient adaptation can be construed in different ways, but as used here it refers to the adaptive brain changes associated with avoidance of psychopathology despite familiar risk for Bipolar Disorder (BD. Although family history of BD is associated with elevated risk of affective morbidity a significant proportion of first-degree relatives of BD patients remains free of psychopathology. Examination of brain structure and function in these individuals may inform on adaptive changes that may pre-empt disease expression. Methods: Data presented here are derived from the Vulnerability to Bipolar Disorders (VIBES study which includes patients with BD, asymptomatic relatives and healthy controls. Participants underwent extensive investigations including brain structural (sMRI and functional magnetic resonance imaging (fMRI. The data presented here focus on sMRI voxel-based-morphometry and on conventional and connectivity analyses of fMRI data obtained during the Stroop Colour Word Test (SCWT, a task of cognitive control during conflict resolution. All analyses were implemented in SPM (www.fil.ion.ucl.ac.uk/spm. Resilience in relatives was operationalized as the absence of clinical-range symptoms.Results: Resilient relatives of BD patients expressed structural, functional and connectivity changes reflecting the effect of genetic risk on the brain. These included increased insular volume, decreased activation within the posterior and inferior parietal regions involved in selective attention during the SCWT, and reduced fronto-insular and fronto-cingulate connectivity.Resilience was associated with increased cerebellar vermal volume and enhanced functional coupling between the dorsal and the ventral prefrontal cortex. Conclusions: Our findings suggests the presence of biological mechanisms associated with resilient adaptation of brain networks and pave the way for the identification of outcome-specific trajectories given a particular

  17. Surface displacement based shape analysis of central brain structures in preterm-born children

    Science.gov (United States)

    Garg, Amanmeet; Grunau, Ruth E.; Popuri, Karteek; Miller, Steven; Bjornson, Bruce; Poskitt, Kenneth J.; Beg, Mirza Faisal

    2016-03-01

    Many studies using T1 magnetic resonance imaging (MRI) data have found associations between changes in global metrics (e.g. volume) of brain structures and preterm birth. In this work, we use the surface displacement feature extracted from the deformations of the surface models of the third ventricle, fourth ventricle and brainstem to capture the variation in shape in these structures at 8 years of age that may be due to differences in the trajectory of brain development as a result of very preterm birth (24-32 weeks gestation). Understanding the spatial patterns of shape alterations in these structures in children who were born very preterm as compared to those who were born at full term may lead to better insights into mechanisms of differing brain development between these two groups. The T1 MRI data for the brain was acquired from children born full term (FT, n=14, 8 males) and preterm (PT, n=51, 22 males) at age 8-years. Accurate segmentation labels for these structures were obtained via a multi-template fusion based segmentation method. A high dimensional non-rigid registration algorithm was utilized to register the target segmentation labels to a set of segmentation labels defined on an average-template. The surface displacement data for the brainstem and the third ventricle were found to be significantly different (p preterm birth.

  18. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E.; Kim, Hee Jin; Na, Duk L.; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are “small world.” There were significant difference between NC and AD group in characteristic path lengths (z = −2.97, p brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC dataset. PMID:27635121

  19. Prevention and treatment of traumatic brain injury due to rapid-onset natural disasters

    Directory of Open Access Journals (Sweden)

    James L. Regens

    2014-04-01

    Full Text Available The prevention and treatment of traumatic brain injury (TBI attributable to rapid-onset natural disasters is a major challenge confronting disaster preparedness planners and emergency medical personnel responding to those incidents. The kinetic energy released by rapid-onset natural disasters such as earthquakes, hurricanes or typhoons, and tornadoes can cause mild, moderate or severe TBIs. As a result, neurotrauma is a major risk factor for mortality and morbidity outcomes within the spatial domain impacted by a rapid-onset natural disaster. This review article elucidates major challenges associated with immediate emergency medical response, long-term care, and prevention of post-event increases in pediatric TBIs because of child abuse when rapid-onset natural disasters occur.

  20. Manic Symptoms Due to Methylphenidate Use in an Adolescent with Traumatic Brain Injury

    Science.gov (United States)

    Ekinci, Ozalp; Direk, Meltem Çobanoğullari; Ekinci, Nuran; Okuyaz, Cetin

    2016-01-01

    Almost one-fifth of children who sustain a traumatic brain injury (TBI) are under the risk of attention problems after injury. The efficacy and tolerability of methylphenidate (MPH) in children with a history of TBI have not been completely identified. In this case report, MPH-induced manic symptoms in an adolescent with TBI will be summarized. A male patient aged 17 years was admitted with the complaints of attention difficulties on schoolwork and forgetfullness which became evident after TBI. Long-acting MPH was administered with the dose of 18 mg/day for attention problems. After one week, patient presented with the complaints of talking to himself, delusional thoughts, irritability and sleeplessness. This case highlights the fact that therapeutic dose of MPH may cause mania-like symptoms in children with TBI. Close monitarization and slow dose titration are crucial when considering MPH in children with TBI. PMID:27489389

  1. Manic Symptoms Due to Methylphenidate Use in an Adolescent with Traumatic Brain Injury.

    Science.gov (United States)

    Ekinci, Ozalp; Direk, Meltem Çobanoğullari; Ekinci, Nuran; Okuyaz, Cetin

    2016-08-31

    Almost one-fifth of children who sustain a traumatic brain injury (TBI) are under the risk of attention problems after injury. The efficacy and tolerability of methylphenidate (MPH) in children with a history of TBI have not been completely identified. In this case report, MPH-induced manic symptoms in an adolescent with TBI will be summarized. A male patient aged 17 years was admitted with the complaints of attention difficulties on schoolwork and forgetfullness which became evident after TBI. Long-acting MPH was administered with the dose of 18 mg/day for attention problems. After one week, patient presented with the complaints of talking to himself, delusional thoughts, irritability and sleeplessness. This case highlights the fact that therapeutic dose of MPH may cause mania-like symptoms in children with TBI. Close monitarization and slow dose titration are crucial when considering MPH in children with TBI. PMID:27489389

  2. Quantum Interference in Cognition: Structural Aspects of the Brain

    CERN Document Server

    Aerts, Diederik

    2012-01-01

    We identify the presence of typically quantum effects, namely 'superposition' and 'interference', in what happens when human concepts are combined, and provide a quantum model in complex Hilbert space that represents faithfully experimental data measuring the situation of combining concepts. Our model shows how 'interference of concepts' explains the effects of underextension and overextension when two concepts combine to the disjunction of these two concepts. This result supports our earlier hypothesis that human thought has a superposed two-layered structure, one layer consisting of 'classical logical thought' and a superposed layer consisting of 'quantum conceptual thought'. Possible connections with recent findings of a 'grid-structure' for the brain are analyzed, and influences on the mind/brain relation, and consequences on applied disciplines, such as artificial intelligence and quantum computation, are considered.

  3. Brain structure abnormalities in adolescent girls with conduct disorder

    OpenAIRE

    Fairchild, Graeme; Hagan, Cindy C.; Nicholas D Walsh; Passamonti, Luca; Calder, Andrew J.; Goodyer, Ian M.

    2012-01-01

    Background Conduct disorder (CD) in female adolescents is associated with a range of negative outcomes, including teenage pregnancy and antisocial personality disorder. Although recent studies have documented changes in brain structure and function in male adolescents with CD, there have been no neuroimaging studies of female adolescents with CD. Our primary objective was to investigate whether female adolescents with CD show changes in grey matter volume. Our secondary aim was to assess for ...

  4. Brain structural correlates of complex sentence comprehension in children

    Directory of Open Access Journals (Sweden)

    Anja Fengler

    2015-10-01

    Full Text Available Prior structural imaging studies found initial evidence for the link between structural gray matter changes and the development of language performance in children. However, previous studies generally only focused on sentence comprehension. Therefore, little is known about the relationship between structural properties of brain regions relevant to sentence processing and more specific cognitive abilities underlying complex sentence comprehension. In this study, whole-brain magnetic resonance images from 59 children between 5 and 8 years were assessed. Scores on a standardized sentence comprehension test determined grammatical proficiency of our participants. A confirmatory factory analysis corroborated a grammar-relevant and a verbal working memory-relevant factor underlying the measured performance. Voxel-based morphometry of gray matter revealed that while children's ability to assign thematic roles is positively correlated with gray matter probability (GMP in the left inferior temporal gyrus and the left inferior frontal gyrus, verbal working memory-related performance is positively correlated with GMP in the left parietal operculum extending into the posterior superior temporal gyrus. Since these areas are known to be differentially engaged in adults’ complex sentence processing, our data suggest a specific correspondence between children's GMP in language-relevant brain regions and differential cognitive abilities that guide their sentence comprehension.

  5. Structural similarity analysis for brain MR image quality assessment

    Science.gov (United States)

    Punga, Mirela Visan; Moldovanu, Simona; Moraru, Luminita

    2014-11-01

    Brain MR images are affected and distorted by various artifacts as noise, blur, blotching, down sampling or compression and as well by inhomogeneity. Usually, the performance of pre-processing operation is quantified by using the quality metrics as mean squared error and its related metrics such as peak signal to noise ratio, root mean squared error and signal to noise ratio. The main drawback of these metrics is that they fail to take the structural fidelity of the image into account. For this reason, we addressed to investigate the structural changes related to the luminance and contrast variation (as non-structural distortions) and to denoising process (as structural distortion)through an alternative metric based on structural changes in order to obtain the best image quality.

  6. Death Associated Protein Kinases: Molecular Structure and Brain Injury

    Directory of Open Access Journals (Sweden)

    Claire Thornton

    2013-07-01

    Full Text Available Perinatal brain damage underlies an important share of motor and neurodevelopmental disabilities, such as cerebral palsy, cognitive impairment, visual dysfunction and epilepsy. Clinical, epidemiological, and experimental studies have revealed that factors such as inflammation, excitotoxicity and oxidative stress contribute considerably to both white and grey matter injury in the immature brain. A member of the death associated protein kinase (DAPk family, DAPk1, has been implicated in cerebral ischemic damage, whereby DAPk1 potentiates NMDA receptor-mediated excitotoxicity through interaction with the NR2BR subunit. DAPk1 also mediate a range of activities from autophagy, membrane blebbing and DNA fragmentation ultimately leading to cell death. DAPk mRNA levels are particularly highly expressed in the developing brain and thus, we hypothesize that DAPk1 may play a role in perinatal brain injury. In addition to reviewing current knowledge, we present new aspects of the molecular structure of DAPk domains, and relate these findings to interacting partners of DAPk1, DAPk-regulation in NMDA-induced cerebral injury and novel approaches to blocking the injurious effects of DAPk1.

  7. Structural brain correlates associated with professional handball playing.

    Directory of Open Access Journals (Sweden)

    Jürgen Hänggi

    Full Text Available There is no doubt that good bimanual performance is very important for skilled handball playing. The control of the non-dominant hand is especially demanding since efficient catching and throwing needs both hands.We investigated training-induced structural neuroplasticity in professional handball players using several structural neuroimaging techniques and analytic approaches and also provide a review of the literature about sport-induced structural neuroplastic alterations. Structural brain adaptations were expected in regions relevant for motor and somatosensory processing such as the grey matter (GM of the primary/secondary motor (MI/supplementary motor area, SMA and somatosensory cortex (SI/SII, basal ganglia, thalamus, and cerebellum and in the white matter (WM of the corticospinal tract (CST and corpus callosum, stronger in brain regions controlling the non-dominant left hand.Increased GM volume in handball players compared with control subjects were found in the right MI/SI, bilateral SMA/cingulate motor area, and left intraparietal sulcus. Fractional anisotropy (FA and axial diffusivity were increased within the right CST in handball players compared with control women. Age of handball training commencement correlated inversely with GM volume in the right and left MI/SI and years of handball training experience correlated inversely with radial diffusivity in the right CST. Subcortical structures tended to be larger in handball players. The anatomical measures of the brain regions associated with handball playing were positively correlated in handball players, but not interrelated in control women.Training-induced structural alterations were found in the somatosensory-motor network of handball players, more pronounced in the right hemisphere controlling the non-dominant left hand. Correlations between handball training-related measures and anatomical differences suggest neuroplastic adaptations rather than a genetic predisposition for a

  8. [A peculiar speech disorder due to bomb injury of the brain].

    Science.gov (United States)

    Hem, Erlend

    2006-12-14

    Oslo was bombed by British bombers 6 September 1941, and a 28-year-old woman was hit on the head by a bomb fragment. She was seriously wounded with a large defect in the cranium frontally on the left side, and it was believed that she was not going to survive. She was unconscious for 3-4 days, and when she woke up she had right-sided hemiplegia and complete aphasia. She gradually recovered, and two months later she was discharged from hospital. Remarkably, the brain damage had altered her melody of language, and she spoke with a German-like accent. This led to problems for her during the war: she was for example not served in shops. The case story was published after the war by the Norwegian neurologist Georg Herman Monrad-Krohn (1884-1964), and it is the best known case of the so-called foreign accent syndrome. In this paper, this rare syndrome is presented, emphasising Monrad-Krohn's patient and based on his writings and the patient's medical record.

  9. OPTIMAL REPRESENTATION OF MER SIGNALS APPLIED TO THE IDENTIFICATION OF BRAIN STRUCTURES DURING DEEP BRAIN STIMULATION

    Directory of Open Access Journals (Sweden)

    Hernán Darío Vargas Cardona

    2015-07-01

    Full Text Available Identification of brain signals from microelectrode recordings (MER is a key procedure during deep brain stimulation (DBS applied in Parkinson’s disease patients. The main purpose of this research work is to identify with high accuracy a brain structure called subthalamic nucleus (STN, since it is the target structure where the DBS achieves the best therapeutic results. To do this, we present an approach for optimal representation of MER signals through method of frames. We obtain coefficients that minimize the Euclidean norm of order two. From optimal coefficients, we extract some features from signals combining the wavelet packet and cosine dictionaries. For a comparison frame with the state of the art, we also process the signals using the discrete wavelet transform (DWT with several mother functions. We validate the proposed methodology in a real data base. We employ simple supervised machine learning algorithms, as the K-Nearest Neighbors classifier (K-NN, a linear Bayesian classifier (LDC and a quadratic Bayesian classifier (QDC. Classification results obtained with the proposed method improves significantly the performance of the DWT. We achieve a positive identification of the STN superior to 97,6%. Identification outcomes achieved by the MOF are highly accurate, as we can potentially get a false positive rate of less than 2% during the DBS.

  10. Brain

    Science.gov (United States)

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  11. Complex regional pain syndrome type I affects brain structure in prefrontal and motor cortex.

    Directory of Open Access Journals (Sweden)

    Burkhard Pleger

    Full Text Available The complex regional pain syndrome (CRPS is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated. We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1 and motor cortex (M1 contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the "non-flipped" data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the "flipped" data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control.

  12. Complex regional pain syndrome type I affects brain structure in prefrontal and motor cortex.

    Science.gov (United States)

    Pleger, Burkhard; Draganski, Bogdan; Schwenkreis, Peter; Lenz, Melanie; Nicolas, Volkmar; Maier, Christoph; Tegenthoff, Martin

    2014-01-01

    The complex regional pain syndrome (CRPS) is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated. We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1) and motor cortex (M1) contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls) were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the "non-flipped" data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the "flipped" data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control.

  13. Locomotion without a brain: physical reservoir computing in tensegrity structures.

    Science.gov (United States)

    Caluwaerts, K; D'Haene, M; Verstraeten, D; Schrauwen, B

    2013-01-01

    Embodiment has led to a revolution in robotics by not thinking of the robot body and its controller as two separate units, but taking into account the interaction of the body with its environment. By investigating the effect of the body on the overall control computation, it has been suggested that the body is effectively performing computations, leading to the term morphological computation. Recent work has linked this to the field of reservoir computing, allowing one to endow morphologies with a theory of universal computation. In this work, we study a family of highly dynamic body structures, called tensegrity structures, controlled by one of the simplest kinds of "brains." These structures can be used to model biomechanical systems at different scales. By analyzing this extreme instantiation of compliant structures, we demonstrate the existence of a spectrum of choices of how to implement control in the body-brain composite. We show that tensegrity structures can maintain complex gaits with linear feedback control and that external feedback can intrinsically be integrated in the control loop. The various linear learning rules we consider differ in biological plausibility, and no specific assumptions are made on how to implement the feedback in a physical system.

  14. Locomotion without a brain: physical reservoir computing in tensegrity structures.

    Science.gov (United States)

    Caluwaerts, K; D'Haene, M; Verstraeten, D; Schrauwen, B

    2013-01-01

    Embodiment has led to a revolution in robotics by not thinking of the robot body and its controller as two separate units, but taking into account the interaction of the body with its environment. By investigating the effect of the body on the overall control computation, it has been suggested that the body is effectively performing computations, leading to the term morphological computation. Recent work has linked this to the field of reservoir computing, allowing one to endow morphologies with a theory of universal computation. In this work, we study a family of highly dynamic body structures, called tensegrity structures, controlled by one of the simplest kinds of "brains." These structures can be used to model biomechanical systems at different scales. By analyzing this extreme instantiation of compliant structures, we demonstrate the existence of a spectrum of choices of how to implement control in the body-brain composite. We show that tensegrity structures can maintain complex gaits with linear feedback control and that external feedback can intrinsically be integrated in the control loop. The various linear learning rules we consider differ in biological plausibility, and no specific assumptions are made on how to implement the feedback in a physical system. PMID:23186351

  15. Uncovering latent deficits due to mild traumatic brain injury by using normobaric hypoxia stress.

    Science.gov (United States)

    Temme, Leonard; Bleiberg, Joseph; Reeves, Dennis; Still, David L; Levinson, Dan; Browning, Rebecca

    2013-01-01

    Memory deficits and other cognitive symptoms frequently associated with mTBI are commonly thought to resolve within 7-10 days. This generalization is based principally on observations made in individuals who are in the unstressed environmental conditions typical of a clinic and so does not consider the impact of physiologic, environmental, or psychological stress. Normobaric hypoxic stress can be generated with normal mean sea level (MSL) air, which is about 21% oxygen (O2) and 78% nitrogen (N), by reducing the percentage of O2 and increasing the percentage of N so that the resultant mixed-gas has a partial pressure of O2 approximating that of specified altitudes. This technique was used to generate normobaric hypoxic equivalents of 8,000, 12,000, and 14,000 feet above MSL in a group of 36 volunteers with a mTBI history and an equal number of controls matched on the basis of age, gender, tobacco smoking consumption, weight, height, and body mass index. Short-term visual memory was tested using the Matching to Sample (M2S) subtest of the BrainCheckers analog of the Automated Neuropsychological Assessment Metrics. Although there were no significant differences in M2S performance between the two groups of subjects at MSL, with increased altitude, the mTBI group performance was significantly worse than that of the control group. When the subjects were returned to MSL, the difference disappeared. This finding suggests that the "hypoxic challenge" paradigm developed here has potential clinical utility for assessing the effects of mTBI in individuals who appear asymptomatic under normal conditions. PMID:23641232

  16. Brain structure and dynamics across scales: in search of rules.

    Science.gov (United States)

    Wang, Xiao-Jing; Kennedy, Henry

    2016-04-01

    Louis Henry Sullivan, the father of skyscrapers, famously stated 'Form ever follows function'. In this short review, we will focus on the relationship between form (structure) and function (dynamics) in the brain. We summarize recent advances on the quantification of directed- and weighted-mesoscopic connectivity of mammalian cortex, the exponential distance rule for mesoscopic and microscopic circuit wiring, a spatially embedded random model of inter-areal cortical networks, and a large-scale dynamical circuit model of money's cortex that gives rise to a hierarchy of timescales. These findings demonstrate that inter-areal cortical networks are dense (hence such concepts as 'small-world' need to be refined when applied to the brain), spatially dependent (therefore purely topological approach of graph theory has limited applicability) and heterogeneous (consequently cortical areas cannot be treated as identical 'nodes'). PMID:26868043

  17. Memory deficits due to brain injury: unique PET findings and dream alterations.

    Science.gov (United States)

    Nishida, Masaki; Nariai, Tadashi; Hiura, Mikio; Ishii, Kenji; Nishikawa, Toru

    2011-01-01

    The authors herein report the case of a young male with memory deficits due to a traumatic head injury, who presented with sleep-related symptoms such as hypersomnia and dream alterations. Although MRI and polysomnography showed no abnormalities, (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) and (11)C flumazenil (FMZ)-PET revealed findings consistent with cerebral damage to the affected temporal region. The memory deficit of the patient gradually improved in parallel with the relief of the sleep-related symptoms. FDG-PET showed considerable improvement in glucose metabolism when he had recovered, however, evidence of neural loss remained in the FMZ-PET findings. PMID:22674950

  18. Life-threatening Anemia with Hemolysis, Thrombocytopenia and Brain Atrophy due to Vitamin B12 Deficiency

    Directory of Open Access Journals (Sweden)

    Ebru Yilmaz Keskin

    2014-08-01

    Full Text Available Megaloblastic anemia due to vitamin B12 deficiency is rare in infancy. It usually occurs in exclusively breast-fed infants born to vitamin B12-deficient mothers. We report a one-year-old female infant with initial diagnosis of leukemia who was found severely vitamin B12-deficient secondary to maternal deficiency. She had marked neurodevelopmental retardation, and presented with life-threatening anemia, findings of hemolysis, thrombocytopenia and cerebral atrophy on magnetic resonance imaging. [Cukurova Med J 2014; 39(4.000: 900-904

  19. Investigating structural brain changes of dehydration using voxel-based morphometry.

    Directory of Open Access Journals (Sweden)

    Daniel-Paolo Streitbürger

    Full Text Available Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM, white matter (WM, and cerebrospinal fluid (CSF. The datasets were analyzed using voxel-based morphometry (VBM, a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheimer's disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects' hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain.

  20. Investigating structural brain changes of dehydration using voxel-based morphometry.

    Science.gov (United States)

    Streitbürger, Daniel-Paolo; Möller, Harald E; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Schroeter, Matthias L; Mueller, Karsten

    2012-01-01

    Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1)-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (VBM), a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheimer's disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects' hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain. PMID:22952926

  1. Variation in hominid brain size: how much is due to method?

    Science.gov (United States)

    De Miguel, C; Henneberg, M

    2001-01-01

    Brain size represented by cranial capacity (CC) is one of the most frequently analysed characters of hominids. Accuracy of individual CC estimates depends on completeness of specimens and methods used for reconstruction and measurement. A file of published estimates of CC of hominids dated from 3.2 Ma (million years) to 10 Ka (thousand years) including 606 estimates for 243 specimens was compiled. In the file, 75 specimens are available with multiple values (3 to 15) obtained by various methods and/or by various authors. Using individuals as classes in ANOVA, intraclass variation, which represents "error" of estimates, was calculated. For the total sample of multiple estimates (N = 382) the error variance is 5315 ml2. The error standard deviation is 73 ml (coefficient of variation (CV = 7.3%), quite large in comparison to the actual variation in CC in modern humans, SD = 157 ml (CV = 11.6%). This large error makes us wonder whether any fossil can be reliably placed with respect to a particular "cerebral Rubicon" between palaeospecies. Recent discussions concerning cranial capacity of Stw505 are a case in point regarding errors in CC estimation. In actual repeated 30 time measurements on a research quality cast we obtained with various methods (water, seeds, plasticine) CC estimates ranging from 484 to 586 ml. The range of estimates in the literature is from 515 to 625 ml. When hominid CC by taxon with date as a covariate is subjected to ANOVA, taxon is responsible for 5% of the variance while date is responsible for the main portion, (89%). The relationship between CC and date is best characterised as a gradual time trend. It is proven by the ANOVA test for linearity, by gamma test for trend and by ASReml fitting of a linear function. The line of best fit to this time trend is a double exponential curve which explains 90% of the total variance in CC: CC = 306.63 (4.83(0.9995)DATE) Essentially the same curve fits subsamples of CC dated at less than 1 Ma and at 3

  2. Asymmetric bias in user guided segmentations of brain structures.

    Science.gov (United States)

    Maltbie, Eric; Bhatt, Kshamta; Paniagua, Beatriz; Smith, Rachel G; Graves, Michael M; Mosconi, Matthew W; Peterson, Sarah; White, Scott; Blocher, Joseph; El-Sayed, Mohammed; Hazlett, Heather C; Styner, Martin A

    2012-01-16

    Brain morphometric studies often incorporate comparative hemispheric asymmetry analyses of segmented brain structures. In this work, we present evidence that common user guided structural segmentation techniques exhibit strong left-right asymmetric biases and thus fundamentally influence any left-right asymmetry analyses. In this study, MRI scans from ten pediatric subjects were employed for studying segmentations of amygdala, globus pallidus, putamen, caudate, and lateral ventricle. Additionally, two pediatric and three adult scans were used for studying hippocampus segmentation. Segmentations of the sub-cortical structures were performed by skilled raters using standard manual and semi-automated methods. The left-right mirrored versions of each image were included in the data and segmented in a random order to assess potential left-right asymmetric bias. Using shape analysis we further assessed whether the asymmetric bias is consistent across subjects and raters with the focus on the hippocampus. The user guided segmentation techniques on the sub-cortical structures exhibited left-right asymmetric volume bias with the hippocampus displaying the most significant asymmetry values (porigin of this asymmetric bias is considered to be based in laterality of visual perception; therefore segmentations with any degree of user interaction contain an asymmetric bias. The aim of our study is to raise awareness in the neuroimaging community regarding the presence of the asymmetric bias and its influence on any left-right hemispheric analyses. We also recommend reexamining previous research results in the light of this new finding. PMID:21889995

  3. A technique for the deidentification of structural brain MR images

    DEFF Research Database (Denmark)

    Bischoff-Grethe, Amanda; Ozyurt, I Burak; Busa, Evelina;

    2007-01-01

    Due to the increasing need for subject privacy, the ability to deidentify structural MR images so that they do not provide full facial detail is desirable. A program was developed that uses models of nonbrain structures for removing potentially identifying facial features. When a novel image is p...

  4. Frontal white matter volume is associated with brain enlargement and higher structural connectivity in anthropoid primates.

    Directory of Open Access Journals (Sweden)

    Jeroen Bert Smaers

    Full Text Available Previous research has indicated the importance of the frontal lobe and its 'executive' connections to other brain structures as crucial in explaining primate neocortical adaptations. However, a representative sample of volumetric measurements of frontal connective tissue (white matter has not been available. In this study, we present new volumetric measurements of white and grey matter in the frontal and non-frontal neocortical lobes from 18 anthropoid species. We analyze this data in the context of existing theories of neocortex, frontal lobe and white versus grey matter hyperscaling. Results indicate that the 'universal scaling law' of neocortical white to grey matter applies separately for frontal and non-frontal lobes; that hyperscaling of both neocortex and frontal lobe to rest of brain is mainly due to frontal white matter; and that changes in frontal (but not non-frontal white matter volume are associated with changes in rest of brain and basal ganglia, a group of subcortical nuclei functionally linked to 'executive control'. Results suggest a central role for frontal white matter in explaining neocortex and frontal lobe hyperscaling, brain size variation and higher neural structural connectivity in anthropoids.

  5. Structural brain network: What is the effect of LiFE optimization of whole brain tractography?

    Directory of Open Access Journals (Sweden)

    Shouliang eQi

    2016-02-01

    Full Text Available Structural brain networks constructed based on diffusion-weighted MRI (dMRI have provided a systems perspective to explore the organization of the human brain. Some redundant and nonexistent fibers, however, are inevitably generated in whole brain tractography. We propose to add one critical step while constructing the networks to remove these fibers using the linear fascicle evaluation (LiFE method, and study the differences between the networks with and without LiFE optimization. For a cohort of 9 healthy adults and for 9 out of the 35 subjects from Human Connectome Project, the T1-weighted images and dMRI data are analyzed. Each brain is parcellated into 90 regions-of-interest, whilst a probabilistic tractography algorithm is applied to generate the original connectome. The elimination of redundant and nonexistent fibers from the original connectome by LiFE creates the optimized connectome, and the random selection of the same number of fibers as the optimized connectome creates the non-optimized connectome. The combination of parcellations and these connectomes leads to the optimized and non-optimized networks, respectively. The optimized networks are constructed with six weighting schemes, and the correlations of different weighting methods are analyzed. The fiber length distributions of the non-optimized and optimized connectomes are compared. The optimized and non-optimized networks are compared with regard to edges, nodes and networks, within a sparsity range of 0.75-0.95. It has been found that relatively more short fibers exist in the optimized connectome. About 24.0% edges of the optimized network are significantly different from those in the non-optimized network at a sparsity of 0.75. About 13.2% of edges are classified as false positives or the possible missing edges. The strength and betweenness centrality of some nodes are significantly different for the non-optimized and optimized networks, but not the node efficiency. The

  6. Brain SCALE : Brain Structure and Cognition: an Adolescent Longitudinal Twin Study into the Genetic Etiology of Individual Differences

    NARCIS (Netherlands)

    van Soelen, Inge L. C.; Brouwer, Rachel M.; Peper, Jiska S.; van Leeuwen, Marieke; Koenis, Marinka M. G.; van Beijsterveldt, Toos C. E. M.; Swagerman, Suzanne C.; Kahn, Rene S.; Pol, Hilleke E. Hulshoff; Boomsma, Dorret I.

    2012-01-01

    From childhood into adolescence, the child's brain undergoes considerable changes in both structure and function. Twin studies are of great value to explore to what extent genetic and environmental factors explain individual differences in brain development and cognition. In The Netherlands, we init

  7. Brain Structure and Executive Functions in Children with Cerebral Palsy: A Systematic Review

    Science.gov (United States)

    Weierink, Lonneke; Vermeulen, R. Jeroen; Boyd, Roslyn N.

    2013-01-01

    This systematic review aimed to establish the current knowledge about brain structure and executive function (EF) in children with cerebral palsy (CP). Five databases were searched (up till July 2012). Six articles met the inclusion criteria, all included structural brain imaging though no functional brain imaging. Study quality was assessed using…

  8. Abdominal Pain, the Adolescent and Altered Brain Structure and Function.

    Directory of Open Access Journals (Sweden)

    Catherine S Hubbard

    Full Text Available Irritable bowel syndrome (IBS is a functional gastrointestinal (GI disorder of unknown etiology. Although relatively common in children, how this condition affects brain structure and function in a pediatric population remains unclear. Here, we investigate brain changes in adolescents with IBS and healthy controls. Imaging was performed with a Siemens 3 Tesla Trio Tim MRI scanner equipped with a 32-channel head coil. A high-resolution T1-weighted anatomical scan was acquired followed by a T2-weighted functional scan. We used a surface-based morphometric approach along with a seed-based resting-state functional connectivity (RS-FC analysis to determine if groups differed in cortical thickness and whether areas showing structural differences also showed abnormal RS-FC patterns. Patients completed the Abdominal Pain Index and the GI Module of the Pediatric Quality of Life Inventory to assess abdominal pain severity and impact of GI symptoms on health-related quality of life (HRQOL. Disease duration and pain intensity were also assessed. Pediatric IBS patients, relative to controls, showed cortical thickening in the posterior cingulate (PCC, whereas cortical thinning in posterior parietal and prefrontal areas were found, including the dorsolateral prefrontal cortex (DLPFC. In patients, abdominal pain severity was related to cortical thickening in the intra-abdominal area of the primary somatosensory cortex (SI, whereas HRQOL was associated with insular cortical thinning. Disease severity measures correlated with cortical thickness in bilateral DLPFC and orbitofrontal cortex. Patients also showed reduced anti-correlations between PCC and DLPFC compared to controls, a finding that may reflect aberrant connectivity between default mode and cognitive control networks. We are the first to demonstrate concomitant structural and functional brain changes associated with abdominal pain severity, HRQOL related to GI-specific symptoms, and disease

  9. Abdominal Pain, the Adolescent and Altered Brain Structure and Function.

    Science.gov (United States)

    Hubbard, Catherine S; Becerra, Lino; Heinz, Nicole; Ludwick, Allison; Rasooly, Tali; Wu, Rina; Johnson, Adriana; Schechter, Neil L; Borsook, David; Nurko, Samuel

    2016-01-01

    Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder of unknown etiology. Although relatively common in children, how this condition affects brain structure and function in a pediatric population remains unclear. Here, we investigate brain changes in adolescents with IBS and healthy controls. Imaging was performed with a Siemens 3 Tesla Trio Tim MRI scanner equipped with a 32-channel head coil. A high-resolution T1-weighted anatomical scan was acquired followed by a T2-weighted functional scan. We used a surface-based morphometric approach along with a seed-based resting-state functional connectivity (RS-FC) analysis to determine if groups differed in cortical thickness and whether areas showing structural differences also showed abnormal RS-FC patterns. Patients completed the Abdominal Pain Index and the GI Module of the Pediatric Quality of Life Inventory to assess abdominal pain severity and impact of GI symptoms on health-related quality of life (HRQOL). Disease duration and pain intensity were also assessed. Pediatric IBS patients, relative to controls, showed cortical thickening in the posterior cingulate (PCC), whereas cortical thinning in posterior parietal and prefrontal areas were found, including the dorsolateral prefrontal cortex (DLPFC). In patients, abdominal pain severity was related to cortical thickening in the intra-abdominal area of the primary somatosensory cortex (SI), whereas HRQOL was associated with insular cortical thinning. Disease severity measures correlated with cortical thickness in bilateral DLPFC and orbitofrontal cortex. Patients also showed reduced anti-correlations between PCC and DLPFC compared to controls, a finding that may reflect aberrant connectivity between default mode and cognitive control networks. We are the first to demonstrate concomitant structural and functional brain changes associated with abdominal pain severity, HRQOL related to GI-specific symptoms, and disease-specific measures in

  10. Chronic Methamphetamine Effects on Brain Structure and Function in Rats

    Science.gov (United States)

    Thanos, Panayotis K.; Kim, Ronald; Delis, Foteini; Ananth, Mala; Chachati, George; Rocco, Mark J.; Masad, Ihssan; Muniz, Jose A.; Grant, Samuel C.; Gold, Mark S.; Cadet, Jean Lud; Volkow, Nora D.

    2016-01-01

    Methamphetamine (MA) addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI) studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET) studies have shown decreased brain glucose metabolism (BGluM) in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls), or low dose (LD) MA (4 mg/kg), or high dose (HD) MA (8 mg/kg). Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG), and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  11. Chronic Methamphetamine Effects on Brain Structure and Function in Rats.

    Directory of Open Access Journals (Sweden)

    Panayotis K Thanos

    Full Text Available Methamphetamine (MA addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET studies have shown decreased brain glucose metabolism (BGluM in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls, or low dose (LD MA (4 mg/kg, or high dose (HD MA (8 mg/kg. Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG, and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  12. Association between brain structure and phenotypic characteristics in pedophilia.

    Science.gov (United States)

    Poeppl, Timm B; Nitschke, Joachim; Santtila, Pekka; Schecklmann, Martin; Langguth, Berthold; Greenlee, Mark W; Osterheider, Michael; Mokros, Andreas

    2013-05-01

    Studies applying structural neuroimaging to pedophiles are scarce and have shown conflicting results. Although first findings suggested reduced volume of the amygdala, pronounced gray matter decreases in frontal regions were observed in another group of pedophilic offenders. When compared to non-sexual offenders instead of community controls, pedophiles revealed deficiencies in white matter only. The present study sought to test the hypotheses of structurally compromised prefrontal and limbic networks and whether structural brain abnormalities are related to phenotypic characteristics in pedophiles. We compared gray matter volume of male pedophilic offenders and non-sexual offenders from high-security forensic hospitals using voxel-based morphometry in cross-sectional and correlational whole-brain analyses. The significance threshold was set to p pedophiles exhibited a volume reduction of the right amygdala (small volume corrected). Within the pedophilic group, pedosexual interest and sexual recidivism were correlated with gray matter decrease in the left dorsolateral prefrontal cortex (r = -.64) and insular cortex (r = -.45). Lower age of victims was strongly associated with gray matter reductions in the orbitofrontal cortex (r = .98) and angular gyri bilaterally (r = .70 and r = .93). Our findings of specifically impaired neural networks being related to certain phenotypic characteristics might account for the heterogeneous results in previous neuroimaging studies of pedophilia. The neuroanatomical abnormalities in pedophilia seem to be of a dimensional rather than a categorical nature, supporting the notion of a multifaceted disorder. PMID:23399486

  13. Distinct Genetic Influences on Cortical and Subcortical Brain Structures

    Science.gov (United States)

    Wen, Wei; Thalamuthu, Anbupalam; Mather, Karen A.; Zhu, Wanlin; Jiang, Jiyang; de Micheaux, Pierre Lafaye; Wright, Margaret J.; Ames, David; Sachdev, Perminder S.

    2016-09-01

    This study examined the heritability of brain grey matter structures in a subsample of older adult twins (93 MZ and 68 DZ twin pairs; mean age 70 years) from the Older Australian Twins Study. The heritability estimates of subcortical regions ranged from 0.41 (amygdala) to 0.73 (hippocampus), and of cortical regions, from 0.55 (parietal lobe) to 0.78 (frontal lobe). Corresponding structures in the two hemispheres were influenced by the same genetic factors and high genetic correlations were observed between the two hemispheric regions. There were three genetically correlated clusters, comprising (i) the cortical lobes (frontal, temporal, parietal and occipital lobes); (ii) the basal ganglia (caudate, putamen and pallidum) with weak genetic correlations with cortical lobes, and (iii) the amygdala, hippocampus, thalamus and nucleus accumbens grouped together, which genetically correlated with both basal ganglia and cortical lobes, albeit relatively weakly. Our study demonstrates a complex but patterned and clustered genetic architecture of the human brain, with divergent genetic determinants of cortical and subcortical structures, in particular the basal ganglia.

  14. Treatment resistant schizophrenia: Course of brain structure and function.

    Science.gov (United States)

    Harvey, Philip D; Rosenthal, Jennifer B

    2016-10-01

    Approximately 30% of people with schizophrenia manifest a minimal response to conventional and atypical antipsychotic medications and manifest continuous symptoms of psychosis, with this condition referred to as "treatment resistant schizophrenia (TRS)". There are several neurobiological consequences of continuous psychosis, including regional cortical atrophy and ventricular enlargement. Pharmacological treatments are available for TRS, with at least 1/3 of patients responding to treatment with clozapine. In this paper we review the evidence regarding the course of treatment resistant schizophrenia, as well as changes in brain structure and function in psychosis and on the possible role of clozapine treatment in altering cortical deterioration in patients with TRS. PMID:26925705

  15. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients.

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E; Kim, Hee Jin; Na, Duk L; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are "small world." There were significant difference between NC and AD group in characteristic path lengths (z = -2.97, p < 0.01) and small-worldness values (z = 4.05, p < 0.01). Clustering coefficients in AD was smaller than that of NC but there was no significant difference (z = 1.81, not significant). We further observed that the AD patients had significantly disrupted structural connectivity. We also show that the coordinated variance of cortical thickness is distributed more randomly from one region to other regions in AD patients when compared to NC subjects. Our proposed SCN may provide surface-based measures for understanding interaction between two brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC

  16. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients.

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E; Kim, Hee Jin; Na, Duk L; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are "small world." There were significant difference between NC and AD group in characteristic path lengths (z = -2.97, p < 0.01) and small-worldness values (z = 4.05, p < 0.01). Clustering coefficients in AD was smaller than that of NC but there was no significant difference (z = 1.81, not significant). We further observed that the AD patients had significantly disrupted structural connectivity. We also show that the coordinated variance of cortical thickness is distributed more randomly from one region to other regions in AD patients when compared to NC subjects. Our proposed SCN may provide surface-based measures for understanding interaction between two brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC

  17. Assessing brain structural associations with working memory related brain patterns in schizophrenia and healthy controls using linked independent component analysis

    Directory of Open Access Journals (Sweden)

    Christine Lycke Brandt

    2015-01-01

    Full Text Available Schizophrenia (SZ is a psychotic disorder with significant cognitive dysfunction. Abnormal brain activation during cognitive processing has been reported, both in task-positive and task-negative networks. Further, structural cortical and subcortical brain abnormalities have been documented, but little is known about how task-related brain activation is associated with brain anatomy in SZ compared to healthy controls (HC. Utilizing linked independent component analysis (LICA, a data-driven multimodal analysis approach, we investigated structure–function associations in a large sample of SZ (n = 96 and HC (n = 142. We tested for associations between task-positive (fronto-parietal and task-negative (default-mode brain networks derived from fMRI activation during an n-back working memory task, and brain structural measures of surface area, cortical thickness, and gray matter volume, and to what extent these associations differed in SZ compared to HC. A significant association (p < .05, corrected for multiple comparisons was found between a component reflecting the task-positive fronto-parietal network and another component reflecting cortical thickness in fronto-temporal brain regions in SZ, indicating increased activation with increased thickness. Other structure–function associations across, between and within groups were generally moderate and significant at a nominal p-level only, with more numerous and stronger associations in SZ compared to HC. These results indicate a complex pattern of moderate associations between brain activation during cognitive processing and brain morphometry, and extend previous findings of fronto-temporal brain abnormalities in SZ by suggesting a coupling between cortical thickness of these brain regions and working memory-related brain activation.

  18. Analytical Operations Relate Structural and Functional Connectivity in the Brain

    Science.gov (United States)

    Saggio, Maria Luisa; Ritter, Petra; Jirsa, Viktor K.

    2016-01-01

    Resting-state large-scale brain models vary in the amount of biological elements they incorporate and in the way they are being tested. One might expect that the more realistic the model is, the closer it should reproduce real functional data. It has been shown, instead, that when linear correlation across long BOLD fMRI time-series is used as a measure for functional connectivity (FC) to compare simulated and real data, a simple model performs just as well, or even better, than more sophisticated ones. The model in question is a simple linear model, which considers the physiological noise that is pervasively present in our brain while it diffuses across the white-matter connections, that is structural connectivity (SC). We deeply investigate this linear model, providing an analytical solution to straightforwardly compute FC from SC without the need of computationally costly simulations of time-series. We provide a few examples how this analytical solution could be used to perform a fast and detailed parameter exploration or to investigate resting-state non-stationarities. Most importantly, by inverting the analytical solution, we propose a method to retrieve information on the anatomical structure directly from functional data. This simple method can be used to complement or guide DTI/DSI and tractography results, especially for a better assessment of inter-hemispheric connections, or to provide an estimate of SC when only functional data are available. PMID:27536987

  19. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.

    Science.gov (United States)

    Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios

    2013-07-31

    Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies.

  20. Online social network size is reflected in human brain structure.

    Science.gov (United States)

    Kanai, R; Bahrami, B; Roylance, R; Rees, G

    2012-04-01

    The increasing ubiquity of web-based social networking services is a striking feature of modern human society. The degree to which individuals participate in these networks varies substantially for reasons that are unclear. Here, we show a biological basis for such variability by demonstrating that quantitative variation in the number of friends an individual declares on a web-based social networking service reliably predicted grey matter density in the right superior temporal sulcus, left middle temporal gyrus and entorhinal cortex. Such regions have been previously implicated in social perception and associative memory, respectively. We further show that variability in the size of such online friendship networks was significantly correlated with the size of more intimate real-world social groups. However, the brain regions we identified were specifically associated with online social network size, whereas the grey matter density of the amygdala was correlated both with online and real-world social network sizes. Taken together, our findings demonstrate that the size of an individual's online social network is closely linked to focal brain structure implicated in social cognition. PMID:22012980

  1. A simulation model for analysing brain structure deformations

    Energy Technology Data Exchange (ETDEWEB)

    Bona, Sergio Di [Institute for Information Science and Technologies, Italian National Research Council (ISTI-8211-CNR), Via G Moruzzi, 1-56124 Pisa (Italy); Lutzemberger, Ludovico [Department of Neuroscience, Institute of Neurosurgery, University of Pisa, Via Roma, 67-56100 Pisa (Italy); Salvetti, Ovidio [Institute for Information Science and Technologies, Italian National Research Council (ISTI-8211-CNR), Via G Moruzzi, 1-56124 Pisa (Italy)

    2003-12-21

    Recent developments of medical software applications from the simulation to the planning of surgical operations have revealed the need for modelling human tissues and organs, not only from a geometric point of view but also from a physical one, i.e. soft tissues, rigid body, viscoelasticity, etc. This has given rise to the term 'deformable objects', which refers to objects with a morphology, a physical and a mechanical behaviour of their own and that reflects their natural properties. In this paper, we propose a model, based upon physical laws, suitable for the realistic manipulation of geometric reconstructions of volumetric data taken from MR and CT scans. In particular, a physically based model of the brain is presented that is able to simulate the evolution of different nature pathological intra-cranial phenomena such as haemorrhages, neoplasm, haematoma, etc and to describe the consequences that are caused by their volume expansions and the influences they have on the anatomical and neuro-functional structures of the brain.

  2. MR brain scan tissues and structures segmentation: local cooperative Markovian agents and Bayesian formulation

    International Nuclear Information System (INIS)

    Accurate magnetic resonance brain scan segmentation is critical in a number of clinical and neuroscience applications. This task is challenging due to artifacts, low contrast between tissues and inter-individual variability that inhibit the introduction of a priori knowledge. In this thesis, we propose a new MR brain scan segmentation approach. Unique features of this approach include (1) the coupling of tissue segmentation, structure segmentation and prior knowledge construction, and (2) the consideration of local image properties. Locality is modeled through a multi-agent framework: agents are distributed into the volume and perform a local Markovian segmentation. As an initial approach (LOCUS, Local Cooperative Unified Segmentation), intuitive cooperation and coupling mechanisms are proposed to ensure the consistency of local models. Structures are segmented via the introduction of spatial localization constraints based on fuzzy spatial relations between structures. In a second approach, (LOCUS-B, LOCUS in a Bayesian framework) we consider the introduction of a statistical atlas to describe structures. The problem is reformulated in a Bayesian framework, allowing a statistical formalization of coupling and cooperation. Tissue segmentation, local model regularization, structure segmentation and local affine atlas registration are then coupled in an EM framework and mutually improve. The evaluation on simulated and real images shows good results, and in particular, a robustness to non-uniformity and noise with low computational cost. Local distributed and cooperative MRF models then appear as a powerful and promising approach for medical image segmentation. (author)

  3. Long-lasting Consequences of Early Life Stress on Brain Structure, Emotion and Cognition

    NARCIS (Netherlands)

    H. Krugers; M. Joëls

    2014-01-01

    During the perinatal period, the brain undergoes substantial structural changes, synaptic rearrangements, and development of neuronal circuits which ultimately determine brain function and behavior. Environmental factors-such as exposure to adverse experiences-have major impact on brain function and

  4. Safety and Efficacy of Cerebrolysin in Infants with Communication Defects due to Severe Perinatal Brain Insult: A Randomized Controlled Clinical Trial

    OpenAIRE

    Hassanein, Sahar M.A.; Deifalla, Shaymaa M.; El-Houssinie, Moustafa; Mokbel, Somaia A.

    2015-01-01

    Background and Purpose The neuroregenerative drug Cerebrolysin has demonstrated efficacy in improving cognition in adults with stroke and Alzheimer's disease. The aim of this study was to determine the efficacy and safety of Cerebrolysin in the treatment of communication defects in infants with severe perinatal brain insult. Methods A randomized placebo-controlled clinical trial was conducted in which 158 infants (age 6-21 months) with communication defects due to severe perinatal brain insul...

  5. Changes in Brain Metallome/Metabolome Pattern due to a Single i.v. Injection of Manganese in Rats

    Science.gov (United States)

    Neth, Katharina; Lucio, Marianna; Walker, Alesia; Zorn, Julia; Schmitt-Kopplin, Philippe; Michalke, Bernhard

    2015-01-01

    Exposure to high concentrations of Manganese (Mn) is known to potentially induce an accumulation in the brain, leading to a Parkinson related disease, called manganism. Versatile mechanisms of Mn-induced brain injury are discussed, with inactivation of mitochondrial defense against oxidative stress being a major one. So far, studies indicate that the main Mn-species entering the brain are low molecular mass (LMM) compounds such as Mn-citrate. Applying a single low dose MnCl2 injection in rats, we observed alterations in Mn-species pattern within the brain by analysis of aqueous brain extracts by size-exclusion chromatography—inductively coupled plasma mass spectrometry (SEC-ICP-MS). Additionally, electrospray ionization—ion cyclotron resonance-Fourier transform-mass spectrometry (ESI-ICR/FT-MS) measurement of methanolic brain extracts revealed a comprehensive analysis of changes in brain metabolisms after the single MnCl2 injection. Major alterations were observed for amino acid, fatty acid, glutathione, glucose and purine/pyrimidine metabolism. The power of this metabolomic approach is the broad and detailed overview of affected brain metabolisms. We also correlated results from the metallomic investigations (Mn concentrations and Mn-species in brain) with the findings from metabolomics. This strategy might help to unravel the role of different Mn-species during Mn-induced alterations in brain metabolism. PMID:26383269

  6. Post-mortem Findings in Huntington’s Deep Brain Stimulation: A Moving Target Due to Atrophy

    OpenAIRE

    Vedam-Mai, Vinata; Martinez-Ramirez, Daniel; Hilliard, Justin D.; Carbunaru, Samuel; Yachnis, Anthony T.; Bloom, Joshua; Keeling, Peyton; Awe, Lisa; Foote, Kelly D.; Okun, Michael S.

    2016-01-01

    Background Deep brain stimulation (DBS) has been shown to be effective for Parkinson’s disease, essential tremor, and primary dystonia. However, mixed results have been reported in Huntington’s disease (HD). Case Report A single case of HD DBS was identified from the University of Florida DBS Brain Tissue Network. The clinical presentation, evolution, surgical planning, DBS parameters, clinical outcomes, and brain pathological changes are summarized. Discussion This case of HD DBS revealed th...

  7. Sport-related structural brain injury associated with arachnoid cysts: a systematic review and quantitative analysis.

    Science.gov (United States)

    Zuckerman, Scott L; Prather, Colin T; Yengo-Kahn, Aaron M; Solomon, Gary S; Sills, Allen K; Bonfield, Christopher M

    2016-04-01

    OBJECTIVE Arachnoid cysts (ACs) are congenital lesions bordered by an arachnoid membrane. Researchers have postulated that individuals with an AC demonstrate a higher rate of structural brain injury after trauma. Given the potential neurological consequences of a structural brain injury requiring neurosurgical intervention, the authors sought to perform a systematic review of sport-related structural-brain injury associated with ACs with a corresponding quantitative analysis. METHODS Titles and abstracts were searched systematically across the following databases: PubMed, Embase, CINAHL, and PsycINFO. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Peer-reviewed case reports, case series, or observational studies that reported a structural brain injury due to a sport or recreational activity (hereafter referred to as sport-related) with an associated AC were included. Patients were excluded if they did not have an AC, suffered a concussion without structural brain injury, or sustained the injury during a non-sport-related activity (e.g., fall, motor vehicle collision). Descriptive statistical analysis and time to presentation data were summarized. Univariate logistic regression models to assess predictors of neurological deficit, open craniotomy, and cystoperitoneal shunt were completed. RESULTS After an initial search of 994 original articles, 52 studies were found that reported 65 cases of sport-related structural brain injury associated with an AC. The median age at presentation was 16 years (range 4-75 years). Headache was the most common presenting symptom (98%), followed by nausea and vomiting in 49%. Thirteen patients (21%) presented with a neurological deficit, most commonly hemiparesis. Open craniotomy was the most common form of treatment (49%). Bur holes and cyst fenestration were performed in 29 (45%) and 31 (48%) patients, respectively. Seven patients (11%) received

  8. High-resolution anatomy of the human brain stem using 7-T MRI: improved detection of inner structures and nerves?

    International Nuclear Information System (INIS)

    The purpose of this paper is to assess the value of 7 Tesla (7 T) MRI for the depiction of brain stem and cranial nerve (CN) anatomy. Six volunteers were examined at 7 T using high-resolution SWI, MPRAGE, MP2RAGE, 3D SPACE T2, T2, and PD images to establish scanning parameters targeted at optimizing spatial resolution. Direct comparisons between 3 and 7 T were performed in two additional subjects using the finalized sequences (3 T: T2, PD, MPRAGE, SWAN; 7 T: 3D T2, MPRAGE, SWI, MP2RAGE). Artifacts and the depiction of structures were evaluated by two neuroradiologists using a standardized score sheet. Sequences could be established for high-resolution 7 T imaging even in caudal cranial areas. High in-plane resolution T2, PD, and SWI images provided depiction of inner brain stem structures such as pons fibers, raphe, reticular formation, nerve roots, and periaqueductal gray. MPRAGE and MP2RAGE provided clear depiction of the CNs. 3D T2 images improved depiction of inner brain structure in comparison to T2 images at 3 T. Although the 7-T SWI sequence provided improved contrast to some inner structures, extended areas were influenced by artifacts due to image disturbances from susceptibility differences. Seven-tesla imaging of basal brain areas is feasible and might have significant impact on detection and diagnosis in patients with specific diseases, e.g., trigeminal pain related to affection of the nerve root. Some inner brain stem structures can be depicted at 3 T, but certain sequences at 7 T, in particular 3D SPACE T2, are superior in producing anatomical in vivo images of deep brain stem structures. (orig.)

  9. High-resolution anatomy of the human brain stem using 7-T MRI: improved detection of inner structures and nerves?

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, Elke R. [Medical University Innsbruck, Department of Neuroradiology, Innsbruck (Austria); Maderwald, Stefan [University Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); Linn, Jennifer; Bochmann, Katja [LMU Munich, Department of Neuroradiology, Munich (Germany); Dassinger, Benjamin [Medical University Innsbruck, Department of Neuroradiology, Innsbruck (Austria); Justus-Liebig-University Giessen, Department of Neuroradiology, Giessen (Germany); Forsting, Michael [University Hospital, University Duisburg-Essen, Departments of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Ladd, Mark E. [University Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); University Hospital, University Duisburg-Essen, Departments of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2014-03-15

    The purpose of this paper is to assess the value of 7 Tesla (7 T) MRI for the depiction of brain stem and cranial nerve (CN) anatomy. Six volunteers were examined at 7 T using high-resolution SWI, MPRAGE, MP2RAGE, 3D SPACE T2, T2, and PD images to establish scanning parameters targeted at optimizing spatial resolution. Direct comparisons between 3 and 7 T were performed in two additional subjects using the finalized sequences (3 T: T2, PD, MPRAGE, SWAN; 7 T: 3D T2, MPRAGE, SWI, MP2RAGE). Artifacts and the depiction of structures were evaluated by two neuroradiologists using a standardized score sheet. Sequences could be established for high-resolution 7 T imaging even in caudal cranial areas. High in-plane resolution T2, PD, and SWI images provided depiction of inner brain stem structures such as pons fibers, raphe, reticular formation, nerve roots, and periaqueductal gray. MPRAGE and MP2RAGE provided clear depiction of the CNs. 3D T2 images improved depiction of inner brain structure in comparison to T2 images at 3 T. Although the 7-T SWI sequence provided improved contrast to some inner structures, extended areas were influenced by artifacts due to image disturbances from susceptibility differences. Seven-tesla imaging of basal brain areas is feasible and might have significant impact on detection and diagnosis in patients with specific diseases, e.g., trigeminal pain related to affection of the nerve root. Some inner brain stem structures can be depicted at 3 T, but certain sequences at 7 T, in particular 3D SPACE T2, are superior in producing anatomical in vivo images of deep brain stem structures. (orig.)

  10. Age-related changes in brain structural covariance networks

    Directory of Open Access Journals (Sweden)

    Xinwei eLi

    2013-03-01

    Full Text Available Previous neuroimaging studies have suggested that cerebral changes over normal aging are not simply characterized by regional alterations, but rather by the reorganization of cortical connectivity patterns. The investigation of structural covariance networks (SCNs using voxel-based morphometry is an advanced approach to examining the pattern of covariance in gray matter volumes among different regions of the human cortex. To date, how the organization of critical SCNs change during normal aging remains largely unknown. In this study, we used an SCN mapping approach to investigate eight large-scale networks in 240 healthy participants aged 18–89 years. These participants were subdivided into young (18–23 years, middle aged (30–58 years, and older (61–89 years subjects. Eight seed regions were chosen from widely reported functional intrinsic connectivity networks. The voxels showing significant positive associations with these seed regions were used to describe the topological organization of an SCN. All of these networks exhibited non-linear patterns in their spatial extent that were associated with normal aging. These networks, except the primary motor network, had a distributed topology in young participants, a sharply localized topology in middle aged participants, and were relatively stable in older participants. The structural covariance derived using the primary motor cortex was limited to the ipsilateral motor regions in the young and older participants, but included contralateral homologous regions in the middle aged participants. In addition, there were significant between-group differences in the structural networks associated with language-related speech and semantics processing, executive control, and the default-mode network. Taken together, the results of this study demonstrate age-related changes in the topological organization of SCNs, and provide insights into normal aging of the human brain.

  11. Spectral properties of the temporal evolution of brain network structure

    Science.gov (United States)

    Wang, Rong; Zhang, Zhen-Zhen; Ma, Jun; Yang, Yong; Lin, Pan; Wu, Ying

    2015-12-01

    The temporal evolution properties of the brain network are crucial for complex brain processes. In this paper, we investigate the differences in the dynamic brain network during resting and visual stimulation states in a task-positive subnetwork, task-negative subnetwork, and whole-brain network. The dynamic brain network is first constructed from human functional magnetic resonance imaging data based on the sliding window method, and then the eigenvalues corresponding to the network are calculated. We use eigenvalue analysis to analyze the global properties of eigenvalues and the random matrix theory (RMT) method to measure the local properties. For global properties, the shifting of the eigenvalue distribution and the decrease in the largest eigenvalue are linked to visual stimulation in all networks. For local properties, the short-range correlation in eigenvalues as measured by the nearest neighbor spacing distribution is not always sensitive to visual stimulation. However, the long-range correlation in eigenvalues as evaluated by spectral rigidity and number variance not only predicts the universal behavior of the dynamic brain network but also suggests non-consistent changes in different networks. These results demonstrate that the dynamic brain network is more random for the task-positive subnetwork and whole-brain network under visual stimulation but is more regular for the task-negative subnetwork. Our findings provide deeper insight into the importance of spectral properties in the functional brain network, especially the incomparable role of RMT in revealing the intrinsic properties of complex systems.

  12. Spectral properties of the temporal evolution of brain network structure.

    Science.gov (United States)

    Wang, Rong; Zhang, Zhen-Zhen; Ma, Jun; Yang, Yong; Lin, Pan; Wu, Ying

    2015-12-01

    The temporal evolution properties of the brain network are crucial for complex brain processes. In this paper, we investigate the differences in the dynamic brain network during resting and visual stimulation states in a task-positive subnetwork, task-negative subnetwork, and whole-brain network. The dynamic brain network is first constructed from human functional magnetic resonance imaging data based on the sliding window method, and then the eigenvalues corresponding to the network are calculated. We use eigenvalue analysis to analyze the global properties of eigenvalues and the random matrix theory (RMT) method to measure the local properties. For global properties, the shifting of the eigenvalue distribution and the decrease in the largest eigenvalue are linked to visual stimulation in all networks. For local properties, the short-range correlation in eigenvalues as measured by the nearest neighbor spacing distribution is not always sensitive to visual stimulation. However, the long-range correlation in eigenvalues as evaluated by spectral rigidity and number variance not only predicts the universal behavior of the dynamic brain network but also suggests non-consistent changes in different networks. These results demonstrate that the dynamic brain network is more random for the task-positive subnetwork and whole-brain network under visual stimulation but is more regular for the task-negative subnetwork. Our findings provide deeper insight into the importance of spectral properties in the functional brain network, especially the incomparable role of RMT in revealing the intrinsic properties of complex systems. PMID:26723151

  13. Simulating ‘structure-function’ patterns of malignant brain tumors

    Science.gov (United States)

    Mansury, Yuri; Deisboeck, Thomas S.

    2004-01-01

    Rapid growth and extensive tissue infiltration are characteristics of highly malignant neuroepithelial brain tumors. Very little is known, however, about the existence of structure-function relationships in these types of neoplasm. Therefore, using a previously developed two-dimensional agent-based model, we have investigated the emergent patterns of multiple tumor cells that proliferate and migrate on an adaptive grid lattice, driven by a local-search mechanism and guided by the presence of distinct environmental conditions. Numerical results indicate a strong correlation between the fractal dimensions of the tumor surface and the average velocity of the tumor's spatial expansion. In particular, when the so called ‘beaten-path advantage’ intensifies, i.e., rising ‘mechanical rewards’ for cells to follow each other along preformed pathways, it results in an increase of the tumor system's fractal dimensions leading to a concomitant acceleration of its spatial expansion. Whereas cell migration is the dominant phenotype responsible for the more extensive branching patterns exhibiting higher fractal dimensions, cell proliferation appears to become more active primarily at lower fracticality associated with stronger mechanical confinements. Implications of these results for experimental and clinical cancer research are discussed.

  14. Structural brain imaging in diabetes : A methodological perspective

    NARCIS (Netherlands)

    Jongen, Cynthia; Biessels, Geert Jan

    2008-01-01

    Brain imaging provides information on brain anatomy and function and progression of cerebral abnormalities can be monitored. This may provide insight into the aetiology of diabetes related cerebral disorders. This paper focuses on the methods for the assessment of white matter hyperintensities and b

  15. Structural development of human brain white matter from mid-fetal to perinatal stage

    Science.gov (United States)

    Ouyang, Austin; Yu, Qiaowen; Mishra, Virendra; Chalak, Lina; Jeon, Tina; Sivarajan, Muraleedharan; Jackson, Greg; Rollins, Nancy; Liu, Shuwei; Huang, Hao

    2015-03-01

    The structures of developing human brain white matter (WM) tracts can be effectively quantified by DTI-derived metrics, including fractional anisotropy (FA), mean, axial and radial diffusivity (MD, AD and RD). However, dynamics of WM microstructure during very early developmental period from mid-fetal to perinatal stage is unknown. It is difficult to accurately measure microstructural properties of these WM tracts due to severe contamination from cerebrospinal fluid (CSF). In this study, high resolution DTI of fetal brains at mid-fetal stage (20 weeks of gestation or 20wg), 19 brains in the middle of 3rd trimester (35wg) and 17 brains around term (40wg) were acquired. We established first population-averaged DTI templates at these three time points and extracted WM skeleton. 16 major WM tracts in limbic, projection, commissural and association tract groups were traced with DTI tractography in native space. The WM skeleton in the template space was inversely transformed back to the native space for measuring core WM microstructures of each individual tract. Continuous microstructural enhancement and volumetric increase of WM tracts were found from 20wg to 40wg. The microstructural enhancement from FA measurement is decelerated in late 3rd trimester compared to mid-fetal to middle 3rd trimester, while volumetric increase of prefrontal WM tracts is accelerated. The microstructural enhancement from 35wg to 40wg is heterogeneous among different tract groups with microstructures of association tracts undergoing most dramatic change. Besides decreases of RD indicating active myelination, the decrease of AD for most WM tracts during late 3rd trimester suggests axonal packing process.

  16. A Comparative Study of Theoretical Graph Models for Characterizing Structural Networks of Human Brain

    Directory of Open Access Journals (Sweden)

    Xiaojin Li

    2013-01-01

    Full Text Available Previous studies have investigated both structural and functional brain networks via graph-theoretical methods. However, there is an important issue that has not been adequately discussed before: what is the optimal theoretical graph model for describing the structural networks of human brain? In this paper, we perform a comparative study to address this problem. Firstly, large-scale cortical regions of interest (ROIs are localized by recently developed and validated brain reference system named Dense Individualized Common Connectivity-based Cortical Landmarks (DICCCOL to address the limitations in the identification of the brain network ROIs in previous studies. Then, we construct structural brain networks based on diffusion tensor imaging (DTI data. Afterwards, the global and local graph properties of the constructed structural brain networks are measured using the state-of-the-art graph analysis algorithms and tools and are further compared with seven popular theoretical graph models. In addition, we compare the topological properties between two graph models, namely, stickiness-index-based model (STICKY and scale-free gene duplication model (SF-GD, that have higher similarity with the real structural brain networks in terms of global and local graph properties. Our experimental results suggest that among the seven theoretical graph models compared in this study, STICKY and SF-GD models have better performances in characterizing the structural human brain network.

  17. Brain glucose metabolic changes associated with chronic spontaneous Pain due to brachial plexus avulsion:a preliminary positron emission tomography study

    Institute of Scientific and Technical Information of China (English)

    CHEN Fu-yong; TAO Wei; CHENG Xin; WANG Hong-yan; HU Yong-sheng; ZHANG Xiao-hua; LI Yong-jie

    2008-01-01

    Background Previous brain imaging studies suggested that the brain activity underlying the perception of chronic pain maV differ from that underlying acute pain.To investigate the brain regions involved in chronic spontaneous pain due to brachial plexus avulsion(BPA),fluorine-18fluorodeoxygIucose (19F-FDG) positron emission tomography (PET) scanning was applied to determine the glucose metabolic changes in patients with pain due to BPA.Methods Six right-handed patients with chronic spontaneous pain due to left-BPA and twelve right-handed age-and sex-matched healthy control subjects participated in the 18F-FDG PET study.The patients were rated by visual analog scale (VAS) during scanning and Hamilton depression scale and Hamilton anxiety scale after scanning.Statistical parametric mapping 2 (SPM2) was applied for data analysis.Results Compared with healthy subjects,the patients had significant glucose metabolism decreases in the right thalamus and S I(P<0.001,uncorrected),and significant glucose metabolism increases in the right orbitofrontaI cortex (OFC) (BA11),left rostral insula cortex and left dorsolateral prefrontal codex (DLPFC) (BA10/46) (P<0.001,uncorrected).Conclusion These findings suggest that the brain areas involved in emotion.aRention and internal modulation of pain may be related to the chronic spontaneous pain due to BPA.

  18. Brain Structural Integrity and Intrinsic Functional Connectivity Forecast 6 Year Longitudinal Growth in Children's Numerical Abilities

    OpenAIRE

    Evans, Tanya M.; Kochalka, John; Ngoon, Tricia J.; Wu, Sarah S.; Qin, Shaozheng; Battista, Christian; Menon, Vinod

    2015-01-01

    Early numerical proficiency lays the foundation for acquiring quantitative skills essential in today's technological society. Identification of cognitive and brain markers associated with long-term growth of children's basic numerical computation abilities is therefore of utmost importance. Previous attempts to relate brain structure and function to numerical competency have focused on behavioral measures from a single time point. Thus, little is known about the brain predictors of individual...

  19. Brain Structure Correlates of Urban Upbringing, an Environmental Risk Factor for Schizophrenia

    OpenAIRE

    Haddad, Leila; Schäfer, Axel; Streit, Fabian; Lederbogen, Florian; Grimm, Oliver; Wüst, Stefan; Deuschle, Michael; Kirsch, Peter; Tost, Heike; Meyer-Lindenberg, Andreas

    2014-01-01

    Urban upbringing has consistently been associated with schizophrenia, but which specific environmental exposures are reflected by this epidemiological observation and how they impact the developing brain to increase risk is largely unknown. On the basis of prior observations of abnormal functional brain processing of social stress in urban-born humans and preclinical evidence for enduring structural brain effects of early social stress, we investigated a possible morphological correlate of ur...

  20. Neuroinflammation and structural injury of the fetal ovine brain following intra-amniotic Candida albicans exposure

    OpenAIRE

    Ophelders, Daan R. M. G.; Gussenhoven, Ruth; Lammens, Martin; Küsters, Benno; Kemp, Matthew W.; Newnham, John P; Payne, Matthew S.; Suhas G Kallapur; Jobe, Allan H.; Zimmermann, Luc J.; Boris W Kramer; Tim G A M Wolfs

    2016-01-01

    Background Intra-amniotic Candida albicans (C. Albicans) infection is associated with preterm birth and high morbidity and mortality rates. Survivors are prone to adverse neurodevelopmental outcomes. The mechanisms leading to these adverse neonatal brain outcomes remain largely unknown. To better understand the mechanisms underlying C. albicans-induced fetal brain injury, we studied immunological responses and structural changes of the fetal brain in a well-established translational ovine mod...

  1. Effects of alcohol intake on brain structure and function in non-alcohol-dependent drinkers

    OpenAIRE

    Bruin, Eveline Astrid de

    2005-01-01

    About 85% of the adult population in the Netherlands regularly drinks alcohol. Chronic excessive alcohol intake in alcohol-dependent individuals is known to have damaging effects on brain structure and function. Relatives of alcohol-dependent individuals display differences in brain function that are similar to those found in alcoholics, even if they have never been drinking alcohol. This suggests that brain damage in alcohol-dependent individuals is at least partly related to genetic factors...

  2. The Energy Landscape of Neurophysiological Activity Implicit in Brain Network Structure

    OpenAIRE

    Gu, Shi; Cieslak, Matthew; Baird, Benjamin; Muldoon, Sarah F.; Grafton, Scott T; Pasqualetti, Fabio; Danielle S Bassett

    2016-01-01

    A critical mystery in neuroscience lies in determining how anatomical structure impacts the complex functional dynamics of human thought. How does large-scale brain circuitry constrain states of neuronal activity and transitions between those states? We address these questions using a maximum entropy model of brain dynamics informed by white matter tractography. We demonstrate that the most probable brain states -- characterized by minimal energy -- display common activation profiles across b...

  3. Structural Brain Network Disturbances in the Psychosis Spectrum

    NARCIS (Netherlands)

    van Dellen, Edwin; Bohlken, Marc M; Draaisma, Laurijn; Tewarie, Prejaas K; van Lutterveld, Remko; Mandl, René; Stam, Cornelis J; Sommer, Iris E

    2016-01-01

    BACKGROUND: Individuals with subclinical psychotic symptoms provide a unique window on the pathophysiology of psychotic experiences as these individuals are free of confounders such as hospitalization, negative and cognitive symptoms and medication use. Brain network disturbances of white matter con

  4. Dimensional errors in LIGA-produced metal structures due to thermal expansion and swelling of PMMA.

    Energy Technology Data Exchange (ETDEWEB)

    Kistler, Bruce L.; Dryden, Andrew S.; Crowell, Jeffrey A.W.; Griffiths, Stewart K.

    2004-04-01

    Numerical methods are used to examine dimensional errors in metal structures microfabricated by the LIGA process. These errors result from elastic displacements of the PMMA mold during electrodeposition and arise from thermal expansion of the PMMA when electroforming is performed at elevated temperatures and from PMMA swelling due to absorption of water from aqueous electrolytes. Both numerical solutions and simple analytical approximations describing PMMA displacements for idealized linear and axisymmetric geometries are presented and discussed. We find that such displacements result in tapered metal structures having sidewall slopes up to 14 {micro}m per millimeter of height for linear structures bounded by large areas of PMMA. Tapers for curved structures are of similar magnitude, but these structures are additionally skewed from the vertical. Potential remedies for reducing dimensional errors are also discussed. Here we find that auxiliary moat-like features patterned into the PMMA surrounding mold cavities can reduce taper by an order of magnitude or more. Such moats dramatically reduce tapers for all structures, but increase skew for curved structures when the radius of curvature is comparable to the structure height.

  5. Structural brain abnormalities in early onset first-episode psychosis

    DEFF Research Database (Denmark)

    Pagsberg, A K; Baaré, William Frans Christian; Raabjerg Christensen, A M;

    2007-01-01

    BACKGROUND: Brain morphometry in children and adolescents with first-episode psychosis offer a unique opportunity for pathogenetic investigations. METHODS: We compared high-resolution 3D T1-weighted magnetic resonance images of the brain in 29 patients (schizophrenia, schizotypal disorder, delusi...... already at illness onset in young schizophrenia spectrum patients, suggests aberrant neurodevelopmental processes in the pathogenesis of these disorders. Gray matter volume changes, however, appear not to be a key feature in early onset first-episode psychosis....

  6. A novel brain partition highlights the modular skeleton shared by structure and function.

    Science.gov (United States)

    Diez, Ibai; Bonifazi, Paolo; Escudero, Iñaki; Mateos, Beatriz; Muñoz, Miguel A; Stramaglia, Sebastiano; Cortes, Jesus M

    2015-01-01

    Elucidating the intricate relationship between brain structure and function, both in healthy and pathological conditions, is a key challenge for modern neuroscience. Recent progress in neuroimaging has helped advance our understanding of this important issue, with diffusion images providing information about structural connectivity (SC) and functional magnetic resonance imaging shedding light on resting state functional connectivity (rsFC). Here, we adopt a systems approach, relying on modular hierarchical clustering, to study together SC and rsFC datasets gathered independently from healthy human subjects. Our novel approach allows us to find a common skeleton shared by structure and function from which a new, optimal, brain partition can be extracted. We describe the emerging common structure-function modules (SFMs) in detail and compare them with commonly employed anatomical or functional parcellations. Our results underline the strong correspondence between brain structure and resting-state dynamics as well as the emerging coherent organization of the human brain.

  7. Effect of Growth Hormone Deficiency on Brain Structure, Motor Function and Cognition

    Science.gov (United States)

    Webb, Emma A.; O'Reilly, Michelle A.; Clayden, Jonathan D.; Seunarine, Kiran K.; Chong, Wui K.; Dale, Naomi; Salt, Alison; Clark, Chris A.; Dattani, Mehul T.

    2012-01-01

    The growth hormone-insulin-like growth factor-1 axis plays a role in normal brain growth but little is known of the effect of growth hormone deficiency on brain structure. Children with isolated growth hormone deficiency (peak growth hormone less than 6.7 [micro]g/l) and idiopathic short stature (peak growth hormone greater than 10 [micro]g/l)…

  8. Effects of alcohol intake on brain structure and function in non-alcohol-dependent drinkers

    NARCIS (Netherlands)

    Bruin, Eveline Astrid de

    2005-01-01

    About 85% of the adult population in the Netherlands regularly drinks alcohol. Chronic excessive alcohol intake in alcohol-dependent individuals is known to have damaging effects on brain structure and function. Relatives of alcohol-dependent individuals display differences in brain function that ar

  9. Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques.

    Science.gov (United States)

    Bigler, Erin D

    2015-09-01

    Magnetic resonance imaging (MRI) of the brain provides exceptional image quality for visualization and neuroanatomical classification of brain structure. A variety of image analysis techniques provide both qualitative as well as quantitative methods to relate brain structure with neuropsychological outcome and are reviewed herein. Of particular importance are more automated methods that permit analysis of a broad spectrum of anatomical measures including volume, thickness and shape. The challenge for neuropsychology is which metric to use, for which disorder and the timing of when image analysis methods are applied to assess brain structure and pathology. A basic overview is provided as to the anatomical and pathoanatomical relations of different MRI sequences in assessing normal and abnormal findings. Some interpretive guidelines are offered including factors related to similarity and symmetry of typical brain development along with size-normalcy features of brain anatomy related to function. The review concludes with a detailed example of various quantitative techniques applied to analyzing brain structure for neuropsychological outcome studies in traumatic brain injury.

  10. Influence of the lateral ventricles and irregular skull base on brain kinematics due to sagittal plane head rotation.

    Science.gov (United States)

    Ivarsson, J; Viano, D C; Lövsund, P

    2002-08-01

    Two-dimensional physical models of the human head were used to investigate how the lateral ventricles and irregular skull base influence kinematics in the medial brain during sagittal angular head dynamics. Silicone gel simulated the brain and was separatedfrom the surrounding skull vessel by paraffin that provided a slip interface between the gel and vessel. A humanlike skull base model (HSB) included a surrogate skull base mimicking the irregular geometry of the human. An HSBV model added an elliptical inclusion filled with liquid paraffin simulating the lateral ventricles to the HSB model. A simplified skull base model (SSBV) included ventricle substitute but approximated the anterior and middle cranial fossae by a flat and slightly angled surface. The models were exposed to 7600 rad/s2 peak angular acceleration with 6 ms pulse duration and 5 deg forced rotation. After 90 deg free rotation, the models were decelerated during 30 ms. Rigid body displacement, shear strain and principal strains were determined from high-speed video recorded trajectories of grid markers in the surrogate brains. Peak values of inferior brain surface displacement and strains were up to 10.9X (times) and 3.3X higher in SSBV than in HSBV. Peak strain was up to 2.7X higher in HSB than in HSBV. The results indicate that the irregular skull base protects nerves and vessels passing through the cranial floor by reducing brain displacement and that the intraventricular cerebrospinal fluid relieves strain in regions inferior and superior to the ventricles. The ventricles and irregular skull base are necessary in modeling head impact and understanding brain injury mechanisms. PMID:12188208

  11. Brain SCALE: brain structure and cognition: an adolescent longitudinal twin study into the genetic etiology of individual differences.

    Science.gov (United States)

    van Soelen, Inge L C; Brouwer, Rachel M; Peper, Jiska S; van Leeuwen, Marieke; Koenis, Marinka M G; van Beijsterveldt, Toos C E M; Swagerman, Suzanne C; Kahn, René S; Hulshoff Pol, Hilleke E; Boomsma, Dorret I

    2012-06-01

    From childhood into adolescence, the child's brain undergoes considerable changes in both structure and function. Twin studies are of great value to explore to what extent genetic and environmental factors explain individual differences in brain development and cognition. In The Netherlands, we initiated a longitudinal study in which twins, their siblings and their parents are assessed at three year intervals. The participants were recruited from The Netherlands Twin Register (NTR) and at baseline consisted of 112 families, with 9-year-old twins and an older sibling. Three years later, 89 families returned for follow-up assessment. Data collection included psychometric IQ tests, a comprehensive neuropsychological testing protocol, and parental and self-ratings of behavioral and emotional problems. Physical maturation was measured through assessment of Tanner stages. Hormonal levels (cortisol, luteinizing hormone, follicle-stimulating hormone, testosterone, and estrogens) were assessed in urine and saliva. Brain scans were acquired using 1.5 Tesla Magnetic Resonance Imaging (MRI), which provided volumetric measures and measures of cortical thickness. Buccal swabs were collected for DNA isolation for future candidate gene and genome-wide analysis studies. This article gives an overview of the study and the main findings. Participants will return for a third assessment when the twins are around 16 years old. Longitudinal twin-sibling studies that map brain development and cognitive function at well-defined ages aid in the understanding of genetic influences on normative brain development.

  12. Structural connectivity of the anterior cingulate in children with unilateral cerebral palsy due to white matter lesions.

    Science.gov (United States)

    Scheck, Simon M; Pannek, Kerstin; Raffelt, David A; Fiori, Simona; Boyd, Roslyn N; Rose, Stephen E

    2015-01-01

    In this work we investigate the structural connectivity of the anterior cingulate cortex (ACC) and its link with impaired executive function in children with unilateral cerebral palsy (UCP) due to periventricular white matter lesions. Fifty two children with UCP and 17 children with typical development participated in the study, and underwent diffusion and structural MRI. Five brain regions were identified for their high connectivity with the ACC using diffusion MRI fibre tractography: the superior frontal gyrus, medial orbitofrontal cortex, rostral middle frontal gyrus, precuneus and isthmus cingulate. Structural connectivity was assessed in pathways connecting these regions to the ACC using three diffusion MRI derived measures: fractional anisotropy (FA), mean diffusivity (MD) and apparent fibre density (AFD), and compared between participant groups. Furthermore we investigated correlations of these measures with executive function as assessed by the Flanker task. The ACC-precuneus tract had significantly different MD (p < 0.0001) and AFD (p = 0.0072) between groups, with post-hoc analysis showing significantly increased MD in the right hemisphere of children with left hemiparesis compared with controls. The ACC-superior frontal gyrus tract had significantly different FA (p = 0.0049) and MD (p = 0.0031) between groups. AFD in this tract (contralateral to side of hemiparesis; right hemisphere in controls) showed a significant relationship with Flanker task performance (p = 0.0045, β = -0.5856), suggesting that reduced connectivity correlates with executive dysfunction. Reduced structural integrity of ACC tracts appears to be important in UCP, in particular the connection to the superior frontal gyrus. Although damage to this area is heterogeneous it may be important in early identification of children with impaired executive function. PMID:26640762

  13. Multiple abscesses of the left brain hemisphere due to Listeria monocytogenes in an immunocompromised patient: a case report.

    Science.gov (United States)

    Matera, Giovanni; Puccio, Rossana; Giancotti, Aida; Quirino, Angela; Guadagnino, Vincenzo; Pardatscher, Kurt; Caroleo, Santo; De Rose, Marisa; Amorosi, Andrea; Liberto, Maria Carla; Focà, Alfredo

    2012-12-01

    We describe a case of brain abscesses in a cirrhotic and diabetic 57-year-old woman showing fever, aphasia, right hemiparesis and seizures. Neuroradiological investigation revealed unilateral cerebritis evolving in multiple abscesses. From blood and surgical drainage samples Listeria monocytogenes grew in pure culture. Despite decompressive craniotomy, the patient died two months after hospital admission. PMID:23299068

  14. The diminishing of crystal structure of Sn9Zn alloy due to electrical current stressing

    Energy Technology Data Exchange (ETDEWEB)

    He, Jian-Yang [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC (China); Lin, Kwang-Lung, E-mail: matkllin@mail.ncku.edu.tw [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan, ROC (China); Wu, Albert T. [Department of Chemical and Material Engineering, National Central University, Jhongli 32001, Taiwan, ROC (China)

    2015-01-15

    Highlights: • Electrical current stressing will diminish the XRD diffraction peaks of Sn9Zn alloy rapidly. • The kinetics of the diminishing of the crystalline peak follows a logarithmic law with respect to current density. • The diminishing of the XRD diffraction is believed to be a result of disruption of the crystal structure. - Abstract: The variations in the crystal structure of Sn9Zn alloy due to electrical current stressing were investigated with in situ synchrotron XRD analysis. The XRD (X-ray Diffraction) orientation peaks of both Sn and Zn crystals diminished rapidly upon current stressing. The behavior of peak diminishing indicated the electrodisruption of the crystal structure. The electrodisruption was correlated logarithmically to the strain, estimated from the XRD peak shift, as induced by current stressing. The peak diminishing of the Zn crystal was also ascribed to the electrodissolution of Zn in the Sn matrix as revealed by SEM image.

  15. Adolescent cocaine exposure causes enduring macroscale changes in mouse brain structure.

    Science.gov (United States)

    Wheeler, Anne L; Lerch, Jason P; Chakravarty, M Mallar; Friedel, Miriam; Sled, John G; Fletcher, Paul J; Josselyn, Sheena A; Frankland, Paul W

    2013-01-30

    Cocaine dependence is associated with abnormalities in brain structure in humans. However, it is unclear whether these differences in brain structure predispose an individual to drug use or are a result of cocaine's action on the brain. This study investigates the impact of chronic cocaine exposure on brain structure and drug-related behavior in mice. Specifically, mice received daily cocaine or saline injections for 20 d during two developmental time periods: adolescence (27-46 d old) and young adulthood (60-79 d old). Following 30 d of abstinence, either fixed brain T2 weighted magnetic resonance images were acquired on a 7 T scanner at 32 μm isotropic voxel dimensions or mice were assessed for sensitization to the locomotor stimulant effects of cocaine. Three automated techniques (deformation-based morphometry, striatum shape analysis, and cortical thickness assessment) were used to identify population differences in brain structure in cocaine-exposed versus saline-exposed mice. We found that cocaine induced changes in brain structure, and these were most pronounced in mice exposed to cocaine during adolescence. Many of these changes occurred in brain regions previously implicated in addiction including the nucleus accumbens, striatum, insular cortex, orbitofrontal cortex, and medial forebrain bundle. Furthermore, exposure to the same cocaine regimen caused sensitization to the locomotor stimulant effects of cocaine, and these effects were again more pronounced in mice exposed to cocaine during adolescence. These results suggest that altered brain structure following 1 month of abstinence may contribute to these persistent drug-related behaviors, and identify cocaine exposure as the cause of these morphological changes. PMID:23365219

  16. Mescaline-induced changes of brain-cortex ribosomes. Effect of mescaline on the hydrogen-bonded structure of ribonucleic acid of brain-cortex ribosomes.

    Science.gov (United States)

    Datta, R K; Ghosh, J J

    1970-05-01

    1. The action of mescaline sulphate on the hydrogen-bonded structure of the RNA constituent of ribosomes of goat brain-cortex slices was studied by using the hyperchromic effect of heating and formaldehyde reaction. 2. The ribosomal total RNA species of the mescaline-treated brain-cortex slices have a smaller proportion of hydrogen-bonded structure than the ribosomal RNA species of the untreated brain-cortex slices. 3. Mescaline also appears to have affected this lowering of hydrogen-bonded structure of the ribosomal 28S RNA of brain-cortex tissue.

  17. Brain structure in post-traumatic stress disorder: A voxel-based morphometry analysis

    OpenAIRE

    Tan, Liwen; Zhang, Li; Qi, Rongfeng; Lu, Guangming; Li, Lingjiang; Liu, Jun; Li, Weihui

    2013-01-01

    This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter v...

  18. Modular Segregation of Structural Brain Networks Supports the Development of Executive Function in Youth

    OpenAIRE

    Baum, Graham L.; Ciric, Rastko; Roalf, David R.; Richard F Betzel; Moore, Tyler M; Shinohara, Russel T.; Kahn, Ari E.; Quarmley, Megan; Cook, Philip A.; Elliot, Mark A.; Ruparel, Kosha; Gur, Raquel E; Gur, Ruben C.; Bassett, Danielle S.; Satterthwaite, Theodore D

    2016-01-01

    The human brain is organized into large-scale functional modules that have been shown to evolve in childhood and adolescence. However, it remains unknown whether structural brain networks are similarly refined during development, potentially allowing for improvements in executive function. In a sample of 882 participants (ages 8-22) who underwent diffusion imaging as part of the Philadelphia Neurodevelopmental Cohort, we demonstrate that structural network modules become more segregated with ...

  19. Maternal interpersonal affiliation is associated with adolescents' brain structure and reward processing

    OpenAIRE

    Schneider, S.; Brassen, S; Bromberg, U; Banaschewski, T; Conrod, P; Flor, H; Gallinat, J.; Garavan, Hugh; Heinz, A.; Martinot, J-L; Nees, F; Rietschel, M; Smolka, M N; Ströhle, A.; Struve, M

    2012-01-01

    Considerable animal and human research has been dedicated to the effects of parenting on structural brain development, focusing on hippocampal and prefrontal areas. Conversely, although functional imaging studies suggest that the neural reward circuitry is involved in parental affection, little is known about mothers' interpersonal qualities in relation to their children's brain structure and function. Moreover, gender differences concerning the effect of maternal qualities have rarely been i...

  20. Brain structure and the relationship with neurocognitive functioning in schizophrenia and bipolar disorder : MRI studies

    OpenAIRE

    2011-01-01

    Brain structural abnormalities as well as neurocognitive dysfunction, are found in schizophrenia and in bipolar disorder. Based on the fact that both brain structure and neurocognitive functioning are significantly heritable and affected in both schizophrenia and bipolar disorder, relationships between them are expected. However, previous studies report inconsistent findings. Also, schizophrenia and bipolar disorder are classified as separate disease entities, but demonstrate overlap with reg...

  1. Automatic Analysis of Brain Tissue and Structural Connectivity in MRI

    NARCIS (Netherlands)

    R. de Boer (Renske)

    2011-01-01

    textabstractStudies of the brain using magnetic resonance imaging (MRI) can provide insights in physiology and pathology that can eventually aid clinical diagnosis and therapy monitoring. MRI data acquired in these studies can be difficult, as well as laborious, to interpret and analyze by human obs

  2. Dehydration affects brain structure and function in healthy adolescents.

    Science.gov (United States)

    Kempton, Matthew J; Ettinger, Ulrich; Foster, Russell; Williams, Steven C R; Calvert, Gemma A; Hampshire, Adam; Zelaya, Fernando O; O'Gorman, Ruth L; McMorris, Terry; Owen, Adrian M; Smith, Marcus S

    2011-01-01

    It was recently observed that dehydration causes shrinkage of brain tissue and an associated increase in ventricular volume. Negative effects of dehydration on cognitive performance have been shown in some but not all studies, and it has also been reported that an increased perceived effort may be required following dehydration. However, the effects of dehydration on brain function are unknown. We investigated this question using functional magnetic resonance imaging (fMRI) in 10 healthy adolescents (mean age = 16.8, five females). Each subject completed a thermal exercise protocol and nonthermal exercise control condition in a cross-over repeated measures design. Subjects lost more weight via perspiration in the thermal exercise versus the control condition (P Dehydration following the thermal exercise protocol led to a significantly stronger increase in fronto-parietal blood-oxygen-level-dependent (BOLD) response during an executive function task (Tower of London) than the control condition, whereas cerebral perfusion during rest was not affected. The increase in BOLD response after dehydration was not paralleled by a change in cognitive performance, suggesting an inefficient use of brain metabolic activity following dehydration. This pattern indicates that participants exerted a higher level of neuronal activity in order to achieve the same performance level. Given the limited availability of brain metabolic resources, these findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visuo-spatial processing.

  3. Improved laser applicators for interstitial thermotherapy of brain structures

    Science.gov (United States)

    Schwarzmaier, Hans-Joachim; Goldbach, Thomas; Ulrich, Frank; Schober, Ralf; Kahn, Thomas; Kaufmann, Raimund; Wolbarsht, Myron L.

    1994-05-01

    Interstitial thermotherapy is a new treatment for deep seated brain tumors. To destroy large tissue volumes without adverse effects (vaporization, carbonization) a new laser catheter was developed. The device combines the radiative heating of distant tissue volumes with the conductive cooling of areas close to the optical fiber tip.

  4. Spontaneous Formation of Eutectic Crystal Structures in Binary and Ternary Charged Colloids due to Depletion Attraction

    Science.gov (United States)

    Toyotama, Akiko; Okuzono, Tohru; Yamanaka, Junpei

    2016-03-01

    Crystallization of colloids has extensively been studied for past few decades as models to study phase transition in general. Recently, complex crystal structures in multi-component colloids, including alloy and eutectic structures, have attracted considerable attention. However, the fabrication of 2D area-filling colloidal eutectics has not been reported till date. Here, we report formation of eutectic structures in binary and ternary aqueous colloids due to depletion attraction. We used charged particles + linear polyelectrolyte systems, in which the interparticle interaction could be represented as a sum of the electrostatic, depletion, and van der Waals forces. The interaction was tunable at a lengthscale accessible to direct observation by optical microscopy. The eutectic structures were formed because of interplay of crystallization of constituent components and accompanying fractionation. An observed binary phase diagram, defined by a mixing ratio and inverse area fraction of the particles, was analogous to that for atomic and molecular eutectic systems. This new method also allows the adjustment of both the number and wavelengths of Bragg diffraction peaks. Furthermore, these eutectic structures could be immobilized in polymer gel to produce self-standing materials. The present findings will be useful in the design of the optical properties of colloidal crystals.

  5. BRAIN ABSCESS DUE TO Staphylococcus aureus OF CRYPTOGENIC SOURCE IN AN HIV-1 INFECTED PATIENT IN USE OF ANTIRETROVIRAL THERAPY

    Science.gov (United States)

    de OLIVEIRA, Anna Paula Romero; PAPPALARDO, Mara Cristina; DANTAS, Daniel; LINS, Diogo; VIDAL, José Ernesto

    2016-01-01

    The spectrum of neurological complications associated with human immunodeficiency virus type 1 (HIV-1) infection is broad. The most frequent etiologies include primary diseases (caused by HIV itself) or secondary diseases (opportunistic infections or neoplasms). Despite these conditions, HIV-infected patients are susceptible to other infections observed in patients without HIV infection. Here we report a rare case of a brain abscess caused by Staphylococcus aureus in an HIV-infected patient. After drainage of the abscess and treatment with oxacilin, the patient had a favorable outcome. This case reinforces the importance of a timely neurosurgical procedure that supported adequate management of an unusual cause of expansive brain lesions in HIV-1 infected patients. PMID:27074328

  6. Hepatic but not brain iron is rapidly chelated by deferasirox in aceruloplasminemia due to a novel gene mutation

    OpenAIRE

    Finkenstedt, Armin; Wolf, Elisabeth; Höfner, Elmar; Gasser, Bethina Isasi; Bösch, Sylvia; Bakry, Rania; Creus, Marc; Kremser, Christian; Schocke, Michael; Theurl, Milan; Moser, Patrizia; Schranz, Melanie; Bonn, Guenther; Poewe, Werner; Vogel, Wolfgang

    2010-01-01

    Background & Aims Aceruloplasminemia is a rare autosomal recessive neurodegenerative disease associated with brain and liver iron accumulation which typically presents with movement disorders, retinal degeneration, and diabetes mellitus. Ceruloplasmin is a multi-copper ferroxidase that is secreted into plasma and facilitates cellular iron export and iron binding to transferrin. Results A novel homozygous ceruloplasmin gene mutation, c.2554+1G>T, was identified as the cause of aceruloplasminem...

  7. Nonparametric Bayesian Clustering of Structural Whole Brain Connectivity in Full Image Resolution

    DEFF Research Database (Denmark)

    Ambrosen, Karen Marie Sandø; Albers, Kristoffer Jon; Dyrby, Tim B.;

    2014-01-01

    groups) that defines structural units at the resolution of statistical support. We apply the model to a network of structural brain connectivity in full image resolution with more than one hundred thousand regions (voxels in the gray-white matter boundary) and around one hundred million connections......Diffusion magnetic resonance imaging enables measuring the structural connectivity of the human brain at a high spatial resolution. Local noisy connectivity estimates can be derived using tractography approaches and statistical models are necessary to quantify the brain’s salient structural....... The derived clustering identifies in the order of one thousand salient structural units and we find that the identified units provide better predictive performance than predicting using the full graph or two commonly used atlases. Extracting structural units of brain connectivity at the full image resolution...

  8. Association of structural global brain network properties with intelligence in normal aging.

    Directory of Open Access Journals (Sweden)

    Florian U Fischer

    Full Text Available Higher general intelligence attenuates age-associated cognitive decline and the risk of dementia. Thus, intelligence has been associated with cognitive reserve or resilience in normal aging. Neurophysiologically, intelligence is considered as a complex capacity that is dependent on a global cognitive network rather than isolated brain areas. An association of structural as well as functional brain network characteristics with intelligence has already been reported in young adults. We investigated the relationship between global structural brain network properties, general intelligence and age in a group of 43 cognitively healthy elderly, age 60-85 years. Individuals were assessed cross-sectionally using Wechsler Adult Intelligence Scale-Revised (WAIS-R and diffusion-tensor imaging. Structural brain networks were reconstructed individually using deterministic tractography, global network properties (global efficiency, mean shortest path length, and clustering coefficient were determined by graph theory and correlated to intelligence scores within both age groups. Network properties were significantly correlated to age, whereas no significant correlation to WAIS-R was observed. However, in a subgroup of 15 individuals aged 75 and above, the network properties were significantly correlated to WAIS-R. Our findings suggest that general intelligence and global properties of structural brain networks may not be generally associated in cognitively healthy elderly. However, we provide first evidence of an association between global structural brain network properties and general intelligence in advanced elderly. Intelligence might be affected by age-associated network deterioration only if a certain threshold of structural degeneration is exceeded. Thus, age-associated brain structural changes seem to be partially compensated by the network and the range of this compensation might be a surrogate of cognitive reserve or brain resilience.

  9. Brain structure and function in borderline personality disorder.

    Science.gov (United States)

    O'Neill, Aisling; Frodl, Thomas

    2012-10-01

    The spotlight on borderline personality disorder (BPD) has been growing in recent years, with the number of papers discussing potential causes and triggers of the disorder rapidly on the increase. Also on the increase, though still lacking sufficient numbers to produce well-supported hypotheses, are studies employing neuroimaging techniques as investigative tools in BPD. In this review, we investigate the current state and findings of neuroimaging studies in BPD, focusing in particular, on the studies examining structural, functional, and neurometabolic abnormalities in the disorder. Some suspected trends in the data are highlighted, including reductions in the hippocampi and amygdalae of BPD patients compared to healthy controls, exaggerated amygdala activity in BPD patients when confronted with emotion-related stimulus, and negative correlations between increases in left amygdalar creatine and reductions in amygdalar volume, reductions in absolute N-acetylaspartate concentration in the dorsolateral prefrontal cortex of BPD patients, and increases in glutamate concentration in the anterior cingulate cortices of BPD patients. We also discuss the limitations of some of the current studies including hindrances due to sample effects and techniques used and the potential of future neuroimaging research in BPD. PMID:22252376

  10. Structural Modifications in Fused Silica Due to Laser Damage Induced Shock Compression

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, A; Davila, L; Caturla, M J; Stolken, J S; Sadigh, B; Quong, A; Rubenchik, A; Feit, M D

    2001-12-05

    High power laser pulses can produce damage in high quality fused silica optics that can lead to its eventual obscuration and failure. Current models suggest the initiation of a plasma detonation due to absorbing initiators and defects, leading to the formation of shock waves. Recent experiments have found a densified layer at the bottom of damage sites, as evidence of the laser-damage model. We have studied the propagation of shock waves through fused silica using molecular dynamics. These simulations show drastic modifications in the structure and topology of the network, in agreement with experimental observations.

  11. A Simplified Method for Analyzing Truss Structure Due to Removal of Members

    Institute of Scientific and Technical Information of China (English)

    周岱; 周笠人; 刘红玉

    2003-01-01

    Based on relating equation group, a simplified method was presented in terms of the matrix displacement method, which can be conveniently used to study the re-distribution of the internal forces and displacement of truss structures due to the removal of members. Such removal is treated as though adding a load case to the original truss, and the re-distribution can be calculated without modifying the original global stiffness matrix. The computational efficiency of the presented method is faster by square times than that of the matrix displacement method.The results from the two methods are identical.

  12. Methods and considerations for longitudinal structural brain imaging analysis across development

    Directory of Open Access Journals (Sweden)

    Kathryn L. Mills

    2014-07-01

    Full Text Available Magnetic resonance imaging (MRI has allowed the unprecedented capability to measure the human brain in vivo. This technique has paved the way for longitudinal studies exploring brain changes across the entire life span. Results from these studies have given us a glimpse into the remarkably extended and multifaceted development of our brain, converging with evidence from anatomical and histological studies. Ever-evolving techniques and analytical methods provide new avenues to explore and questions to consider, requiring researchers to balance excitement with caution. This review addresses what MRI studies of structural brain development in children and adolescents typically measure and how. We focus on measurements of brain morphometry (e.g., volume, cortical thickness, surface area, folding patterns, as well as measurements derived from diffusion tensor imaging (DTI. By integrating finding from multiple longitudinal investigations, we give an update on current knowledge of structural brain development and how it relates to other aspects of biological development and possible underlying physiological mechanisms. Further, we review and discuss current strategies in image processing, analysis techniques and modeling of brain development. We hope this review will aid current and future longitudinal investigations of brain development, as well as evoke a discussion amongst researchers regarding best practices.

  13. Brain network analysis reveals affected connectome structure in bipolar I disorder.

    Science.gov (United States)

    Collin, Guusje; van den Heuvel, Martijn P; Abramovic, Lucija; Vreeker, Annabel; de Reus, Marcel A; van Haren, Neeltje E M; Boks, Marco P M; Ophoff, Roel A; Kahn, René S

    2016-01-01

    The notion that healthy brain function emerges from coordinated neural activity constrained by the brain's network of anatomical connections--i.e., the connectome--suggests that alterations in the connectome's wiring pattern may underlie brain disorders. Corroborating this hypothesis, studies in schizophrenia are indicative of altered connectome architecture including reduced communication efficiency, disruptions of central brain hubs, and affected "rich club" organization. Whether similar deficits are present in bipolar disorder is currently unknown. This study examines structural connectome topology in 216 bipolar I disorder patients as compared to 144 healthy controls, focusing in particular on central regions (i.e., brain hubs) and connections (i.e., rich club connections, interhemispheric connections) of the brain's network. We find that bipolar I disorder patients exhibit reduced global efficiency (-4.4%, P =0.002) and that this deficit relates (r = 0.56, P brain hub connections in general, or of connections spanning brain hubs (i.e., "rich club" connections) in particular (all P > 0.1). These findings highlight a role for aberrant brain network architecture in bipolar I disorder with reduced global efficiency in association with disruptions in interhemispheric connectivity, while the central "rich club" system appears not to be particularly affected.

  14. Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure

    Directory of Open Access Journals (Sweden)

    Taro Kakinuma

    2012-01-01

    Full Text Available Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.

  15. Structural brain abnormalities in early onset first-episode psychosis

    DEFF Research Database (Denmark)

    Pagsberg, A K; Baaré, W F C; Raabjerg Christensen, A M;

    2007-01-01

    BACKGROUND: Brain morphometry in children and adolescents with first-episode psychosis offer a unique opportunity for pathogenetic investigations. METHODS: We compared high-resolution 3D T1-weighted magnetic resonance images of the brain in 29 patients (schizophrenia, schizotypal disorder......, delusional disorder or other non-organic psychosis), aged 10-18 to those of 29 matched controls, using optimized voxel-based morphometry. RESULTS: Psychotic patients had frontal white matter abnormalities, but expected (regional) gray matter reductions were not observed. Post hoc analyses revealed...... already at illness onset in young schizophrenia spectrum patients, suggests aberrant neurodevelopmental processes in the pathogenesis of these disorders. Gray matter volume changes, however, appear not to be a key feature in early onset first-episode psychosis....

  16. Imaging Structural Plasticity Of Synapses In The Brain

    OpenAIRE

    Yu, Xinzhu

    2012-01-01

    Synapses are the sites where neurons contact each other and exchange information in the brain. Experience-dependent changes in synaptic connections are fundamental for numerous neurological processes, ranging from the development of neuronal circuitry to learning and memory. Dendritic spines are the postsynaptic sites of the majority of excitatory synapses in the mammalian central nervous system. The morphology and dynamics of dendritic spines change throughout the lifespan of animals, espe...

  17. Brain structural basis of cognitive reappraisal and expressive suppression

    OpenAIRE

    Hermann, Andrea; Bieber, Alexandra; Keck, Tanja; Vaitl, Dieter; Stark, Rudolf

    2013-01-01

    Cognitive reappraisal and expressive suppression, two major emotion regulation strategies, are differentially related to emotional well-being. The aim of this study was to test the association of individual differences in these two emotion regulation strategies with gray matter volume of brain regions that have been shown to be involved in the regulation of emotions. Based on high-resolution magnetic resonance images of 96 young adults voxel-based morphometry was used to analyze the gray matt...

  18. More bilateral, more anterior: Alterations of brain organization in the large-scale structural network in Chinese dyslexia.

    Science.gov (United States)

    Qi, Ting; Gu, Bin; Ding, Guosheng; Gong, Gaolang; Lu, Chunming; Peng, Danling; Malins, Jeff G; Liu, Li

    2016-01-01

    Abnormalities in large-scale brain networks have been recently reported in dyslexia; however, it remains unclear whether these abnormalities are congenital (due to dyslexia per se) or arise later in development. Here, structural magnetic resonance imaging data of 17 Chinese reading disabled (RD) and 17 age-matched typically developing (TD) children were used to construct cortical thickness (sensitive to postnatal development) and surface area (sensitive to prenatal development) networks. In the thickness network, compared to TD, RD showed reduced nodal network properties (e.g., degree and betweenness) in the left hemisphere along with enhanced nodal properties mainly in the right hemisphere. As for the surface area network, compared to TD, RD demonstrated lower nodal properties in the posterior brain regions and higher nodal properties in the anterior brain regions. Furthermore, hubs in both the thickness and surface area networks in RD were more distributed in frontal areas and less distributed in parietal areas, whereas TD showed the opposite pattern. Altogether, these findings indicate that the aberrant structural connectivity in the dyslexic individuals was not only due to a late developmental effect reflected in the altered thickness network, but may also be a congenital effect during prenatal development, reflected in the altered surface network.

  19. Insulin signaling disruption in male mice due to perinatal bisphenol A exposure: Role of insulin signaling in the brain.

    Science.gov (United States)

    Fang, Fangfang; Gao, Yue; Wang, Tingwei; Chen, Donglong; Liu, Jingli; Qian, Wenyi; Cheng, Jie; Gao, Rong; Wang, Jun; Xiao, Hang

    2016-03-14

    Bisphenol A (BPA), an environmental estrogenic endocrine disruptor, is widely used for producing polycarbonate plastics and epoxy resins. Available data have shown that perinatal exposure to BPA contributes to peripheral insulin resistance, while in the present study, we aimed to investigate the effects of perinatal BPA exposure on insulin signaling and glucose transport in the cortex of offspring mice. The pregnant mice were administrated either vehicle or BPA (100 μg/kg/day) at three perinatal stages. Stage I: from day 6 of gestation until parturition (P6-PND0 fetus exposure); Stage II: from lactation until delactation (PND0-PND21 newborn exposure) and Stage III: from day 6 of pregnancy until delactation (P6-PND21 fetus and newborn exposure). At 8 months of age for the offspring mice, the insulin signaling pathways and glucose transporters (GLUTs) were detected. Our data indicated that the insulin signaling including insulin, phosphorylated insulin receptor (IR), phosphorylated protein kinase B (p-AKT), phosphorylated glycogen synthase kinase 3β (p-GSK3β) and phosphorylated extracellular signal regulated protein kinase (p-ERK) were significantly decreased in the brain. In parallel, GLUTs (GLUT1/3/4) were obviously decreased as well in BPA-treated group in mice brain. Noteworthily, the phosphorylated tau (p-tau) and amyloid precursor protein (APP) were markedly up-regulated in all BPA-treated groups. These results, taken together, suggest the adverse effects of BPA on insulin signaling and GLUTs, which might subsequently contribute to the increment of p-tau and APP in the brain of adult offspring. Therefore, perinatal BPA exposure might be a risk factor for the long-term neurodegenerative changes in offspring male mice. PMID:26779933

  20. Insulin signaling disruption in male mice due to perinatal bisphenol A exposure: Role of insulin signaling in the brain.

    Science.gov (United States)

    Fang, Fangfang; Gao, Yue; Wang, Tingwei; Chen, Donglong; Liu, Jingli; Qian, Wenyi; Cheng, Jie; Gao, Rong; Wang, Jun; Xiao, Hang

    2016-03-14

    Bisphenol A (BPA), an environmental estrogenic endocrine disruptor, is widely used for producing polycarbonate plastics and epoxy resins. Available data have shown that perinatal exposure to BPA contributes to peripheral insulin resistance, while in the present study, we aimed to investigate the effects of perinatal BPA exposure on insulin signaling and glucose transport in the cortex of offspring mice. The pregnant mice were administrated either vehicle or BPA (100 μg/kg/day) at three perinatal stages. Stage I: from day 6 of gestation until parturition (P6-PND0 fetus exposure); Stage II: from lactation until delactation (PND0-PND21 newborn exposure) and Stage III: from day 6 of pregnancy until delactation (P6-PND21 fetus and newborn exposure). At 8 months of age for the offspring mice, the insulin signaling pathways and glucose transporters (GLUTs) were detected. Our data indicated that the insulin signaling including insulin, phosphorylated insulin receptor (IR), phosphorylated protein kinase B (p-AKT), phosphorylated glycogen synthase kinase 3β (p-GSK3β) and phosphorylated extracellular signal regulated protein kinase (p-ERK) were significantly decreased in the brain. In parallel, GLUTs (GLUT1/3/4) were obviously decreased as well in BPA-treated group in mice brain. Noteworthily, the phosphorylated tau (p-tau) and amyloid precursor protein (APP) were markedly up-regulated in all BPA-treated groups. These results, taken together, suggest the adverse effects of BPA on insulin signaling and GLUTs, which might subsequently contribute to the increment of p-tau and APP in the brain of adult offspring. Therefore, perinatal BPA exposure might be a risk factor for the long-term neurodegenerative changes in offspring male mice.

  1. Brain structure evolution in a basal vertebrate clade: evidence from phylogenetic comparative analysis of cichlid fishes

    Directory of Open Access Journals (Sweden)

    Kolm Niclas

    2009-09-01

    Full Text Available Abstract Background The vertebrate brain is composed of several interconnected, functionally distinct structures and much debate has surrounded the basic question of how these structures evolve. On the one hand, according to the 'mosaic evolution hypothesis', because of the elevated metabolic cost of brain tissue, selection is expected to target specific structures mediating the cognitive abilities which are being favored. On the other hand, the 'concerted evolution hypothesis' argues that developmental constraints limit such mosaic evolution and instead the size of the entire brain varies in response to selection on any of its constituent parts. To date, analyses of these hypotheses of brain evolution have been limited to mammals and birds; excluding Actinopterygii, the basal and most diverse class of vertebrates. Using a combination of recently developed phylogenetic multivariate allometry analyses and comparative methods that can identify distinct rates of evolution, even in highly correlated traits, we studied brain structure evolution in a highly variable clade of ray-finned fishes; the Tanganyikan cichlids. Results Total brain size explained 86% of the variance in brain structure volume in cichlids, a lower proportion than what has previously been reported for mammals. Brain structures showed variation in pair-wise allometry suggesting some degree of independence in evolutionary changes in size. This result is supported by variation among structures on the strength of their loadings on the principal size axis of the allometric analysis. The rate of evolution analyses generally supported the results of the multivariate allometry analyses, showing variation among several structures in their evolutionary patterns. The olfactory bulbs and hypothalamus were found to evolve faster than other structures while the dorsal medulla presented the slowest evolutionary rate. Conclusion Our results favor a mosaic model of brain evolution, as certain

  2. Characterization of hydrofoil damping due to fluid-structure interaction using piezocomposite actuators

    Science.gov (United States)

    Seeley, Charles; Coutu, André; Monette, Christine; Nennemann, Bernd; Marmont, Hugues

    2012-03-01

    Hydroelectric power generation is an important non-fossil fuel power source to help meet the world’s energy needs. Fluid-structure interaction (FSI), in the form of mass loading and damping, governs the dynamic response of water turbines, such as Francis turbines. Although the effects of fluid mass loading are well documented, fluid damping is also a critical quantity that may limit vibration amplitudes during service, and therefore help to avoid premature failure of the turbines. However, fluid damping has received less attention in the literature. This paper presents an experimental investigation of damping due to FSI. Three hydrofoils were designed and built to investigate damping due to FSI. Piezoelectric actuation using macrofiber composites (MFCs) provided excitation to the hydrofoil test structure, independent of the flow conditions, to overcome the noisy environment. Natural frequency and damping estimates were experimentally obtained from sine sweep frequency response functions measured with a laser vibrometer through a window in the test section. The results indicate that, although the natural frequencies were not substantially affected by the flow, the damping ratios were observed to increase in a linear manner with respect to flow velocity.

  3. Targeting of deep-brain structures in nonhuman primates using MR and CT Images

    Science.gov (United States)

    Chen, Antong; Hines, Catherine; Dogdas, Belma; Bone, Ashleigh; Lodge, Kenneth; O'Malley, Stacey; Connolly, Brett; Winkelmann, Christopher T.; Bagchi, Ansuman; Lubbers, Laura S.; Uslaner, Jason M.; Johnson, Colena; Renger, John; Zariwala, Hatim A.

    2015-03-01

    In vivo gene delivery in central nervous systems of nonhuman primates (NHP) is an important approach for gene therapy and animal model development of human disease. To achieve a more accurate delivery of genetic probes, precise stereotactic targeting of brain structures is required. However, even with assistance from multi-modality 3D imaging techniques (e.g. MR and CT), the precision of targeting is often challenging due to difficulties in identification of deep brain structures, e.g. the striatum which consists of multiple substructures, and the nucleus basalis of meynert (NBM), which often lack clear boundaries to supporting anatomical landmarks. Here we demonstrate a 3D-image-based intracranial stereotactic approach applied toward reproducible intracranial targeting of bilateral NBM and striatum of rhesus. For the targeting we discuss the feasibility of an atlas-based automatic approach. Delineated originally on a high resolution 3D histology-MR atlas set, the NBM and the striatum could be located on the MR image of a rhesus subject through affine and nonrigid registrations. The atlas-based targeting of NBM was compared with the targeting conducted manually by an experienced neuroscientist. Based on the targeting, the trajectories and entry points for delivering the genetic probes to the targets could be established on the CT images of the subject after rigid registration. The accuracy of the targeting was assessed quantitatively by comparison between NBM locations obtained automatically and manually, and finally demonstrated qualitatively via post mortem analysis of slices that had been labelled via Evan Blue infusion and immunohistochemistry.

  4. Age-related changes of normal adult brain structure: analysed with diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yun-ting; ZHANG Chun-yan; ZHANG Jing; LI Wei

    2005-01-01

    Background It is known that the brain structure changes with normal aging. The objective of this study was to quantify the anisotropy and average diffusion coefficient (DCavg) of the brain in normal adults to demonstrate the microstructure changes of brain with aging.Methods One hundred and six normal adults were examined with diffusion tensor imaging (DTI). The fractional anisotropy (FA), 1-volume ratio (1-VR), relative anisotropy (RA) and average diffusion coefficient (DCavg) of different anatomic sites of brain were measured, correlated with age and compared among three broad age groups.Results Except in lentiform nucleus, the anisotropy increased and DCavg decreased with aging. Both anisotropy and DCavg of lentiform nucleus increased with aging. The normal reference values of DTI parameters of normal Chinese adult in major anatomic sites were acquired. Conclusions DTI data obtained noninvasively can reflect the microstructural changes with aging. The normal reference values acquired can serve as reference standards in differentiation of brain white matter diseases.

  5. Local appearance features for robust MRI brain structure segmentation across scanning protocols

    DEFF Research Database (Denmark)

    Achterberg, H.C.; Poot, D.H.J.; Van Der Lijn, F.;

    2013-01-01

    Segmentation of brain structures in magnetic resonance images is an important task in neuro image analysis. Several papers on this topic have shown the benefit of supervised classification based on local appearance features, often combined with atlas-based approaches. These methods require a...... representative annotated training set and therefore often do not perform well if the target image is acquired on a different scanner or with a different acquisition protocol than the training images. Assuming that the appearance of the brain is determined by the underlying brain tissue distribution and that...... brain tissue classification can be performed robustly for images obtained with different protocols, we propose to derive appearance features from brain-tissue density maps instead of directly from the MR images. We evaluated this approach on hippocampus segmentation in two sets of images acquired with...

  6. Automated delineation of brain structures in patients undergoing radiotherapy for primary brain tumors: From atlas to dose–volume histograms

    International Nuclear Information System (INIS)

    Purpose: To implement and evaluate a magnetic resonance imaging atlas-based automated segmentation (MRI-ABAS) procedure for cortical and sub-cortical grey matter areas definition, suitable for dose-distribution analyses in brain tumor patients undergoing radiotherapy (RT). Patients and methods: 3T-MRI scans performed before RT in ten brain tumor patients were used. The MRI-ABAS procedure consists of grey matter classification and atlas-based regions of interest definition. The Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm was applied to structures manually delineated by four experts to generate the standard reference. Performance was assessed comparing multiple geometrical metrics (including Dice Similarity Coefficient – DSC). Dosimetric parameters from dose–volume-histograms were also generated and compared. Results: Compared with manual delineation, MRI-ABAS showed excellent reproducibility [median DSCABAS = 1 (95% CI, 0.97–1.0) vs. DSCMANUAL = 0.90 (0.73–0.98)], acceptable accuracy [DSCABAS = 0.81 (0.68–0.94) vs. DSCMANUAL = 0.90 (0.76–0.98)], and an overall 90% reduction in delineation time. Dosimetric parameters obtained using MRI-ABAS were comparable with those obtained by manual contouring. Conclusions: The speed, reproducibility, and robustness of the process make MRI-ABAS a valuable tool for investigating radiation dose–volume effects in non-target brain structures providing additional standardized data without additional time-consuming procedures

  7. A longitudinal study of structural brain network changes with normal aging

    Directory of Open Access Journals (Sweden)

    Kai eWu

    2013-04-01

    Full Text Available The aim of this study was to investigate age-related changes in the topological organization of structural brain networks by applying a longitudinal design over 6 years. Structural brain networks were derived from measurements of regional gray matter volume and were constructed in age-specific groups from baseline and follow-up scans. The structural brain networks showed economical small-world properties, providing high global and local efficiency for parallel information processing at low connection costs. In the analysis of the global network properties, the local and global efficiency of the baseline scan were significantly lower compared to the follow-up scan. Moreover, the annual rate of changes in local and global efficiency showed a positive and negative quadratic correlation with the baseline age, respectively; both curvilinear correlations peaked at approximately the age of 50. In the analysis of the regional nodal properties, significant negative correlations between the annual rate of changes in nodal strength and the baseline age were found in the brain regions primarily involved in the visual and motor/ control systems, whereas significant positive quadratic correlations were found in the brain regions predominately associated with the default-mode, attention, and memory systems. The results of the longitudinal study are consistent with the findings of our previous cross-sectional study: the structural brain networks develop into a fast distribution from young to middle age (approximately 50 years old and eventually became a fast localization in the old age. Our findings elucidate the network topology of structural brain networks and its longitudinal changes, thus enhancing the understanding of the underlying physiology of normal aging in the human brain.

  8. 3D printing of layered brain-like structures using peptide modified gellan gum substrates.

    Science.gov (United States)

    Lozano, Rodrigo; Stevens, Leo; Thompson, Brianna C; Gilmore, Kerry J; Gorkin, Robert; Stewart, Elise M; in het Panhuis, Marc; Romero-Ortega, Mario; Wallace, Gordon G

    2015-10-01

    The brain is an enormously complex organ structured into various regions of layered tissue. Researchers have attempted to study the brain by modeling the architecture using two dimensional (2D) in vitro cell culturing methods. While those platforms attempt to mimic the in vivo environment, they do not truly resemble the three dimensional (3D) microstructure of neuronal tissues. Development of an accurate in vitro model of the brain remains a significant obstacle to our understanding of the functioning of the brain at the tissue or organ level. To address these obstacles, we demonstrate a new method to bioprint 3D brain-like structures consisting of discrete layers of primary neural cells encapsulated in hydrogels. Brain-like structures were constructed using a bio-ink consisting of a novel peptide-modified biopolymer, gellan gum-RGD (RGD-GG), combined with primary cortical neurons. The ink was optimized for a modified reactive printing process and developed for use in traditional cell culturing facilities without the need for extensive bioprinting equipment. Furthermore the peptide modification of the gellan gum hydrogel was found to have a profound positive effect on primary cell proliferation and network formation. The neural cell viability combined with the support of neural network formation demonstrated the cell supportive nature of the matrix. The facile ability to form discrete cell-containing layers validates the application of this novel printing technique to form complex, layered and viable 3D cell structures. These brain-like structures offer the opportunity to reproduce more accurate 3D in vitro microstructures with applications ranging from cell behavior studies to improving our understanding of brain injuries and neurodegenerative diseases.

  9. MRI as a tool to study brain structure from mouse models for mental retardation

    Science.gov (United States)

    Verhoye, Marleen; Sijbers, Jan; Kooy, R. F.; Reyniers, E.; Fransen, E.; Oostra, B. A.; Willems, Peter; Van der Linden, Anne-Marie

    1998-07-01

    Nowadays, transgenic mice are a common tool to study brain abnormalities in neurological disorders. These studies usually rely on neuropathological examinations, which have a number of drawbacks, including the risk of artefacts introduced by fixation and dehydration procedures. Here we present 3D Fast Spin Echo Magnetic Resonance Imaging (MRI) in combination with 2D and 3D segmentation techniques as a powerful tool to study brain anatomy. We set up MRI of the brain in mouse models for the fragile X syndrome (FMR1 knockout) and Corpus callosum hypoplasia, mental Retardation, Adducted thumbs, Spastic paraplegia and Hydrocephalus (CRASH) syndrome (L1CAM knockout). Our major goal was to determine qualitative and quantitative differences in specific brain structures. MRI of the brain of fragile X and CRASH patients has revealed alterations in the size of specific brain structures, including the cerebellar vermis and the ventricular system. In the present MRI study of the brain from fragile X knockout mice, we have measured the size of the brain, cerebellum and 4th ventricle, which were reported as abnormal in human fragile X patients, but found no evidence for altered brain regions in the mouse model. In CRASH syndrome, the most specific brain abnormalities are vermis hypoplasia and abnormalities of the ventricular system with some degree of hydrocephalus. With the MRI study of L1CAM knockout mice we found vermis hypoplasia, abnormalities of the ventricular system including dilatation of the lateral and the 4th ventricles. These subtle abnormalities were not detected upon standard neuropathological examination. Here we proved that this sensitive MRI technique allows to measure small differences which can not always be detected by means of pathology.

  10. Genetic and Environmental Contributions to the Relationships between Brain Structure and Average Lifetime Cigarette Use

    Science.gov (United States)

    Prom-Wormley, Elizabeth; Maes, Hermine H.M.; Schmitt, J. Eric; Panizzon, Matthew S.; Xian, Hong; Eyler, Lisa T.; Franz, Carol E.; Lyons, Michael J.; Tsuang, Ming T.; Dale, Anders M.; Fennema-Notestine, Christine; Kremen, William S.; Neale, Michael C.

    2015-01-01

    Chronic cigarette use has been consistently associated with differences in the neuroanatomy of smokers relative to nonsmokers in case-control studies. However, the etiology underlying the relationships between brain structure and cigarette use is unclear. A community-based sample of male twin pairs ages 51-59 (110 monozygotic pairs, 92 dizygotic pairs) was used to determine the extent to which there are common genetic and environmental influences between brain structure and average lifetime cigarette use. Brain structure was measured by high-resolution structural magnetic resonance imaging, from which subcortical volume and cortical volume, thickness and surface area were derived. Bivariate genetic models were fitted between these measures and average lifetime cigarette use measured as cigarette pack-years. Widespread, negative phenotypic correlations were detected between cigarette pack-years and several cortical as well as subcortical structures. Shared genetic and unique environmental factors contributed to the phenotypic correlations shared between cigarette pack-years and subcortical volume as well as cortical volume and surface area. Brain structures involved in many of the correlations were previously reported to play a role in specific aspects of networks of smoking-related behaviors. These results provide evidence for conducting future research on the etiology of smoking-related behaviors using measures of brain morphology. PMID:25690561

  11. Structural brain plasticity induced by physical training in adults affected by aging or disease related impairments: a systematic review

    OpenAIRE

    Van Oosterwijck, Jessica; Dhondt, Evy; Caeyenberghs, Karen; Burggraeve, Lieselot; Danneels, Lieven

    2015-01-01

    Background: Structural brain plasticity is observed as a consequence of alterations in input/behavior or of disease. For instance aging is associated with structural decline of the brain, and structural brain alterations have been identified in certain medical pathologies. While physical exercise has a positive impact on function, health status and quality of life in those affected by disease or neurodegenerative related deteriorations, the question remains if structural plasticity of the bra...

  12. Structural and functional rejuvenation of the aged brain by an approved anti-asthmatic drug

    OpenAIRE

    Marschallinger, J.; I. Schäffner; B. Klein(Ghent University, Ghent, Belgium); R. Gelfert; F.J. Rivera; S. Illes; L. Grassner; Janssen, M.; P. Rotheneichner; C. Schmuckermair; R. Coras; M. Boccazzi; M. Chishty; F.B. Lagler; M. Renic

    2015-01-01

    As human life expectancy has improved rapidly in industrialized societies, age-related cognitive impairment presents an increasing challenge. Targeting histopathological processes that correlate with age-related cognitive declines, such as neuroinflammation, low levels of neurogenesis, disrupted blood–brain barrier and altered neuronal activity, might lead to structural and functional rejuvenation of the aged brain. Here we show that a 6-week treatment of young (4 months) and old (20 months) ...

  13. Investigating Structural Brain Changes of Dehydration Using Voxel-Based Morphometry

    OpenAIRE

    Streitbürger, Daniel-Paolo; Möller, Harald E.; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Matthias L Schroeter; Mueller, Karsten

    2012-01-01

    Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T 1-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (V...

  14. A Multimodal Approach for Determining Brain Networks by Jointly Modeling Functional and Structural Connectivity

    Directory of Open Access Journals (Sweden)

    Wenqiong eXue

    2015-02-01

    Full Text Available Recent innovations in neuroimaging technology have provided opportunities for researchers to investigate connectivity in the human brain by examining the anatomical circuitry as well as functional relationships between brain regions. Existing statistical approaches for connectivity generally examine resting-state or task-related functional connectivity (FC between brain regions or separately examine structural linkages. As a means to determine brain networks, we present a unified Bayesian framework for analyzing FC utilizing the knowledge of associated structural connections, which extends an approach by Patel et al.(2006a that considers only functional data. We introduce an FC measure that rests upon assessments of functional coherence between regional brain activity identified from functional magnetic resonance imaging (fMRI data. Our structural connectivity (SC information is drawn from diffusion tensor imaging (DTI data, which is used to quantify probabilities of SC between brain regions. We formulate a prior distribution for FC that depends upon the probability of SC between brain regions, with this dependence adhering to structural-functional links revealed by our fMRI and DTI data. We further characterize the functional hierarchy of functionally connected brain regions by defining an ascendancy measure that compares the marginal probabilities of elevated activity between regions. In addition, we describe topological properties of the network, which is composed of connected region pairs, by performing graph theoretic analyses. We demonstrate the use of our Bayesian model using fMRI and DTI data from a study of auditory processing. We further illustrate the advantages of our method by comparisons to methods that only incorporate functional information.

  15. Structural brain network analysis in families multiply affected with bipolar I disorder

    NARCIS (Netherlands)

    Forde, Natalie J.; O'Donoghue, Stefani; Scanlon, Cathy; Emsell, Louise; Chaddock, Chris; Leemans, Alexander; Jeurissen, Ben; Barker, Gareth J.; Cannon, Dara M.; Murray, Robin M.; McDonald, Colm

    2015-01-01

    Disrupted structural connectivity is associated with psychiatric illnesses including bipolar disorder (BP). Here we use structural brain network analysis to investigate connectivity abnormalities in multiply affected BP type I families, to assess the utility of dysconnectivity as a biomarker and its

  16. Brain Structural Correlates of Emotion Recognition in Psychopaths.

    Science.gov (United States)

    Pera-Guardiola, Vanessa; Contreras-Rodríguez, Oren; Batalla, Iolanda; Kosson, David; Menchón, José M; Pifarré, Josep; Bosque, Javier; Cardoner, Narcís; Soriano-Mas, Carles

    2016-01-01

    Individuals with psychopathy present deficits in the recognition of facial emotional expressions. However, the nature and extent of these alterations are not fully understood. Furthermore, available data on the functional neural correlates of emotional face recognition deficits in adult psychopaths have provided mixed results. In this context, emotional face morphing tasks may be suitable for clarifying mild and emotion-specific impairments in psychopaths. Likewise, studies exploring corresponding anatomical correlates may be useful for disentangling available neurofunctional evidence based on the alleged neurodevelopmental roots of psychopathic traits. We used Voxel-Based Morphometry and a morphed emotional face expression recognition task to evaluate the relationship between regional gray matter (GM) volumes and facial emotion recognition deficits in male psychopaths. In comparison to male healthy controls, psychopaths showed deficits in the recognition of sad, happy and fear emotional expressions. In subsequent brain imaging analyses psychopaths with better recognition of facial emotional expressions showed higher volume in the prefrontal cortex (orbitofrontal, inferior frontal and dorsomedial prefrontal cortices), somatosensory cortex, anterior insula, cingulate cortex and the posterior lobe of the cerebellum. Amygdala and temporal lobe volumes contributed to better emotional face recognition in controls only. These findings provide evidence suggesting that variability in brain morphometry plays a role in accounting for psychopaths' impaired ability to recognize emotional face expressions, and may have implications for comprehensively characterizing the empathy and social cognition dysfunctions typically observed in this population of subjects. PMID:27175777

  17. Brain Structural Correlates of Emotion Recognition in Psychopaths

    Science.gov (United States)

    Batalla, Iolanda; Kosson, David; Menchón, José M; Pifarré, Josep; Bosque, Javier; Cardoner, Narcís; Soriano-Mas, Carles

    2016-01-01

    Individuals with psychopathy present deficits in the recognition of facial emotional expressions. However, the nature and extent of these alterations are not fully understood. Furthermore, available data on the functional neural correlates of emotional face recognition deficits in adult psychopaths have provided mixed results. In this context, emotional face morphing tasks may be suitable for clarifying mild and emotion-specific impairments in psychopaths. Likewise, studies exploring corresponding anatomical correlates may be useful for disentangling available neurofunctional evidence based on the alleged neurodevelopmental roots of psychopathic traits. We used Voxel-Based Morphometry and a morphed emotional face expression recognition task to evaluate the relationship between regional gray matter (GM) volumes and facial emotion recognition deficits in male psychopaths. In comparison to male healthy controls, psychopaths showed deficits in the recognition of sad, happy and fear emotional expressions. In subsequent brain imaging analyses psychopaths with better recognition of facial emotional expressions showed higher volume in the prefrontal cortex (orbitofrontal, inferior frontal and dorsomedial prefrontal cortices), somatosensory cortex, anterior insula, cingulate cortex and the posterior lobe of the cerebellum. Amygdala and temporal lobe volumes contributed to better emotional face recognition in controls only. These findings provide evidence suggesting that variability in brain morphometry plays a role in accounting for psychopaths’ impaired ability to recognize emotional face expressions, and may have implications for comprehensively characterizing the empathy and social cognition dysfunctions typically observed in this population of subjects. PMID:27175777

  18. Brain Structural Correlates of Emotion Recognition in Psychopaths.

    Directory of Open Access Journals (Sweden)

    Vanessa Pera-Guardiola

    Full Text Available Individuals with psychopathy present deficits in the recognition of facial emotional expressions. However, the nature and extent of these alterations are not fully understood. Furthermore, available data on the functional neural correlates of emotional face recognition deficits in adult psychopaths have provided mixed results. In this context, emotional face morphing tasks may be suitable for clarifying mild and emotion-specific impairments in psychopaths. Likewise, studies exploring corresponding anatomical correlates may be useful for disentangling available neurofunctional evidence based on the alleged neurodevelopmental roots of psychopathic traits. We used Voxel-Based Morphometry and a morphed emotional face expression recognition task to evaluate the relationship between regional gray matter (GM volumes and facial emotion recognition deficits in male psychopaths. In comparison to male healthy controls, psychopaths showed deficits in the recognition of sad, happy and fear emotional expressions. In subsequent brain imaging analyses psychopaths with better recognition of facial emotional expressions showed higher volume in the prefrontal cortex (orbitofrontal, inferior frontal and dorsomedial prefrontal cortices, somatosensory cortex, anterior insula, cingulate cortex and the posterior lobe of the cerebellum. Amygdala and temporal lobe volumes contributed to better emotional face recognition in controls only. These findings provide evidence suggesting that variability in brain morphometry plays a role in accounting for psychopaths' impaired ability to recognize emotional face expressions, and may have implications for comprehensively characterizing the empathy and social cognition dysfunctions typically observed in this population of subjects.

  19. Unraveling the multiscale structural organization and connectivity of the human brain: the role of diffusion MRI

    Directory of Open Access Journals (Sweden)

    Matteo eBastiani

    2015-06-01

    Full Text Available The structural architecture and the anatomical connectivity of the human brain show different organizational principles at distinct spatial scales. Histological staining and light microscopy techniques have been widely used in classical neuroanatomical studies to unravel brain organization. Using such techniques is a laborious task performed on 2-dimensional histological sections by skilled anatomists possibly aided by semi-automated algorithms. With the recent advent of modern magnetic resonance imaging (MRI contrast mechanisms, cortical layers and columns can now be reliably identified and their structural properties quantified post mortem. These developments are allowing the investigation of neuroanatomical features of the brain at a spatial resolution that could be interfaced with that of histology. Diffusion MRI and tractography techniques, in particular, have been used to probe the architecture of both white and gray matter in three dimensions. Combined with mathematical network analysis, these techniques are increasingly influential in the investigation of the macro-, meso- and microscopic organization of brain connectivity and anatomy, both in vivo and ex vivo. Diffusion MRI-based techniques in combination with histology approaches can therefore support the endeavor of creating multimodal atlases that take into account the different spatial scales or levels on which the brain is organized. The aim of this review is to illustrate and discuss the structural architecture and the anatomical connectivity of the human brain at different spatial scales and how recently developed diffusion MRI techniques can help investigate these.

  20. Brain structure variation in great apes, with attention to the mountain gorilla (Gorilla beringei beringei).

    Science.gov (United States)

    Sherwood, Chet C; Cranfield, Michael R; Mehlman, Patrick T; Lilly, Alecia A; Garbe, Jo Anne L; Whittier, Christopher A; Nutter, Felicia B; Rein, Thomas R; Bruner, Harlan J; Holloway, Ralph L; Tang, Cheuk Y; Naidich, Thomas P; Delman, Bradley N; Steklis, H Dieter; Erwin, Joseph M; Hof, Patrick R

    2004-07-01

    This report presents data regarding the brain structure of mountain gorillas (Gorilla beringei beringei) in comparison with other great apes. Magnetic resonance (MR) images of three mountain gorilla brains were obtained with a 3T scanner, and the volume of major neuroanatomical structures (neocortical gray matter, hippocampus, thalamus, striatum, and cerebellum) was measured. These data were included with our existing database that includes 23 chimpanzees, three western lowland gorillas, and six orangutans. We defined a multidimensional space by calculating the principal components (PCs) from the correlation matrix of brain structure fractions in the well-represented sample of chimpanzees. We then plotted data from all of the taxa in this space to examine phyletic variation in neural organization. Most of the variance in mountain gorillas, as well as other great apes, was contained within the chimpanzee range along the first two PCs, which accounted for 61.73% of the total variance. Thus, the majority of interspecific variation in brain structure observed among these ape taxa was no greater than the within-species variation seen in chimpanzees. The loadings on PCs indicated that the brain structure of great apes differs among taxa mostly in the relative sizes of the striatum, cerebellum, and hippocampus. These findings suggest possible functional differences among taxa in terms of neural adaptations for ecological and locomotor capacities. Importantly, these results fill a critical gap in current knowledge regarding great ape neuroanatomical diversity. PMID:15258959

  1. Uncertainty in Earthquake Source Imaging Due to Variations in Source Time Function and Earth Structure

    KAUST Repository

    Razafindrakoto, H. N. T.

    2014-03-25

    One way to improve the accuracy and reliability of kinematic earthquake source imaging is to investigate the origin of uncertainty and to minimize their effects. The difficulties in kinematic source inversion arise from the nonlinearity of the problem, nonunique choices in the parameterization, and observational errors. We analyze particularly the uncertainty related to the choice of the source time function (STF) and the variability in Earth structure. We consider a synthetic data set generated from a spontaneous dynamic rupture calculation. Using Bayesian inference, we map the solution space of peak slip rate, rupture time, and rise time to characterize the kinematic rupture in terms of posterior density functions. Our test to investigate the effect of the choice of STF reveals that all three tested STFs (isosceles triangle, regularized Yoffe with acceleration time of 0.1 and 0.3 s) retrieve the patch of high slip and slip rate around the hypocenter. However, the use of an isosceles triangle as STF artificially accelerates the rupture to propagate faster than the target solution. It additionally generates an artificial linear correlation between rupture onset time and rise time. These appear to compensate for the dynamic source effects that are not included in the symmetric triangular STF. The exact rise time for the tested STFs is difficult to resolve due to the small amount of radiated seismic moment in the tail of STF. To highlight the effect of Earth structure variability, we perform inversions including the uncertainty in the wavespeed only, and variability in both wavespeed and layer depth. We find that little difference is noticeable between the resulting rupture model uncertainties from these two parameterizations. Both significantly broaden the posterior densities and cause faster rupture propagation particularly near the hypocenter due to the major velocity change at the depth where the fault is located.

  2. Individual differences in brain structure and resting brain function underlie cognitive styles: evidence from the Embedded Figures Test.

    Directory of Open Access Journals (Sweden)

    Xin Hao

    Full Text Available Cognitive styles can be characterized as individual differences in the way people perceive, think, solve problems, learn, and relate to others. Field dependence/independence (FDI is an important and widely studied dimension of cognitive styles. Although functional imaging studies have investigated the brain activation of FDI cognitive styles, the combined structural and functional correlates with individual differences in a large sample have never been investigated. In the present study, we investigated the neural correlates of individual differences in FDI cognitive styles by analyzing the correlations between Embedded Figures Test (EFT score and structural neuroimaging data [regional gray matter volume (rGMV was assessed using voxel-based morphometry (VBM]/functional neuroimaging data [resting-brain functions were measured by amplitude of low-frequency fluctuation (ALFF] throughout the whole brain. Results showed that the increased rGMV in the left inferior parietal lobule (IPL was associated with the EFT score, which might be the structural basis of effective local processing. Additionally, a significant positive correlation between ALFF and EFT score was found in the fronto-parietal network, including the left inferior parietal lobule (IPL and the medial prefrontal cortex (mPFC. We speculated that the left IPL might be associated with superior feature identification, and mPFC might be related to cognitive inhibition of global processing bias. These results suggested that the underlying neuroanatomical and functional bases were linked to the individual differences in FDI cognitive styles and emphasized the important contribution of superior local processing ability and cognitive inhibition to field-independent style.

  3. Active load path adaption in a simple kinematic load-bearing structure due to stiffness change in the structure's supports

    Science.gov (United States)

    Gehb, C. M.; Platz, R.; Melz, T.

    2016-09-01

    Load-bearing structures with kinematic functions enable and disable degrees of freedom and are part of many mechanical engineering applications. The relative movement between a wheel and the body of a car or a landing gear and an aircraft fuselage are examples for load-bearing systems with defined kinematics. In most cases, the load is transmitted through a predetermined load path to the structural support interfaces. However, unexpected load peaks or varying health condition of the system's supports, which means for example varying damping and stiffness characteristics, may require an active adjustment of the load path. However, load paths transmitted through damaged or weakened supports can be the reason for reduced comfort or even failure. In this paper a simplified 2D two mass oscillator with two supports is used to numerically investigate the potential of controlled adaptive auxiliary kinematic guidance elements in a load-bearing structure to adapt the load path depending on the stiffness change, representing damage of the supports. The aim is to provide additional forces in the auxiliary kinematic guidance elements for two reasons. On the one hand, one of the two supports that may become weaker through stiffness change will be relieved from higher loading. On the other hand, tilting due to different compliance in the supports will be minimized. Therefore, shifting load between the supports during operation could be an effective option.

  4. Structural brain imaging in children and adolescents following prenatal cocaine exposure: preliminary longitudinal findings.

    Science.gov (United States)

    Akyuz, Nurunisa; Kekatpure, Minal V; Liu, Jie; Sheinkopf, Stephen J; Quinn, Brian T; Lala, Meenakshi D; Kennedy, David; Makris, Nikos; Lester, Barry M; Kosofsky, Barry E

    2014-01-01

    The brain morphometry of 21 children, who were followed from birth and underwent structural brain magnetic resonance imaging at 8-10 years, was studied. This cohort included 11 children with prenatal cocaine exposure (CE) and 10 noncocaine-exposed children (NCE). We compared the CE versus NCE groups using FreeSurfer to automatically segment and quantify the volume of individual brain structures. In addition, we created a pediatric atlas specifically for this population and demonstrate the enhanced accuracy of this approach. We found an overall trend towards smaller brain volumes among CE children. The volume differences were significant for cortical gray matter, the thalamus and the putamen. Here, reductions in thalamic and putaminal volumes showed a robust inverse correlation with exposure levels, thus highlighting effects on dopamine-rich brain regions that form key components of brain circuitry known to play important roles in behavior and attention. Interestingly, head circumferences (HCs) at birth as well as at the time of imaging showed a tendency for smaller size among CE children. HCs at the time of imaging correlated well with the cortical volumes for all subjects. In contrast, HCs at birth were predictive of the cortical volume only for the CE group. A subgroup of these subjects (6 CE, 4 NCE) was also scanned at 13-15 years of age. In subjects who were scanned twice, we found that the trend for smaller structures continued into teenage years. We found that the differences in structural volumes between the CE and NCE groups are largely diminished when the HCs are controlled for or matched by study design. Participants in this study were drawn from a unique longitudinal cohort and, while the small sample size precludes strong conclusions regarding the longitudinal findings reported, the results point to reductions in HCs and in specific brain structures that persist through teenage years in children who were exposed to cocaine in utero. PMID:24994509

  5. Structural Brain Imaging in Children and Adolescents Following Prenatal Cocaine Exposure

    Science.gov (United States)

    Akyuz, Nurunisa; Kekatpure, Minal V.; Liu, Jie; Sheinkopf, Stephen J.; Quinn, Brian T.; Lala, Meenakshi D.; Kennedy, David; Makris, Nikos; Lester, Barry M.; Kosofsky, Barry E.

    2014-01-01

    Brain morphometry of 21 children, who were followed from birth and underwent structural brain magnetic resonance imaging (MRI) at 8–10 years, were studied. This cohort included 11 children with prenatal cocaine exposure (CE) and 10 non-cocaine exposed children (NCE). We compared the CE versus NCE groups using FreeSurfer to automatically segment and quantify the volume of individual brain structures. In addition, we created a pediatric atlas specifically for this population and demonstrate the enhanced accuracy of this approach. We found an overall trend towards smaller brain volumes among CE children. The volume differences were significant for cortical gray matter, thalamus and putamen. Here, reductions in thalamic and putaminal volumes showed a robust inverse-correlation with exposure levels, thus highlighting effects on dopamine rich brain regions that form key components of brain circuitry known to play important roles in behavior and attention. Interestingly, head circumferences (HCs) at birth as well as at the time of imaging showed a tendency for smaller size among CE children. HCs at the time of imaging correlated well with the cortical volumes, for all subjects. In contrast, HCs at birth were predictive of the cortical volume only for the CE group. A subgroup of these subjects (6 CE and 4 NCE) was also scanned at 13–15 years old. In subjects who were scanned twice, we found that the trend for smaller structures continues into 13–15 years of age. We found that the differences in structural volumes between CE and NCE groups are largely diminished when the HCs are matched by study design or controlled for. Participants in this study were drawn from a unique longitudinal cohort, and while the small sample size precludes strong conclusions, the results point to reductions in HCs and in specific brain structures that persist through teenage years in children who were exposed to cocaine in utero. PMID:24994509

  6. Brain Basics

    Medline Plus

    Full Text Available ... Basics will introduce you to some of this science, such as: How the brain develops How genes and the environment affect the brain The basic structure of the brain How different parts of ...

  7. Fractal flame structure due to the hydrodynamic Darrieus-Landau instability

    Science.gov (United States)

    Yu, Rixin; Bai, Xue-Song; Bychkov, Vitaly

    2015-12-01

    By using large scale numerical simulations, we obtain fractal structure, which develops at originally planar flame fronts due to the hydrodynamic Darrieus-Landau (DL) instability bending the fronts. We clarify some important issues regarding the DL fractal flames, which have been debated for a long time. We demonstrate an increase of the flame propagation speed with the hypothetic channel width, which controls the length scale of the instability development. We show that this increase may be fitted by a power law indicating the mean fractal properties of the flame front structure. The power exponent in this law is found to be not a universal constant, rather it depends on the flame properties—on the density drop at the front. Using box counting on the simulated flame front shapes we show the fractal flame dimension at the intermediate scale is smaller than the one given by the power law, but it has a similar dependency on the density drop. We also obtain a formation of pockets at the DL fractal flame fronts, which previously has been associated only with turbulent burning.

  8. The Energy-Dependent Position of the IBEX Ribbon Due to the Solar Wind Structure

    Science.gov (United States)

    Swaczyna, Paweł; Bzowski, Maciej; Sokół, Justyna M.

    2016-08-01

    Observations of energetic neutral atoms (ENAs) allow for remote studies of the condition of plasma in the heliosphere and the neighboring local interstellar medium. The first results from the Interstellar Boundary Explorer (IBEX) revealed an arc-like enhancement of the ENA intensity in the sky, known as the ribbon. The ribbon was not expected from the heliospheric models prior to the launch of IBEX. One proposed explanation for the ribbon is the mechanism of secondary ENA emission. The ribbon reveals energy-dependent structure in the relative intensity along its circumference and in its position. That is, the geometric center of the ribbon varies systematically by about 10° in the energy range 0.7-4.3 keV. Here, we show by analytical modeling that this effect is a consequence of the helio-latitudinal structure of the solar wind reflected in the secondary ENAs. Along with a recently measured distance to the ribbon’s source just beyond the heliopause, our findings support the connection of the ribbon with the local interstellar magnetic field by the mechanism of secondary ENA emission. However, the magnitude of the center shift in the highest IBEX energy channel is much larger in the observations than expected from the modeling. This may be due to another, not currently recognized, process of ENA generation.

  9. Damage evaluation in metal structures subjected to high energy deposition due to particle beams

    CERN Document Server

    Peroni, L; Dallocchio, A

    2011-01-01

    The unprecedented energy intensities of modern hadron accelerators yield special problems with the materials that are placed close to or into the high intensity beams. The energy stored in a single beam of LHC particle accelerator is equivalent to about 80 kg of TNT explosive, stored in a transverse beam area with a typical value of 0.2 mm×0.2 mm. The materials placed close to the beam are used at, or even beyond, their damage limits. However, it is very difficult to predict structural efficiency and robustness accurately: beam-induced damage for high energy and high intensity occurs in a regime where practical experience does not exist. The interaction between high energy particle beams and metals induces a sudden non uniform temperature increase. This provokes a dynamic response of the structure entailing thermal stress waves and thermally induced vibrations or even the failure of the component. This study is performed in order to estimate the damage on a copper component due to the impact with a 7 TeV pro...

  10. Fractal flame structure due to the hydrodynamic Darrieus-Landau instability.

    Science.gov (United States)

    Yu, Rixin; Bai, Xue-Song; Bychkov, Vitaly

    2015-12-01

    By using large scale numerical simulations, we obtain fractal structure, which develops at originally planar flame fronts due to the hydrodynamic Darrieus-Landau (DL) instability bending the fronts. We clarify some important issues regarding the DL fractal flames, which have been debated for a long time. We demonstrate an increase of the flame propagation speed with the hypothetic channel width, which controls the length scale of the instability development. We show that this increase may be fitted by a power law indicating the mean fractal properties of the flame front structure. The power exponent in this law is found to be not a universal constant, rather it depends on the flame properties-on the density drop at the front. Using box counting on the simulated flame front shapes we show the fractal flame dimension at the intermediate scale is smaller than the one given by the power law, but it has a similar dependency on the density drop. We also obtain a formation of pockets at the DL fractal flame fronts, which previously has been associated only with turbulent burning. PMID:26764824

  11. Structural Growth Trajectories and Rates of Change in the First 3 Months of Infant Brain Development

    Science.gov (United States)

    Holland, Dominic; Chang, Linda; Ernst, Thomas M.; Curran, Megan; Buchthal, Steven D.; Alicata, Daniel; Skranes, Jon; Johansen, Heather; Hernandez, Antonette; Yamakawa, Robyn; Kuperman, Joshua M.; Dale, Anders M.

    2016-01-01

    IMPORTANCE The very early postnatal period witnesses extraordinary rates of growth, but structural brain development in this period has largely not been explored longitudinally. Such assessment may be key in detecting and treating the earliest signs of neurodevelopmental disorders. OBJECTIVE To assess structural growth trajectories and rates of change in the whole brain and regions of interest in infants during the first 3 months after birth. DESIGN, SETTING, AND PARTICIPANTS Serial structural T1-weighted and/or T2-weighted magnetic resonance images were obtained for 211 time points from 87 healthy term-born or term-equivalent preterm-born infants, aged 2 to 90 days, between October 5, 2007, and June 12, 2013. MAIN OUTCOMES AND MEASURES We segmented whole-brain and multiple subcortical regions of interest using a novel application of Bayesian-based methods. We modeled growth and rate of growth trajectories nonparametrically and assessed left-right asymmetries and sexual dimorphisms. RESULTS Whole-brain volume at birth was approximately one-third of healthy elderly brain volume, and did not differ significantly between male and female infants (347 388 mm3 and 335 509 mm3, respectively, P = .12). The growth rate was approximately 1%/d, slowing to 0.4%/d by the end of the first 3 months, when the brain reached just more than half of elderly adult brain volume. Overall growth in the first 90 days was 64%. There was a significant age-by-sex effect leading to widening separation in brain sizes with age between male and female infants (with male infants growing faster than females by 200.4 mm3/d, SE = 67.2, P = .003). Longer gestation was associated with larger brain size (2215 mm3/d, SE = 284, P = 4×10−13). The expected brain size of an infant born one week earlier than average was 5% smaller than average; at 90 days it will not have caught up, being 2% smaller than average. The cerebellum grew at the highest rate, more than doubling in 90 days, and the hippocampus

  12. Structural Neuroimaging Findings in Mild Traumatic Brain Injury.

    Science.gov (United States)

    Bigler, Erin D; Abildskov, Tracy J; Goodrich-Hunsaker, Naomi J; Black, Garrett; Christensen, Zachary P; Huff, Trevor; Wood, Dawn-Marie G; Hesselink, John R; Wilde, Elisabeth A; Max, Jeffrey E

    2016-09-01

    Common neuroimaging findings in mild traumatic brain injury (mTBI), including sport-related concussion (SRC), are reviewed based on computed tomography and magnetic resonance imaging (MRI). Common abnormalities radiologically identified on the day of injury, typically a computed tomographic scan, are in the form of contusions, small subarachnoid or intraparenchymal hemorrhages as well as subdural and epidural collections, edema, and skull fractures. Common follow-up neuroimaging findings with MRI include white matter hyperintensities, hypointense signal abnormalities that reflect prior hemorrhage, focal encephalomalacia, presence of atrophy and/or dilated Virchow-Robins perivascular space. The MRI findings from a large pediatric mTBI study show low frequency of positive MRI findings at 6 months postinjury. The review concludes with an examination of some of the advanced MRI-based image analysis methods that can be performed in the patient who has sustained an mTBI.

  13. Structural Neuroimaging Findings in Mild Traumatic Brain Injury.

    Science.gov (United States)

    Bigler, Erin D; Abildskov, Tracy J; Goodrich-Hunsaker, Naomi J; Black, Garrett; Christensen, Zachary P; Huff, Trevor; Wood, Dawn-Marie G; Hesselink, John R; Wilde, Elisabeth A; Max, Jeffrey E

    2016-09-01

    Common neuroimaging findings in mild traumatic brain injury (mTBI), including sport-related concussion (SRC), are reviewed based on computed tomography and magnetic resonance imaging (MRI). Common abnormalities radiologically identified on the day of injury, typically a computed tomographic scan, are in the form of contusions, small subarachnoid or intraparenchymal hemorrhages as well as subdural and epidural collections, edema, and skull fractures. Common follow-up neuroimaging findings with MRI include white matter hyperintensities, hypointense signal abnormalities that reflect prior hemorrhage, focal encephalomalacia, presence of atrophy and/or dilated Virchow-Robins perivascular space. The MRI findings from a large pediatric mTBI study show low frequency of positive MRI findings at 6 months postinjury. The review concludes with an examination of some of the advanced MRI-based image analysis methods that can be performed in the patient who has sustained an mTBI. PMID:27482782

  14. Posterior reversible encephalopathy syndrome (PRES, an acute neurological syndrome due to reversible multifactorial brain edema: a case report

    Directory of Open Access Journals (Sweden)

    Camilla Cicognani

    2013-04-01

    Full Text Available Background: The essential features of Posterior Reversible Encephalopathy Syndrome (PRES are headache, mental changes, seizures, visual symptoms and often arterial hypertension. Brain RMN typically shows cortico-sottocortical parieto-occipital edema, with a bilateral and symmetric distribution. PRES develops in clinical conditions as hypertensive encephalopathy, preeclampsia/ eclampsia, autoimmune diseases, after transplantation, infections and as an adverse effect of immunosuppressive drugs or chemotherapy. It usually completely reverses with treatment, although permanent sequelae are possible in case of delayed or missed diagnosis. Case report: We describe the case of a transsexual (M!F and tetraplegic patient, admitted for neck and low back pain. She suddenly developed headache, confusion, seizures and severe hypertension with normal blood tests. RMN showed multiple cortico-sottocortical areas of vasogenic and citotoxic edema in temporo-occipital, parietal, frontal, and cerebellar regions. Soon after the beginning of the antihypertensive therapy, clinical recovery was observed, as well as the disappearance of edema at RMN. Discussion and conclusions: Although PRES is usually associated with definite pathological conditions, it is not always the case, as was for the patient here described, who had no predisposing factors in her past clinical history, and presented hypertension only in the acute phase of the syndrome. Since, moreover, PRES usually presents with acute non specific features and it can be misdiagnosed with other serious diseases, the clinician will be helped by the knowledge of this syndrome to promptly start diagnostic workup and treatments, and avoid permanent neurological deficits.

  15. Chronic intermittent fasting improves cognitive functions and brain structures in mice.

    Directory of Open Access Journals (Sweden)

    Liaoliao Li

    Full Text Available Obesity is a major health issue. Obesity started from teenagers has become a major health concern in recent years. Intermittent fasting increases the life span. However, it is not known whether obesity and intermittent fasting affect brain functions and structures before brain aging. Here, we subjected 7-week old CD-1 wild type male mice to intermittent (alternate-day fasting or high fat diet (45% caloric supplied by fat for 11 months. Mice on intermittent fasting had better learning and memory assessed by the Barnes maze and fear conditioning, thicker CA1 pyramidal cell layer, higher expression of drebrin, a dendritic protein, and lower oxidative stress than mice that had free access to regular diet (control mice. Mice fed with high fat diet was obese and with hyperlipidemia. They also had poorer exercise tolerance. However, these obese mice did not present significant learning and memory impairment or changes in brain structures or oxidative stress compared with control mice. These results suggest that intermittent fasting improves brain functions and structures and that high fat diet feeding started early in life does not cause significant changes in brain functions and structures in obese middle-aged animals.

  16. In vivo three-photon microscopy of subcortical structures within an intact mouse brain

    Science.gov (United States)

    Horton, Nicholas G.; Wang, Ke; Kobat, Demirhan; Clark, Catharine G.; Wise, Frank W.; Schaffer, Chris B.; Xu, Chris

    2013-03-01

    Two-photon fluorescence microscopy enables scientists in various fields including neuroscience, embryology and oncology to visualize in vivo and ex vivo tissue morphology and physiology at a cellular level deep within scattering tissue. However, tissue scattering limits the maximum imaging depth of two-photon fluorescence microscopy to the cortical layer within mouse brain, and imaging subcortical structures currently requires the removal of overlying brain tissue or the insertion of optical probes. Here, we demonstrate non-invasive, high-resolution, in vivo imaging of subcortical structures within an intact mouse brain using three-photon fluorescence microscopy at a spectral excitation window of 1,700 nm. Vascular structures as well as red fluorescent protein-labelled neurons within the mouse hippocampus are imaged. The combination of the long excitation wavelength and the higher-order nonlinear excitation overcomes the limitations of two-photon fluorescence microscopy, enabling biological investigations to take place at a greater depth within tissue.

  17. Structural and functional rich club organization of the brain in children and adults.

    Directory of Open Access Journals (Sweden)

    David S Grayson

    Full Text Available Recent studies using Magnetic Resonance Imaging (MRI have proposed that the brain's white matter is organized as a rich club, whereby the most highly connected regions of the brain are also highly connected to each other. Here we use both functional and diffusion-weighted MRI in the human brain to investigate whether the rich club phenomena is present with functional connectivity, and how this organization relates to the structural phenomena. We also examine whether rich club regions serve to integrate information between distinct brain systems, and conclude with a brief investigation of the developmental trajectory of rich-club phenomena. In agreement with prior work, both adults and children showed robust structural rich club organization, comprising regions of the superior medial frontal/dACC, medial parietal/PCC, insula, and inferior temporal cortex. We also show that these regions were highly integrated across the brain's major networks. Functional brain networks were found to have rich club phenomena in a similar spatial layout, but a high level of segregation between systems. While no significant differences between adults and children were found structurally, adults showed significantly greater functional rich club organization. This difference appeared to be driven by a specific set of connections between superior parietal, insula, and supramarginal cortex. In sum, this work highlights the existence of both a structural and functional rich club in adult and child populations with some functional changes over development. It also offers a potential target in examining atypical network organization in common developmental brain disorders, such as ADHD and Autism.

  18. Overlapping communities reveal rich structure in large-scale brain networks during rest and task conditions.

    Science.gov (United States)

    Najafi, Mahshid; McMenamin, Brenton W; Simon, Jonathan Z; Pessoa, Luiz

    2016-07-15

    Large-scale analysis of functional MRI data has revealed that brain regions can be grouped into stable "networks" or communities. In many instances, the communities are characterized as relatively disjoint. Although recent work indicates that brain regions may participate in multiple communities (for example, hub regions), the extent of community overlap is poorly understood. To address these issues, here we investigated large-scale brain networks based on "rest" and task human functional MRI data by employing a mixed-membership Bayesian model that allows each brain region to belong to all communities simultaneously with varying membership strengths. The approach allowed us to 1) compare the structure of disjoint and overlapping communities; 2) determine the relationship between functional diversity (how diverse is a region's functional activation repertoire) and membership diversity (how diverse is a region's affiliation to communities); 3) characterize overlapping community structure; 4) characterize the degree of non-modularity in brain networks; 5) study the distribution of "bridges", including bottleneck and hub bridges. Our findings revealed the existence of dense community overlap that was not limited to "special" hubs. Furthermore, the findings revealed important differences between community organization during rest and during specific task states. Overall, we suggest that dense overlapping communities are well suited to capture the flexible and task dependent mapping between brain regions and their functions. PMID:27129758

  19. Brain structure correlates of urban upbringing, an environmental risk factor for schizophrenia.

    Science.gov (United States)

    Haddad, Leila; Schäfer, Axel; Streit, Fabian; Lederbogen, Florian; Grimm, Oliver; Wüst, Stefan; Deuschle, Michael; Kirsch, Peter; Tost, Heike; Meyer-Lindenberg, Andreas

    2015-01-01

    Urban upbringing has consistently been associated with schizophrenia, but which specific environmental exposures are reflected by this epidemiological observation and how they impact the developing brain to increase risk is largely unknown. On the basis of prior observations of abnormal functional brain processing of social stress in urban-born humans and preclinical evidence for enduring structural brain effects of early social stress, we investigated a possible morphological correlate of urban upbringing in human brain. In a sample of 110 healthy subjects studied with voxel-based morphometry, we detected a strong inverse correlation between early-life urbanicity and gray matter (GM) volume in the right dorsolateral prefrontal cortex (DLPFC, Brodmann area 9). Furthermore, we detected a negative correlation of early-life urbanicity and GM volumes in the perigenual anterior cingulate cortex (pACC) in men only. Previous work has linked volume reductions in the DLPFC to the exposure to psychosocial stress, including stressful experiences in early life. Besides, anatomical and functional alterations of this region have been identified in schizophrenic patients and high-risk populations. Previous data linking functional hyperactivation of pACC during social stress to urban upbringing suggest that the present interaction effect in brain structure might contribute to an increased risk for schizophrenia in males brought up in cities. Taken together, our results suggest a neural mechanism by which early-life urbanicity could impact brain architecture to increase the risk for schizophrenia. PMID:24894884

  20. Uncovering latent deficits due to mild traumatic brain injury (mTBI by using normobaric hypoxia stress

    Directory of Open Access Journals (Sweden)

    Leonard eTemme

    2013-04-01

    Full Text Available Memory deficits and other cognitive symptoms frequently associated with mTBI are commonly thought to resolve within 7 to 10 days. This generalization is based principally on observations made in individuals who are in the unstressed environmental conditions typical to a clinic and so does not consider the impact of physiologic, environmental or psychological stress. Normobaric Hypoxia (NH stress can be generated by mixing normal mean sea level air (MSL containing 21% oxygen (O2 with nitrogen, which is biologically inert, so that the resultant mixed gas has a partial pressure of O2 approximating that of specified altitudes. This technique was used to generate NH equivalents of 8,000, 12,000 and 14,000 feet above MSL in a group of 36 volunteers with an mTBI history and an equal number of controls matched on the basis of age, gender, weight, etc. Short term visual memory was tested using Matching to Sample (M2S subtest of the BrainCheckers analogue of the Automated Neuropsychological Assessment Metrics (ANAM. Although there were no significant differences in M2S performance between the two groups of subjects at MSL, with increased altitude, performance deteriorated in the mTBI group as predicted to be significantly worse than that of the controls. When the subjects were returned to MSL, the difference disappeared. This finding suggests that the hypoxic challenge paradigm developed here has potential clinical utility for assessing the effects of mTBI in individuals who appear asymptomatic under normal conditions.

  1. Human Development XII: A Theory for the Structure and Function of the Human Brain

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2008-01-01

    Full Text Available The human brain is probably the most complicated single structure in the biological universe. The cerebral cortex that is traditionally connected with consciousness is extremely complex. The brain contains approximately 1,000,000 km of nerve fibers, indicating its enormous complexity and which makes it difficult for scientists to reveal the function of the brain. In this paper, we propose a new model for brain functions, i.e., information-guided self-organization of neural patterns, where information is provided from the abstract wholeness of the biophysical system of an organism (often called the true self, or the “soul””. We present a number of arguments in favor of this model that provide self-conscious control over the thought process or cognition. Our arguments arise from analyzing experimental data from different research fields: histology, anatomy, electroencephalography (EEG, cerebral blood flow, neuropsychology, evolutionary studies, and mathematics. We criticize the popular network theories as the consequence of a simplistic, mechanical interpretation of reality (philosophical materialism applied to the brain. We demonstrate how viewing brain functions as information-guided self-organization of neural patterns can explain the structure of conscious mentation; we seem to have a dual hierarchical representation in the cerebral cortex: one for sensation-perception and one for will-action. The model explains many of our unique mental abilities to think, memorize, associate, discriminate, and make abstractions. The presented model of the conscious brain also seems to be able to explain the function of the simpler brains, such as those of insects and hydra.

  2. Human development XII: a theory for the structure and function of the human brain.

    Science.gov (United States)

    Ventegodt, Søren; Hermansen, Tyge Dahl; Kandel, Isack; Merrick, Joav

    2008-01-01

    The human brain is probably the most complicated single structure in the biological universe. The cerebral cortex that is traditionally connected with consciousness is extremely complex. The brain contains approximately 1,000,000 km of nerve fibers, indicating its enormous complexity and which makes it difficult for scientists to reveal the function of the brain. In this paper, we propose a new model for brain functions, i.e., information-guided self-organization of neural patterns, where information is provided from the abstract wholeness of the biophysical system of an organism (often called the true self, or the "soul"). We present a number of arguments in favor of this model that provide self-conscious control over the thought process or cognition. Our arguments arise from analyzing experimental data from different research fields: histology, anatomy, electroencephalography (EEG), cerebral blood flow, neuropsychology, evolutionary studies, and mathematics. We criticize the popular network theories as the consequence of a simplistic, mechanical interpretation of reality (philosophical materialism) applied to the brain. We demonstrate how viewing brain functions as information-guided self-organization of neural patterns can explain the structure of conscious mentation; we seem to have a dual hierarchical representation in the cerebral cortex: one for sensation-perception and one for will-action. The model explains many of our unique mental abilities to think, memorize, associate, discriminate, and make abstractions. The presented model of the conscious brain also seems to be able to explain the function of the simpler brains, such as those of insects and hydra. PMID:18661051

  3. Characterization of the Community Structure of Large Scale Functional Brain Networks During Ketamine-Medetomidine Anesthetic Induction

    OpenAIRE

    Padovani, Eduardo C.

    2016-01-01

    One of the central questions in neuroscience is to understand the way communication is organized in the brain, trying to comprehend how cognitive capacities or physiological states of the organism are potentially related to brain activities involving interactions of several brain areas. One important characteristic of the functional brain networks is that they are modularly structured, being this modular architecture regarded to account for a series of properties and functional dynamics. In t...

  4. Advanced Structural and Functional Brain MRI in Multiple Sclerosis.

    Science.gov (United States)

    Giorgio, Antonio; De Stefano, Nicola

    2016-04-01

    Conventional magnetic resonance imaging (MRI) of the central nervous system is crucial for an early and reliable diagnosis and monitoring of patients with multiple sclerosis (MS). Focal white matter (WM) lesions, as detected by MRI, are the pathological hallmark of the disease and show some relation to clinical disability, especially in the long run. Gray matter (GM) involvement is evident from disease onset and includes focal (i.e., cortical lesions) and diffuse pathology (i.e., atrophy). Both accumulate over time and show close relation to physical disability and cognitive impairment. Using advanced quantitative MRI techniques such as magnetization transfer imaging (MTI), diffusion tensor imaging (DTI), proton MR spectroscopy ((1)H-MRS), and iron imaging, subtle MS pathology has been demonstrated from early stages outside focal WM lesions in the form of widespread abnormalities of the normal appearing WM and GM. In addition, studies using functional MRI have demonstrated that brain plasticity is driven by MS pathology, playing adaptive or maladaptive roles to neurologic and cognitive status and explaining, at least in part, the clinicoradiological paradox of MS. PMID:27116723

  5. Shifting brain asymmetry: the link between meditation and structural lateralization

    Science.gov (United States)

    Kurth, Florian; MacKenzie-Graham, Allan; Toga, Arthur W.

    2015-01-01

    Previous studies have revealed an increased fractional anisotropy and greater thickness in the anterior parts of the corpus callosum in meditation practitioners compared with control subjects. Altered callosal features may be associated with an altered inter-hemispheric integration and the degree of brain asymmetry may also be shifted in meditation practitioners. Therefore, we investigated differences in gray matter asymmetry as well as correlations between gray matter asymmetry and years of meditation practice in 50 long-term meditators and 50 controls. We detected a decreased rightward asymmetry in the precuneus in meditators compared with controls. In addition, we observed that a stronger leftward asymmetry near the posterior intraparietal sulcus was positively associated with the number of meditation practice years. In a further exploratory analysis, we observed that a stronger rightward asymmetry in the pregenual cingulate cortex was negatively associated with the number of practice years. The group difference within the precuneus, as well as the positive correlations with meditation years in the pregenual cingulate cortex, suggests an adaptation of the default mode network in meditators. The positive correlation between meditation practice years and asymmetry near the posterior intraparietal sulcus may suggest that meditation is accompanied by changes in attention processing. PMID:24643652

  6. ELECTRON MICROSCOPY OF SYNAPTIC STRUCTURE OF OCTOPUS BRAIN.

    Science.gov (United States)

    GRAY, E G; YOUNG, J Z

    1964-04-01

    The well known type of synapse between a presynaptic process containing vesicles and a "clear" postsynaptic process can be commonly observed in the various lobes of the brain of Octopus. The presynaptic vesicles are aggregated near regions of the synaptic membranes which show specialisation and asymmetric "thickening" indicating functional polarisation, and here chemical transmission is presumed to take place. In addition, in the vertical lobe a very interesting serial arrangement of synaptic contacts occurs. Presynaptic bags, formed from varicosities of fibres from the superior frontal lobe, contact the trunks of amacrine cells in the manner just described. The trunks, however, although apparently postsynaptic are themselves packed with synaptic vesicles. The trunks, in turn, make "presynaptic" contacts with clear spinous processes of other neurons of yet undetermined origin. Typical polarised membrane specialisations occur at the contact regions. The trunk vesicles aggregated closest to the contact regions have a shell of particles round their walls. At present, there is no way of telling whether the membrane conductance to the various ions is differently affected at either of the transmission sites, and, if an inhibitory mechanism is involved, whether it is of the presynaptic or postsynaptic variety. PMID:14154498

  7. Deep Independence Network Analysis of Structural Brain Imaging: Application to Schizophrenia.

    Science.gov (United States)

    Castro, Eduardo; Hjelm, R Devon; Plis, Sergey M; Dinh, Laurent; Turner, Jessica A; Calhoun, Vince D

    2016-07-01

    Linear independent component analysis (ICA) is a standard signal processing technique that has been extensively used on neuroimaging data to detect brain networks with coherent brain activity (functional MRI) or covarying structural patterns (structural MRI). However, its formulation assumes that the measured brain signals are generated by a linear mixture of the underlying brain networks and this assumption limits its ability to detect the inherent nonlinear nature of brain interactions. In this paper, we introduce nonlinear independent component estimation (NICE) to structural MRI data to detect abnormal patterns of gray matter concentration in schizophrenia patients. For this biomedical application, we further addressed the issue of model regularization of nonlinear ICA by performing dimensionality reduction prior to NICE, together with an appropriate control of the complexity of the model and the usage of a proper approximation of the probability distribution functions of the estimated components. We show that our results are consistent with previous findings in the literature, but we also demonstrate that the incorporation of nonlinear associations in the data enables the detection of spatial patterns that are not identified by linear ICA. Specifically, we show networks including basal ganglia, cerebellum and thalamus that show significant differences in patients versus controls, some of which show distinct nonlinear patterns. PMID:26891483

  8. The influence of sex steroids on structural brain maturation in adolescence.

    Science.gov (United States)

    Koolschijn, P Cédric M P; Peper, Jiska S; Crone, Eveline A

    2014-01-01

    Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls.

  9. The influence of sex steroids on structural brain maturation in adolescence.

    Directory of Open Access Journals (Sweden)

    P Cédric M P Koolschijn

    Full Text Available Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (subcortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls.

  10. Towards the "baby connectome": mapping the structural connectivity of the newborn brain.

    Directory of Open Access Journals (Sweden)

    Olga Tymofiyeva

    Full Text Available Defining the structural and functional connectivity of the human brain (the human "connectome" is a basic challenge in neuroscience. Recently, techniques for noninvasively characterizing structural connectivity networks in the adult brain have been developed using diffusion and high-resolution anatomic MRI. The purpose of this study was to establish a framework for assessing structural connectivity in the newborn brain at any stage of development and to show how network properties can be derived in a clinical cohort of six-month old infants sustaining perinatal hypoxic ischemic encephalopathy (HIE. Two different anatomically unconstrained parcellation schemes were proposed and the resulting network metrics were correlated with neurological outcome at 6 months. Elimination and correction of unreliable data, automated parcellation of the cortical surface, and assembling the large-scale baby connectome allowed an unbiased study of the network properties of the newborn brain using graph theoretic analysis. In the application to infants with HIE, a trend to declining brain network integration and segregation was observed with increasing neuromotor deficit scores.

  11. Structural and Functional MRI Differences in Master Sommeliers: A Pilot Study on Expertise in the Brain.

    Science.gov (United States)

    Banks, Sarah J; Sreenivasan, Karthik R; Weintraub, David M; Baldock, Deanna; Noback, Michael; Pierce, Meghan E; Frasnelli, Johannes; James, Jay; Beall, Erik; Zhuang, Xiaowei; Cordes, Dietmar; Leger, Gabriel C

    2016-01-01

    Our experiences, even as adults, shape our brains. Regional differences have been found in experts, with the regions associated with their particular skill-set. Functional differences have also been noted in brain activation patterns in some experts. This study uses multimodal techniques to assess structural and functional patterns that differ between experts and non-experts. Sommeliers are experts in wine and thus in olfaction. We assessed differences in Master Sommeliers' brains, compared with controls, in structure and also in functional response to olfactory and visual judgment tasks. MRI data were analyzed using voxel-based morphometry as well as automated parcellation to assess structural properties, and group differences between tasks were calculated. Results indicate enhanced volume in the right insula and entorhinal cortex, with the cortical thickness of the entorhinal correlating with experience. There were regional activation differences in a large area involving the right olfactory and memory regions, with heightened activation specifically for sommeliers during an olfactory task. Our results indicate that sommeliers' brains show specialization in the expected regions of the olfactory and memory networks, and also in regions important in integration of internal sensory stimuli and external cues. Overall, these differences suggest that specialized expertise and training might result in enhancements in the brain well into adulthood. This is particularly important given the regions involved, which are the first to be impacted by many neurodegenerative diseases. PMID:27597821

  12. Deep Independence Network Analysis of Structural Brain Imaging: Application to Schizophrenia

    Science.gov (United States)

    Castro, Eduardo; Hjelm, R. Devon; Plis, Sergey M.; Dinh, Laurent; Turner, Jessica A.; Calhoun, Vince D.

    2016-01-01

    Linear independent component analysis (ICA) is a standard signal processing technique that has been extensively used on neuroimaging data to detect brain networks with coherent brain activity (functional MRI) or covarying structural patterns (structural MRI). However, its formulation assumes that the measured brain signals are generated by a linear mixture of the underlying brain networks and this assumption limits its ability to detect the inherent nonlinear nature of brain interactions. In this paper, we introduce nonlinear independent component estimation (NICE) to structural MRI data to detect abnormal patterns of gray matter concentration in schizophrenia patients. For this biomedical application, we further addressed the issue of model regularization of nonlinear ICA by performing dimensionality reduction prior to NICE, together with an appropriate control of the complexity of the model and the usage of a proper approximation of the probability distribution functions of the estimated components. We show that our results are consistent with previous findings in the literature, but we also demonstrate that the incorporation of nonlinear associations in the data enables the detection of spatial patterns that are not identified by linear ICA. Specifically, we show networks including basal ganglia, cerebellum and thalamus that show significant differences in patients versus controls, some of which show distinct nonlinear patterns. PMID:26891483

  13. ErbB4 in Laminated Brain Structures: A Neurodevelopmental Approach to Schizophrenia

    Science.gov (United States)

    Perez-Garcia, Carlos G.

    2015-01-01

    The susceptibility genes for schizophrenia Neuregulin-1 (NRG1) and ErbB4 have critical functions during brain development and in the adult. Alterations in the ErbB4 signaling pathway cause a variety of neurodevelopmental defects including deficiencies in neuronal migration, synaptic plasticity, and myelination. I have used the ErbB4-/- HER4heart KO mice to study the neurodevelopmental insults associated to deficiencies in the NRG1-ErbB4 signaling pathway and their potential implication with brain disorders such as schizophrenia, a chronic psychiatric disease affecting 1% of the population worldwide. ErbB4 deletion results in an array of neurodevelopmental deficits that are consistent with a schizophrenic model. First, similar defects appear in multiple brain structures, from the cortex to the cerebellum. Second, these defects affect multiple aspects of brain development, from deficits in neuronal migration to impairments in excitatory/inhibitory systems, including reductions in brain volume, cortical and cerebellar heterotopias, alterations in number and distribution of specific subpopulations of interneurons, deficiencies in the astrocytic and oligodendrocytic lineages, and additional insults in major brain structures. This suggests that alterations in specific neurodevelopmental genes that play similar functions in multiple neuroanatomical structures might account for some of the symptomatology observed in schizophrenic patients, such as defects in cognition. ErbB4 mutation uncovers flaws in brain development that are compatible with a neurodevelopmental model of schizophrenia, and it establishes a comprehensive model to study the basis of the disorder before symptoms are detected in the adult. PMID:26733804

  14. ErbB4 in laminated brain structures: a neurodevelopmental approach to schizophrenia

    Directory of Open Access Journals (Sweden)

    Carlos Gustavo Perez-Garcia

    2015-12-01

    Full Text Available The susceptibility genes for schizophrenia Neuregulin-1 (NRG1 and ErbB4 have critical functions during brain development and in the adult. Alterations in the ErbB4 signaling pathway cause a variety of neurodevelopmental defects including deficiencies in neuronal migration, synaptic plasticity and myelination. I have used the ErbB4-/- HER4heart KO mice to study the neurodevelopmental insults associated to deficiencies in the NRG1-ErbB4 signaling pathway and their potential implication with brain disorders such as schizophrenia, a chronic psychiatric disease affecting 1% of the population worldwide. ErbB4 deletion results in an array of neurodevelopmental deficits that are consistent with a schizophrenic model. First, similar defects appear in multiple brain structures, from the cortex to the cerebellum. Second, these defects affect multiple aspects of brain development, from deficits in neuronal migration to impairments in excitatory/inhibitory systems, including reductions in brain volume, cortical and cerebellar heteropias, alterations in number and distribution of specific subpopulations of interneurons, deficiencies in the astrocytic and oligodendrocytic lineages, and additional insults in major brain structures. This suggests that alterations in specific neurodevelopmental genes that play similar functions in multiple neuroanatomical structures might account for some of the symptomatology observed in schizophrenic patients, such as defects in cognition. ErbB4 mutation uncovers flaws in brain development that are compatible with a neurodevelopmental model of schizophrenia, and it establishes a comprehensive model to study the basis of the disorder before symptoms are detected in the adult.

  15. Statistical properties of the convergence due to weak gravitational lensing by non-linear structures

    CERN Document Server

    Valageas, P

    2000-01-01

    Density fluctuations in the matter distribution lead to distortions of the images of distant galaxies through weak gravitational lensing effects. This provides an efficient probe of the cosmological parameters and of the density field. In this article, we investigate the statistical properties of the convergence due to weak gravitational lensing by non-linear structures (i.e. we consider small angular windows $\\theta \\la 1'$). Previous studies have shown how to relate the second and third order moments of the convergence to those of the density contrast while models based on the Press-Schechter prescription provide an estimate of the tail of $P(\\kappa)$. Here we present a method to obtain an estimate of the full p.d.f. of the convergence $P(\\kappa)$. It is based on a realistic description of the density field which applies to overdense as well as underdense regions. We show that our predictions agree very well with the results of N-body simulations for the convergence. This could allow one to derive the cosmo...

  16. Mechanical behavior of the LMFBR core structure under transient pressure due to local failure

    International Nuclear Information System (INIS)

    A satisfactory fast reactor safety analysis requires a comprehensive experimental and theoretical research program. The structural integrity of the reactor core in case of any local failure has to be demonstrated. Such local events may be due to random pin failure which is very likely. As a consequence contact between molten fuel and coolant may occur. The existing uncertainties in the understanding of the physical mechanisms observed during this molten fuel-coolant-interaction (MFCI) emphasize the importance of the comprehensiveness of this research program. This paper describes the effort done at GfK Karlsruhe in cooperation with UKAEA and EURATOM to predict the core deformations caused by local failure within an LMFBR core. These activities try to cover all important questions currently discussed in the analysis of possible core damage. It may be concluded that the reactor can be scrammed in time under pessimistic-realistic pressure transients and that the deformations do not exceed tolerable limits. The computer methods are general enough as to allow for different core designs with varying geometries, material properties, etc. (Auth.)

  17. Changes in the structure due to strong winds in forest areas in the Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    Suzana Maria Salis

    2012-09-01

    Full Text Available The Pantanal climate presents marked seasonality and eventually strong winds occur, especially in the beginning of the rainy season, which may last from September or October until April. A phytosociological study was conducted to evaluate the effects of a strong wind on the composition and structure of two forest formations in Pantanal wetland, a semideciduous forest (19º 15’ 32’’S and 55º 45’ 23.7’’W and a forested savanna - “cerradão” (19° 17’ 21’’S and 55º 45’ 8.9’’W, with trees with diameter at breast height (DBH ≥ 5 cm. After the strong wind, a reduction of 6% of the basal area and volume in the semideciduous forest was observed, mainly due to the uprooting of Xylopia aromatica trees. In the forested savanna, the basal area and volume reduction was even higher; an estimated 10%, representing 69 uprooted trees per hectare, mainly of Copaifera martii trees. In both areas it was observed that the uprooted trees presented an average height and diameter bigger than the trees that remained intact. Usually, the trees that were uprooted presented higher wood density and the species that had broken branches had a lower density.

  18. MTR variations in normal adult brain structures using balanced steady-state free precession

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Meritxell; Wetzel, Stephan G.; Radue, Ernst-Wilhelm [University of Basel Hospital, Department of Neuroradiology, Institute of Radiology, Basel (Switzerland); Gloor, Monika; Bieri, Oliver; Scheffler, Klaus [University of Basel Hospital, Division of Radiological Physics, Institute of Radiology, Basel (Switzerland)

    2011-03-15

    Magnetization transfer (MT) is sensitive to the macromolecular environment of water protons and thereby provides information not obtainable from conventional magnetic resonance imaging (MRI). Compared to standard methods, MT-sensitized balanced steady-state free precession (bSSFP) offers high-resolution images with significantly reduced acquisition times. In this study, high-resolution magnetization transfer ratio (MTR) images from normal appearing brain structures were acquired with bSSFP. Twelve subjects were studied on a 1.5 T scanner. MTR values were calculated from MT images acquired in 3D with 1.3 mm isotropic resolution. The complete MT data set was acquired within less than 3.5 min. Forty-one brain structures of the white matter (WM) and gray matter (GM) were identified for each subject. MTR values were higher for WM than GM. In general, MTR values of the WM and GM structures were in good accordance with the literature. However, MTR values showed more homogenous values within WM and GM structures than previous studies. MT-sensitized bSSFP provides isotropic high-resolution MTR images and hereby allows assessment of reliable MTR data in also very small brain structures in clinically feasible acquisition times and is thus a promising sequence for being widely used in the clinical routine. The present normative data can serve as a reference for the future characterization of brain pathologies. (orig.)

  19. Functional and Structural Brain Changes Associated with Methamphetamine Abuse

    Directory of Open Access Journals (Sweden)

    Bruce R. Russell

    2012-10-01

    Full Text Available Methamphetamine (MA is a potent psychostimulant drug whose abuse has become a global epidemic in recent years. Firstly, this review article briefly discusses the epidemiology and clinical pharmacology of methamphetamine dependence. Secondly, the article reviews relevant animal literature modeling methamphetamine dependence and discusses possible mechanisms of methamphetamine-induced neurotoxicity. Thirdly, it provides a critical review of functional and structural neuroimaging studies in human MA abusers; including positron emission tomography (PET and functional and structural magnetic resonance imaging (MRI. The effect of abstinence from methamphetamine, both short- and long-term within the context of these studies is also reviewed.

  20. The Effects of Video Games on Cognition and Brain Structure: Potential Implications for Neuropsychiatric Disorders.

    Science.gov (United States)

    Shams, Tahireh A; Foussias, George; Zawadzki, John A; Marshe, Victoria S; Siddiqui, Ishraq; Müller, Daniel J; Wong, Albert H C

    2015-09-01

    Video games are now a ubiquitous form of entertainment that has occasionally attracted negative attention. Video games have also been used to test cognitive function, as therapeutic interventions for neuropsychiatric disorders, and to explore mechanisms of experience-dependent structural brain changes. Here, we review current research on video games published from January 2011 to April 2014 with a focus on studies relating to mental health, cognition, and brain imaging. Overall, there is evidence that specific types of video games can alter brain structure or improve certain aspects of cognitive functioning. Video games can also be useful as neuropsychological assessment tools. While research in this area is still at a very early stage, there are interesting results that encourage further work in this field, and hold promise for utilizing this technology as a powerful therapeutic and experimental tool.

  1. The Effects of Video Games on Cognition and Brain Structure: Potential Implications for Neuropsychiatric Disorders.

    Science.gov (United States)

    Shams, Tahireh A; Foussias, George; Zawadzki, John A; Marshe, Victoria S; Siddiqui, Ishraq; Müller, Daniel J; Wong, Albert H C

    2015-09-01

    Video games are now a ubiquitous form of entertainment that has occasionally attracted negative attention. Video games have also been used to test cognitive function, as therapeutic interventions for neuropsychiatric disorders, and to explore mechanisms of experience-dependent structural brain changes. Here, we review current research on video games published from January 2011 to April 2014 with a focus on studies relating to mental health, cognition, and brain imaging. Overall, there is evidence that specific types of video games can alter brain structure or improve certain aspects of cognitive functioning. Video games can also be useful as neuropsychological assessment tools. While research in this area is still at a very early stage, there are interesting results that encourage further work in this field, and hold promise for utilizing this technology as a powerful therapeutic and experimental tool. PMID:26216589

  2. Brief report: CANTAB performance and brain structure in pediatric patients with Asperger syndrome.

    Science.gov (United States)

    Kaufmann, Liane; Zotter, Sibylle; Pixner, Silvia; Starke, Marc; Haberlandt, Edda; Steinmayr-Gensluckner, Maria; Egger, Karl; Schocke, Michael; Weiss, Elisabeth M; Marksteiner, Josef

    2013-06-01

    By merging neuropsychological (CANTAB/cambridge neuropsychological test automated battery) and structural brain imaging data (voxel-based-morphometry) the present study sought to identify the neurocognitive correlates of executive functions in individuals with Asperger syndrome (AS) compared to healthy controls. Results disclosed subtle group differences regarding response speed on only one CANTAB subtest that is thought to tap fronto-executive network functions (SWM/spatial working memory). Across all participants, SWM performance was significantly associated with two brain regions (precentral gyrus white matter, precuneus grey matter), thus suggesting a close link between fronto-executive functions (SWM) and circumscribed fronto-parietal brain structures. Finally, symptom severity (ADOS total score) was best predicted by response speed on a set-shifting task (IES) thought to tap fronto-striatal functions (corrected R2 56%).

  3. Multivariate genetic analysis of brain structure in an extended twin design

    DEFF Research Database (Denmark)

    Posthuma, D; de Geus, E.J.; Neale, M.C.;

    2000-01-01

    quantitative scale and thus can be assessed in affected and unaffected individuals. Continuous measures increase the statistical power to detect genetic effects (Neale et al., 1994), and allow studies to be designed to collect data from informative subjects such as extreme concordant or discordant pairs....... Intermediate phenotypes for discrete traits, such as psychiatric disorders, can be neurotransmitter levels, brain function, or structure. In this paper we conduct a multivariate analysis of data from 111 twin pairs and 34 additional siblings on cerebellar volume, intracranial space, and body height....... The analysis is carried out on the raw data and specifies a model for the mean and the covariance structure. Results suggest that cerebellar volume and intracranial space vary with age and sex. Brain volumes tend to decrease slightly with age, and males generally have a larger brain volume than females...

  4. Three-dimensional structure of brain tissue at submicrometer resolution

    International Nuclear Information System (INIS)

    Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography

  5. Three-dimensional structure of brain tissue at submicrometer resolution

    Energy Technology Data Exchange (ETDEWEB)

    Saiga, Rino; Mizutani, Ryuta, E-mail: ryuta@tokai-u.jp [Department of Applied Biochemistry, Tokai University, Hiratsuka, Kanagawa 259-1292 (Japan); Inomoto, Chie; Takekoshi, Susumu; Nakamura, Naoya; Tsuboi, Akio; Osawa, Motoki [Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Arai, Makoto; Oshima, Kenichi; Itokawa, Masanari [Tokyo Metropolitan Institute of Medical Science, Setagaya, Tokyo 156-8506 (Japan); Uesugi, Kentaro; Takeuchi, Akihisa; Terada, Yasuko; Suzuki, Yoshio [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 (Japan)

    2016-01-28

    Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography.

  6. Distinctive structures between chimpanzee and humanin a brain noncoding RNA

    OpenAIRE

    Beniaminov, Artemy; Westhof, Eric; Krol, Alain

    2008-01-01

    Human accelerated region 1 (HAR1) is a short DNA region identified recently to have evolved the most rapidly among highly constrained regions since the divergence from our common ancestor with chimpanzee. It is transcribed as part of a noncoding RNA specifically expressed in the developing human neocortex. Employing a panoply of enzymatic and chemical probes, our analysis of HAR1 RNA proposed a secondary structure model differing from that published. Most surprisingly, we discovered that the ...

  7. Nonparametric Bayesian Clustering of Structural Whole Brain Connectivity in Full Image Resolution

    DEFF Research Database (Denmark)

    Ambrosen, Karen Marie Sandø; Albers, Kristoffer Jon; Dyrby, Tim B.;

    2014-01-01

    Diffusion magnetic resonance imaging enables measuring the structural connectivity of the human brain at a high spatial resolution. Local noisy connectivity estimates can be derived using tractography approaches and statistical models are necessary to quantify the brain’s salient structural organ...... can aid in understanding the underlying connectivity patterns, and the proposed method for large scale data driven generation of structural units provides a promising framework that can exploit the increasing spatial resolution of neuro-imaging technologies.......Diffusion magnetic resonance imaging enables measuring the structural connectivity of the human brain at a high spatial resolution. Local noisy connectivity estimates can be derived using tractography approaches and statistical models are necessary to quantify the brain’s salient structural...... groups) that defines structural units at the resolution of statistical support. We apply the model to a network of structural brain connectivity in full image resolution with more than one hundred thousand regions (voxels in the gray-white matter boundary) and around one hundred million connections. The...

  8. Brain structure across the lifespan: the influence of stress and mood

    Directory of Open Access Journals (Sweden)

    Jose Miguel Soares

    2014-11-01

    Full Text Available Normal brain aging is an inevitable and heterogeneous process characterized by a selective pattern of structural changes. Such heterogeneity arises as a consequence of cumulative effects over the lifespan, including stress and mood effects, which drive different micro- and macro-structural alterations in the brain. Investigating these differences in healthy age-related changes is a major challenge for the comprehension of the cognitive status. Herein we addressed the impact of normal aging, stress, mood and their interplay in the brain gray and white matter structure. We showed the critical impact of age in the white matter volume and how stress and mood influence brain volumetry across the lifespan. Moreover, we found a more profound effect of the interaction of aging/stress/mood on structures located in the left hemisphere. These findings help to clarify some divergent results associated with the aging decline and to enlighten the association between abnormal volumetric alterations and several states that may lead to psychiatric disorders.

  9. Anomalous Development of Brain Structure and Function in Spina Bifida Myelomeningocele

    Science.gov (United States)

    Juranek, Jenifer; Salman, Michael S.

    2010-01-01

    Spina bifida myelomeningocele (SBM) is a specific type of neural tube defect whereby the open neural tube at the level of the spinal cord alters brain development during early stages of gestation. Some structural anomalies are virtually unique to individuals with SBM, including a complex pattern of cerebellar dysplasia known as the Chiari II…

  10. Rewiring the Corporate Brain: Using the New Science To Rethink How We Structure and Lead Organizations.

    Science.gov (United States)

    Zohar, Danah

    This book relates the radically new sciences of the 20th century--quantum mechanics, chaos theory, and complexity theory--to organizational problems and challenges facing corporate leaders. The book draws on the science of the human brain, with its three different kinds of neural structures--mental, emotional, and spiritual--to illustrate how to…

  11. Brief Report: CANTAB Performance and Brain Structure in Pediatric Patients with Asperger Syndrome

    Science.gov (United States)

    Kaufmann, Liane; Zotter, Sibylle; Pixner, Silvia; Starke, Marc; Haberlandt, Edda; Steinmayr-Gensluckner, Maria; Egger, Karl; Schocke, Michael; Weiss, Elisabeth M.; Marksteiner, Josef

    2013-01-01

    By merging neuropsychological (CANTAB/Cambridge Neuropsychological Test Automated Battery) and structural brain imaging data (voxel-based-morphometry) the present study sought to identify the neurocognitive correlates of executive functions in individuals with Asperger syndrome (AS) compared to healthy controls. Results disclosed subtle group…

  12. Co-Localisation of Abnormal Brain Structure and Function in Specific Language Impairment

    Science.gov (United States)

    Badcock, Nicholas A.; Bishop, Dorothy V. M.; Hardiman, Mervyn J.; Barry, Johanna G.; Watkins, Kate E.

    2012-01-01

    We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior…

  13. Differential effects of the ApoE4 genotype on brain structure and function

    NARCIS (Netherlands)

    Matura, S.; Prvulovic, D.; Jurcoane, A.; Hartmann, D.; Miller, J.; Scheibe, M.; O'Dwyer, L.G.; Oertel-Knochel, V.; Knochel, C.; Reinke, B.; Karakaya, T.; Fusser, F.; Pantel, J.

    2014-01-01

    The apolipoprotein E epsilon4 allele is a well established genetic risk factor for sporadic Alzheimer's disease. It is associated with structural and functional brain changes in healthy young, middle-aged and elderly subjects. In the current study, we assessed the impact of the ApoE genotype on brai

  14. The hallucinating brain : A review of structural and functional neuroimaging studies of hallucinations

    NARCIS (Netherlands)

    Allen, Paul; Laroi, Frank; McGuire, Philip K.; Aleman, Andre

    2008-01-01

    Hallucinations remains one of the most intriguing phenomena in psychopathology. In the past two decades the advent of neuroimaging techniques have allowed researchers to investigate what is happening in the brain of those who experience hallucinations. In this article we review both structural and f

  15. Bayesian exponential random graph modeling of whole-brain structural networks across lifespan

    NARCIS (Netherlands)

    Sinke, Michel R T; Dijkhuizen, Rick M; Caimo, Alberto; Stam, Cornelis J; Otte, Wim

    2016-01-01

    Descriptive neural network analyses have provided important insights into the organization of structural and functional networks in the human brain. However, these analyses have limitations for inter-subject or between-group comparisons in which network sizes and edge densities may differ, such as i

  16. Overdiagnosing Vascular Dementia using Structural Brain Imaging for Dementia Work-Up

    NARCIS (Netherlands)

    Niemantsverdriet, Ellis; Feyen, Bart F. E.; Le Bastard, Nathalie; Martin, Jean-Jacques; Goeman, Johan; De Deyn, Peter Paul; Engelborghs, Sebastiaan

    2015-01-01

    Hypothesizing that non-significant cerebrovascular lesions on structural brain imaging lead to overdiagnosis of a vascular etiology of dementia as compared to autopsy-confirmed diagnosis, we set up a study including 71 patients with autopsy-confirmed diagnoses. Forty-two patients in the population (

  17. Progressive gender differences of structural brain networks in healthy adults: a longitudinal, diffusion tensor imaging study.

    Directory of Open Access Journals (Sweden)

    Yu Sun

    Full Text Available Sexual dimorphism in the brain maturation during childhood and adolescence has been repeatedly documented, which may underlie the differences in behaviors and cognitive performance. However, our understanding of how gender modulates the development of structural connectome in healthy adults is still not entirely clear. Here we utilized graph theoretical analysis of longitudinal diffusion tensor imaging data over a five-year period to investigate the progressive gender differences of brain network topology. The brain networks of both genders showed prominent economical "small-world" architecture (high local clustering and short paths between nodes. Additional analysis revealed a more economical "small-world" architecture in females as well as a greater global efficiency in males regardless of scan time point. At the regional level, both increased and decreased efficiency were found across the cerebral cortex for both males and females, indicating a compensation mechanism of cortical network reorganization over time. Furthermore, we found that weighted clustering coefficient exhibited significant gender-time interactions, implying different development trends between males and females. Moreover, several specific brain regions (e.g., insula, superior temporal gyrus, cuneus, putamen, and parahippocampal gyrus exhibited different development trajectories between males and females. Our findings further prove the presence of sexual dimorphism in brain structures that may underlie gender differences in behavioral and cognitive functioning. The sex-specific progress trajectories in brain connectome revealed in this work provide an important foundation to delineate the gender related pathophysiological mechanisms in various neuropsychiatric disorders, which may potentially guide the development of sex-specific treatments for these devastating brain disorders.

  18. Changes in the shape of cloud ice water content vertical structure due to aerosol variations

    Science.gov (United States)

    Massie, Steven T.; Delanoë, Julien; Bardeen, Charles G.; Jiang, Jonathan H.; Huang, Lei

    2016-05-01

    Changes in the shape of cloud ice water content (IWC) vertical structure due to variations in Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depths (AODs), Ozone Monitoring Instrument (OMI) absorptive aerosol optical depths (AAODs), and Microwave Limb Sounder (MLS) CO (an absorptive aerosol proxy) at 215 hPa are calculated in the Tropics during 2007-2010 based upon an analysis of DARDAR IWC profiles for deep convective clouds. DARDAR profiles are a joint retrieval of CloudSat-CALIPSO data. Analysis is performed for 12 separate regions over land and ocean, and carried out applying MODIS AOD fields that attempt to correct for 3-D cloud adjacency effects. The 3-D cloud adjacency effects have a small impact upon our particular calculations of aerosol-cloud indirect effects. IWC profiles are averaged for three AOD bins individually for the 12 regions. The IWC average profiles are also normalized to unity at 5 km altitude in order to study changes in the shape of the average IWC profiles as AOD increases. Derivatives of the IWC average profiles, and derivatives of the IWC shape profiles, in percent change per 0.1 change in MODIS AOD units, are calculated separately for each region. Means of altitude-specific probability distribution functions, which include both ocean and land IWC shape regional derivatives, are modest, near 5 %, and positive to the 2σ level between 11 and 15 km altitude. Similar analyses are carried out for three AAOD and three CO bins. On average, the vertical profiles of the means of the derivatives based upon the profile shapes over land and ocean are smaller for the profiles binned according to AAOD and CO values, than for the MODIS AODs, which include both scattering and absorptive aerosol. This difference in character supports the assertion that absorptive aerosol can inhibit cloud development.

  19. The timing of language learning shapes brain structure associated with articulation.

    Science.gov (United States)

    Berken, Jonathan A; Gracco, Vincent L; Chen, Jen-Kai; Klein, Denise

    2016-09-01

    We compared the brain structure of highly proficient simultaneous (two languages from birth) and sequential (second language after age 5) bilinguals, who differed only in their degree of native-like accent, to determine how the brain develops when a skill is acquired from birth versus later in life. For the simultaneous bilinguals, gray matter density was increased in the left putamen, as well as in the left posterior insula, right dorsolateral prefrontal cortex, and left and right occipital cortex. For the sequential bilinguals, gray matter density was increased in the bilateral premotor cortex. Sequential bilinguals with better accents also showed greater gray matter density in the left putamen, and in several additional brain regions important for sensorimotor integration and speech-motor control. Our findings suggest that second language learning results in enhanced brain structure of specific brain areas, which depends on whether two languages are learned simultaneously or sequentially, and on the extent to which native-like proficiency is acquired. PMID:26420279

  20. ConnectViz: Accelerated Approach for Brain Structural Connectivity Using Delaunay Triangulation.

    Science.gov (United States)

    Adeshina, A M; Hashim, R

    2016-03-01

    Stroke is a cardiovascular disease with high mortality and long-term disability in the world. Normal functioning of the brain is dependent on the adequate supply of oxygen and nutrients to the brain complex network through the blood vessels. Stroke, occasionally a hemorrhagic stroke, ischemia or other blood vessel dysfunctions can affect patients during a cerebrovascular incident. Structurally, the left and the right carotid arteries, and the right and the left vertebral arteries are responsible for supplying blood to the brain, scalp and the face. However, a number of impairment in the function of the frontal lobes may occur as a result of any decrease in the flow of the blood through one of the internal carotid arteries. Such impairment commonly results in numbness, weakness or paralysis. Recently, the concepts of brain's wiring representation, the connectome, was introduced. However, construction and visualization of such brain network requires tremendous computation. Consequently, previously proposed approaches have been identified with common problems of high memory consumption and slow execution. Furthermore, interactivity in the previously proposed frameworks for brain network is also an outstanding issue. This study proposes an accelerated approach for brain connectomic visualization based on graph theory paradigm using compute unified device architecture, extending the previously proposed SurLens Visualization and computer aided hepatocellular carcinoma frameworks. The accelerated brain structural connectivity framework was evaluated with stripped brain datasets from the Department of Surgery, University of North Carolina, Chapel Hill, USA. Significantly, our proposed framework is able to generate and extract points and edges of datasets, displays nodes and edges in the datasets in form of a network and clearly maps data volume to the corresponding brain surface. Moreover, with the framework, surfaces of the dataset were simultaneously displayed with the

  1. ConnectViz: Accelerated Approach for Brain Structural Connectivity Using Delaunay Triangulation.

    Science.gov (United States)

    Adeshina, A M; Hashim, R

    2016-03-01

    Stroke is a cardiovascular disease with high mortality and long-term disability in the world. Normal functioning of the brain is dependent on the adequate supply of oxygen and nutrients to the brain complex network through the blood vessels. Stroke, occasionally a hemorrhagic stroke, ischemia or other blood vessel dysfunctions can affect patients during a cerebrovascular incident. Structurally, the left and the right carotid arteries, and the right and the left vertebral arteries are responsible for supplying blood to the brain, scalp and the face. However, a number of impairment in the function of the frontal lobes may occur as a result of any decrease in the flow of the blood through one of the internal carotid arteries. Such impairment commonly results in numbness, weakness or paralysis. Recently, the concepts of brain's wiring representation, the connectome, was introduced. However, construction and visualization of such brain network requires tremendous computation. Consequently, previously proposed approaches have been identified with common problems of high memory consumption and slow execution. Furthermore, interactivity in the previously proposed frameworks for brain network is also an outstanding issue. This study proposes an accelerated approach for brain connectomic visualization based on graph theory paradigm using compute unified device architecture, extending the previously proposed SurLens Visualization and computer aided hepatocellular carcinoma frameworks. The accelerated brain structural connectivity framework was evaluated with stripped brain datasets from the Department of Surgery, University of North Carolina, Chapel Hill, USA. Significantly, our proposed framework is able to generate and extract points and edges of datasets, displays nodes and edges in the datasets in form of a network and clearly maps data volume to the corresponding brain surface. Moreover, with the framework, surfaces of the dataset were simultaneously displayed with the

  2. Functional and structural brain correlates of risk for major depression in children with familial depression

    OpenAIRE

    Chai, Xiaoqian J.; Dina Hirshfeld-Becker; Joseph Biederman; Mai Uchida; Oliver Doehrmann; Leonard, Julia A.; John Salvatore; Tara Kenworthy; Ariel Brown; Elana Kagan; Carlo de los Angeles; Susan Whitfield-Gabrieli; John D E Gabrieli

    2015-01-01

    Despite growing evidence for atypical amygdala function and structure in major depression, it remains uncertain as to whether these brain differences reflect the clinical state of depression or neurobiological traits that predispose individuals to major depression. We examined function and structure of the amygdala and associated areas in a group of unaffected children of depressed parents (at-risk group) and a group of children of parents without a history of major depression (control group)...

  3. Framingham coronary heart disease risk score can be predicted from structural brain images in elderly subjects.

    Directory of Open Access Journals (Sweden)

    Jane Maryam Rondina

    2014-12-01

    Full Text Available Recent literature has presented evidence that cardiovascular risk factors (CVRF play an important role on cognitive performance in elderly individuals, both those who are asymptomatic and those who suffer from symptoms of neurodegenerative disorders. Findings from studies applying neuroimaging methods have increasingly reinforced such notion. Studies addressing the impact of CVRF on brain anatomy changes have gained increasing importance, as recent papers have reported gray matter loss predominantly in regions traditionally affected in Alzheimer’s disease (AD and vascular dementia in the presence of a high degree of cardiovascular risk. In the present paper, we explore the association between CVRF and brain changes using pattern recognition techniques applied to structural MRI and the Framingham score (a composite measure of cardiovascular risk largely used in epidemiological studies in a sample of healthy elderly individuals. We aim to answer the following questions: Is it possible to decode (i.e., to learn information regarding cardiovascular risk from structural brain images enabling individual predictions? Among clinical measures comprising the Framingham score, are there particular risk factors that stand as more predictable from patterns of brain changes? Our main findings are threefold: i we verified that structural changes in spatially distributed patterns in the brain enable statistically significant prediction of Framingham scores. This result is still significant when controlling for the presence of the APOE 4 allele (an important genetic risk factor for both AD and cardiovascular disease. ii When considering each risk factor singly, we found different levels of correlation between real and predicted factors; however, single factors were not significantly predictable from brain images when considering APOE4 allele presence as covariate. iii We found important gender differences, and the possible causes of that finding are discussed.

  4. Brain structural correlates of reward sensitivity and impulsivity in adolescents with normal and excess weight.

    Directory of Open Access Journals (Sweden)

    Laura Moreno-López

    Full Text Available INTRODUCTION: Neuroscience evidence suggests that adolescent obesity is linked to brain dysfunctions associated with enhanced reward and somatosensory processing and reduced impulse control during food processing. Comparatively less is known about the role of more stable brain structural measures and their link to personality traits and neuropsychological factors on the presentation of adolescent obesity. Here we aimed to investigate regional brain anatomy in adolescents with excess weight vs. lean controls. We also aimed to contrast the associations between brain structure and personality and cognitive measures in both groups. METHODS: Fifty-two adolescents (16 with normal weight and 36 with excess weight were scanned using magnetic resonance imaging and completed the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ, the UPPS-P scale, and the Stroop task. Voxel-based morphometry (VBM was used to assess possible between-group differences in regional gray matter (GM and to measure the putative differences in the way reward and punishment sensitivity, impulsivity and inhibitory control relate to regional GM volumes, which were analyzed using both region of interest (ROI and whole brain analyses. The ROIs included areas involved in reward/somatosensory processing (striatum, somatosensory cortices and motivation/impulse control (hippocampus, prefrontal cortex. RESULTS: Excess weight adolescents showed increased GM volume in the right hippocampus. Voxel-wise volumes of the second somatosensory cortex (SII were correlated with reward sensitivity and positive urgency in lean controls, but this association was missed in excess weight adolescents. Moreover, Stroop performance correlated with dorsolateral prefrontal cortex volumes in controls but not in excess weight adolescents. CONCLUSION: Adolescents with excess weight have structural abnormalities in brain regions associated with somatosensory processing and motivation.

  5. Whole brain expression of bipolar disorder associated genes: structural and genetic analyses.

    Directory of Open Access Journals (Sweden)

    Michael J McCarthy

    Full Text Available Studies of bipolar disorder (BD suggest a genetic basis of the illness that alters brain function and morphology. In recent years, a number of genetic variants associated with BD have been identified. However, little is known about the associated genes, or brain circuits that rely upon their function. Using an anatomically comprehensive survey of the human transcriptome (The Allen Brain Atlas, we mapped the expression of 58 genes with suspected involvement in BD based upon their relationship to SNPs identified in genome wide association studies (GWAS. We then conducted a meta-analysis of structural MRI studies to identify brain regions that are abnormal in BD. Of 58 BD associated genes, 22 had anatomically distinct expression patterns that could be categorized into one of three clusters (C1-C3. Brain regions with the highest and lowest expression of these genes did not overlap strongly with anatomical sites identified as abnormal by structural MRI except in the parahippocampal gyrus, the inferior/superior temporal gyrus and the cerebellar vermis, regions where overlap was significant. Using the 22 genes in C1-C3 as reference points, additional genes with correlated expression patterns were identified and organized into sets based on similarity. Further analysis revealed that five of these gene sets were significantly associated with BD, suggesting that anatomical expression profile is correlated with genetic susceptibility to BD, particularly for genes in C2. Our data suggest that expression profiles of BD-associated genes do not explain the majority of structural abnormalities observed in BD, but may be useful in identifying new candidate genes. Our results highlight the complex neuroanatomical basis of BD, and reinforce illness models that emphasize impaired brain connectivity.

  6. MRI-based brain structure volumes in temporal lobe epilepsy patients and their unaffected siblings: a preliminary study.

    LENUS (Irish Health Repository)

    Scanlon, Cathy

    2013-01-01

    Investigating the heritability of brain structure may be useful in simplifying complicated genetic studies in temporal lobe epilepsy (TLE). A preliminary study is presented to determine if volume deficits of candidate brain structures present at a higher rate in unaffected siblings than controls subjects.

  7. Magnetic resonance imaging quality and volumes of brain structures from live and postmortem imaging of California sea lions with clinical signs of domoic acid toxicosis.

    Science.gov (United States)

    Montie, Eric W; Wheeler, Elizabeth; Pussini, Nicola; Battey, Thomas W K; Barakos, Jerome; Dennison, Sophie; Colegrove, Kathleen; Gulland, Frances

    2010-09-17

    Our goal in this study was to compare magnetic resonance images and volumes of brain structures obtained alive versus postmortem of California sea lions Zalophus californianus exhibiting clinical signs of domoic acid (DA) toxicosis and those exhibiting normal behavior. Proton density-(PD) and T2-weighted images of postmortem-intact brains, up to 48 h after death, provided similar quality to images acquired from live sea lions. Volumes of gray matter (GM) and white matter (WM) of the cerebral hemispheres were similar to volumes calculated from images acquired when the sea lions were alive. However, cerebrospinal fluid (CSF) volumes decreased due to leakage. Hippocampal volumes from postmortem-intact images were useful for diagnosing unilateral and bilateral atrophy, consequences of DA toxicosis. These volumes were similar to the volumes in the live sea lion studies, up to 48 h postmortem. Imaging formalin-fixed brains provided some information on brain structure; however, images of the hippocampus and surrounding structures were of poorer quality compared to the images acquired alive and postmortem-intact. Despite these issues, volumes of cerebral GM and WM, as well as the hippocampus, were similar to volumes calculated from images of live sea lions and sufficient to diagnose hippocampal atrophy. Thus, postmortem MRI scanning (either intact or formalin-fixed) with volumetric analysis can be used to investigate the acute, chronic and possible developmental effects of DA on the brain of California sea lions.

  8. Brain magnetic resonance imaging findings in adult patients with congenital adrenal hyperplasia: Increased frequency of white matter impairment and temporal lobe structures dysgenesis

    Directory of Open Access Journals (Sweden)

    Mouna Feki Mnif

    2013-01-01

    Full Text Available Background: Congenital adrenal hyperplasia (CAH is an inherited recessive disorder of adrenal steroidogenesis. The enzymes most commonly affected are 21-hydroxylase. Past reports suggested brain magnetic resonance imaging (MRI abnormalities in CAH patients, affecting white matter signal, temporal lobe and amygdala structure and function. Aims: In the present study, we aimed to investigate the frequency of white matter changes and temporal lobes structures dysgenesis in a population of patients having CAH due to 21-hydroxylase deficiency. Materials and Methods: Neurological examination and brain MRI were performed in 26 patients. Results: Neurological examination revealed mental retardation in three patients, tremor in two patients, tendon reflexes asymmetry in one patient, and cerebellar syndrome in one patient. Eleven patients (42.3% showed MRI abnormalities: Eight of them had white matter hyperintensities, one patient had moderate atrophy in the right temporal, and hippocampal dysgenesis was found in the remaining two patients. Conclusions: Brain MRI abnormalities in CAH patients include white matter hyperintensities and temporal lobe structures dysgenesis. The mechanisms involved seem related to hormonal imbalances during brain development and exposure to excess exogenous glucocorticoids. Clinical implications of such lesions remain unclear. More extensive studies are required to define better the relationships between brain involvement and different CAH phenotypes and treatment regimens.

  9. Brain activity during interval timing depends on sensory structure.

    Science.gov (United States)

    Pfeuty, Micha; Ragot, Richard; Pouthas, Viviane

    2008-04-14

    Precise timing is crucial for accurate perception and action in the range of hundreds of milliseconds. One still unresolved question concerns the influence of sensory information content on timing mechanisms. Numerous studies have converged to suggest that the CNV (Contingent Negative Variation), a slow negative wave that develops between two events, notably reflects temporal processing of the interval between these two events. The present study aimed at investigating CNV activity in duration discrimination tasks using either filled (continuous tones) or empty intervals (silent periods bounded by two brief tones). Participants had to compare a test duration with a 600-ms standard. Time perception was markedly better in the 'empty' than in the 'filled' condition. Electrophysiological analyses performed on the longest test duration (794 ms) of the comparison phase revealed an effect of the sensory structure on both the CNV amplitude and CNV time-course. The CNV amplitude was larger for filled than for empty intervals, suggesting a superimposition of timing-dependent activity and sensory sustained activity. Furthermore, the CNV time-course paralleled the temporal structure of the memorized sensory event: for filled intervals, the CNV amplitude stopped increasing at 600 ms, i.e. the expected end of the continuous tone; for empty intervals, in contrast, the CNV amplitude precisely increased at 600 ms, i.e. the expected onset of the second brief tone. These results suggest that the CNV reflects the mental rehearsal of the memorized sensory event, in line with the idea that temporal processing in the sub-second range is based on sensory information.

  10. Structural brain network characteristics can differentiate CIS from early RRMS

    Directory of Open Access Journals (Sweden)

    Muthuraman eMuthuraman

    2016-02-01

    Full Text Available Focal demyelinated lesions, diffuse white matter (WM damage and grey matter (GM atrophy influence directly the disease progression in patients with multiple sclerosis. The aim of this study was to identify specific characteristics of GM and WM structural networks in subjects with clinically isolated syndrome (CIS in comparison to patients with early relapsing-remitting multiple sclerosis (RRMS.Twenty patients with CIS, thirty three with RRMS and forty healthy subjects were investigated using 3 T-MRI. Diffusion tensor imaging was applied, together with probabilistic tractography and fractional anisotropy (FA maps for WM and cortical thickness correlation analysis for GM, to determine the structural connectivity patterns. A network topology analysis with the aid of graph theoretical approaches was used to characterize the network at different community levels (modularity, clustering coefficient, global and local efficiencies. Finally, we applied support vector machines (SVM to automatically discriminate the two groups. .In comparison to CIS subjects, patients with RRMS were found to have increased modular connectivity and higher local clustering, highlighting increased local processing in both GM and WM. Both groups presented increased modularity and clustering coefficients in comparison to healthy controls. SVM algorithms achieved 97% accuracy using the clustering coefficient as classifier derived from GM and 65% using WM from probabilistic tractography and 67 % from modularity of FA maps to differentiate between CIS and RRMS patients. We demonstrate a clear increase of modular and local connectivity in patients with early RRMS in comparison to CIS and healthy subjects. Based only on a single anatomic scan and without a priori information, we developed an automated and investigator-independent paradigm that can accurately discriminate between patients with these clinically similar disease entities, and could thus complement the current

  11. Comparative Evaluation for Brain Structural Connectivity Approaches: Towards Integrative Neuroinformatics Tool for Epilepsy Clinical Research.

    Science.gov (United States)

    Yang, Sheng; Tatsuoka, Curtis; Ghosh, Kaushik; Lacuey-Lecumberri, Nuria; Lhatoo, Samden D; Sahoo, Satya S

    2016-01-01

    Recent advances in brain fiber tractography algorithms and diffusion Magnetic Resonance Imaging (MRI) data collection techniques are providing new approaches to study brain white matter connectivity, which play an important role in complex neurological disorders such as epilepsy. Epilepsy affects approximately 50 million persons worldwide and it is often described as a disorder of the cortical network organization. There is growing recognition of the need to better understand the role of brain structural networks in the onset and propagation of seizures in epilepsy using high resolution non-invasive imaging technologies. In this paper, we perform a comparative evaluation of two techniques to compute structural connectivity, namely probabilistic fiber tractography and statistics derived from fractional anisotropy (FA), using diffusion MRI data from a patient with rare case of medically intractable insular epilepsy. The results of our evaluation demonstrate that probabilistic fiber tractography provides a more accurate map of structural connectivity and may help address inherent complexities of neural fiber layout in the brain, such as fiber crossings. This work provides an initial result towards building an integrative informatics tool for neuroscience that can be used to accurately characterize the role of fiber tract connectivity in neurological disorders such as epilepsy. PMID:27570685

  12. Voxel-Based Morphometric Study on Chinese Blind Men's Brain Structure

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-lan; PAN Wen-ju; ZHENG Lian

    2007-01-01

    Many studies have shown the functional relevance of cross-modal plasticity in blind men.In order to study the changes of their brain structure,voxel-based morphometry (VBM) methods are used.The regional gray matter (GM) and white matter (WM) concentrations of magnetic resonance (MR) images from 11 blind people and 9 sighted control subjects are compared using standard VBM.Optimized VBM is also discussed to measure the absolute local volume of GM or WM.Consistent results are achieved by statistical analysis with these methods.There are distinct differences not only in visual cortex but also the sensory area,auditory area and motor area.GM concentrations in blind men significantly decreased in Brodmann 7 and 22.While in Brodmann 18 and 19,GM concentration increased.GM volumes decreased in Brodmann 3,4,6,9 and 45.On the other hand,both WM concentration and volume increased in Brodmann 7.These results suggest that early visual deprivation can lead to changes in the brain structural anatomy which is consistent with the cortical cross-modal reorganization found by functional imaging.It may help to discover the relationship between the brain structural anatomy and the brain functional data of blind men at a macroscopic level from neuroimaging perspective.

  13. Effects of APOE promoter polymorphism on the topological organization of brain structural connectome in nondemented elderly.

    Science.gov (United States)

    Shu, Ni; Li, Xin; Ma, Chao; Zhang, Junying; Chen, Kewei; Liang, Ying; Chen, Yaojing; Zhang, Zhanjun

    2015-12-01

    The polymorphism of the Apolipoprotein E (APOE) promoter rs405509 can regulate the transcriptional activity of the APOE gene and is related to Alzheimer's disease (AD). However, its effects on cognitive performance and the underlying brain mechanisms remain unknown. Here, we performed a battery of neuropsychological tests in a large sample (837 subjects) of nondemented elderly Chinese people, and explored the related brain mechanisms via the construction of diffusion MRI-based structural connectome and graph analysis from a subset (84 subjects) of the sample. Cognitively, the rs405509 risk allele (TT) carriers showed decreased attention and execution functions compared with noncarriers (GG/GT). Regarding the topological alterations of the brain connectome, the risk allele group exhibited reduced global and local efficiency of white matter structural networks, mainly in the left anterior and posterior cingulate cortices (PCC). Importantly, the efficiency of the left PCC is correlated with the impaired attention function and mediates the impacts of the rs405509 genotype on attention. These results demonstrated that the rs405509 polymorphism affects attention function in nondemented elderly people, possibly by modulating brain structural connectivity of the PCC. This polymorphism may help us to understand the neural mechanisms of cognitive aging and to serve as a potential marker assessing the risk of AD.

  14. Uncertainty in soil-structure interaction analysis of a nuclear power plant due to different analytical techniques

    International Nuclear Information System (INIS)

    This paper summarizes the results of the dynamic response analysis of the Zion reactor containment building using three different soil-structure interaction (SSI) analytical procedures which are: the substructure method, CLASSI; the equivalent linear finite element approach, ALUSH; and the nonlinear finite element procedure, DYNA3D. Uncertainties in analyzing a soil-structure system due to SSI analysis procedures were investigated. Responses at selected locations in the structure were compared through peak accelerations and response spectra

  15. Anticipation of monetary and social reward differently activates mesolimbic brain structures in men and women.

    Science.gov (United States)

    Spreckelmeyer, Katja N; Krach, Sören; Kohls, Gregor; Rademacher, Lena; Irmak, Arda; Konrad, Kerstin; Kircher, Tilo; Gründer, Gerhard

    2009-06-01

    Motivation for goal-directed behaviour largely depends on the expected value of the anticipated reward. The aim of the present study was to examine how different levels of reward value are coded in the brain for two common forms of human reward: money and social approval. To account for gender differences 16 male and 16 female participants performed an incentive delay task expecting to win either money or positive social feedback. fMRI recording during the anticipation phase revealed proportional activation of neural structures constituting the human reward system for increasing levels of reward, independent of incentive type. However, in men activation in the prospect of monetary rewards encompassed a wide network of mesolimbic brain regions compared to only limited activation for social rewards. In contrast, in women, anticipation of either incentive type activated identical brain regions. Our findings represent an important step towards a better understanding of motivated behaviour by taking into account individual differences in reward valuation. PMID:19174537

  16. Automated Brain Structure Segmentation Based on Atlas Registration and Appearance Models

    DEFF Research Database (Denmark)

    van der Lijn, Fedde; de Bruijne, Marleen; Klein, Stefan;

    2012-01-01

    Accurate automated brain structure segmentation methods facilitate the analysis of large-scale neuroimaging studies. This work describes a novel method for brain structure segmentation in magnetic resonance images that combines information about a structure’s location and appearance. The spatial...... model is implemented by registering multiple atlas images to the target image and creating a spatial probability map. The structure’s appearance is modeled by a classi¿er based on Gaussian scale-space features. These components are combined with a regularization term in a Bayesian framework...... that is globally optimized using graph cuts. The incorporation of the appearance model enables the method to segment structures with complex intensity distributions and increases its robustness against errors in the spatial model. The method is tested in cross-validation experiments on two datasets acquired...

  17. BrainK for Structural Image Processing: Creating Electrical Models of the Human Head.

    Science.gov (United States)

    Li, Kai; Papademetris, Xenophon; Tucker, Don M

    2016-01-01

    BrainK is a set of automated procedures for characterizing the tissues of the human head from MRI, CT, and photogrammetry images. The tissue segmentation and cortical surface extraction support the primary goal of modeling the propagation of electrical currents through head tissues with a finite difference model (FDM) or finite element model (FEM) created from the BrainK geometries. The electrical head model is necessary for accurate source localization of dense array electroencephalographic (dEEG) measures from head surface electrodes. It is also necessary for accurate targeting of cerebral structures with transcranial current injection from those surface electrodes. BrainK must achieve five major tasks: image segmentation, registration of the MRI, CT, and sensor photogrammetry images, cortical surface reconstruction, dipole tessellation of the cortical surface, and Talairach transformation. We describe the approach to each task, and we compare the accuracies for the key tasks of tissue segmentation and cortical surface extraction in relation to existing research tools (FreeSurfer, FSL, SPM, and BrainVisa). BrainK achieves good accuracy with minimal or no user intervention, it deals well with poor quality MR images and tissue abnormalities, and it provides improved computational efficiency over existing research packages. PMID:27293419

  18. BrainK for Structural Image Processing: Creating Electrical Models of the Human Head

    Directory of Open Access Journals (Sweden)

    Kai Li

    2016-01-01

    Full Text Available BrainK is a set of automated procedures for characterizing the tissues of the human head from MRI, CT, and photogrammetry images. The tissue segmentation and cortical surface extraction support the primary goal of modeling the propagation of electrical currents through head tissues with a finite difference model (FDM or finite element model (FEM created from the BrainK geometries. The electrical head model is necessary for accurate source localization of dense array electroencephalographic (dEEG measures from head surface electrodes. It is also necessary for accurate targeting of cerebral structures with transcranial current injection from those surface electrodes. BrainK must achieve five major tasks: image segmentation, registration of the MRI, CT, and sensor photogrammetry images, cortical surface reconstruction, dipole tessellation of the cortical surface, and Talairach transformation. We describe the approach to each task, and we compare the accuracies for the key tasks of tissue segmentation and cortical surface extraction in relation to existing research tools (FreeSurfer, FSL, SPM, and BrainVisa. BrainK achieves good accuracy with minimal or no user intervention, it deals well with poor quality MR images and tissue abnormalities, and it provides improved computational efficiency over existing research packages.

  19. Graph theoretical analysis of structural and functional connectivity MRI in normal and pathological brain networks.

    Science.gov (United States)

    Guye, Maxime; Bettus, Gaelle; Bartolomei, Fabrice; Cozzone, Patrick J

    2010-12-01

    Graph theoretical analysis of structural and functional connectivity MRI data (ie. diffusion tractography or cortical volume correlation and resting-state or task-related (effective) fMRI, respectively) has provided new measures of human brain organization in vivo. The most striking discovery is that the whole-brain network exhibits "small-world" properties shared with many other complex systems (social, technological, information, biological). This topology allows a high efficiency at different spatial and temporal scale with a very low wiring and energy cost. Its modular organization also allows for a high level of adaptation. In addition, degree distribution of brain networks demonstrates highly connected hubs that are crucial for the whole-network functioning. Many of these hubs have been identified in regions previously defined as belonging to the default-mode network (potentially explaining the high basal metabolism of this network) and the attentional networks. This could explain the crucial role of these hub regions in physiology (task-related fMRI data) as well as in pathophysiology. Indeed, such topological definition provides a reliable framework for predicting behavioral consequences of focal or multifocal lesions such as stroke, tumors or multiple sclerosis. It also brings new insights into a better understanding of pathophysiology of many neurological or psychiatric diseases affecting specific local or global brain networks such as epilepsy, Alzheimer's disease or schizophrenia. Graph theoretical analysis of connectivity MRI data provides an outstanding framework to merge anatomical and functional data in order to better understand brain pathologies. PMID:20349109

  20. Plausible mechanisms for brain structural and size changes in human evolution.

    Science.gov (United States)

    Blazek, Vladimir; Brùzek, Jaroslav; Casanova, Manuel F

    2011-09-01

    Encephalization has many contexts and implications. On one hand, it is concerned with the transformation of eating habits, social relationships and communication, cognitive skills and the mind. Along with the increase in brain size on the other hand, encephalization is connected with the creation of more complex brain structures, namely in the cerebral cortex. It is imperative to inquire into the mechanisms which are linked with brain growth and to find out which of these mechanisms allow it and determine it. There exist a number of theories for understanding human brain evolution which originate from neurological sciences. These theories are the concept of radial units, minicolumns, mirror neurons, and neurocognitive networks. Over the course of evolution, it is evident that a whole range of changes have taken place in regards to heredity. These changes include new mutations of genes in the microcephalin complex, gene duplications, gene co-expression, and genomic imprinting. This complex study of the growth and reorganization of the brain and the functioning of hereditary factors and their external influences creates an opportunity to consider the implications of cultural evolution and cognitive faculties.

  1. The Study on the Durability of Submerged Structure Displacement due to Concrete Failure

    Science.gov (United States)

    Mohd, M.; Zainon, O.; Rasib, A. W.; Majid, Z.

    2016-09-01

    Concrete structures that exposed to marine environments are subjected to multiple deterioration mechanisms. An overview of the existing technology for submerged concrete, pressure resistant, concrete structures which related such as cracks, debonds, and delamination are discussed. Basic knowledge related to drowning durability such as submerged concrete structures in the maritime environment are the durability of a concrete and the ability to resist to weathering, chemical attack, abrasion or other deterioration processes. The measuring techniques and instrumentation for geometrical monitoring of submerged structural displacements have traditionally been categorized into two groups according to the two main groups, namely as geodetic surveying and geotechnical structural measurements of local displacements. This paper aims to study the durability of submerged concrete displacement and harmful effects of submerged concrete structures.

  2. A Multiatlas Approach for Segmenting Subcortical Brain Structures using Local Patch Distance

    Directory of Open Access Journals (Sweden)

    Neela RAMAMOORTHI

    2015-12-01

    Full Text Available In the diagnosis and treatment of various diseases, often segmenting the brain structures from MRI data is the key step. Since there are larger variations in the anatomical structures of the brain, segmentation becomes a crucial process. Using only the intensity information is not enough to segment structures since two or more structures may share the same tissues. Recently, the use of multiple pre-labeled images called atlases or templates are used in the process of segmentation of image data. Both single atlas and multiple atlases can be used. However, using multiple atlases in the segmentation process proves a dominant method in segmenting brain structures with challenging and overlapping structures. In this paper, we propose two multi atlas segmentation methods: Local Patch Distance Segmentation (LPDS and Weighted Local Patch Distance Segmentation (WLPDS. These methods use local patch distance in the label fusion step. LPDS uses local patch distance to find the best patch match for label propagation. WLPDS uses local patch distance to calculate local weights. The brain MRI images from the MICCAI 2012 segmentation challenge are chosen for experimental purposes. These datasets are publicly available and can be downloaded from MIDAS. The proposed techniques are compared with existing fusion methods such as majority voting and weighted majority voting using the similarity measures such as Dice overlap (DC, Jaccard coefficient (JC and Kappa statistics. For 20 test data sets, LPDS gives DICE=0.95±0.05, JACCARD=0.91±0.04 and KAPPA=0.94±0.07. WLPDS gives DICE=0.98±0.02, JACCARD=0.92±0.03 and KAPPA=0.95±0.04.

  3. The effects of physiologically plausible connectivity structure on local and global dynamics in large scale brain models.

    NARCIS (Netherlands)

    Knock, S.A.; McIntosh, A.R.; Sporns, O.; Kotter, R.; Hagmann, P.; Jirsa, V.K.

    2009-01-01

    Functionally relevant large scale brain dynamics operates within the framework imposed by anatomical connectivity and time delays due to finite transmission speeds. To gain insight on the reliability and comparability of large scale brain network simulations, we investigate the effects of variations

  4. Adaptive processing of thin structures to augment segmentation of dual-channel structural MRI of the human brain

    OpenAIRE

    Withers, James

    2010-01-01

    This thesis presents a method for the segmentation of dual-channel structural magnetic resonance imaging (MRI) volumes of the human brain into four tissue classes. The state-of-the-art FSL FAST segmentation software (Zhang et al., 2001) is in widespread clinical use, and so it is considered a benchmark. A significant proportion of FAST’s errors has been shown to be localised to cortical sulci and blood vessels; this issue has driven the developments in this thesis, rather than ...

  5. Symbolic Dynamics and Spiral Structures due to the Saddle-Focus Bifurcations

    Science.gov (United States)

    Shilnikov, Andrey; Shilnikov, Leonid; Barrio, Roberto

    2013-01-01

    We examine spiral structures in bi-parametric diagrams of dissipative systems with strange attractors. We show that the organizing center for spiral structures in the Rössler model with the saddle-focus equilibria is related to the change of the structure of the attractor transitioning between the spiral and screw-like types. The structure skeleton is formed by saddlenode bifurcation curves originating from a codimension-two Belyakov point corresponding to the transition to the saddle-focus from a simple saddle. A new computational technique based on the symbolic kneading invariant description for examining dynamical chaos and parametric chaos in systems with Lorenz-like attractors is proposed and tested. This technique uncovers the stunning complexity and universality of spiral structures in the iconic Lorenz equations.

  6. The cerebrovascular structure and brain tissue volume: a comparative study between beagle dogs and mongrel dogs

    International Nuclear Information System (INIS)

    Objective: To compare the differences of cerebrovascular structure and brain tissue volume between beagle and mongrel dogs by using angiography and MR scanning. Methods: A total of 40 dogs, including 20 beagle dogs (beagle group) and 20 mongrel dogs (mongrel group), were enrolled in this study. Under general anesthesia, all dogs were examined with cerebral angiography and MR scanning. The cerebrovascular structure was evaluated with angiography via selective catheterization of aortic arch, bilateral external cerebral arteries (ECA), maxillary arteries, internal cerebral arteries (ICA) and vertebral arteries separately. The diameters of the ICA, middle cerebral artery (MCA), rostral cerebral artery (RCA), the anastomosis channel ICA and ECA, and basilar artery (BA) were measured at the similar point of each dog. Meanwhile the volumes of the brain tissue were calculated in coronal T2 view of MR scanning. The statistical analysis was performed among the weight of dogs, the diameter of arteries and the volume of brain tissue. The differences in the diameters and brain tissue volume were compared between the two groups. Results: No obvious variations in the cerebrovascular structure and brain tissue volume were found in these dogs. One mongrel dog was excluded from this study because of the severe stenosis of ICA. The mean weight of 20 beagle dogs and 19 mongrel dogs was (12.81±1.29) kg and (12.85±1.12) kg, respectively. The diameters of the ICA, MCA, RCA, the anastomosis channel between ICA and ECA and BA in beagle group were (1.26±0.07) mm, (0.90±0.05) mm, (0.58±0.07) mm, (0.55±0.07) mm and (0.95±0.06) mm, respectively. These parameters in mongrel group were (1.27±0.07) mm, (0.92±0.05) mm, (0.59±0.06) mm, (0.67±0.07) mm and (0.94±0.05) mm, respectively. The volume of brain in two groups was (76232.33±5018.51) mm3 and (71863.96±4626.87) mm3, respectively. There were no obvious correlation among the body weight, the cerebrovascular diameters and brain

  7. Brain Basics

    Medline Plus

    Full Text Available ... Research Modern research tools and techniques are giving scientists a more detailed understanding of the brain than ever before. Brain Imaging Using brain imaging technologies such as magnetic resonance imaging (MRI), which uses magnetic fields to take pictures of the brain's structure, studies ...

  8. Association of social engagement with brain volumes assessed by structural MRI.

    Science.gov (United States)

    James, Bryan D; Glass, Thomas A; Caffo, Brian; Bobb, Jennifer F; Davatzikos, Christos; Yousem, David; Schwartz, Brian S

    2012-01-01

    We tested the hypothesis that social engagement is associated with larger brain volumes in a cohort study of 348 older male former lead manufacturing workers (n = 305) and population-based controls (n = 43), age 48 to 82. Social engagement was measured using a summary scale derived from confirmatory factor analysis. The volumes of 20 regions of interest (ROIs), including total brain, total gray matter (GM), total white matter (WM), each of the four lobar GM and WM, and 9 smaller structures were derived from T1-weighted structural magnetic resonance images. Linear regression models adjusted for age, education, race/ethnicity, intracranial volume, hypertension, diabetes, and control (versus lead worker) status. Higher social engagement was associated with larger total brain and GM volumes, specifically temporal and occipital GM, but was not associated with WM volumes except for corpus callosum. A voxel-wise analysis supported an association in temporal lobe GM. Using longitudinal data to discern temporal relations, change in ROI volumes over five years showed null associations with current social engagement. Findings are consistent with the hypothesis that social engagement preserves brain tissue, and not consistent with the alternate hypothesis that persons with smaller or shrinking volumes become less socially engaged, though this scenario cannot be ruled out.

  9. Association of Social Engagement with Brain Volumes Assessed by Structural MRI

    Directory of Open Access Journals (Sweden)

    Bryan D. James

    2012-01-01

    Full Text Available We tested the hypothesis that social engagement is associated with larger brain volumes in a cohort study of 348 older male former lead manufacturing workers (=305 and population-based controls (=43, age 48 to 82. Social engagement was measured using a summary scale derived from confirmatory factor analysis. The volumes of 20 regions of interest (ROIs, including total brain, total gray matter (GM, total white matter (WM, each of the four lobar GM and WM, and 9 smaller structures were derived from T1-weighted structural magnetic resonance images. Linear regression models adjusted for age, education, race/ethnicity, intracranial volume, hypertension, diabetes, and control (versus lead worker status. Higher social engagement was associated with larger total brain and GM volumes, specifically temporal and occipital GM, but was not associated with WM volumes except for corpus callosum. A voxel-wise analysis supported an association in temporal lobe GM. Using longitudinal data to discern temporal relations, change in ROI volumes over five years showed null associations with current social engagement. Findings are consistent with the hypothesis that social engagement preserves brain tissue, and not consistent with the alternate hypothesis that persons with smaller or shrinking volumes become less socially engaged, though this scenario cannot be ruled out.

  10. Functional and structural brain connectivity of young binge drinkers: a follow-up study.

    Science.gov (United States)

    Correas, A; Cuesta, P; López-Caneda, E; Rodríguez Holguín, S; García-Moreno, L M; Pineda-Pardo, J A; Cadaveira, F; Maestú, F

    2016-01-01

    Adolescence is a period of ongoing brain maturation characterized by hierarchical changes in the functional and structural networks. For this reason, the young brain is particularly vulnerable to the toxic effects of alcohol. Nowadays, binge drinking is a pattern of alcohol consumption increasingly prevalent among adolescents. The aim of the present study is to evaluate the evolution of the functional and anatomical connectivity of the Default Mode Network (DMN) in young binge drinkers along two years. Magnetoencephalography signal during eyes closed resting state as well as Diffusion Tensor Imaging (DTI) were acquired twice within a 2-year interval from 39 undergraduate students (22 controls, 17 binge drinkers) with neither personal nor family history of alcoholism. The group comparison showed that, after maintaining a binge drinking pattern along at least two years, binge drinkers displayed an increased brain connectivity of the DMN in comparison with the control group. On the other hand, the structural connectivity did not show significant differences neither between groups nor over the time. These findings point out that a continued pattern of binge drinking leads to functional alterations in the normal brain maturation process, even before anatomical changes can be detected. PMID:27506835

  11. Her versus his migraine: multiple sex differences in brain function and structure.

    Science.gov (United States)

    Maleki, Nasim; Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David

    2012-08-01

    Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a 'sex phenotype' in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs. PMID:22843414

  12. Functional and structural brain connectivity of young binge drinkers: a follow-up study

    Science.gov (United States)

    Correas, A.; Cuesta, P.; López-Caneda, E.; Rodríguez Holguín, S.; García-Moreno, L. M.; Pineda-Pardo, J. A.; Cadaveira, F.; Maestú, F.

    2016-01-01

    Adolescence is a period of ongoing brain maturation characterized by hierarchical changes in the functional and structural networks. For this reason, the young brain is particularly vulnerable to the toxic effects of alcohol. Nowadays, binge drinking is a pattern of alcohol consumption increasingly prevalent among adolescents. The aim of the present study is to evaluate the evolution of the functional and anatomical connectivity of the Default Mode Network (DMN) in young binge drinkers along two years. Magnetoencephalography signal during eyes closed resting state as well as Diffusion Tensor Imaging (DTI) were acquired twice within a 2-year interval from 39 undergraduate students (22 controls, 17 binge drinkers) with neither personal nor family history of alcoholism. The group comparison showed that, after maintaining a binge drinking pattern along at least two years, binge drinkers displayed an increased brain connectivity of the DMN in comparison with the control group. On the other hand, the structural connectivity did not show significant differences neither between groups nor over the time. These findings point out that a continued pattern of binge drinking leads to functional alterations in the normal brain maturation process, even before anatomical changes can be detected. PMID:27506835

  13. A review on functional and structural brain connectivity in numerical cognition

    Directory of Open Access Journals (Sweden)

    Korbinian eMoeller

    2015-05-01

    Full Text Available Only recently has the complex anatomo-functional system underlying numerical cognition become accessible to evaluation in the living brain. We identified 26 studies investigating brain connectivity in numerical cognition. Despite considerable heterogeneity regarding methodological approaches, populations investigated, and assessment procedures implemented, the results provided largely converging evidence regarding the underlying brain connectivity involved in numerical cognition. Analyses of both functional/effective as well as structural connectivity have consistently corroborated the assumption that numerical cognition is subserved by a fronto-parietal network including (intraparietal as well as (prefrontal cortex sites. Evaluation of structural connectivity has indicated the involvement of fronto-parietal association fibers encompassing the superior longitudinal fasciculus dorsally and the external capsule/extreme capsule system ventrally. Additionally, commissural fibers seem to connect the bilateral intraparietal sulci when number magnitude information is processed. Finally, the identification of projection fibers such as the superior corona radiata indicates connections between cortex and basal ganglia as well as the thalamus in numerical cognition. Studies on functional/effective connectivity further indicated a specific role of the hippocampus. These specifications of brain connectivity augment the triple-code model of number processing and calculation with respect to how grey matter areas associated with specific number-related representations may work together.

  14. Predicting IQ change from brain structure: A cross-validation study

    Science.gov (United States)

    Price, C.J.; Ramsden, S.; Hope, T.M.H.; Friston, K.J.; Seghier, M.L.

    2013-01-01

    Procedures that can predict cognitive abilities from brain imaging data are potentially relevant to educational assessments and studies of functional anatomy in the developing brain. Our aim in this work was to quantify the degree to which IQ change in the teenage years could be predicted from structural brain changes. Two well-known k-fold cross-validation analyses were applied to data acquired from 33 healthy teenagers – each tested at Time 1 and Time 2 with a 3.5 year interval. One approach, a Leave-One-Out procedure, predicted IQ change for each subject on the basis of structural change in a brain region that was identified from all other subjects (i.e., independent data). This approach predicted 53% of verbal IQ change and 14% of performance IQ change. The other approach used half the sample, to identify regions for predicting IQ change in the other half (i.e., a Split half approach); however – unlike the Leave-One-Out procedure – regions identified using half the sample were not significant. We discuss how these out-of-sample estimates compare to in-sample estimates; and draw some recommendations for k-fold cross-validation procedures when dealing with small datasets that are typical in the neuroimaging literature. PMID:23567505

  15. In vitro study on the alterations of brain tubulin structure and assembly affected by magnetite nanoparticles.

    Science.gov (United States)

    Dadras, Ali; Riazi, Gholam Hossein; Afrasiabi, Ali; Naghshineh, Ali; Ghalandari, Behafarid; Mokhtari, Farzad

    2013-03-01

    In recent decades, considerable efforts have been made to understand the mechanism of memory, cognition, and relevant neurodegenerative diseases in the human brain. Several studies have shown the importance of microtubule proteins in the memory mechanism and memory dysfunction. Microtubules possess dynamicity, which is essential for functions of neuronal networks. Microtubule-associated proteins, i.e., tau, play vital roles in microtubule stability. On the other hand, the ferromagnetic mineral magnetite (Fe(3)O(4)) has been detected in the normal human brain, and elevated levels of magnetite are also observed in the brains of Alzheimer's disease patients. Therefore, we propose that a relationship between microtubule organization in axons and brain magnetite nanoparticles is possible. In this study we found alterations of microtubule polymerization in the presence of increasing concentrations of magnetite through transmission electron microscopy images and a turbidimetry method. Structural changes of microtubule and tau protein, as an essential microtubule-associated protein for tubulin assembly, were detected via circular dichroism spectroscopy, intrinsic fluorescence, and 8-anilino-1-naphthalenesulfonic acid fluorometry. We predicted three possible binding sites on tau protein and one possible binding site on tubulin dimer for magnetite nanoparticles. Magnetite also causes the morphology of PC12 cells to change abnormally and cell viability to decrease. Finally, we suggest that magnetite changes microtubule dynamics and polymerization through two paths: (1) changing the secondary and tertiary structure of tubulin and (2) binding to either tubulin dimer or tau protein and preventing tau-tubulin interaction.

  16. Cognitive function and brain structure after recurrent mild traumatic brain injuries in young-to-middle-aged adults

    Directory of Open Access Journals (Sweden)

    Jonathan eList

    2015-05-01

    Full Text Available Recurrent mild traumatic brain injuries (mTBIs are regarded as an independent risk factor for developing dementia in later life. We here aimed to evaluate associations between recurrent mTBIs, cognition, and grey matter volume and microstructure as revealed by structural magnetic resonance imaging (MRI in the chronic phase after mTBIs in young adulthood. We enrolled 20 young-to-middle-aged subjects, who reported two or more sports-related mTBIs, with the last mTBI>6 months prior to study enrolment (mTBI group, and 21 age-, sex- and education matched controls with no history of mTBI (control group. All participants received comprehensive neuropsychological testing, and high resolution T1-weighted and diffusion tensor MRI in order to assess cortical thickness (CT and microstructure, hippocampal volume, and ventricle size. Compared to the control group, subjects of the mTBI group presented with lower CT within the right temporal lobe and left insula using an a priori region of interest approach. Higher number of mTBIs was associated with lower CT in bilateral insula, right middle temporal gyrus and right entorhinal area. Our results suggest persistent detrimental effects of recurrent mTBIs on CT already in young-to-middle-aged adults. If additional structural deterioration occurs during aging, subtle neuropsychological decline may progress to clinically overt dementia earlier than in age-matched controls, a hypothesis to be assessed in future prospective trials.

  17. Cognitive function and brain structure after recurrent mild traumatic brain injuries in young-to-middle-aged adults

    Science.gov (United States)

    List, Jonathan; Ott, Stefanie; Bukowski, Martin; Lindenberg, Robert; Flöel, Agnes

    2015-01-01

    Recurrent mild traumatic brain injuries (mTBIs) are regarded as an independent risk factor for developing dementia in later life. We here aimed to evaluate associations between recurrent mTBIs, cognition, and gray matter volume and microstructure as revealed by structural magnetic resonance imaging (MRI) in the chronic phase after mTBIs in young adulthood. We enrolled 20 young-to-middle-aged subjects, who reported two or more sports-related mTBIs, with the last mTBI > 6 months prior to study enrolment (mTBI group), and 21 age-, sex- and education matched controls with no history of mTBI (control group). All participants received comprehensive neuropsychological testing, and high resolution T1-weighted and diffusion tensor MRI in order to assess cortical thickness (CT) and microstructure, hippocampal volume, and ventricle size. Compared to the control group, subjects of the mTBI group presented with lower CT within the right temporal lobe and left insula using an a priori region of interest approach. Higher number of mTBIs was associated with lower CT in bilateral insula, right middle temporal gyrus and right entorhinal area. Our results suggest persistent detrimental effects of recurrent mTBIs on CT already in young-to-middle-aged adults. If additional structural deterioration occurs during aging, subtle neuropsychological decline may progress to clinically overt dementia earlier than in age-matched controls, a hypothesis to be assessed in future prospective trials. PMID:26052275

  18. Neuromelanins of human brain have soluble and insoluble components with dolichols attached to the melanic structure.

    Directory of Open Access Journals (Sweden)

    Mireille Engelen

    Full Text Available Neuromelanins (NMs are neuronal pigments of melanic-lipidic type which accumulate during aging. They are involved in protective and degenerative mechanisms depending on the cellular context, however their structures are still poorly understood. NMs from nine human brain areas were analyzed in detail. Elemental analysis led to identification of three types of NM, while infrared spectroscopy showed that NMs from neurons of substantia nigra and locus coeruleus, which selectively degenerate in Parkinson's disease, have similar structure but different from NMs from brain regions not targeted by the disease. Synthetic melanins containing Fe and bovine serum albumin were prepared to model the natural product and help clarifying the structure of NMs. Extensive nuclear magnetic resonance spectroscopy studies showed the presence of dolichols both in the soluble and insoluble parts of NM. Diffusion measurements demonstrated that the dimethyl sulfoxide soluble components consist of oligomeric precursors with MWs in the range 1.4-52 kDa, while the insoluble part contains polymers of larger size but with a similar composition. These data suggest that the selective vulnerability of neurons of substantia nigra and locus coeruleus in Parkinson's disease might depend on the structure of the pigment. Moreover, they allow to propose a pathway for NM biosynthesis in human brain.

  19. The application of a mathematical model linking structural and functional connectomes in severe brain injury

    Directory of Open Access Journals (Sweden)

    A. Kuceyeski

    2016-01-01

    Full Text Available Following severe injuries that result in disorders of consciousness, recovery can occur over many months or years post-injury. While post-injury synaptogenesis, axonal sprouting and functional reorganization are known to occur, the network-level processes underlying recovery are poorly understood. Here, we test a network-level functional rerouting hypothesis in recovery of patients with disorders of consciousness following severe brain injury. This hypothesis states that the brain recovers from injury by restoring normal functional connections via alternate structural pathways that circumvent impaired white matter connections. The so-called network diffusion model, which relates an individual's structural and functional connectomes by assuming that functional activation diffuses along structural pathways, is used here to capture this functional rerouting. We jointly examined functional and structural connectomes extracted from MRIs of 12 healthy and 16 brain-injured subjects. Connectome properties were quantified via graph theoretic measures and network diffusion model parameters. While a few graph metrics showed groupwise differences, they did not correlate with patients' level of consciousness as measured by the Coma Recovery Scale — Revised. There was, however, a strong and significant partial Pearson's correlation (accounting for age and years post-injury between level of consciousness and network diffusion model propagation time (r = 0.76, p < 0.05, corrected, i.e. the time functional activation spends traversing the structural network. We concluded that functional rerouting via alternate (and less efficient pathways leads to increases in network diffusion model propagation time. Simulations of injury and recovery in healthy connectomes confirmed these results. This work establishes the feasibility for using the network diffusion model to capture network-level mechanisms in recovery of consciousness after severe brain injury.

  20. Changes in a coke structure due to reaction with carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Pusz, S.; Majewska, J.; Pilawa, B. [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, PL-41819 Zabrze (Poland); Krzesinska, M. [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Sklodowskiej 34, PL-41819 Zabrze (Poland); Silesian Technical University, Department of Electron Technology, Institute of Physics, Krzywoustego 2, PL-44100 Gliwice (Poland); Smedowski, L. [Silesian Technical University, Department of Electron Technology, Institute of Physics, Krzywoustego 2, PL-44100 Gliwice (Poland); Kwiecinska, B. [AGH-University of Science and Technology, Aleja Mickiewicza 30, PL-30059 Krakow (Poland)

    2010-04-01

    Technological properties of a coke directly depend on a coke structure, i.e., on carbon matrix (a solid phase in a porous medium) and on pore system. Coke structure is deeply transformed during blast furnace operation and one of the most important factors responsible for that is the CO{sub 2} gasification. The objective of this work was to investigate changes of the physical structure of a coke upon the reaction with carbon dioxide to evaluate the effects of structural transformations on technological properties of a coke. Selected physical parameters of cokes produced in a laboratory scale were carried out prior to and after the reaction with CO{sub 2}. The following physical methods were used for the study: helium gas densitometry, physical adsorption of N{sub 2}, optical microscopy, transmission electron microscopy (TEM), ultrasonic measurements and electron paramagnetic resonance spectroscopy (EPR). The results showed that the reaction with CO{sub 2} distinctly affects the physical structure of coke. Coke solid matrix becomes better ordered, with greater structural units, while development of pore structure consists in the enlargement and coalescence of pores and the increase of specific surface area. Great increase of coke porosity after the reaction with CO{sub 2} seems to be more affecting the final strength and reactivity of coke than the transformation of carbon matrix. (author)

  1. Cardiac arrest due to intracranial hypotension following pseudohypoxic brain swelling induced by negative suction drainage in a cranioplasty patient: a case report

    OpenAIRE

    Moon, Hyun-Soo; Lee, Soo Kyung; Kim, Su Ryun; Kim, Seon Ju

    2016-01-01

    Pseudohypoxic brain swelling (PHBS) is known to be an uncommon event that may occur during and following an uneventful brain surgery, when negative suction drainage is used. The cerebrospinal fluid loss related to suction drainage can evoke intracranial hypotension that progress to PHBS. The main presentations of PHBS are sudden unexpected circulatory collapses, such as severe bradycardia, hypotension, cardiac arrest, consciousness deterioration and diffuse brain swelling as seen with brain c...

  2. Brain structure-function associations in multi-generational families genetically enriched for bipolar disorder.

    Science.gov (United States)

    Fears, Scott C; Schür, Remmelt; Sjouwerman, Rachel; Service, Susan K; Araya, Carmen; Araya, Xinia; Bejarano, Julio; Knowles, Emma; Gomez-Makhinson, Juliana; Lopez, Maria C; Aldana, Ileana; Teshiba, Terri M; Abaryan, Zvart; Al-Sharif, Noor B; Navarro, Linda; Tishler, Todd A; Altshuler, Lori; Bartzokis, George; Escobar, Javier I; Glahn, David C; Thompson, Paul M; Lopez-Jaramillo, Carlos; Macaya, Gabriel; Molina, Julio; Reus, Victor I; Sabatti, Chiara; Cantor, Rita M; Freimer, Nelson B; Bearden, Carrie E

    2015-07-01

    Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain-behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain-behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18-87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain-behaviour associations and test whether brain-behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain-behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non-bipolar disorder family

  3. Quantitative MRI of the spinal cord and brain in adrenomyeloneuropathy: in vivo assessment of structural changes.

    Science.gov (United States)

    Castellano, Antonella; Papinutto, Nico; Cadioli, Marcello; Brugnara, Gianluca; Iadanza, Antonella; Scigliuolo, Graziana; Pareyson, Davide; Uziel, Graziella; Köhler, Wolfgang; Aubourg, Patrick; Falini, Andrea; Henry, Roland G; Politi, Letterio S; Salsano, Ettore

    2016-06-01

    Adrenomyeloneuropathy is the late-onset form of X-linked adrenoleukodystrophy, and is considered the most frequent metabolic hereditary spastic paraplegia. In adrenomyeloneuropathy the spinal cord is the main site of pathology. Differently from quantitative magnetic resonance imaging of the brain, little is known about the feasibility and utility of advanced neuroimaging in quantifying the spinal cord abnormalities in hereditary diseases. Moreover, little is known about the subtle pathological changes that can characterize the brain of adrenomyeloneuropathy subjects in the early stages of the disease. We performed a cross-sectional study on 13 patients with adrenomyeloneuropathy and 12 age-matched healthy control subjects who underwent quantitative magnetic resonance imaging to assess the structural changes of the upper spinal cord and brain. Total cord areas from C2-3 to T2-3 level were measured, and diffusion tensor imaging metrics, i.e. fractional anisotropy, mean, axial and radial diffusivity values were calculated in both grey and white matter of spinal cord. In the brain, grey matter regions were parcellated with Freesurfer and average volume and thickness, and mean diffusivity and fractional anisotropy from co-registered diffusion maps were calculated in each region. Brain white matter diffusion tensor imaging metrics were assessed using whole-brain tract-based spatial statistics, and tractography-based analysis on corticospinal tracts. Correlations among clinical, structural and diffusion tensor imaging measures were calculated. In patients total cord area was reduced by 26.3% to 40.2% at all tested levels (P statistics showed a marked reduction of fractional anisotropy, increase of radial diffusivity (P < 0.001) and no axial diffusivity changes in several white matter tracts, including corticospinal tracts and optic radiations, indicating predominant demyelination. Tractography-based analysis confirmed the results within corticospinal tracts. No

  4. 3D segmentation of rodent brain structures using hierarchical shape priors and deformable models.

    Science.gov (United States)

    Zhang, Shaoting; Huang, Junzhou; Uzunbas, Mustafa; Shen, Tian; Delis, Foteini; Huang, Xiaolei; Volkow, Nora; Thanos, Panayotis; Metaxas, Dimitris N

    2011-01-01

    In this paper, we propose a method to segment multiple rodent brain structures simultaneously. This method combines deformable models and hierarchical shape priors within one framework. The deformation module employs both gradient and appearance information to generate image forces to deform the shape. The shape prior module uses Principal Component Analysis to hierarchically model the multiple structures at both global and local levels. At the global level, the statistics of relative positions among different structures are modeled. At the local level, the shape statistics within each structure is learned from training samples. Our segmentation method adaptively employs both priors to constrain the intermediate deformation result. This prior constraint improves the robustness of the model and benefits the segmentation accuracy. Another merit of our prior module is that the size of the training data can be small, because the shape prior module models each structure individually and combines them using global statistics. This scheme can preserve shape details better than directly applying PCA on all structures. We use this method to segment rodent brain structures, such as the cerebellum, the left and right striatum, and the left and right hippocampus. The experiments show that our method works effectively and this hierarchical prior improves the segmentation performance. PMID:22003750

  5. Brain structure in diving players on MR imaging studied with voxel-based morphometry

    Institute of Scientific and Technical Information of China (English)

    Gaoxia Wei; Jing Luo; Youfa Li

    2009-01-01

    We adopted professional diving players as a typical subject pool to explore whether structural brain differences relative to motor skill acquisition exist between highly skilled athletes and non-athletes. Based on the voxel-based morphometric (VBM) technique, structural MRIs of the brains of 12 elite diving players with professional training were analyzed and compared with those of control subjects with-out any professional physical training. Diving players showed significantly increased gray matter density in the thalamus and left pre-central gyrus than control subjects. However, future researches are needed to prove the contribution of preposition and practice. It also suggests that athletes as the subject pool could form a new subject pool to explore plastic change induced by motor skill acquisition.

  6. The effect of alcohol use on human adolescent brain structures and systems.

    Science.gov (United States)

    Squeglia, Lindsay M; Jacobus, Joanna; Tapert, Susan F

    2014-01-01

    This article reviews the neurocognitive and neuroimaging literature regarding the effect of alcohol use on human adolescent brain structure and function. Adolescents who engage in heavy alcohol use, even at subdiagnostic levels, show differences in brain structure, function, and behavior when compared with non-drinking controls. Preliminary longitudinal studies have helped disentangle premorbid factors from consequences associated with drinking. Neural abnormalities and cognitive disadvantages both appear to predate drinking, particularly in youth who have a family history of alcoholism, and are directly related to the neurotoxic effect of alcohol use. Binge drinking and withdrawal and hangover symptoms have been associated with the greatest neural abnormalities during adolescence, particularly in frontal, parietal, and temporal regions. PMID:25307592

  7. Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia

    DEFF Research Database (Denmark)

    Hammer, Trine B; Oranje, Bob; Skimminge, Arnold;

    2013-01-01

    with schizophrenia and healthy controls; however, these studies included only patients with chronic illness and medicated patients. Our aim was to examine the structural brain correlates of PPI in antipsychotic-naive patients with first-episode schizophrenia. Methods: We performed acoustic PPI assessment...... and structural MRI (1.5 and 3 T) in men with first-episode schizophrenia and age-matched controls. Voxel-based morphometry was used to investigate the association between PPI and grey matter volumes. Results: We included 27 patients and 38 controls in the study. Patients had lower PPI than controls. The brain...... areas in which PPI and grey matter volume correlated did not differ between the groups. Independent of group, PPI was significantly and positively associated with regional grey matter volume in the right superior parietal cortex. Prepulse inhibition and grey matter volume associations were also observed...

  8. Adverse associations between visceral adiposity, brain structure and cognitive performance in healthy elderly

    Directory of Open Access Journals (Sweden)

    Vivian eIsaac

    2011-09-01

    Full Text Available The link between central adiposity and cognition has been established by indirect measures such as BMI or waist-hip ratio. Magnetic resonance imaging (MRI quantification of central abdominal fat has been linked to elevated risk of cardio-vascular and cerebro-vascular disease. However it is not known how quantification of visceral fat correlates with cognitive performance and measures of brain structure. We filled this gap by characterizing the relationships between MRI measures of abdominal adiposity, brain morphometry and cognition, in healthy elderly. Methods: A total of 184 healthy community dwelling elderly subjects without cognitive impairment participated in this study. Anthropometric and biochemical markers of cardio-vascular risk, neuropsychological measurements as well as MRI of the brain and abdomen fat were obtained. Abdominal images were segmented into subcutaneous (SAT and visceral (VAT adipose tissue compartments. Brain MRI measures were analyzed quantitatively to determine total brain volume, hippocampal volume, ventricular volume and cortical thickness. Results: VAT showed negative association with verbal memory (r=0.21, p=0.005 and attention (r=0.18, p=0.01. Higher VAT was associated with lower hippocampal volume (F=5.39, p=0.02 and larger ventricular volume (F=6.07, p=0.02. The participants in the upper quartile of VAT had the lowest hippocampal volume even after adjusting for age, gender, hypertension and BMI (b=-0.28, p=0.005. There was a significant age by VAT interaction for cortical thickness in the left prefrontal region. Conclusions: In healthy older adults, elevated VAT is associated with negative effects on cognition, and brain morphometry.

  9. Topographic congruence of calcified parenchymal neurocysticercosis and other structural brain lesions with epileptiform activity

    Science.gov (United States)

    Saito, Erin K; Nagpal, Meera; Leon, Amanda; Mehta, Bijal; McMurtray, Aaron Matthew

    2016-01-01

    Introduction: Calcified parenchymal neurocysticercosis (NCC) lesions are commonly detected in many individuals with refractory epilepsy. However, the relationship between these lesions and epilepsy is not fully determined. We sought to determine if calcified parenchymal NCC demonstrated topographic congruence with epileptiform activity in refractory epilepsy patients. Additional patients with other structural brain lesions were included for comparison. Subjects and Methods: Retrospective cross-sectional analysis of all patients treated at a community-based neurology clinic for refractory epilepsy during a 3-month period and with structural brain lesions detected by neuroimaging studies. Results: A total of 105 patients were included in the study, including 63 with calcified parenchymal NCC lesions and 42 with other structural brain lesions. No significant relationship was detected between hemispheric localization of calcified parenchymal NCC lesions and epileptiform activity. For those with other structural brain lesions, the hemispheric localization was significantly related to the side of epileptiform activity (Chi-square = 11.13, P = 0.025). In addition, logistic regression models showed that those with right-sided non-NCC lesions were more likely to have right-sided epileptiform activity (odds ratio = 4.36, 95% confidence interval [CI] =1.16–16.31, P = 0.029), and those with left-sided non-NCC lesions were more likely to have left-sided epileptiform activity (odds ratio = 7.60, 95% CI = 1.89–30.49, P = 0.004). Conclusion: The lack of correlation between the side of calcified parenchymal NCC lesions and the side of the epileptiform activity suggests that these lesions may be incidental findings in many patients. PMID:26998434

  10. The Self-Liking Brain: A VBM Study on the Structural Substrate of Self-Esteem

    OpenAIRE

    Dmitrij Agroskin; Johannes Klackl; Eva Jonas

    2014-01-01

    Abundant evidence suggests that self-esteem is an important personality resource for emotion regulation in response to stressful experiences. It was thus hypothesized that the relative grey matter volume of brain regions involved in responding to and coping with stress is related to individual differences in trait self-esteem. Using structural magnetic resonance imaging of 48 healthy adults in conjunction with voxel-based morphometry and diffeomorphic anatomical registration using exponentiat...

  11. Her versus his migraine: multiple sex differences in brain function and structure

    OpenAIRE

    Maleki, Nasim; Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David

    2012-01-01

    Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional response...

  12. Brain structure and joint hypermobility: relevance to the expression of psychiatric symptoms

    OpenAIRE

    Jessica A Eccles; Beacher, Felix D. C.; Gray, Marcus A.; Jones, Catherine L.; Minati, Ludovico; Harrison, Neil A.; Hugo D. Critchley

    2012-01-01

    Joint hypermobility is overrepresented among people with anxiety and can be associated with abnormal autonomic reactivity. We tested for associations between regional cerebral grey matter and hypermobility in 72 healthy volunteers using voxel-based morphometry of structural brain scans. Strikingly, bilateral amygdala volume distinguished those with from those without hypermobility. The hypermobility group scored higher for interoceptive sensitivity yet were not significantly more anxious. Our...

  13. Focus on: Structural and Functional Brain Abnormalities in Fetal Alcohol Spectrum Disorders

    OpenAIRE

    Nuñez, S. Christopher; Roussotte, Florence; Sowell, Elizabeth R.

    2011-01-01

    Children exposed to alcohol prenatally can experience significant deficits in cognitive and psychosocial functioning as well as alterations in brain structure and function related to alcohol’s teratogenic effects. These impairments are present both in children with fetal alcohol syndrome (FAS) and in children with heavy in utero alcohol exposure who do not have facial dysmorphology required for the FAS diagnosis. Neuropsychological and behavioral studies have revealed deficits in most cogniti...

  14. Use of the Structure of Blood Vessel for Detection of Brain Aneurysm and Route Search to Brain Aneurysm

    Directory of Open Access Journals (Sweden)

    Toshihide Miyagi

    2013-08-01

    Full Text Available In this research, we constructed functions that are necessary for the operation simulation system which assists medical students to inhibit brain aneurysm from exploding. The system reported in this paper is "detection of blood vessels", "detection of brain aneurysm" and "route planning to brain aneurysm". Not only the detection method but also the method to reduce the miss detection is realized for the detection of blood vessel. Finally, the future work will be shown including construction of head model consisting of artery, vein, brain and cranium.

  15. Study of the effects of corrugated wall structures due to blanket modules around ICRH antennas

    Energy Technology Data Exchange (ETDEWEB)

    Dumortier, Pierre; Louche, Fabrice; Messiaen, André; Vervier, Michel [LPP-ERM/KMS, EURATOM-Belgian State Association, TEC partner, B-1000 Brussels (Belgium)

    2014-02-12

    In future fusion reactors, and in ITER, the first wall will be covered by blanket modules. These blanket modules, whose dimensions are of the order of the ICRF wavelengths, together with the clearance gaps between them will constitute a corrugated structure which will interact with the electromagnetic waves launched by ICRF antennas. The conditions in which the grooves constituted by the clearance gaps between the blanket modules can become resonant are studied. Simple analytical models and numerical simulations show that mushroom type structures (with larger gaps at the back than at the front) can bring down the resonance frequencies, which could lead to large voltages in the gaps between the blanket modules and perturb the RF properties of the antenna if they are in the ICRF operating range. The effect on the wave propagation along the wall structure, which is acting as a spatially periodic (toroidally and poloidally) corrugated structure, and hence constitutes a slow wave structure modifying the wall boundary condition, is examined.

  16. Numerical simulations of dynamic response of narrow conical structures due to ice actions

    Energy Technology Data Exchange (ETDEWEB)

    Dalane, O.; Loset, S. [Norwegian Univ. of Science and Technology, Trondheim (Norway); Xu, N.; Yue, Q. [Dalian Univ. of Technology, Dalian (China); Tuomo, K. [Norwegian Univ. of Science and Technology, Trondheim (Norway)]|[Karna Research and Consulting, Helsinki (Finland)

    2008-07-01

    The design of an offshore drilling platform in the Bohai Bay of North China was recently modified in an effort to reduce vibrations resulting from ice action. This paper presented a theoretical example where a conical structure was exposed to sheet ice action. The dynamic analysis for the structure was based on a narrow cone where rubble build-up does not influence the ice action. Both field data and recent theoretical studies showed that the time-varying ice action and the structural response constitute a narrow-band random process under these conditions. According to structural dynamic studies, the time of exposure can be a significant parameter if the response has a narrow-band character. The numerical simulation is influenced by such ice action since there is a possibility that the real response will be underestimated if the time of a numerical simulation is not sufficiently long. This paper addressed this problem by using a numerical method based on data obtained from full-scale structures deployed in the Bohai Bay. The purpose was to determine the time required to reach a maximum response while the key parameters of the load model vary randomly. The simulation results were compared with a similar analysis performed on full-scale data. 21 refs., 11 figs.

  17. Revealing pathologies in the liquid crystalline structures of the brain by polarimetric studies (Presentation Recording)

    Science.gov (United States)

    Bakhshetyan, Karen; Melkonyan, Gurgen G.; Galstian, Tigran V.; Saghatelyan, Armen

    2015-10-01

    Natural or "self" alignment of molecular complexes in living tissue represents many similarities with liquid crystals (LC), which are anisotropic liquids. The orientational characteristics of those complexes may be related to many important functional parameters and their study may reveal important pathologies. The know-how, accumulated thanks to the study of LC materials, may thus be used to this end. One of the traditionally used methods, to characterize those materials, is the polarized light imaging (PLI) that allows for label-free analysis of anisotropic structures in the brain tissue and can be used, for example, for the analysis of myelinated fiber bundles. In the current work, we first attempted to apply the PLI on the mouse histological brain sections to create a map of anisotropic structures using cross-polarizer transmission light. Then we implemented the PLI for comparative study of histological sections of human postmortem brain samples under normal and pathological conditions, such as Parkinson's disease (PD). Imaging the coronal, sagittal and horizontal sections of mouse brain allowed us to create a false color-coded fiber orientation map under polarized light. In human brain datasets for both control and PD groups we measured the pixel intensities in myelin-rich subregions of internal capsule and normalized these to non-myelinated background signal from putamen and caudate nucleus. Quantification of intensities revealed a statistically significant reduction of fiber intensity of PD compared to control subjects (2.801 +/- 0.303 and 3.724 +/- 0.07 respectively; *p < 0.05). Our study confirms the validity of PLI method for visualizing myelinated axonal fibers. This relatively simple technique can become a promising tool for study of neurodegenerative diseases where labeling-free imaging is an important benefit.

  18. Specific Properties of Single-Wall Carbon Nanohorns Due to Unique Structure

    Science.gov (United States)

    Yudasaka, M.; Nisha, J. A.; Kauya, D.; Kokai, F.; Takahashi, K.; Hirahara, K.; Iijima, S.

    2001-03-01

    Single-wall carbon nanohorns (SWNHs), 30-50 nm long and 2-3 nm thick, form aggregates that resemble dahlia flowers (DF-SWNHs) (diameter: 80 nm). CO2 laser vaporization of graphite at room temperature produced a high yield (about 75several interesting electromagnetic phenomena. The large surface area and micropores are useful for adsorbing other materials. For instance, DF-SWNHs adsorbed ethanol about three times more efficiently than conventional activated carbon. For further applications, we modified their structure by oxidation in oxygen gas. The structural change was obvious in TGA and the Raman spectrum, and TEM showed the holes that were created. This structural change varied the gas adsorption properties [3]. [1] S. Iijima et al., Chem. Phys. Lett., 309 (1999) 165. [2] J. A. Nisha et al., Chem. Phys. Lett., 328 (2000) 381. [3] K. Murata et al. this conference.

  19. Internal Force Analysis Due to the Supporting Translation in Statically Indeterminate Structures for Different Elastic Modulus

    Institute of Scientific and Technical Information of China (English)

    姚文娟; 叶志明

    2004-01-01

    For statically indeterminate structure, the internal force will be changed with the translation of the supports, because the internal force is related to the absolute value of the stiffness EI. When the tension is different with the compression modulus, EI is the function of internal force and is not constant any more that is different from classic mechanics. In the other words, it is a nonlinear problem to calculate the internal force. The expression for neutral axis of the statically indeterminate structure was derived in the paper. The iterative program for nonlinear internal force was compiled. One case study was presented to illustrate the difference between the results using the different modulus theory and the single modulus theory as in classical mechanics. Finally, some reasonable suggestions were made for the different modulus structures.

  20. Structure of a scheme of emergency control to avoid blackout due to interconnection lines loss

    Energy Technology Data Exchange (ETDEWEB)

    Luz, L.T. da; Werberich, L.C.; Herve, H.M. [Companhia Estadual de Energia Eletrica do Estado do Rio Grande do Sul (CEEE), Porto Alegre, RS (Brazil)

    1994-12-31

    This work presents the structure of Gravatai Emergency Control Scheme (ECS) with short about its development and operation. This ECS was made to avoid two kinds of problems for the systems of Companhia Estadual de Energia Eletrica (CEEE). The first one is the voltage collapse that happens after the opening of one of the 525 kv LTs of the interconnection with the Brazilian Interconnected System (BIS). The second one is the CEEE isolating after the 525 kV network loss. We show the ECS existence reason and we describe its functional structure, the substations, the circuits and the amount of load shedding involved by the system. Finally, we present the project of a control structure based on microcomputer which is being developed for this ECS. (author) 3 refs., 11 figs.

  1. Sorbent Structural Impacts Due to Humidity on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    Science.gov (United States)

    Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard

    2015-01-01

    The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.

  2. Analysis of Various Automated Structural Computing Methods Inpatient with Early Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Neeraj Upadhyay

    2015-02-01

    Full Text Available Aim: To assess Surface Based Morphometry (SBM and Voxel Based Morphometry (VBM, the automated computation methods to demonstrate volume and thickness changes in brain among early Traumatic Brain Injury (TBI and their correlation with cognitive test scores. Methods: 22 mild to moderate TBI patients and 20 age, gender matched healthy individuals were recruited (mean ± SD, age range: 27.7 ± 6.5 years. MRI scans were acquired in the Siemens 3T Magnetom Skyra Scanner. TheT1-weighted magnetization preparation rapid acquisition gradient echo (MP-RAGE sequence used for morphometric analysis provided excellent gray-white matter contrast. The structural data was processed using SBM and VBM methods with statistical significance of P<0.05 corrected for multiple comparisons. Results: both methods did not show any significant changes in brain measures after correcting for false discovery rate. However, on correlating neuropsychological score with structural changes, SBM demonstrated significant voxels survived in animal naming and Token Test after correcting for multiple comparisons. No significant change was found while using VBM. Conclusion: The study emphasizes the similarities in the results obtained after using different automatedmethods. Our findings suggest that SBM is more sensitive as compared to VBM in detecting structural changes correlated with Neuropsychological scores during early phase of TBI.

  3. Brain structural alterations in obsessive-compulsive disorder patients with autogenous and reactive obsessions.

    Directory of Open Access Journals (Sweden)

    Marta Subirà

    Full Text Available Obsessive-compulsive disorder (OCD is a clinically heterogeneous condition. Although structural brain alterations have been consistently reported in OCD, their interaction with particular clinical subtypes deserves further examination. Among other approaches, a two-group classification in patients with autogenous and reactive obsessions has been proposed. The purpose of the present study was to assess, by means of a voxel-based morphometry analysis, the putative brain structural correlates of this classification scheme in OCD patients. Ninety-five OCD patients and 95 healthy controls were recruited. Patients were divided into autogenous (n = 30 and reactive (n = 65 sub-groups. A structural magnetic resonance image was acquired for each participant and pre-processed with SPM8 software to obtain a volume-modulated gray matter map. Whole-brain and voxel-wise comparisons between the study groups were then performed. In comparison to the autogenous group, reactive patients showed larger gray matter volumes in the right Rolandic operculum. When compared to healthy controls, reactive patients showed larger volumes in the putamen (bilaterally, while autogenous patients showed a smaller left anterior temporal lobe. Also in comparison to healthy controls, the right middle temporal gyrus was smaller in both patient subgroups. Our results suggest that autogenous and reactive obsessions depend on partially dissimilar neural substrates. Our findings provide some neurobiological support for this classification scheme and contribute to unraveling the neurobiological basis of clinical heterogeneity in OCD.

  4. Relating Education, Brain Structure, and Cognition: The Role of Cardiovascular Disease Risk Factors

    Directory of Open Access Journals (Sweden)

    Moyra E. Mortby

    2014-01-01

    Full Text Available The protective effect of education on cognitive and brain health is well established. While the direct effects of individual cardiovascular disease (CVD risk factors (i.e., hypertension, smoking, diabetes, and obesity on cerebral structure have been investigated, little is understood about the possible interaction between the protective effect of education and the deleterious effects of CVD risk factors in predicting brain ageing and cognition. Using data from the PATH Through Life study (N=266, we investigated the protective effect of education on cerebral structure and function and tested a possible mediating role of CVD risk factors. Higher education was associated with larger regional grey/white matter volumes in the prefrontal cortex in men only. The association between education and cognition was mediated by brain volumes but only for grey matter and only in relation to information processing speed. CVD risk factors did not mediate the association between regional volumes and cognition. This study provides additional evidence in support for a protective effect of education on cerebral structures and cognition. However, it does not provide support for a mediating role of CVD risk factors in these associations.

  5. Parameters of glucose metabolism and the aging brain: a magnetization transfer imaging study of brain macro- and micro-structure in older adults without diabetes.

    Science.gov (United States)

    Akintola, Abimbola A; van den Berg, Annette; Altmann-Schneider, Irmhild; Jansen, Steffy W; van Buchem, Mark A; Slagboom, P Eline; Westendorp, Rudi G; van Heemst, Diana; van der Grond, Jeroen

    2015-08-01

    Given the concurrent, escalating epidemic of diabetes mellitus and neurodegenerative diseases, two age-related disorders, we aimed to understand the relation between parameters of glucose metabolism and indices of pathology in the aging brain. From the Leiden Longevity Study, 132 participants (mean age 66 years) underwent a 2-h oral glucose tolerance test to assess glucose tolerance (fasted and area under the curve (AUC) glucose), insulin sensitivity (fasted and AUC insulin and homeostatic model assessment of insulin sensitivity (HOMA-IS)) and insulin secretion (insulinogenic index). 3-T brain MRI was used to detect macro-structural damage (atrophy, white matter hyper-intensities, infarcts and/or micro-bleeds) and magnetization transfer imaging (MTI) to detect loss of micro-structural homogeneity that remains otherwise invisible on conventional MRI. Macro-structurally, higher fasted glucose was significantly associated with white matter atrophy (P = 0.028). Micro-structurally, decreased magnetization transfer ratio (MTR) peak height in gray matter was associated with higher fasted insulin (P = 0.010), AUCinsulin (P = 0.001), insulinogenic index (P = 0.008) and lower HOMA-IS index (P macro-structural damage, impaired insulin action was associated more strongly with reduced micro-structural brain parenchymal homogeneity. These findings offer some insight into the association between different parameters of glucose metabolism (impairment of which is characteristic of diabetes mellitus) and brain aging.

  6. Investigation of structural behaviour due to bend-twist couplings in wind turbine blades

    DEFF Research Database (Denmark)

    Fedorov, Vladimir; Dimitrov, Nikolay Krasimiroy; Berggreen, Christian;

    2009-01-01

    The structural behaviour of a composite wind turbine blade with implemented bend-twist coupling is examined in this paper. Several shell finite element models of the blade have been developed and validated against full-scale tests. All shell models performed well for flap-wise bending, but perfor......The structural behaviour of a composite wind turbine blade with implemented bend-twist coupling is examined in this paper. Several shell finite element models of the blade have been developed and validated against full-scale tests. All shell models performed well for flap-wise bending...

  7. Modelling loading and break-up of RC structure due to internal explosion of fragmenting shells

    NARCIS (Netherlands)

    Weerheijm, J.; Stolz, A.; Riedel, W.; Mediavilla, J.

    2012-01-01

    The Klotz Group (KG), an mtemational group of experts on explosion safety, investigates the debris throw hazard associated with the accidental detonation of ammunition in reinforced concrete (RC-) structures. Experiments are combined with engineering models but also with results of advanced computat

  8. Modelling loading and break-up of RC structure due to internal explosion of fragmenting shells

    NARCIS (Netherlands)

    Weerheijm, J.; Stolz, A.; Riedel, W.; Mediavilla Varas, J.

    2012-01-01

    The Klotz Group (KG), an international group of experts on explosion safety, investigates the debris throw hazard associated with the accidental detonation of ammunition in reinforced concrete (RC-) structures. Experiments are combined with engineering models but also with results of advanced comput

  9. Aberrant Global and Regional Topological Organization of the Fractional Anisotropy-weighted Brain Structural Networks in Major Depressive Disorder

    Institute of Scientific and Technical Information of China (English)

    Jian-Huai Chen; Zhi-Jian Yao; Jiao-Long Qin; Rui Yan; Ling-Ling Hua; Qing Lu

    2016-01-01

    Background:Most previous neuroimaging studies have focused on the structural and functional abnormalities of local brain regions in major depressive disorder (MDD).Moreover,the exactly topological organization of networks underlying MDD remains unclear.This study examined the aberrant global and regional topological patterns of the brain white matter networks in MDD patients.Methods:The diffusion tensor imaging data were obtained from 27 patients with MDD and 40 healthy controls.The brain fractional anisotropy-weighted structural networks were constructed,and the global network and regional nodal metrics of the networks were explored by the complex network theory.Results:Compared with the healthy controls,the brain structural network of MDD patients showed an intact small-world topology,but significantly abnormal global network topological organization and regional nodal characteristic of the network in MDD were found.Our findings also indicated that the brain structural networks in MDD patients become a less strongly integrated network with a reduced central role of some key brain regions.Conclusions:All these resulted in a less optimal topological organization of networks underlying MDD patients,including an impaired capability of local information processing,reduced centrality of some brain regions and limited capacity to integrate information across different regions.Thus,these global network and regional node-level aberrations might contribute to understanding the pathogenesis of MDD from the view of the brain network.

  10. From Brain Maps to Cognitive Ontologies: Informatics and the Search for Mental Structure.

    Science.gov (United States)

    Poldrack, Russell A; Yarkoni, Tal

    2016-01-01

    A major goal of cognitive neuroscience is to delineate how brain systems give rise to mental function. Here we review the increasingly large role informatics-driven approaches are playing in such efforts. We begin by reviewing a number of challenges conventional neuroimaging approaches face in trying to delineate brain-cognition mappings--for example, the difficulty in establishing the specificity of postulated associations. Next, we demonstrate how these limitations can potentially be overcome using complementary approaches that emphasize large-scale analysis--including meta-analytic methods that synthesize hundreds or thousands of studies at a time; latent-variable approaches that seek to extract structure from data in a bottom-up manner; and predictive modeling approaches capable of quantitatively inferring mental states from patterns of brain activity. We highlight the underappreciated but critical role for formal cognitive ontologies in helping to clarify, refine, and test theories of brain and cognitive function. Finally, we conclude with a speculative discussion of what future informatics developments may hold for cognitive neuroscience.

  11. The temporal structures and functional significance of scale-free brain activity

    Science.gov (United States)

    He, Biyu J.; Zempel, John M.; Snyder, Abraham Z.; Raichle, Marcus E.

    2010-01-01

    SUMMARY Scale-free dynamics, with a power spectrum following P ∝ f-β, are an intrinsic feature of many complex processes in nature. In neural systems, scale-free activity is often neglected in electrophysiological research. Here, we investigate scale-free dynamics in human brain and show that it contains extensive nested frequencies, with the phase of lower frequencies modulating the amplitude of higher frequencies in an upward progression across the frequency spectrum. The functional significance of scale-free brain activity is indicated by task performance modulation and regional variation, with β being larger in default network and visual cortex and smaller in hippocampus and cerebellum. The precise patterns of nested frequencies in the brain differ from other scale-free dynamics in nature, such as earth seismic waves and stock market fluctuations, suggesting system-specific generative mechanisms. Our findings reveal robust temporal structures and behavioral significance of scale-free brain activity and should motivate future study on its physiological mechanisms and cognitive implications. PMID:20471349

  12. Testing predictions from personality neuroscience. Brain structure and the big five.

    Science.gov (United States)

    DeYoung, Colin G; Hirsh, Jacob B; Shane, Matthew S; Papademetris, Xenophon; Rajeevan, Nallakkandi; Gray, Jeremy R

    2010-06-01

    We used a new theory of the biological basis of the Big Five personality traits to generate hypotheses about the association of each trait with the volume of different brain regions. Controlling for age, sex, and whole-brain volume, results from structural magnetic resonance imaging of 116 healthy adults supported our hypotheses for four of the five traits: Extraversion, Neuroticism, Agreeableness, and Conscientiousness. Extraversion covaried with volume of medial orbitofrontal cortex, a brain region involved in processing reward information. Neuroticism covaried with volume of brain regions associated with threat, punishment, and negative affect. Agreeableness covaried with volume in regions that process information about the intentions and mental states of other individuals. Conscientiousness covaried with volume in lateral prefrontal cortex, a region involved in planning and the voluntary control of behavior. These findings support our biologically based, explanatory model of the Big Five and demonstrate the potential of personality neuroscience (i.e., the systematic study of individual differences in personality using neuroscience methods) as a discipline.

  13. The association of brain structure with gait velocity in older adults: a quantitative volumetric analysis of brain MRI

    International Nuclear Information System (INIS)

    While cortical processes play an important role in controlling locomotion, the underlying structural brain changes associated with slowing of gait in aging are not yet fully established. Our study aimed to examine the relationship between cortical gray matter volume (GM), white matter volume (WM), ventricular volume (VV), hippocampal and hippocampal subfield volumes, and gait velocity in older adults free of dementia. Gait and cognitive performance was tested in 112 community-residing adults, age 70 years and over, participating in the Einstein Aging Study. Gait velocity (cm/s) was obtained using an instrumented walkway. Volumetric MRI measures were estimated using a FreeSurfer software. We examined the cross-sectional relationship of GM, WM, VV, and hippocampal total and subfield volumes and gait velocity using linear regression models. In complementary models, the effect of memory performance on the relationship between gait velocity and regional volumes was evaluated. Slower gait velocity was associated with smaller cortical GM and total hippocampal volumes. There was no association between gait velocity and WM or VV. Among hippocampal subfields, only smaller presubiculum volume was significantly associated with decrease in gait velocity. Addition of the memory performance to the models attenuated the association between gait velocity and all volumetric measures. Our findings indicate that total GM and hippocampal volumes as well as specific hippocampal subfield volumes are inversely associated with locomotor function. These associations are probably affected by cognitive status of study population. (orig.)

  14. The association of brain structure with gait velocity in older adults: a quantitative volumetric analysis of brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ezzati, Ali [Albert Einstein College of Medicine of Yeshiva University, Saul B. Korey Department of Neurology, Bronx, NY (United States); Montefiore Medical Center, Department of Neurology, Bronx, NY (United States); Katz, Mindy J. [Albert Einstein College of Medicine of Yeshiva University, Saul B. Korey Department of Neurology, Bronx, NY (United States); Lipton, Michael L. [Albert Einstein College of Medicine of Yeshiva University, The Gruss Magnetic Resonance Research Center and Departments of Radiology, Psychiatry and Behavioral Sciences and the Dominick P. Purpura Department of Neuroscience, Bronx, NY (United States); Montefiore Medical Center, The Department of Radiology, Bronx, NY (United States); Lipton, Richard B. [Albert Einstein College of Medicine of Yeshiva University, Saul B. Korey Department of Neurology, Bronx, NY (United States); Albert Einstein College of Medicine of Yeshiva University, Department of Epidemiology and Population Health, Bronx, NY (United States); Verghese, Joe [Albert Einstein College of Medicine of Yeshiva University, Saul B. Korey Department of Neurology, Bronx, NY (United States); Albert Einstein College of Medicine, Division of Cognitive and Motor Aging, Bronx, NY (United States)

    2015-08-15

    While cortical processes play an important role in controlling locomotion, the underlying structural brain changes associated with slowing of gait in aging are not yet fully established. Our study aimed to examine the relationship between cortical gray matter volume (GM), white matter volume (WM), ventricular volume (VV), hippocampal and hippocampal subfield volumes, and gait velocity in older adults free of dementia. Gait and cognitive performance was tested in 112 community-residing adults, age 70 years and over, participating in the Einstein Aging Study. Gait velocity (cm/s) was obtained using an instrumented walkway. Volumetric MRI measures were estimated using a FreeSurfer software. We examined the cross-sectional relationship of GM, WM, VV, and hippocampal total and subfield volumes and gait velocity using linear regression models. In complementary models, the effect of memory performance on the relationship between gait velocity and regional volumes was evaluated. Slower gait velocity was associated with smaller cortical GM and total hippocampal volumes. There was no association between gait velocity and WM or VV. Among hippocampal subfields, only smaller presubiculum volume was significantly associated with decrease in gait velocity. Addition of the memory performance to the models attenuated the association between gait velocity and all volumetric measures. Our findings indicate that total GM and hippocampal volumes as well as specific hippocampal subfield volumes are inversely associated with locomotor function. These associations are probably affected by cognitive status of study population. (orig.)

  15. Nanocrystals in compression: unexpected structural phase transition and amorphization due to surface impurities

    Science.gov (United States)

    Liu, Gang; Kong, Lingping; Yan, Jinyuan; Liu, Zhenxian; Zhang, Hengzhong; Lei, Pei; Xu, Tao; Mao, Ho-Kwang; Chen, Bin

    2016-06-01

    We report an unprecedented surface doping-driven anomaly in the compression behaviors of nanocrystals demonstrating that the change of surface chemistry can lead to an interior bulk structure change in nanoparticles. In the synchrotron-based X-ray diffraction experiments, titania nanocrystals with low concentration yttrium dopants at the surface are found to be less compressible than undoped titania nanocrystals. More surprisingly, an unexpected TiO2(ii) phase (α-PbO2 type) is induced and obvious anisotropy is observed in the compression of yttrium-doped TiO2, in sharp contrast to the compression behavior of undoped TiO2. In addition, the undoped brookite nanocrystals remain with the same structure up to 30 GPa, whereas the yttrium-doped brookite amorphizes above 20 GPa. The abnormal structural evolution observed in yttrium-doped TiO2 does not agree with the reported phase stability of nano titania polymorphs, thus suggesting that the physical properties of the interior of nanocrystals can be controlled by the surface, providing an unconventional and new degree of freedom in search for nanocrystals with novel tunable properties that can trigger applications in multiple areas of industry and provoke more related basic science research.We report an unprecedented surface doping-driven anomaly in the compression behaviors of nanocrystals demonstrating that the change of surface chemistry can lead to an interior bulk structure change in nanoparticles. In the synchrotron-based X-ray diffraction experiments, titania nanocrystals with low concentration yttrium dopants at the surface are found to be less compressible than undoped titania nanocrystals. More surprisingly, an unexpected TiO2(ii) phase (α-PbO2 type) is induced and obvious anisotropy is observed in the compression of yttrium-doped TiO2, in sharp contrast to the compression behavior of undoped TiO2. In addition, the undoped brookite nanocrystals remain with the same structure up to 30 GPa, whereas the yttrium

  16. DURABILITY OF CONCRETE STRUCTURES STRENGTHENED EXTERNALLY USING FIBER REINFORCED POLYMER (FRP) AND IT???S PERFORMANCE DUE TO SEA ENVIRONTMENT

    OpenAIRE

    RUDY DJAMALUDDIN; . IRMAWATI; . SHINICHI HINO

    2014-01-01

    Overall objective of the research is to establish a strengthening method for damaged concrete structures using Fiber Reinforced Plastics (FRP) as well as to have an understanding of the effect of the tropic and sub-tropic sea environment to its durability and performance. Due to the change of the life demands, the structures may be experiencing changes in the function and an increase in service load so that the structures is no longer safe for use and it may cause a damage on th...

  17. 3D active shape models of human brain structures: application to patient-specific mesh generation

    Science.gov (United States)

    Ravikumar, Nishant; Castro-Mateos, Isaac; Pozo, Jose M.; Frangi, Alejandro F.; Taylor, Zeike A.

    2015-03-01

    The use of biomechanics-based numerical simulations has attracted growing interest in recent years for computer-aided diagnosis and treatment planning. With this in mind, a method for automatic mesh generation of brain structures of interest, using statistical models of shape (SSM) and appearance (SAM), for personalised computational modelling is presented. SSMs are constructed as point distribution models (PDMs) while SAMs are trained using intensity profiles sampled from a training set of T1-weighted magnetic resonance images. The brain structures of interest are, the cortical surface (cerebrum, cerebellum & brainstem), lateral ventricles and falx-cerebri membrane. Two methods for establishing correspondences across the training set of shapes are investigated and compared (based on SSM quality): the Coherent Point Drift (CPD) point-set registration method and B-spline mesh-to-mesh registration method. The MNI-305 (Montreal Neurological Institute) average brain atlas is used to generate the template mesh, which is deformed and registered to each training case, to establish correspondence over the training set of shapes. 18 healthy patients' T1-weightedMRimages form the training set used to generate the SSM and SAM. Both model-training and model-fitting are performed over multiple brain structures simultaneously. Compactness and generalisation errors of the BSpline-SSM and CPD-SSM are evaluated and used to quantitatively compare the SSMs. Leave-one-out cross validation is used to evaluate SSM quality in terms of these measures. The mesh-based SSM is found to generalise better and is more compact, relative to the CPD-based SSM. Quality of the best-fit model instance from the trained SSMs, to test cases are evaluated using the Hausdorff distance (HD) and mean absolute surface distance (MASD) metrics.

  18. Abnormal structural connectivity in the brain networks of children with hydrocephalus.

    Science.gov (United States)

    Yuan, Weihong; Holland, Scott K; Shimony, Joshua S; Altaye, Mekibib; Mangano, Francesco T; Limbrick, David D; Jones, Blaise V; Nash, Tiffany; Rajagopal, Akila; Simpson, Sarah; Ragan, Dustin; McKinstry, Robert C

    2015-01-01

    Increased intracranial pressure and ventriculomegaly in children with hydrocephalus are known to have adverse effects on white matter structure. This study seeks to investigate the impact of hydrocephalus on topological features of brain networks in children. The goal was to investigate structural network connectivity, at both global and regional levels, in the brains in children with hydrocephalus using graph theory analysis and diffusion tensor tractography. Three groups of children were included in the study (29 normally developing controls, 9 preoperative hydrocephalus patients, and 17 postoperative hydrocephalus patients). Graph theory analysis was applied to calculate the global network measures including small-worldness, normalized clustering coefficients, normalized characteristic path length, global efficiency, and modularity. Abnormalities in regional network parameters, including nodal degree, local efficiency, clustering coefficient, and betweenness centrality, were also compared between the two patients groups (separately) and the controls using two tailed t-test at significance level of p hydrocephalus in both the preoperative and postoperative groups were found to have significantly lower small-worldness and lower normalized clustering coefficient than controls. Children with hydrocephalus in the postoperative group were also found to have significantly lower normalized characteristic path length and lower modularity. At regional level, significant group differences (or differences at trend level) in regional network measures were found between hydrocephalus patients and the controls in a series of brain regions including the medial occipital gyrus, medial frontal gyrus, thalamus, cingulate gyrus, lingual gyrus, rectal gyrus, caudate, cuneus, and insular. Our data showed that structural connectivity analysis using graph theory and diffusion tensor tractography is sensitive to detect abnormalities of brain network connectivity associated with

  19. Abnormal structural connectivity in the brain networks of children with hydrocephalus

    Directory of Open Access Journals (Sweden)

    Weihong Yuan

    2015-01-01

    Full Text Available Increased intracranial pressure and ventriculomegaly in children with hydrocephalus are known to have adverse effects on white matter structure. This study seeks to investigate the impact of hydrocephalus on topological features of brain networks in children. The goal was to investigate structural network connectivity, at both global and regional levels, in the brains in children with hydrocephalus using graph theory analysis and diffusion tensor tractography. Three groups of children were included in the study (29 normally developing controls, 9 preoperative hydrocephalus patients, and 17 postoperative hydrocephalus patients. Graph theory analysis was applied to calculate the global network measures including small-worldness, normalized clustering coefficients, normalized characteristic path length, global efficiency, and modularity. Abnormalities in regional network parameters, including nodal degree, local efficiency, clustering coefficient, and betweenness centrality, were also compared between the two patients groups (separately and the controls using two tailed t-test at significance level of p < 0.05 (corrected for multiple comparison. Children with hydrocephalus in both the preoperative and postoperative groups were found to have significantly lower small-worldness and lower normalized clustering coefficient than controls. Children with hydrocephalus in the postoperative group were also found to have significantly lower normalized characteristic path length and lower modularity. At regional level, significant group differences (or differences at trend level in regional network measures were found between hydrocephalus patients and the controls in a series of brain regions including the medial occipital gyrus, medial frontal gyrus, thalamus, cingulate gyrus, lingual gyrus, rectal gyrus, caudate, cuneus, and insular. Our data showed that structural connectivity analysis using graph theory and diffusion tensor tractography is sensitive to

  20. Acceleration response spectrum for prediction of structural vibration due to individual bouncing

    Science.gov (United States)

    Chen, Jun; Wang, Lei; Racic, Vitomir; Lou, Jiayue

    2016-08-01

    This study is designed to develop an acceleration response spectrum that can be used in vibration serviceability assessment of civil engineering structures, such as floors and grandstands those are dynamically excited by individual bouncing. The spectrum is derived from numerical simulations and statistical analysis of acceleration responses of a single degree of freedom system with variable natural frequency and damping under a large number of experimentally measured individual bouncing loads. Its mathematical representation is fit for fast yet reliable application in design practice and is comprised of three equations that describe three distinct frequency regions observed in the actual data: the first resonant plateau (2-3.5 Hz), the second resonant plateau (4-7 Hz) and a descension region (7-15 Hz). Finally, this paper verifies the proposed response spectrum approach to predict structural vibration by direct comparison against numerical simulations and experimental results.

  1. Magnetic Doppler imaging considering atmospheric structure modifications due to local abundances: a luxury or a necessity?

    CERN Document Server

    Kochukhov, O; Shulyak, D

    2012-01-01

    Magnetic Doppler imaging is currently the most powerful method of interpreting high-resolution spectropolarimetric observations of stars. This technique has revealed the presence of unexpected small-scale magnetic fields on the surfaces of Ap stars. These studies were recently criticisied by Stift et al. (2012), who claimed that magnetic inversions are not robust and are undermined by neglecting a feedback on the Stokes line profiles from the local atmospheric structure in the regions of enhanced metal abundance. We show that Stift et al. misinterpreted published magnetic Doppler imaging results and neglected some of the most fundamental principles behind magnetic mapping. We demonstrate that the variation of atmospheric structure across the surface of a star with chemical spots affects the local continuum intensity but is negligible for the normalised local Stokes profiles. For the disk-integrated spectra of an Ap star with extreme abundance variations, we find that the assumption of a mean model atmosphere ...

  2. Stream invertebrate communities of Mongolia: current structure and expected changes due to climate change

    OpenAIRE

    Maasri, Alain; Gelhaus, Jon

    2012-01-01

    Background Mongolia’s riverine landscape is divided into three watersheds, differing in extent of permafrost, amount of precipitation and in hydrological connectivity between sub-drainages. In order to assess the vulnerability of macroinvertebrate communities to ongoing climate change, we consider the taxonomic and functional structures of stream communities in two major watersheds: The Central Asian Internal Watershed (CAIW) and the Arctic Ocean Watershed (AOW), together covering 86.1% of Mo...

  3. New interpretation of arterial stiffening due to cigarette smoking using a structurally motivated constitutive model

    DEFF Research Database (Denmark)

    Enevoldsen, Majken; Henneberg, K-A; Jensen, J A;

    2011-01-01

    Cigarette smoking is the leading self-inflicted risk factor for cardiovascular diseases; it causes arterial stiffening with serious sequelea including atherosclerosis and abdominal aortic aneurysms. This work presents a new interpretation of arterial stiffening caused by smoking based on data...... published for rat pulmonary arteries. A structurally motivated "four fiber family" constitutive relation was used to fit the available biaxial data and associated best-fit values of material parameters were estimated using multivariate nonlinear regression. Results suggested that arterial stiffening caused...

  4. Diffusion in Cytoplasm: Effects of Excluded Volume Due to Internal Membranes and Cytoskeletal Structures

    OpenAIRE

    Novak, Igor L.; Kraikivski, Pavel; Slepchenko, Boris M.

    2009-01-01

    The intricate geometry of cytoskeletal networks and internal membranes causes the space available for diffusion in cytoplasm to be convoluted, thereby affecting macromolecule diffusivity. We present a first systematic computational study of this effect by approximating intracellular structures as mixtures of random overlapping obstacles of various shapes. Effective diffusion coefficients are computed using a fast homogenization technique. It is found that a simple two-parameter power law prov...

  5. Cosmological implications in electrodynamics due to variations of the fine structure constant

    CERN Document Server

    Martínez-Ledesma, J L

    2002-01-01

    Astronomical observations are strongly suggesting that the fine structure constant varies cosmologically. We present an analysis on the consequences that this variations might induce on the electromagnetic field as a whole. We show that under this circumstances the electrodynamics in vacuum of the universe are described by two fields, the ``standard'' Maxwell's field and a new scalar field. We provide a generalized Lorentz force which can be used to test our results experimentally.

  6. Modelling loading and break-up of RC structure due to internal explosion of fragmenting shells

    OpenAIRE

    Weerheijm, J.; Stolz, A; Riedel , W.; Mediavilla, J.

    2012-01-01

    The Klotz Group (KG), an mtemational group of experts on explosion safety, investigates the debris throw hazard associated with the accidental detonation of ammunition in reinforced concrete (RC-) structures. Experiments are combined with engineering models but also with results of advanced computational modeling, which is the topie of this paper. EMI and TNO are establishing a three step approach to analyze the explosion phenomena of single and multiple bare and cased charges in a RC structu...

  7. Evolution of nano-structures of silver due to rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, Shyamal, E-mail: shyamal.mondal@saha.ac.in; Bhattacharyya, S. R., E-mail: shyamal.mondal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)

    2014-04-24

    This report deals with rapid thermal annealing (RTA) effect on continuous silver film on Si(100) substrate. For this purpose silver films of different thicknesses were deposited and subsequently annealed at 500 and 800 °C. The as-deposited and annealed samples were investigated by scanning electron microscope (SEM). Formations of different nano-structures have been observed. Fragmentation of formed nanoislands also observed at temperature below melting temperature.

  8. Oscillatory structural forces due to nonionic surfactant micelles: data by colloidal-probe AFM vs theory.

    Science.gov (United States)

    Christov, Nikolay C; Danov, Krassimir D; Zeng, Yan; Kralchevsky, Peter A; von Klitzing, Regine

    2010-01-19

    Micellar solutions of nonionic surfactants Brij 35 and Tween 20 are confined between two surfaces in a colloidal-probe atomic-force microscope (CP-AFM). The experimentally detected oscillatory forces due to the layer-by-layer expulsion of the micelles agree very well with the theoretical predictions for hard-sphere fluids. While the experiment gives parts of the stable branches of the force curve, the theoretical model allows reconstruction of the full oscillatory curve. Therewith, the strength and range of the ordering could be determined. The resulting aggregation number from the fits of the force curves for Brij 35 is close to 70 and exhibits a slight tendency to increase with the surfactant concentration. The last layer of micelles cannot be pressed out. The measured force-vs-distance curve has nonequilibrium portions, which represent "jumps" from one to another branch of the respective equilibrium oscillatory curve. In the case of Brij 35, at concentrations force oscillations are almost suppressed, which implies that the micelles of this surfactant are labile and are demolished by the hydrodynamic shear stresses due to the colloidal-probe motion. The comparison of the results for the two surfactants demonstrates that in some cases the micelles can be destroyed by the CP-AFM, but in other cases they can be stable and behave as rigid particles. This behavior correlates with the characteristic times of the slow micellar relaxation process for these surfactants. PMID:20067306

  9. Dynamic investigations of various civil engineering structures due to ambient and mining tremors

    Directory of Open Access Journals (Sweden)

    Kuzniar Krystyna

    2015-01-01

    Full Text Available The first part of the study deals with evaluation of dynamic characteristics of selected typical industrial facilities, such as the extraction steel tower, reinforced concrete tower skips. These structures are located in the coal mine area. The constructions of the test items are varied and complicated, which causes difficulties in the research in situ. In the investigation we used normal and emergency operation of lifting equipment, the effect of wind gusts and rhythmic man swaying. The second part of the study involves the determination of the dynamic characteristics of tailing dam. In this case mining tremors were used as the sources of vibration excitations. By using natural vibration excitation source it was possible to determine the lowest frequency of free vibration of the tailing dam. The third part of the paper focuses on the results of measurements of mine-induced ground vibrations and vibrations of residential buildings of various types. Typical one-family masonry houses as well as 5 and 12 storey reinforced prefabricated buildings were examined. The studies were conducted to determine the transmission of free-field vibrations to the building foundations. According to the significant differences between the simultaneously measured ground and building foundation vibrations, results of experimental tests obtained by means of response spectra are essential for the proper adoption of kinematic loads for dynamic models of these structures. The results of experimental studies were the basis for the verification of dynamic models of investigated structures.

  10. Dynamic Wave Pressures on Deeply Embedded Large Cylindrical Structures due to Random Waves

    Institute of Scientific and Technical Information of China (English)

    刘海笑; 唐云; 周锡礽

    2003-01-01

    The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves, and accordingly to offer valuable findings for engineering, the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different embedment depths in response to two wave spectra.The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain. By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder, experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory, and detailed comparisons were also carried out between the single and continuous cylinders. Some new findings and the corresponding analysis are reported in present paper. The investigation on continuous cylinders will be used in particular for reference in engineering applications because information is scarce on studying such kind of problem both analytically and experimentally.

  11. Structural linear measurements in the newborn brain: accuracy of cranial ultrasound compared to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Leijser, Lara M. [Hammersmith Hospital, Imperial College, Department of Paediatrics, London (United Kingdom); Srinivasan, Latha; Cowan, Frances M. [Hammersmith Hospital, Imperial College, Department of Paediatrics, London (United Kingdom); Hammersmith Hospital, Imperial College, Department of Imaging Sciences, London (United Kingdom); Rutherford, Mary A.; Counsell, Serena J.; Allsop, Joanna M. [Hammersmith Hospital, Imperial College, Department of Imaging Sciences, London (United Kingdom)

    2007-07-15

    Structural size in the neonatal brain is of clinical importance. Cranial ultrasonography (cUS) is the primary method used for evaluating the neonatal brain and it is important to know whether linear measurements made using this technique are accurate. To compare linear measurements of different cerebral structures made from neonatal cUS and contemporaneous MRI. Preterm and term infants studies with cUS and MRI on the same day were studied. Linear measurements made using both techniques from many cerebral structures were compared using a paired t-test. A total of 44 sets of scans from 26 preterm and 8 term infants were assessed. Small but significant differences between the cUS and MRI measurements (P<0.05) were found for the ventricular index, the posterior horn depth of the lateral ventricle, the extracerebral space and interhemispheric fissure, and the cortex of the cingulate gyrus. No significant differences were found for any other measurements. Linear measurements from cUS are accurate for most neonatal cerebral structures. Significant differences compared to MRI were found for a few structures, but only for the cortex were the absolute differences marked and possibly of clinical importance. (orig.)

  12. Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27.

    Science.gov (United States)

    Peddibhotla, Sirisha; Nagamani, Sandesh C S; Erez, Ayelet; Hunter, Jill V; Holder, J Lloyd; Carlin, Mary E; Bader, Patricia I; Perras, Helene M F; Allanson, Judith E; Newman, Leslie; Simpson, Gayle; Immken, LaDonna; Powell, Erin; Mohanty, Aaron; Kang, Sung-Hae L; Stankiewicz, Pawel; Bacino, Carlos A; Bi, Weimin; Patel, Ankita; Cheung, Sau W

    2015-01-01

    Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype-phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7 Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies.

  13. Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27.

    Science.gov (United States)

    Peddibhotla, Sirisha; Nagamani, Sandesh C S; Erez, Ayelet; Hunter, Jill V; Holder, J Lloyd; Carlin, Mary E; Bader, Patricia I; Perras, Helene M F; Allanson, Judith E; Newman, Leslie; Simpson, Gayle; Immken, LaDonna; Powell, Erin; Mohanty, Aaron; Kang, Sung-Hae L; Stankiewicz, Pawel; Bacino, Carlos A; Bi, Weimin; Patel, Ankita; Cheung, Sau W

    2015-01-01

    Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype-phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7 Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies. PMID:24736736

  14. From the genome to the phenome and back: linking genes with human brain function and structure using genetically informed neuroimaging

    DEFF Research Database (Denmark)

    Siebner, H R; Callicott, J H; Sommer, T;

    2009-01-01

    In recent years, an array of brain mapping techniques has been successfully employed to link individual differences in circuit function or structure in the living human brain with individual variations in the human genome. Several proof-of-principle studies provided converging evidence that brain...... imaging can establish important links between genes and behaviour. The overarching goal is to use genetically informed brain imaging to pinpoint neurobiological mechanisms that contribute to behavioural intermediate phenotypes or disease states. This special issue on "Linking Genes to Brain Function......, the integration of genetic and neuroimaging data also poses major methodological and conceptual challenges. Therefore, this special issue also focuses on how these challenges can be met to fully exploit the synergism of genetically informed brain imaging....

  15. Brain Basics

    Medline Plus

    Full Text Available ... How the brain develops How genes and the environment affect the brain The basic structure of the ... inside contents of the cell from its surrounding environment and controls what enters and leaves the cell, ...

  16. Brain Basics

    Medline Plus

    Full Text Available ... may help improve treatments for anxiety disorders like phobias or post-traumatic stress disorder (PTSD) . Prefrontal cortex ( ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as ...

  17. Brain Basics

    Medline Plus

    Full Text Available ... neurons, the most highly specialized cells of all, conduct messages. Every cell in our bodies contains a ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as ...

  18. Brain structural correlates of schizotypy and psychosis proneness in a non-clinical healthy volunteer sample.

    Science.gov (United States)

    Nenadic, Igor; Lorenz, Carsten; Langbein, Kerstin; Dietzek, Maren; Smesny, Stefan; Schönfeld, Nils; Fañanás, Lourdes; Sauer, Heinrich; Gaser, Christian

    2015-10-01

    Schizotypal traits are phenotypic risk factors for schizophrenia, associated with biological changes across a putative schizophrenia spectrum. In this study, we tested the hypothesis that brain structural changes in key brain areas relevant to this spectrum (esp. medial and lateral prefrontal cortex) would vary across different degrees of schizotypal trait expression and/or phenotypic markers of psychosis proneness in healthy non-clinical volunteers. We analysed high-resolution 3Tesla magnetic resonance images (MRI) of 59 healthy volunteers using voxel-based morphometry (VBM), correlating grey matter values to the positive and negative symptom factors of the schizotypal personality questionnaire (SPQ, German version) and a measure of psychosis proneness (community assessment of psychic experiences, CAPE). We found positive correlations between positive SPQ dimension and bilateral inferior and right superior frontal cortices, and positive CAPE dimension and left inferior frontal cortex, as well as CAPE negative dimension and right supplementary motor area (SMA) and left inferior parietal cortex. However, only the positive correlation of the right precuneus with negative schizotypy scores was significant after FWE correction for multiple comparisons. Our findings confirm an effect of schizotypal traits and psychosis proneness on brain structure in healthy subjects, providing further support to a biological continuum model. PMID:26164819

  19. Effects of yoga on brain waves and structural activation: A review.

    Science.gov (United States)

    Desai, Radhika; Tailor, Anisha; Bhatt, Tanvi

    2015-05-01

    Previous research has shown the vast mental and physical health benefits associated with yoga. Yoga practice can be divided into subcategories that include posture-holding exercise (asana), breathing (pranayama, Kriya), and meditation (Sahaj) practice. Studies measuring mental health outcomes have shown decreases in anxiety, and increases in cognitive performance after yoga interventions. Similar studies have also shown cognitive advantages amongst yoga practitioners versus non-practitioners. The mental health and cognitive benefits of yoga are evident, but the physiological and structural changes in the brain that lead to this remain a topic that lacks consensus. Therefore, the purpose of this study was to examine and review existing literature on the effects of yoga on brain waves and structural changes and activation. After a narrowed search through a set of specific inclusion and exclusion criteria, 15 articles were used in this review. It was concluded that breathing, meditation, and posture-based yoga increased overall brain wave activity. Increases in graygray matter along with increases in amygdala and frontal cortex activation were evident after a yoga intervention. Yoga practice may be an effective adjunctive treatment for a clinical and healthy aging population. Further research can examine the effects of specific branches of yoga on a designated clinical population.

  20. Brain structural correlates of risk-taking behavior and effects of peer influence in adolescents.

    Directory of Open Access Journals (Sweden)

    Myoung Soo Kwon

    Full Text Available Adolescents are characterized by impulsive risky behavior, particularly in the presence of peers. We discriminated high and low risk-taking male adolescents aged 18-19 years by assessing their propensity for risky behavior and vulnerability to peer influence with personality tests, and compared structural differences in gray and white matter of the brain with voxel-based morphometry (VBM and diffusion tensor imaging (DTI, respectively. We also compared the brain structures according to the participants' actual risk-taking behavior in a simulated driving task with two different social conditions making up a peer competition situation. There was a discrepancy between the self-reported personality test results and risky driving behavior (running through an intersection with traffic lights turning yellow, chancing a collision with another vehicle. Comparison between high and low risk-taking adolescents according to personality test results revealed no significant difference in gray matter volume and white matter integrity. However, comparison according to actual risk-taking behavior during task performance revealed significantly higher white matter integrity in the high risk-taking group, suggesting that increased risky behavior during adolescence is not necessarily attributed to the immature brain as conventional wisdom says.

  1. Effects of yoga on brain waves and structural activation: A review.

    Science.gov (United States)

    Desai, Radhika; Tailor, Anisha; Bhatt, Tanvi

    2015-05-01

    Previous research has shown the vast mental and physical health benefits associated with yoga. Yoga practice can be divided into subcategories that include posture-holding exercise (asana), breathing (pranayama, Kriya), and meditation (Sahaj) practice. Studies measuring mental health outcomes have shown decreases in anxiety, and increases in cognitive performance after yoga interventions. Similar studies have also shown cognitive advantages amongst yoga practitioners versus non-practitioners. The mental health and cognitive benefits of yoga are evident, but the physiological and structural changes in the brain that lead to this remain a topic that lacks consensus. Therefore, the purpose of this study was to examine and review existing literature on the effects of yoga on brain waves and structural changes and activation. After a narrowed search through a set of specific inclusion and exclusion criteria, 15 articles were used in this review. It was concluded that breathing, meditation, and posture-based yoga increased overall brain wave activity. Increases in graygray matter along with increases in amygdala and frontal cortex activation were evident after a yoga intervention. Yoga practice may be an effective adjunctive treatment for a clinical and healthy aging population. Further research can examine the effects of specific branches of yoga on a designated clinical population. PMID:25824030

  2. Age of language learning shapes brain structure: a cortical thickness study of bilingual and monolingual individuals.

    Science.gov (United States)

    Klein, Denise; Mok, Kelvin; Chen, Jen-Kai; Watkins, Kate E

    2014-04-01

    We examined the effects of learning a second language (L2) on brain structure. Cortical thickness was measured in the MRI datasets of 22 monolinguals and 66 bilinguals. Some bilingual subjects had learned both languages simultaneously (0-3 years) while some had learned their L2 after achieving proficiency in their first language during either early (4-7 years) or late childhood (8-13 years). Later acquisition of L2 was associated with significantly thicker cortex in the left inferior frontal gyrus (IFG) and thinner cortex in the right IFG. These effects were seen in the group comparisons of monolinguals, simultaneous bilinguals and early and late bilinguals. Within the bilingual group, significant correlations between age of acquisition of L2 and cortical thickness were seen in the same regions: cortical thickness correlated with age of acquisition positively in the left IFG and negatively in the right IFG. Interestingly, the monolinguals and simultaneous bilinguals did not differ in cortical thickness in any region. Our results show that learning a second language after gaining proficiency in the first language modifies brain structure in an age-dependent manner whereas simultaneous acquisition of two languages has no additional effect on brain development. PMID:23819901

  3. Age of language learning shapes brain structure: a cortical thickness study of bilingual and monolingual individuals.

    Science.gov (United States)

    Klein, Denise; Mok, Kelvin; Chen, Jen-Kai; Watkins, Kate E

    2014-04-01

    We examined the effects of learning a second language (L2) on brain structure. Cortical thickness was measured in the MRI datasets of 22 monolinguals and 66 bilinguals. Some bilingual subjects had learned both languages simultaneously (0-3 years) while some had learned their L2 after achieving proficiency in their first language during either early (4-7 years) or late childhood (8-13 years). Later acquisition of L2 was associated with significantly thicker cortex in the left inferior frontal gyrus (IFG) and thinner cortex in the right IFG. These effects were seen in the group comparisons of monolinguals, simultaneous bilinguals and early and late bilinguals. Within the bilingual group, significant correlations between age of acquisition of L2 and cortical thickness were seen in the same regions: cortical thickness correlated with age of acquisition positively in the left IFG and negatively in the right IFG. Interestingly, the monolinguals and simultaneous bilinguals did not differ in cortical thickness in any region. Our results show that learning a second language after gaining proficiency in the first language modifies brain structure in an age-dependent manner whereas simultaneous acquisition of two languages has no additional effect on brain development.

  4. New interpretation of arterial stiffening due to cigarette smoking using a structurally motivated constitutive model

    DEFF Research Database (Denmark)

    Enevoldsen, Marie Sand; Henneberg, Kaj-Åge; Jensen, Jørgen Arendt;

    2011-01-01

    Cigarette smoking is the leading self-inflicted risk factor for cardiovascular diseases; it causes arterial stiffening with serious sequelea including atherosclerosis and abdominal aortic aneurysms. This work presents a new interpretation of arterial stiffening caused by smoking based on data...... published for rat pulmonary arteries. A structurally motivated ‘‘four fiber family’’ constitutive relation was used to fit the available biaxial data and associated best-fit values of material parameters were estimated using multivariate nonlinear regression. Results suggested that arterial stiffening...

  5. Differences in structure and magnetic behavior of Mn-AlN films due to substrate material

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Takanobu; Nakatani, Ryoichi [Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University (Japan); Endo, Yasushi [Depertment of Electrical and Communication Engineering, Graduate School of Engineering, Tohoku University (Japan); Kirino, Fumiyoshi [Conservation of Cultural Property, Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music (Japan)], E-mail: takanobu.sato@mat.eng.osaka-u.ac.jp

    2009-05-01

    The structure and magnetic behavior of Mn-AlN (Al{sub 1-x}Mn{sub x}N, x = 0.03, 0.04) films deposited on thermally oxidized Si (001) substrates and sapphire (0001) substrates were studied. Mn-AlN films deposited on each substrate had a wuertzite-type AlN phase with a preferentially oriented c-axis. Mn-AlN films that were deposited on Si (001) substrate exhibited paramagnetic behavior. In addition to paramagnetic behavior, weak ferromagnetic behavior with curie temperatures higher than room temperature were observed for Mn-AlN films deposited on sapphire (0001) substrates.

  6. Beam Momentum Changes due to Discharges in High-gradient Accelerator Structures

    OpenAIRE

    Palaia, Andrea

    2013-01-01

    The key questions left unanswered by the Standard Model, and the recent discovery of a Standard Model-like Higgs boson, demand an extension of the research on particle physics to the TeV energy scale. The Compact Linear Collider, CLIC, is a candidate project to achieve such goal. It is a linear lepton collider based on a novel two-beam acceleration scheme capable of high-gradient acceleration in X-band accelerator structures. The high electric fields required, however, entail the occurrence o...

  7. Electromagnetic wave band structure due to surface plasmon resonances in a complex plasma.

    Science.gov (United States)

    Vladimirov, S V; Ishihara, O

    2016-07-01

    The dielectric properties of complex plasma containing either metal or dielectric spherical inclusions (macroparticles, dust) are investigated. We focus on surface plasmon resonances on the macroparticle surfaces and their effect on electromagnetic wave propagation. It is demonstrated that the presence of surface plasmon oscillations can significantly modify plasma electromagnetic properties by resonances and cutoffs in the effective permittivity. This leads to related branches of electromagnetic waves and to the wave band gaps. The conditions necessary to observe the band-gap structure in laboratory dusty plasma and/or space (cosmic) dusty plasmas are discussed. PMID:27575225

  8. Electromagnetic wave band structure due to surface plasmon resonances in a complex plasma

    Science.gov (United States)

    Vladimirov, S. V.; Ishihara, O.

    2016-07-01

    The dielectric properties of complex plasma containing either metal or dielectric spherical inclusions (macroparticles, dust) are investigated. We focus on surface plasmon resonances on the macroparticle surfaces and their effect on electromagnetic wave propagation. It is demonstrated that the presence of surface plasmon oscillations can significantly modify plasma electromagnetic properties by resonances and cutoffs in the effective permittivity. This leads to related branches of electromagnetic waves and to the wave band gaps. The conditions necessary to observe the band-gap structure in laboratory dusty plasma and/or space (cosmic) dusty plasmas are discussed.

  9. Structural brain alterations in patients with lumbar disc herniation: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Michael Luchtmann

    Full Text Available Chronic pain is one of the most common health complaints in industrial nations. For example, chronic low back pain (cLBP disables millions of people across the world and generates a tremendous economic burden. While previous studies provided evidence of widespread functional as well as structural brain alterations in chronic pain, little is known about cortical changes in patients suffering from lumbar disc herniation. We investigated morphometric alterations of the gray and white matter of the brain in patients suffering from LDH. The volumes of the gray and white matter of 12 LDH patients were determined in a prospective study and compared to the volumes of healthy controls to distinguish local differences. High-resolution MRI brain images of all participants were performed using a 3 Tesla MRI scanner. Voxel-based morphometry was used to investigate local differences in gray and white matter volume between patients suffering from LDH and healthy controls. LDH patients showed significantly reduced gray matter volume in the right anterolateral prefrontal cortex, the right temporal lobe, the left premotor cortex, the right caudate nucleus, and the right cerebellum as compared to healthy controls. Increased gray matter volume, however, was found in the right dorsal anterior cingulate cortex, the left precuneal cortex, the left fusiform gyrus, and the right brainstem. Additionally, small subcortical decreases of the white matter were found adjacent to the left prefrontal cortex, the right premotor cortex and in the anterior limb of the left internal capsule. We conclude that the lumbar disk herniation can lead to specific local alterations of the gray and white matter in the human brain. The investigation of LDH-induced brain alterations could provide further insight into the underlying nature of the chronification processes and could possibly identify prognostic factors that may improve the conservative as well as the operative treatment of the

  10. Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Christina; Arsic, Milan; Boucard, Christine C.; Biberacher, Viola; Nunnemann, Sabine; Muehlau, Mark [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center, Klinikum rechts der Isar, Munich (Germany); Schmidt, Paul [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Ludwig-Maximilians-University Muenchen, Department of Statistics, Munich (Germany); Roettinger, Michael [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Muenchner Institut fuer Neuroradiologie, Munich (Germany); Etgen, Thorleif [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Klinikum Traunstein, Department of Neurology, Traunstein (Germany); Koutsouleris, Nikolaos; Meisenzahl, Eva M. [Ludwig-Maximilians-Universitaet Muenchen, Department of Psychiatry and Psychotherapy, Munich (Germany); Reiser, Maximilian [Ludwig-Maximilians-Universitaet, Department of Radiology, Munich (Germany)

    2013-08-15

    Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited. In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM). First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient. UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts. (orig.)

  11. Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI

    International Nuclear Information System (INIS)

    Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited. In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM). First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient. UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts. (orig.)

  12. Perturbation-induced secondary flow structures due to fractured stents in arterial curvatures

    Science.gov (United States)

    Bulusu, Kartik V.; Popma, Christopher; Penna, Leanne; Plesniak, Michael W.

    2012-11-01

    An in vitro experimental investigation of secondary flow structures was performed downstream of a model stent that embodied a ``Type-IV'' stent fracture, i.e. complete transverse fracture of elements and element displacement (of 3 diameters). One part of the fractured stent was located in the curved region of a test section comprised of a 180-degree bent tube, and the velocity field measured with PIV. Secondary flow morphologies downstream of the stent were identified with a continuous wavelet transform (CWT) algorithm (PIVlet 1.2) using a 2D Ricker wavelet. A comparison of wavelet transformed vorticity fields of fractured and unfractured model stents is presented under physiological inflow conditions. During systolic deceleration, a breakdown in symmetry of vortical structures occurred with the unfractured stent, but not with the fractured model stent. Potential mechanisms to explain the differences in secondary flow morphologies include redirection of vorticity from the meridional plane of the bend to the normal plane and diffusion of vorticity. Supported by the National Science Foundation, Grant No. CBET-0828903 and GW Center for Biomimetics and Bioinspired Engineering (COBRE).

  13. The energy-dependent position of the IBEX ribbon due to the solar wind structure

    CERN Document Server

    Swaczyna, Paweł; Sokół, Justyna M

    2016-01-01

    Observations of energetic neutral atoms (ENAs) allow for remote studies of the plasma condition in the heliosphere and the neighboring local interstellar medium. The first IBEX results revealed an arc-like enhancement of the ENA flux in the sky, known as the ribbon. The ribbon was not expected from the heliospheric models prior to the IBEX launch. One of the proposed explanations of the ribbon is the mechanism of the secondary ENA emission. The ribbon reveals energy-dependent structure in the relative intensity along its circumference and in the position. Namely, the ribbon geometric center varies systematically by about 10$^\\circ$ in the energy range 0.7-4.3 keV. Here, we show by analytic modeling that this effect is a consequence of the helio-latitudinal structure of the solar wind reflected in the secondary ENAs. Along with a recently measured distance to the ribbon source just beyond the heliopause, our findings support the connection of the ribbon with the local interstellar magnetic field by the mechani...

  14. Dynamic Performance on Multi Storey Structure Due to Ground Borne Vibrations Input from Passing Vehicles

    Directory of Open Access Journals (Sweden)

    Tuan Norhayati Tuan Chik

    2013-12-01

    Full Text Available Ground borne vibration from passing vehicles could excite the adjacent ground, hence produces a vibration waves that will propagate through layers of soil towards the foundations of any adjacent building. This vibration could affects the structure of the building at some levels and even the low sensitivity equipment are also could be affected as well. The objectives of this study are to perform the structural response on multi storey building subjected to ground vibrations input and to determine the level of vibration at each floor from road traffic on the observed building. The scopes of the study are focused on the groundborne vibrations induced by the passing vehicles and analyse the data by using dynamic software such as ANSYSv14 and MATLAB. The selected building for this study is the Registrar Office building which is located in Universiti Tun Hussein Onn Malaysia (UTHM. The inputs of the vibration were measured by using Laser Doppler Vibrometer (LDV equipment. By conducting the field measurement, a real input of ground borne vibration from the loads of vehicle towards any adjacent building can be obtained. Finally, the vibration level from road traffic on office building can be determined using overseas generic criteria guidelines. The vibration level achieved for this building is at above the ISO level, which is suitable for office building and within acceptable limit.

  15. Neuronal process structure and growth proteins are targets of heavy PTM regulation during brain development

    DEFF Research Database (Denmark)

    Edwards, Alistair V G; Schwämmle, Veit; Larsen, Martin Røssel

    2014-01-01

    UNLABELLED: Brain development is a process requiring precise control of many different cell types. One method to achieve this is through specific and temporally regulated modification of proteins in order to alter structure and function. Post-translational modification (PTM) of proteins is known...... to have wide-ranging and substantial effects on cellular function, both as part of signalling network modulation and more directly by modifying the function of key proteins. In this study, we show that PTM regulation is differentially targeted at different areas of the proteome, and that cytoskeletal...... provides one of the most comprehensive sets of individual PTM site regulation data for mammalian brain tissue. This will provide a valuable resource for those wishing to perform comparisons or meta-analyses of large scale PTMomic data, as are becoming increasingly common. Furthermore, being focussed...

  16. Platelets recognize brain-specific glycolipid structures, respond to neurovascular damage and promote neuroinflammation.

    Directory of Open Access Journals (Sweden)

    Ilya Sotnikov

    Full Text Available Platelets respond to vascular damage and contribute to inflammation, but their role in the neurodegenerative diseases is unknown. We found that the systemic administration of brain lipid rafts induced a massive platelet activation and degranulation resulting in a life-threatening anaphylactic-like response in mice. Platelets were engaged by the sialated glycosphingolipids (gangliosides integrated in the rigid structures of astroglial and neuronal lipid rafts. The brain-abundant gangliosides GT1b and GQ1b were specifically recognized by the platelets and this recognition involved multiple receptors with P-selectin (CD62P playing the central role. During the neuroinflammation, platelets accumulated in the central nervous system parenchyma, acquired an activated phenotype and secreted proinflammatory factors, thereby triggering immune response cascades. This study determines a new role of platelets which directly recognize a neuronal damage and communicate with the cells of the immune system in the pathogenesis of neurodegenerative diseases.

  17. The brain imaging data structure, a format for organizing and describing outputs of neuroimaging experiments.

    Science.gov (United States)

    Gorgolewski, Krzysztof J; Auer, Tibor; Calhoun, Vince D; Craddock, R Cameron; Das, Samir; Duff, Eugene P; Flandin, Guillaume; Ghosh, Satrajit S; Glatard, Tristan; Halchenko, Yaroslav O; Handwerker, Daniel A; Hanke, Michael; Keator, David; Li, Xiangrui; Michael, Zachary; Maumet, Camille; Nichols, B Nolan; Nichols, Thomas E; Pellman, John; Poline, Jean-Baptiste; Rokem, Ariel; Schaefer, Gunnar; Sochat, Vanessa; Triplett, William; Turner, Jessica A; Varoquaux, Gaël; Poldrack, Russell A

    2016-01-01

    The development of magnetic resonance imaging (MRI) techniques has defined modern neuroimaging. Since its inception, tens of thousands of studies using techniques such as functional MRI and diffusion weighted imaging have allowed for the non-invasive study of the brain. Despite the fact that MRI is routinely used to obtain data for neuroscience research, there has been no widely adopted standard for organizing and describing the data collected in an imaging experiment. This renders sharing and reusing data (within or between labs) difficult if not impossible and unnecessarily complicates the application of automatic pipelines and quality assurance protocols. To solve this problem, we have developed the Brain Imaging Data Structure (BIDS), a standard for organizing and describing MRI datasets. The BIDS standard uses file formats compatible with existing software, unifies the majority of practices already common in the field, and captures the metadata necessary for most common data processing operations. PMID:27326542

  18. Structural and functional rejuvenation of the aged brain by an approved anti-asthmatic drug.

    Science.gov (United States)

    Marschallinger, Julia; Schäffner, Iris; Klein, Barbara; Gelfert, Renate; Rivera, Francisco J; Illes, Sebastian; Grassner, Lukas; Janssen, Maximilian; Rotheneichner, Peter; Schmuckermair, Claudia; Coras, Roland; Boccazzi, Marta; Chishty, Mansoor; Lagler, Florian B; Renic, Marija; Bauer, Hans-Christian; Singewald, Nicolas; Blümcke, Ingmar; Bogdahn, Ulrich; Couillard-Despres, Sebastien; Lie, D Chichung; Abbracchio, Maria P; Aigner, Ludwig

    2015-10-27

    As human life expectancy has improved rapidly in industrialized societies, age-related cognitive impairment presents an increasing challenge. Targeting histopathological processes that correlate with age-related cognitive declines, such as neuroinflammation, low levels of neurogenesis, disrupted blood-brain barrier and altered neuronal activity, might lead to structural and functional rejuvenation of the aged brain. Here we show that a 6-week treatment of young (4 months) and old (20 months) rats with montelukast, a marketed anti-asthmatic drug antagonizing leukotriene receptors, reduces neuroinflammation, elevates hippocampal neurogenesis and improves learning and memory in old animals. By using gene knockdown and knockout approaches, we demonstrate that the effect is mediated through inhibition of the GPR17 receptor. This work illustrates that inhibition of leukotriene receptor signalling might represent a safe and druggable target to restore cognitive functions in old individuals and paves the way for future clinical translation of leukotriene receptor inhibition for the treatment of dementias.

  19. Vocal Modification Abilities and Brain Structures in Parrots – how do they Correlate?

    DEFF Research Database (Denmark)

    Harpøth, Solveig Walløe

    Behavioral capability and related brain structures has been linked many times. It is a relationship that may vary between individuals and species, depending on for example the level of sociality. This PhD-­thesis investigates this relationship using parrots as experimental subjects. Parrots...... are among the most encephalized birds and posses excellent vocal imitation abilities. This along with their complex fission-­fusion societies and thereby dynamic use of communication make parrots unparalleled as a model system for the neurobiology behind vocal learning. This PhD thesis is based on three...... independent studies where I 1) compare the level of vocal complexity (i.e. modification of the contact call in response to playback stimuli) with the social complexity of four different parrot species, 2) correlate the vocal modification ability of parrots with a brain region involved in vocal learning, i...

  20. Structural brain abnormalities in the frontostriatal system and cerebellum in pedophilia.

    Science.gov (United States)

    Schiffer, Boris; Peschel, Thomas; Paul, Thomas; Gizewski, Elke; Forsting, Michael; Leygraf, Norbert; Schedlowski, Manfred; Krueger, Tillmann H C

    2007-11-01

    Even though previous neuropsychological studies and clinical case reports have suggested an association between pedophilia and frontocortical dysfunction, our knowledge about the neurobiological mechanisms underlying pedophilia is still fragmentary. Specifically, the brain morphology of such disorders has not yet been investigated using MR imaging techniques. Whole brain structural T1-weighted MR images from 18 pedophile patients (9 attracted to males, 9 attracted to females) and 24 healthy age-matched control subjects (12 hetero- and 12 homosexual) from a comparable socioeconomic stratum were processed by using optimized automated voxel-based morphometry within multiple linear regression analyses. Compared to the homosexual and heterosexual control subjects, pedophiles showed decreased gray matter volume in the ventral striatum (also extending into the nucl. accumbens), the orbitofrontal cortex and the cerebellum. These observations further indicate an association between frontostriatal morphometric abnormalities and pedophilia. In this respect these findings may support the hypothesis that there is a shared etiopathological mechanism in all obsessive-compulsive spectrum disorders.

  1. Bottom up modeling of the connectome: Linking structure and function in the resting brain and their changes in aging.

    OpenAIRE

    Nakagawa, Tristan T.; Jirsa, Viktor K.; Spiegler, Andreas; McIntosh, Anthony R.; Deco, Gustavo

    2013-01-01

    With the increasing availability of advanced imaging technologies, we are entering a new era of neuroscience. Detailed descriptions of the complex brain network enable us to map out a structural connectome, characterize it with graph theoretical methods, and compare it to the functional networks with increasing detail. To link these two aspects and understand how dynamics and structure interact to form functional brain networks in task and in the resting state, we use theore...

  2. Infant brain structures, executive function, and attention deficit/hyperactivity problems at preschool age. A prospective study

    OpenAIRE

    Ghassabian, Akhgar; Herba, Catherine; Roza, Sabine; Govaert, Paul; Schenk, Jacqueline; Jaddoe, Vincent; Hofman, Albert; White, Tonya; Verhulst, Frank; Tiemeier, Henning

    2013-01-01

    textabstractBackground: Neuroimaging findings have provided evidence for a relation between variations in brain structures and Attention Deficit/Hyperactivity Disorder (ADHD). However, longitudinal neuroimaging studies are typically confined to children who have already been diagnosed with ADHD. In a population-based study, we aimed to characterize the prospective association between brain structures measured during infancy and executive function and attention deficit/hyperactivity problems a...

  3. Temperature and structural changes of water clusters in vacuum due to evaporation.

    Science.gov (United States)

    Caleman, Carl; van der Spoel, David

    2006-10-21

    This paper presents a study on evaporation of pure water clusters. Molecular dynamics simulations between 20 ns and 3 micros of clusters ranging from 125 to 4096 molecules in vacuum were performed. Three different models (SPC, TIP4P, and TIP5P) were used to simulate water, starting at temperatures of 250, 275, and 300 K. We monitored the temperature, the number of hydrogen bonds, the tetrahedral order, the evaporation, the radial distribution functions, and the diffusion coefficients. The three models behave very similarly as far as temperature and evaporation are concerned. Clusters starting at a higher temperature show a higher initial evaporation rate and therefore reach the point where evaporation stop (around 240 K) sooner. The radius of the clusters is decreased by 0.16-0.22 nm after 0.5 micros (larger clusters tend to decrease their radius slightly more), which corresponds to around one evaporated molecule per nm(2). The cluster temperature seems to converge towards 215 K independent of cluster size, when starting at 275 K. We observe only small structural changes, but the clusters modeled by TIP5P show a larger percentage of molecules with low diffusion coefficient as t-->infinity, than those using the two other water models. TIP4P seems to be more structured and more hydrogen bonds are formed than in the other models as the temperature falls. The cooling rates are in good agreement with experimental results, and evaporation rates agree well with a phenomenological expression based on experimental observations. PMID:17059273

  4. Alterations in Brain Structure and Functional Connectivity in Alcohol Dependent Patients and Possible Association with Impulsivity

    Science.gov (United States)

    Dong, Yue; Ma, Mengying; Ma, Yi; Dong, Yuru; Niu, Yajuan; Jiang, Yin; Wang, Hong; Wang, Zhiyan; Wu, Liuzhen; Sun, Hongqiang; Cui, Cailian

    2016-01-01

    Background Previous studies have documented that heightened impulsivity likely contributes to the development and maintenance of alcohol use disorders. However, there is still a lack of studies that comprehensively detected the brain changes associated with abnormal impulsivity in alcohol addicts. This study was designed to investigate the alterations in brain structure and functional connectivity associated with abnormal impulsivity in alcohol dependent patients. Methods Brain structural and functional magnetic resonance imaging data as well as impulsive behavior data were collected from 20 alcohol dependent patients and 20 age- and sex-matched healthy controls respectively. Voxel-based morphometry was used to investigate the differences of grey matter volume, and tract-based spatial statistics was used to detect abnormal white matter regions between alcohol dependent patients and healthy controls. The alterations in resting-state functional connectivity in alcohol dependent patients were examined using selected brain areas with gray matter deficits as seed regions. Results Compared with healthy controls, alcohol dependent patients had significantly reduced gray matter volume in the mesocorticolimbic system including the dorsal posterior cingulate cortex, the dorsal anterior cingulate cortex, the medial prefrontal cortex, the orbitofrontal cortex and the putamen, decreased fractional anisotropy in the regions connecting the damaged grey matter areas driven by higher radial diffusivity value in the same areas and decreased resting-state functional connectivity within the reward network. Moreover, the gray matter volume of the left medial prefrontal cortex exhibited negative correlations with various impulse indices. Conclusions These findings suggest that chronic alcohol dependence could cause a complex neural changes linked to abnormal impulsivity. PMID:27575491

  5. Large-scale brain network abnormalities in Huntington's disease revealed by structural covariance.

    Science.gov (United States)

    Minkova, Lora; Eickhoff, Simon B; Abdulkadir, Ahmed; Kaller, Christoph P; Peter, Jessica; Scheller, Elisa; Lahr, Jacob; Roos, Raymund A; Durr, Alexandra; Leavitt, Blair R; Tabrizi, Sarah J; Klöppel, Stefan

    2016-01-01

    Huntington's disease (HD) is a progressive neurodegenerative disorder that can be diagnosed with certainty decades before symptom onset. Studies using structural MRI have identified grey matter (GM) loss predominantly in the striatum, but also involving various cortical areas. So far, voxel-based morphometric studies have examined each brain region in isolation and are thus unable to assess the changes in the interrelation of brain regions. Here, we examined the structural covariance in GM volumes in pre-specified motor, working memory, cognitive flexibility, and social-affective networks in 99 patients with manifest HD (mHD), 106 presymptomatic gene mutation carriers (pre-HD), and 108 healthy controls (HC). After correction for global differences in brain volume, we found that increased GM volume in one region was associated with increased GM volume in another. When statistically comparing the groups, no differences between HC and pre-HD were observed, but increased positive correlations were evident for mHD, relative to pre-HD and HC. These findings could be explained by a HD-related neuronal loss heterogeneously affecting the examined network at the pre-HD stage, which starts to dominate structural covariance globally at the manifest stage. Follow-up analyses identified structural connections between frontoparietal motor regions to be linearly modified by disease burden score (DBS). Moderator effects of disease load burden became significant at a DBS level typically associated with the onset of unequivocal HD motor signs. Together with existing findings from functional connectivity analyses, our data indicates a critical role of these frontoparietal regions for the onset of HD motor signs.

  6. High frequency of rare copy number variants affecting functionally related genes in patients with structural brain malformations

    DEFF Research Database (Denmark)

    Kariminejad, Roxana; Lind-Thomsen, Allan; Tümer, Zeynep;

    2011-01-01

    ) to investigate copy number variants (CNVs) in a cohort of 169 patients with various structural brain malformations including lissencephaly, polymicrogyria, focal cortical dysplasia, and corpus callosum agenesis. The majority of the patients had intellectual disabilities (ID) and suffered from symptomatic...... that genes involved in "axonal transport," "cation transmembrane transporter activity," and the "c-Jun N-terminal kinase (JNK) cascade" play a significant role in the etiology of brain malformations. This is to the best of our knowledge the first systematic study of CNVs in patients with structural brain...

  7. Alterations of intestinal mucosa structure and barrier function following traumatic brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    Chun-Hua Hang; Ji-Xin Shi; Jie-Shou Li; Wei Wu; Hong-Xia Yin

    2003-01-01

    AIM: Gastrointestinal dysfunction is a common complication in patients with traumatic brain injury (TBI). However, the effect of traumatic brain injury on intestinal mucosa has not been studied previously. The aim of the current study was to explore the alterations of intestinal mucosa morphology and barrier function, and to determine how rapidly the impairment of gut barrier function occurs and how long it persists following traumatic brain injury.METHODS: Male Wistar rats were randomly divided into six groups (6 rats each group) including controls without brain injury and traumatic brain injury groups at hours 3,12, 24, and 72, and on day 7. The intestinal mucosa structure was detected by histopathological examination and electron microscopy. Gut barrier dysfunction was evaluated by detecting serum endotoxin and intestinal permeability. The level of serum endotoxin and intestinal permeability was measured by using chromogenic limulus amebocyte lysate and lactulose/mannitol (L/M) ratio, respectively.RESULTS: After traumatic brain injury, the histopathological alterations of gut mucosa occurred rapidly as early as 3 hours and progressed to a serious state, including shedding of epithelial cells, fracture of villi, focal ulcer, fusion of adjacent villi, dilation of central chyle duct, mucosal atrophy,and vascular dilation, congestion and edema in the villous interstitium and lamina propria. Apoptosis of epithelial cells,fracture and sparseness of microvilli, loss of tight junction between enterocytes, damage of mitochondria and endoplasm, were found by electron microscopy. The villous height, crypt depth and surface area in jejunum decreased progressively with the time of brain injury. As compared with that of control group (183.7±41.8 EU/L), serum endotoxin level was signnificantly increased at 3, 12, and 24 hours following TBI (434.8±54.9 EU/L, 324.2±61.7 EU/L and 303.3±60.2 EU/L, respectively), and peaked at 72 hours (560.5±76.2 EU/L), then declined on day 7

  8. Efficiency enhancement due to self-organization of nano-structures in Cd(S, Te) solar cell material

    Science.gov (United States)

    Sato, Kazunori; Katayama-Yoshida, Hiroshi

    2014-03-01

    CdTe is one of the most important solar cell materials. Its energy gap is 1.44 eV, which is ideal for solar cell application. So far, conversion efficiency of 18.3 percent has been realized, but it is lower than the Shockley-Queisser limit. In this paper, we propose computational materials design for enhancing conversion efficiency by using self-organization in Cd(Te, S) alloy semiconductor. Firstly, we performed cluster expansion of total energy of the Cd(Te, S) system and simulated self-organization of nano-structures in Cd(Te, S) by using Monte Carlo method. It is found that layered structure becomes stable by applying strain during the crystal growth. The electronic structure of the self-organized layered structure was calculated by using the hybrid method (HSE06) implemented in the VASP code to derive optical absorption coefficient. By using the calculated absorption coefficient the efficiency limit was derived based on the Shockley-Queisser theory. It is shown that the efficiency limit does not change so much due to the nano-structure formation. However, our calculation shows spatial separation between photo-generated electrons and holes. This might enhance the efficiency due to the suppression of recombination.

  9. Modified structural and frequency dependent impedance formalism of nanoscale BaTiO3 due to Tb inclusion

    Science.gov (United States)

    Borah, Manjit; Mohanta, Dambarudhar

    2016-05-01

    We report the effect of Tb-doping on the structural and high frequency impedance response of the nanoscale BaTiO3 (BT) systems. While exhibiting a mixed phase crystal structure, the nano-BT systems are found to evolve with edges, and facets. The interplanar spacing of crystal lattice fringes is ~0.25 nm. The Cole-Cole plots, in the impedance formalism, have demonstrated semicircles which are the characteristic feature of grain boundary resistance of several MΩ. A lowering of ac conductivity with doping was believed to be due to the manifestation of oxygen vacancies and vacancy ordering.

  10. Mitochondrial free radical overproduction due to respiratory chain impairment in the brain of a mouse model of Rett syndrome: protective effect of CNF1.

    Science.gov (United States)

    De Filippis, Bianca; Valenti, Daniela; de Bari, Lidia; De Rasmo, Domenico; Musto, Mattia; Fabbri, Alessia; Ricceri, Laura; Fiorentini, Carla; Laviola, Giovanni; Vacca, Rosa Anna

    2015-06-01

    Rett syndrome (RTT) is a pervasive neurodevelopmental disorder mainly caused by mutations in the X-linked MECP2 gene associated with severe intellectual disability, movement disorders, and autistic-like behaviors. Its pathogenesis remains mostly not understood and no effective therapy is available. High circulating levels of oxidative stress markers in patients and the occurrence of oxidative brain damage in MeCP2-deficient mouse models suggest the involvement of oxidative stress in RTT pathogenesis. However, the molecular mechanism and the origin of the oxidative stress have not been elucidated. Here we demonstrate that a redox imbalance arises from aberrant mitochondrial functionality in the brain of MeCP2-308 heterozygous female mice, a condition that more closely recapitulates that of RTT patients. The marked increase in the rate of hydrogen peroxide generation in the brain of RTT mice seems mainly produced by the dysfunctional complex II of the mitochondrial respiratory chain. In addition, both membrane potential generation and mitochondrial ATP synthesis are decreased in RTT mouse brains when succinate, the complex II respiratory substrate, is used as an energy source. Respiratory chain impairment is brain area specific, owing to a decrease in either cAMP-dependent phosphorylation or protein levels of specific complex subunits. Further, we investigated whether the treatment of RTT mice with the bacterial protein CNF1, previously reported to ameliorate the neurobehavioral phenotype and brain bioenergetic markers in an RTT mouse model, exerts specific effects on brain mitochondrial function and consequently on hydrogen peroxide production. In RTT brains treated with CNF1, we observed the reactivation of respiratory chain complexes, the rescue of mitochondrial functionality, and the prevention of brain hydrogen peroxide overproduction. These results provide definitive evidence of mitochondrial reactive oxygen species overproduction in RTT mouse brain and

  11. Investigation of the structure change of atomic shells due to uranium ionization by the Dirac-Fock-Slater method

    International Nuclear Information System (INIS)

    The influence of outer vacancies in the atomic shells of uranium on the atomic shell structure is claculated by the Dirac-Fock-Slater method. It is found out that the energy of the X-ray transitions increases due to the detachment of the electrons with the lowest binding energies. The electron detachment from the subshells of the 4f level gives rise to negative energy shifts of the X-ray transitions.(author)

  12. Exploring the brain's structural connectome: A quantitative stroke lesion-dysfunction mapping study.

    Science.gov (United States)

    Kuceyeski, Amy; Navi, Babak B; Kamel, Hooman; Relkin, Norman; Villanueva, Mark; Raj, Ashish; Toglia, Joan; O'Dell, Michael; Iadecola, Costantino

    2015-06-01

    The aim of this work was to quantitatively model cross-sectional relationships between structural connectome disruptions caused by cerebral infarction and measures of clinical performance. Imaging biomarkers of 41 ischemic stroke patients (72.0 ± 12.0 years, 20 female) were related to their baseline performance in 18 cognitive, physical and daily life activity assessments. Individual estimates of structural connectivity disruption in gray matter regions were computed using the Change in Connectivity (ChaCo) score. ChaCo scores were utilized because they can be calculated using routinely collected clinical magnetic resonance imagings. Partial Least Squares Regression (PLSR) was used to predict various acute impairment and activity measures from ChaCo scores and patient demographics. Statistical methods of cross-validation, bootstrapping and multiple comparisons correction were implemented to minimize over-fitting and Type I errors. Multiple linear regression models based on lesion volume and lateralization information were constructed for comparison. All models based on connectivity disruption had lower Akaike Information Criterion and almost all had better goodness-of-fit values (R(2) : 0.26-0.92) than models based on lesion characteristics (R(2) : 0.06-0.50). Confidence intervals of PLSR coefficients identified brain regions important in predicting each clinical assessment. Appropriate mapping of eloquent functions, that is, language and motor, and replication of results across pathologies provided validation of this method. Models of complex functions provided new insights into brain-behavior relationships. In addition to the potential applications in prognostication and rehabilitation development, this quantitative approach provides insight into the structural networks underlying complex functions like activities of daily living and cognition. Quantitative analysis of big data will be invaluable in understanding complex brain-behavior relationships. PMID

  13. Exercise challenge in Gulf War Illness reveals two subgroups with altered brain structure and function.

    Directory of Open Access Journals (Sweden)

    Rakib U Rayhan

    Full Text Available Nearly 30% of the approximately 700,000 military personnel who served in Operation Desert Storm (1990-1991 have developed Gulf War Illness, a condition that presents with symptoms such as cognitive impairment, autonomic dysfunction, debilitating fatigue and chronic widespread pain that implicate the central nervous system. A hallmark complaint of subjects with Gulf War Illness is post-exertional malaise; defined as an exacerbation of symptoms following physical and/or mental effort. To study the causal relationship between exercise, the brain, and changes in symptoms, 28 Gulf War veterans and 10 controls completed an fMRI scan before and after two exercise stress tests to investigate serial changes in pain, autonomic function, and working memory. Exercise induced two clinical Gulf War Illness subgroups. One subgroup presented with orthostatic tachycardia (n = 10. This phenotype correlated with brainstem atrophy, baseline working memory compensation in the cerebellar vermis, and subsequent loss of compensation after exercise. The other subgroup developed exercise induced hyperalgesia (n = 18 that was associated with cortical atrophy and baseline working memory compensation in the basal ganglia. Alterations in cognition, brain structure, and symptoms were absent in controls. Our novel findings may provide an understanding of the relationship between the brain and post-exertional malaise in Gulf War Illness.

  14. Functional and Structural Brain Plasticity Enhanced by Motor and Cognitive Rehabilitation in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Luca Prosperini

    2015-01-01

    Full Text Available Rehabilitation is recognized to be important in ameliorating motor and cognitive functions, reducing disease burden, and improving quality of life in patients with multiple sclerosis (MS. In this systematic review, we summarize the existing evidences that motor and cognitive rehabilitation may enhance functional and structural brain plasticity in patients with MS, as assessed by means of the most advanced neuroimaging techniques, including diffusion tensor imaging and task-related and resting-state functional magnetic resonance imaging (MRI. In most cases, the rehabilitation program was based on computer-assisted/video game exercises performed in either an outpatient or home setting. Despite their heterogeneity, all the included studies describe changes in white matter microarchitecture, in task-related activation, and/or in functional connectivity following both task-oriented and selective training. When explored, relevant correlation between improved function and MRI-detected brain changes was often found, supporting the hypothesis that training-induced brain plasticity is specifically linked to the trained domain. Small sample sizes, lack of randomization and/or an active control group, as well as missed relationship between MRI-detected changes and clinical performance, are the major drawbacks of the selected studies. Knowledge gaps in this field of research are also discussed to provide a framework for future investigations.

  15. Functional and Structural Brain Plasticity Enhanced by Motor and Cognitive Rehabilitation in Multiple Sclerosis

    Science.gov (United States)

    Prosperini, Luca; Piattella, Maria Cristina

    2015-01-01

    Rehabilitation is recognized to be important in ameliorating motor and cognitive functions, reducing disease burden, and improving quality of life in patients with multiple sclerosis (MS). In this systematic review, we summarize the existing evidences that motor and cognitive rehabilitation may enhance functional and structural brain plasticity in patients with MS, as assessed by means of the most advanced neuroimaging techniques, including diffusion tensor imaging and task-related and resting-state functional magnetic resonance imaging (MRI). In most cases, the rehabilitation program was based on computer-assisted/video game exercises performed in either an outpatient or home setting. Despite their heterogeneity, all the included studies describe changes in white matter microarchitecture, in task-related activation, and/or in functional connectivity following both task-oriented and selective training. When explored, relevant correlation between improved function and MRI-detected brain changes was often found, supporting the hypothesis that training-induced brain plasticity is specifically linked to the trained domain. Small sample sizes, lack of randomization and/or an active control group, as well as missed relationship between MRI-detected changes and clinical performance, are the major drawbacks of the selected studies. Knowledge gaps in this field of research are also discussed to provide a framework for future investigations. PMID:26064692

  16. The brain structure and spontaneous activity baseline of the behavioral bias in trait anxiety.

    Science.gov (United States)

    Yin, Ping; Zhang, Meng; Hou, Xin; Tan, Yafei; Fu, Yixiao; Qiu, Jiang

    2016-10-01

    Individuals with trait anxiety are often considered to be predisposed to psychiatric disorders. However, there is great heterogeneity in the development of psychiatric disorders in this group of people and the nature of the trait anxiety is still unclear. So, we decided to explore the correlations of brain structure and brain activity with trait anxiety in normal individuals. Specifically, we investigated the correlations between trait anxiety and regional grey matter volume (rGMV) and regional BOLD, using the Amplitude of Low Frequency Fluctuations (ALFF) as an index in 382 university students. The results showed that the level of trait anxiety was negatively correlated with rGMV in the right middle occipital gyrus. This result indicates that individuals with high trait anxiety tend to have less image processing on conscious level. Furthermore, we found that trait anxiety was positively correlated with the ALFF in the bilateral superior frontal gyrus and the right supplementary motor area, and negatively correlated with the ALFF in the cerebellum and the thalamus. These results indicate that individuals with high trait anxiety may be more sensitive to relationships and sensory information. Overall, this study's findings suggest that individuals with high trait anxiety have attenuated image processing on the conscious level, and exhibit stronger induced sensibility and over-processing of relationships, which is a brain imaging precondition for psychiatric disorders. PMID:27340090

  17. Exercise challenge in Gulf War Illness reveals two subgroups with altered brain structure and function.

    Science.gov (United States)

    Rayhan, Rakib U; Stevens, Benson W; Raksit, Megna P; Ripple, Joshua A; Timbol, Christian R; Adewuyi, Oluwatoyin; VanMeter, John W; Baraniuk, James N

    2013-01-01

    Nearly 30% of the approximately 700,000 military personnel who served in Operation Desert Storm (1990-1991) have developed Gulf War Illness, a condition that presents with symptoms such as cognitive impairment, autonomic dysfunction, debilitating fatigue and chronic widespread pain that implicate the central nervous system. A hallmark complaint of subjects with Gulf War Illness is post-exertional malaise; defined as an exacerbation of symptoms following physical and/or mental effort. To study the causal relationship between exercise, the brain, and changes in symptoms, 28 Gulf War veterans and 10 controls completed an fMRI scan before and after two exercise stress tests to investigate serial changes in pain, autonomic function, and working memory. Exercise induced two clinical Gulf War Illness subgroups. One subgroup presented with orthostatic tachycardia (n = 10). This phenotype correlated with brainstem atrophy, baseline working memory compensation in the cerebellar vermis, and subsequent loss of compensation after exercise. The other subgroup developed exercise induced hyperalgesia (n = 18) that was associated with cortical atrophy and baseline working memory compensation in the basal ganglia. Alterations in cognition, brain structure, and symptoms were absent in controls. Our novel findings may provide an understanding of the relationship between the brain and post-exertional malaise in Gulf War Illness.

  18. A case-control study of brain structure and behavioral characteristics in 47,XXX syndrome.

    Science.gov (United States)

    Lenroot, R K; Blumenthal, J D; Wallace, G L; Clasen, L S; Lee, N R; Giedd, J N

    2014-11-01

    Trisomy X, the presence of an extra X chromosome in females (47,XXX), is a relatively common but under-recognized chromosomal disorder associated with characteristic cognitive and behavioral features of varying severity. The objective of this study was to determine whether there were neuroanatomical differences in girls with Trisomy X that could relate to cognitive and behavioral differences characteristic of the disorder during childhood and adolescence. MRI scans were obtained on 35 girls with Trisomy X (mean age 11.4, SD 5.5) and 70 age- and sex-matched healthy controls. Cognitive and behavioral testing was also performed. Trisomy X girls underwent a semi-structured psychiatric interview. Regional brain volumes and cortical thickness were compared between the two groups. Total brain volume was significantly decreased in subjects with Trisomy X, as were all regional volumes with the exception of parietal gray matter. Differences in cortical thickness had a mixed pattern. The subjects with Trisomy X had thicker cortex in bilateral medial prefrontal cortex and right medial temporal lobe, but decreased cortical thickness in both lateral temporal lobes. The most common psychiatric disorders present in this sample of Trisomy X girls included anxiety disorders (40%), attention-deficit disorder (17%) and depressive disorders (11%). The most strongly affected brain regions are consistent with phenotypic characteristics such as language delay, poor executive function and heightened anxiety previously described in population-based studies of Trisomy X and also found in our sample.

  19. Rectified motion in an asymmetrically structured channel due to induced-charge electrokinetic and thermo-kinetic phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Sugioka, Hideyuki, E-mail: hsugioka@shinshu-u.ac.jp [Frontier Research Center, Canon Inc. 30-2, Shimomaruko 3-chome, Ohta-ku, Tokyo 146-8501, Japan and Department of Mechanical Systems Engineering, Shinshu University 4-17-1 Wakasato, Nagano 380-8553 (Japan)

    2016-02-15

    It would be advantageous to move fluid by the gradient of random thermal noises that are omnipresent in the natural world. To achieve this motion, we propose a rectifier that uses a thermal noise along with induced-charge electroosmosis and electrophoresis (ICEO and ICEP) around a metal post cylinder in an asymmetrically structured channel and numerically examine its rectification performance. By the boundary element method combined with the thin double layer approximation, we find that rectified motion occurs in the asymmetrically structured channel due to ICEO and ICEP. Further, by thermodynamical and equivalent circuit methods, we discuss a thermal voltage that drives a rectifier consisting of a fluidic channel of an electrolyte and an impedance as a noise source. Our calculations show that fluid can be moved in the asymmetrically structured channel by the fluctuation of electric fields due to a thermal noise only when there is a temperature difference. In addition, our simple noise argument provides a different perspective for the thermo-kinetic phenomena (around a metal post) which was predicted based on the electrolyte Seebeck effect in our previous paper [H. Sugioka, “Nonlinear thermokinetic phenomena due to the Seebeck effect,” Langmuir 30, 8621 (2014)].

  20. Effects of aluminum and other cations on the structure of brain and liver chromatin.

    Science.gov (United States)

    Walker, P R; LeBlanc, J; Sikorska, M

    1989-05-01

    The reactivity of aluminum and several other divalent and trivalent metallic cations toward chromatin from rat brain and liver has been investigated. Two criteria are used to determine the relative reactivity of these cations toward chromatin. The first involves the ability of the ions to compact the chromatin fibers to the point where chromatin precipitates. The second criterion measures the ability of cations to interfere with the accessibility of exogenous structural probes (nucleases) to chromatin. Of the divalent cations tested, nickel, cobalt, zinc, cadmium, and mercury were the most reactive toward chromatin, on the basis of their ability to induce precipitation of chromatin in the micromolar concentration range. The divalent cations magnesium, calcium, copper, strontium, and barium were much less effective, although all cations precipitate chromatin if their concentration is increased. Of the trivalent cations tested, aluminum, indium, and gallium were very effective precipitants, whereas iron and scandium were without effect at the concentrations tested. Of all the cations tested, aluminum was the most reactive. Aluminum's ability to alter the structure of chromatin was investigated further by testing its ability to interfere with nuclease accessibility. This test confirmed that aluminum does induce considerable changes in chromatin structure at micromolar concentrations. Furthermore, chromatin from cortical areas of the brain was much more sensitive to aluminum than chromatin from liver. These results are discussed in light of the known toxicity of these cations, with particular emphasis on the possible role of aluminum in Alzheimer's disease. PMID:2752000

  1. Structural and Functional Brain Correlates of Cognitive Impairment in Euthymic Patients with Bipolar Disorder

    Science.gov (United States)

    Goikolea, José M.; Bonnin, Caterina M.; Sarró, Salvador; Segura, Barbara; Amann, Benedikt L.; Monté, Gemma C.; Moro, Noemi; Fernandez-Corcuera, Paloma; Maristany, Teresa; Salvador, Raymond; Vieta, Eduard; Pomarol-Clotet, Edith; McKenna, Peter J.

    2016-01-01

    Introduction Cognitive impairment in the euthymic phase is a well-established finding in bipolar disorder. However, its brain structural and/or functional correlates are uncertain. Methods Thirty-three euthymic bipolar patients with preserved memory and executive function and 28 euthymic bipolar patients with significant memory and/or executive impairment, as defined using two test batteries, the Rivermead Behavioural Memory Test (RBMT) and the Behavioural Assessment of the Dysexecutive Syndrome (BADS), plus 28 healthy controls underwent structural MRI using voxel-based morphometry (VBM). Twenty-seven of the cognitively preserved patients, 23 of the cognitively impaired patients and 28 controls also underwent fMRI during performance of the n-back working memory task. Results No clusters of grey or white matter volume difference were found between the two patient groups. During n-back performance, the cognitively impaired patients showed hypoactivation compared to the cognitively preserved patients in a circumscribed region in the right dorsolateral prefrontal cortex. Both patient groups showed failure of de-activation in the medial frontal cortex compared to the healthy controls. Conclusions Cognitive impairment in euthymic bipolar patients appears from this study to be unrelated to structural brain abnormality, but there was some evidence for an association with altered prefrontal function. PMID:27448153

  2. Functional and structural brain correlates of risk for major depression in children with familial depression

    Directory of Open Access Journals (Sweden)

    Xiaoqian J. Chai

    2015-01-01

    Full Text Available Despite growing evidence for atypical amygdala function and structure in major depression, it remains uncertain as to whether these brain differences reflect the clinical state of depression or neurobiological traits that predispose individuals to major depression. We examined function and structure of the amygdala and associated areas in a group of unaffected children of depressed parents (at-risk group and a group of children of parents without a history of major depression (control group. Compared to the control group, the at-risk group showed increased activation to fearful relative to neutral facial expressions in the amygdala and multiple cortical regions, and decreased activation to happy relative to neutral facial expressions in the anterior cingulate cortex and supramarginal gyrus. At-risk children also exhibited reduced amygdala volume. The extensive hyperactivation to negative facial expressions and hypoactivation to positive facial expressions in at-risk children are consistent with behavioral evidence that risk for major depression involves a bias to attend to negative information. These functional and structural brain differences between at-risk children and controls suggest that there are trait neurobiological underpinnings of risk for major depression.

  3. Chondroitin Sulfate Proteoglycans: Structure-Function Relationship with Implication in Neural Development and Brain Disorders

    Directory of Open Access Journals (Sweden)

    Speranta Avram

    2014-01-01

    Full Text Available Chondroitin sulfate proteoglycans (CSPGs are extracellular matrix components that contain two structural parts with distinct functions: a protein core and glycosaminoglycan (GAG side chains. CSPGs are known to be involved in important cell processes like cell adhesion and growth, receptor binding, or cell migration. It is recognized that the presence of CSPGs is critical in neuronal growth mechanisms including axon guidance following injury of nervous system components such as spinal cord and brain. CSPGs are upregulated in the central nervous system after injury and participate in the inhibition of axon regeneration mainly through their GAG side chains. Recently, it was shown that some CSPGs members like aggrecan, versican, and neurocan were strongly involved in brain disorders like bipolar disorder (BD, schizophrenia, and ADHD. In this paper, we present the chemical structure-biological functions relationship of CSPGs, both in health state and in genetic disorders, addressing methods represented by genome-wide and crystallographic data as well as molecular modeling and quantitative structure-activity relationship.

  4. Structure Expression and Function of kynurenine Aminotransferases in Human and Rodent Brains

    Energy Technology Data Exchange (ETDEWEB)

    Q Han; T Cai; D Tagle; J Li

    2011-12-31

    Kynurenine aminotransferases (KATs) catalyze the synthesis of kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D: -aspartate and alpha 7-nicotinic acetylcholine receptors. Abnormal KYNA levels in human brains are implicated in the pathophysiology of schizophrenia, Alzheimer's disease, and other neurological disorders. Four KATs have been reported in mammalian brains, KAT I/glutamine transaminase K/cysteine conjugate beta-lyase 1, KAT II/aminoadipate aminotransferase, KAT III/cysteine conjugate beta-lyase 2, and KAT IV/glutamic-oxaloacetic transaminase 2/mitochondrial aspartate aminotransferase. KAT II has a striking tertiary structure in N-terminal part and forms a new subgroup in fold type I aminotransferases, which has been classified as subgroup Iepsilon. Knowledge regarding KATs is vast and complex; therefore, this review is focused on recent important progress of their gene characterization, physiological and biochemical function, and structural properties. The biochemical differences of four KATs, specific enzyme activity assays, and the structural insights into the mechanism of catalysis and inhibition of these enzymes are discussed.

  5. To cut or not to cut? Assessing the modular structure of brain networks.

    Science.gov (United States)

    Chang, Yu-Teng; Pantazis, Dimitrios; Leahy, Richard M

    2014-05-01

    A wealth of methods has been developed to identify natural divisions of brain networks into groups or modules, with one of the most prominent being modularity. Compared with the popularity of methods to detect community structure, only a few methods exist to statistically control for spurious modules, relying almost exclusively on resampling techniques. It is well known that even random networks can exhibit high modularity because of incidental concentration of edges, even though they have no underlying organizational structure. Consequently, interpretation of community structure is confounded by the lack of principled and computationally tractable approaches to statistically control for spurious modules. In this paper we show that the modularity of random networks follows a transformed version of the Tracy-Widom distribution, providing for the first time a link between module detection and random matrix theory. We compute parametric formulas for the distribution of modularity for random networks as a function of network size and edge variance, and show that we can efficiently control for false positives in brain and other real-world networks.

  6. A diagnosis model for early Tourette syndrome children based on brain structural network characteristics

    Science.gov (United States)

    Wen, Hongwei; Liu, Yue; Wang, Jieqiong; Zhang, Jishui; Peng, Yun; He, Huiguang

    2016-03-01

    Tourette syndrome (TS) is a childhood-onset neurobehavioral disorder characterized by the presence of multiple motor and vocal tics. Tic generation has been linked to disturbed networks of brain areas involved in planning, controlling and execution of action. The aim of our work is to select topological characteristics of structural network which were most efficient for estimating the classification models to identify early TS children. Here we employed the diffusion tensor imaging (DTI) and deterministic tractography to construct the structural networks of 44 TS children and 48 age and gender matched healthy children. We calculated four different connection matrices (fiber number, mean FA, averaged fiber length weighted and binary matrices) and then applied graph theoretical methods to extract the regional nodal characteristics of structural network. For each weighted or binary network, nodal degree, nodal efficiency and nodal betweenness were selected as features. Support Vector Machine Recursive Feature Extraction (SVM-RFE) algorithm was used to estimate the best feature subset for classification. The accuracy of 88.26% evaluated by a nested cross validation was achieved on combing best feature subset of each network characteristic. The identified discriminative brain nodes mostly located in the basal ganglia and frontal cortico-cortical networks involved in TS children which was associated with tic severity. Our study holds promise for early identification and predicting prognosis of TS children.

  7. Radio Tomography of Ionospheric Structures (probably) due to Underground-Surface-Atmosphere-Ionosphere Coupling

    Science.gov (United States)

    Kunitsyn, V.; Nesterov, I.; Andreeva, E.; Rekenthaler, D. A.

    2012-12-01

    . The single-point measurements (by ionosondes or by isolated receivers) are not amenable to unambiguous interpretation; based on these data, it is impossible to distinguish the contribution of USAI coupling from the ionospheric effects induced by the "ordinary" impacts (the Sun, the solar wind, geomagnetic perturbations, galactic cosmic rays, etc.). In order to localize sources of the ionospheric disturbances, the geophysicist needs information on the spatial structure and dynamics of the ionospheric perturbations. This information (2D-4D RT images) is optimally provided by RT methods. We present examples of the ionospheric disturbances caused by EQs as well as the ionospheric precursors of these EQs in the form of specific ionospheric irregularities: AGW- and soliton-like wave disturbances, which we identified using RT methods. Based on the results of the RT studies in the Alaska and Taiwan regions, we have detected several dozen AGW-related precursors of EQs. These data allow us to attempt to locate the source of these perturbations. We discuss the possibilities and prospects of further research aimed at identifying and analyzing precursors of EQs and establishing the mechanisms of USAI coupling. We are grateful to Northwest Research Associates, Inc., and Dr. L.-C.Tsai for providing raw RT data for Alaska and Taiwan.

  8. Factor structure and item level psychometrics of the Social Problem Solving Inventory-Revised: Short Form in traumatic brain injury.

    Science.gov (United States)

    Li, Chih-Ying; Waid-Ebbs, Julia; Velozo, Craig A; Heaton, Shelley C

    2016-01-01

    Social problem-solving deficits characterise individuals with traumatic brain injury (TBI), and poor social problem solving interferes with daily functioning and productive lifestyles. Therefore, it is of vital importance to use the appropriate instrument to identify deficits in social problem solving for individuals with TBI. This study investigates factor structure and item-level psychometrics of the Social Problem Solving Inventory-Revised: Short Form (SPSI-R:S), for adults with moderate and severe TBI. Secondary analysis of 90 adults with moderate and severe TBI who completed the SPSI-R:S was performed. An exploratory factor analysis (EFA), principal components analysis (PCA) and Rasch analysis examined the factor structure and item-level psychometrics of the SPSI-R:S. The EFA showed three dominant factors, with positively worded items represented as the most definite factor. The other two factors are negative problem-solving orientation and skills; and negative problem-solving emotion. Rasch analyses confirmed the three factors are each unidimensional constructs. It was concluded that the total score interpretability of the SPSI-R:S may be challenging due to the multidimensional structure of the total measure. Instead, we propose using three separate SPSI-R:S subscores to measure social problem solving for the TBI population.

  9. In vivo study about specific captation of 125 I-insulin by rat brain structures

    International Nuclear Information System (INIS)

    The specific captation of 125 I-insulin was evaluated by brain structures, as olfactory bulbous, hypothalamus and cerebellum in rats, from in vivo experiences that including two different aspects: captation measure of 125 I-insulin after the intravenous injection of the labelled hormone, in fed rats and in rats with 48 h of fast or convulsion, procedure by the pentylene tetrazole; captation measure of 125 I-insulin after intra-cerebral-ventricular injection of the labelled hormone in fed rats. (C.G.C.)

  10. Relationship between AQP4 expression and structural damage to the blood-brain barrier at early stages of traumatic brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    LU Hong; LEI Xiao-yan; HU Hui; HE Zhan-ping

    2013-01-01

    Background Although some studies have reported that aquaporin-4 (AQP4) plays an important role in the brain edema after traumatic brain injury (TBI),little is known about the AQP4 expression in the early stage of TBI,or about the correlation between the structural damage to the blood-brain barrier (BBB) and angioedema.The aim of this project was to investigate the relationship between AQP4 expression and damage to the BBB at early stages of TBI.Methods One hundred and twenty healthy adult Wistar rats were randomly divided into two greups:sham operation group (SO) and TBI group.The TBI group was divided into five sub-groups according to the different time intervals:1,3,6,12,and 24 hours.The brains of the animals were taken out at different time points after TBI to measure brain water content.The cerebral edema and BBB changes in structure were examined with an optical microscopy (OM) and transmission electron microscopy (TEM),and the IgG content and AQP4 protein expression in traumatic brain tissue were determined by means of immunohistochemistry and Western blotting.The data were analyzed with SPSS 13.0statistical software.Results In the SO greup,tissue was negative for IgG,and there were no abnormalities in brain water content or AQP4 expression.In the TBI group,brain water content significantly increased at 6 hours and peaked at 24 hours following injury.IgG expression significantly increased from 1 to 6 hours following injury,and remained at a high level at 24 hours.Pathological observation revealed BBB damage at 1 hour following injury.Angioedema appeared at 1 hour,was gradually aggravated,and became obvious at 6 hours.Intracellular edema occurred at 3 hours,with the presence of large glial cell bodies and mitochondrial swelling.These phenomena were aggravated with time and became obvious at 12 hours.In addition,microglial proliferation was visible at 24 hours.AQP4 protein expression were reduced at 1 hour,lowest at 6 hours,and began to increase at 12 hours

  11. Extreme learning machine-based classification of ADHD using brain structural MRI data.

    Directory of Open Access Journals (Sweden)

    Xiaolong Peng

    Full Text Available BACKGROUND: Effective and accurate diagnosis of attention-deficit/hyperactivity disorder (ADHD is currently of significant interest. ADHD has been associated with multiple cortical features from structural MRI data. However, most existing learning algorithms for ADHD identification contain obvious defects, such as time-consuming training, parameters selection, etc. The aims of this study were as follows: (1 Propose an ADHD classification model using the extreme learning machine (ELM algorithm for automatic, efficient and objective clinical ADHD diagnosis. (2 Assess the computational efficiency and the effect of sample size on both ELM and support vector machine (SVM methods and analyze which brain segments are involved in ADHD. METHODS: High-resolution three-dimensional MR images were acquired from 55 ADHD subjects and 55 healthy controls. Multiple brain measures (cortical thickness, etc. were calculated using a fully automated procedure in the FreeSurfer software package. In total, 340 cortical features were automatically extracted from 68 brain segments with 5 basic cortical features. F-score and SFS methods were adopted to select the optimal features for ADHD classification. Both ELM and SVM were evaluated for classification accuracy using leave-one-out cross-validation. RESULTS: We achieved ADHD prediction accuracies of 90.18% for ELM using eleven combined features, 84.73% for SVM-Linear and 86.55% for SVM-RBF. Our results show that ELM has better computational efficiency and is more robust as sample size changes than is SVM for ADHD classification. The most pronounced differences between ADHD and healthy subjects were observed in the frontal lobe, temporal lobe, occipital lobe and insular. CONCLUSION: Our ELM-based algorithm for ADHD diagnosis performs considerably better than the traditional SVM algorithm. This result suggests that ELM may be used for the clinical diagnosis of ADHD and the investigation of different brain diseases.

  12. Structural changes of small amplitude kinetic Alfvén solitary waves due to second-order corrections

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Cheong R. [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)

    2015-10-15

    The structural changes of kinetic Alfvén solitary waves (KASWs) due to higher-order terms are investigated. While the first-order differential equation for KASWs provides the dispersion relation for kinetic Alfvén waves, the second-order differential equation describes the structural changes of the solitary waves due to higher-order nonlinearity. The reductive perturbation method is used to obtain the second-order and third-order partial differential equations; then, Kodama and Taniuti's technique [J. Phys. Soc. Jpn. 45, 298 (1978)] is applied in order to remove the secularities in the third-order differential equations and derive a linear second-order inhomogeneous differential equation. The solution to this new second-order equation indicates that, as the amplitude increases, the hump-type Korteweg-de Vries solution is concentrated more around the center position of the soliton and that dip-type structures form near the two edges of the soliton. This result has a close relationship with the interpretation of the complex KASW structures observed in space with satellites.

  13. Structural, chemical surface and transport modifications of regenerated cellulose dense membranes due to low-dose {gamma}-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, M.I. [Grupo de Caracterizacion Electrocinetica en Membranas e Interfases, Departamento de Fisica Aplicada I, Facultad de Ciencias, Universidad de Malaga, E-29071 Malaga (Spain); Heredia-Guerrero, J.A., E-mail: jose.alejandro@icmse.csic.es [Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Avda, Americo Vespuccio 49, 41092 Sevilla (Spain); Galan, P. [Grupo de Caracterizacion Electrocinetica en Membranas e Interfases, Departamento de Fisica Aplicada I, Facultad de Ciencias, Universidad de Malaga, E-29071 Malaga (Spain); Benitez, J.J. [Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Avda, Americo Vespuccio 49, 41092 Sevilla (Spain); Benavente, J. [Grupo de Caracterizacion Electrocinetica en Membranas e Interfases, Departamento de Fisica Aplicada I, Facultad de Ciencias, Universidad de Malaga, E-29071 Malaga (Spain)

    2011-04-15

    Research highlights: {yields} Low dose {gamma}-radiation causes slight structural, chemical and morphological changes on regenerated cellulose films. {yields} Induced structural changes increase the fragility of irradiated films. {yields} Structural modifications reduce ion permeability of films. - Abstract: Modifications caused in commercial dense regenerated cellulose (RC) flat membranes by low-dose {gamma}-irradiation (average photons energy of 1.23 MeV) are studied. Slight structural, chemical and morphological surface changes due to irradiation in three films with different RC content were determined by ATR-FTIR, XRD, XPS and AFM. Also, the alteration of their mechanical elasticity has been studied. Modification of membrane performance was determined from solute diffusion coefficient and effective membrane fixed charge concentration obtained from NaCl diffusion measurements. Induced structural changes defining new and effective fracture propagation directions are considered to be responsible for the increase of fragility of irradiated RC membranes. The same structural changes are proposed to explain the reduction of the membrane ion permeability through a mechanism involving either ion pathways elongation and/or blocking.

  14. Common genetic variation near MC4R has a sex-specific impact on human brain structure and eating behavior.

    Directory of Open Access Journals (Sweden)

    Annette Horstmann

    Full Text Available Obesity is associated with genetic and environmental factors but the underlying mechanisms remain poorly understood. Recent genome-wide association studies (GWAS identified obesity- and type 2 diabetes-associated genetic variants located within or near genes that modulate brain activity and development. Among the top hits is rs17782313 near MC4R, encoding for the melanocortin-4-receptor, which is expressed in brain regions that regulate eating. Here, we hypothesized rs17782313-associated changes in human brain regions that regulate eating behavior. Therefore, we examined effects of common variants at rs17782313 near MC4R on brain structure and eating behavior. Only in female homozygous carriers of the risk allele we found significant increases of gray matter volume (GMV in the right amygdala, a region known to influence eating behavior, and the right hippocampus, a structure crucial for memory formation and learning. Further, we found bilateral increases in medial orbitofrontal cortex, a multimodal brain structure encoding the subjective value of reinforcers, and bilateral prefrontal cortex, a higher order regulation area. There was no association between rs17782313 and brain structure in men. Moreover, among female subjects only, we observed a significant increase of 'disinhibition', and, more specifically, on 'emotional eating' scores of the Three Factor Eating Questionnaire in carriers of the variant rs17782313's risk allele. These findings suggest that rs17782313's effect on eating behavior is mediated by central mechanisms and that these effects are sex-specific.

  15. Revascularization Using an Extracorporeal Pump for the Treatment of Cerebral Embolism in the Acute Stage: For Protection of the Brain Tissue from Irreversible Change due to Cerebral Embolism

    OpenAIRE

    Sonobe, M.; Nakai, Y.; Matsumaru, Y.; Sugita, K.

    2001-01-01

    Object. For patients with cerebral embolism, we are using an extracorporeal pump to revascularize the more peripheral brain tissues far from the thrombus, proceeding the microcatheter beyond the thrombus, and dissolving the thrombus during a satisfactory time as required.

  16. Neurological and behavioral abnormalities, ventricular dilatation, altered cellular functions, inflammation, and neuronal injury in brains of mice due to common, persistent, parasitic infection

    Directory of Open Access Journals (Sweden)

    Hwang Jong-Hee

    2008-10-01

    Full Text Available Abstract Background Worldwide, approximately two billion people are chronically infected with Toxoplasma gondii with largely unknown consequences. Methods To better understand long-term effects and pathogenesis of this common, persistent brain infection, mice were infected at a time in human years equivalent to early to mid adulthood and studied 5–12 months later. Appearance, behavior, neurologic function and brain MRIs were studied. Additional analyses of pathogenesis included: correlation of brain weight and neurologic findings; histopathology focusing on brain regions; full genome microarrays; immunohistochemistry characterizing inflammatory cells; determination of presence of tachyzoites and bradyzoites; electron microscopy; and study of markers of inflammation in serum. Histopathology in genetically resistant mice and cytokine and NRAMP knockout mice, effects of inoculation of isolated parasites, and treatment with sulfadiazine or αPD1 ligand were studied. Results Twelve months after infection, a time equivalent to middle to early elderly ages, mice had behavioral and neurological deficits, and brain MRIs showed mild to moderate ventricular dilatation. Lower brain weight correlated with greater magnitude of neurologic abnormalities and inflammation. Full genome microarrays of brains reflected inflammation causing neuronal damage (Gfap, effects on host cell protein processing (ubiquitin ligase, synapse remodeling (Complement 1q, and also increased expression of PD-1L (a ligand that allows persistent LCMV brain infection and CD 36 (a fatty acid translocase and oxidized LDL receptor that mediates innate immune response to beta amyloid which is associated with pro-inflammation in Alzheimer's disease. Immunostaining detected no inflammation around intra-neuronal cysts, practically no free tachyzoites, and only rare bradyzoites. Nonetheless, there were perivascular, leptomeningeal inflammatory cells, particularly contiguous to the aqueduct of

  17. Body mass index and brain white matter structure in young adults at risk for psychosis - The Oulu Brain and Mind Study.

    Science.gov (United States)

    Koivukangas, Jenni; Björnholm, Lassi; Tervonen, Osmo; Miettunen, Jouko; Nordström, Tanja; Kiviniemi, Vesa; Mäki, Pirjo; Mukkala, Sari; Moilanen, Irma; Barnett, Jennifer H; Jones, Peter B; Nikkinen, Juha; Veijola, Juha

    2016-08-30

    Antipsychotic medications and psychotic illness related factors may affect both weight and brain structure in people with psychosis. Genetically high-risk individuals offer an opportunity to study the relationship between body mass index (BMI) and brain structure free from these potential confounds. We examined the effect of BMI on white matter (WM) microstructure in subjects with familial risk for psychosis (FR). We used diffusion tensor imaging and tract-based spatial statistics to explore the effect of BMI on whole brain FA in 42 (13 males) participants with FR and 46 (16 males) control participants aged 20-25 years drawn from general population-based Northern Finland Birth Cohort 1986. We also measured axial, radial and mean diffusivities. Most of the participants were normal weight rather than obese. In the FR group, decrease in fractional anisotropy and increase in radial diffusivity were associated with an increase in BMI in several brain areas. In controls the opposite pattern was seen in participants with higher BMI. There was a statistically significant interaction between group and BMI on FA and radial and mean diffusivities. Our results suggest that the effect of BMI on WM differs between individuals with FR for psychosis and controls. PMID:27474847

  18. A Structural Parametrization of the Brain Using Hidden Markov Models-Based Paths in Alzheimer's Disease.

    Science.gov (United States)

    Martinez-Murcia, Francisco J; Górriz, Juan M; Ramírez, Javier; Ortiz, Andres

    2016-11-01

    The usage of biomedical imaging in the diagnosis of dementia is increasingly widespread. A number of works explore the possibilities of computational techniques and algorithms in what is called computed aided diagnosis. Our work presents an automatic parametrization of the brain structure by means of a path generation algorithm based on hidden Markov models (HMMs). The path is traced using information of intensity and spatial orientation in each node, adapting to the structure of the brain. Each path is itself a useful way to characterize the distribution of the tissue inside the magnetic resonance imaging (MRI) image by, for example, extracting the intensity levels at each node or generating statistical information of the tissue distribution. Additionally, a further processing consisting of a modification of the grey level co-occurrence matrix (GLCM) can be used to characterize the textural changes that occur throughout the path, yielding more meaningful values that could be associated to Alzheimer's disease (AD), as well as providing a significant feature reduction. This methodology achieves moderate performance, up to 80.3% of accuracy using a single path in differential diagnosis involving Alzheimer-affected subjects versus controls belonging to the Alzheimer's disease neuroimaging initiative (ADNI). PMID:27354189

  19. Individual differences in cognitive performance and brain structure in typically developing children

    Directory of Open Access Journals (Sweden)

    Susumu Yokota

    2015-08-01

    Full Text Available Individual differences in cognitive patterning is informative in understanding one's cognitive strengths and weaknesses. However, little is known about the difference in brain structures relating to individual differences in cognitive patterning. In this study, we classified typically developing children (n = 277; age range, 5–16 years into subtypes with k-means cluster analysis along with factor index scores using the Wechsler Intelligence Scale for Children (Third Edition. We then applied voxel-based morphometry to investigate whether significant gray-matter-volume differences existed among subtypes of cognitive patterns. Depending on the level of performance and cognitive patterning, we obtained six subtypes. One subtype that generally scored below average showed larger volume in the right middle temporal gyrus than the other five. On the other hand, two subtypes that achieved average levels of performance showed reverse-patterned factor index scores (one scored higher in Verbal Comprehension and Freedom from Distractibility, and the other scored lower in these two factor index scores and had smaller volume in the right middle temporal gyrus than the other subtypes. From these results, we concluded that cognitive discrepancy was also obvious in typically developing children and that differences in cognitive patterning are represented in brain structure.

  20. Positive parenting predicts the development of adolescent brain structure: A longitudinal study

    Directory of Open Access Journals (Sweden)

    Sarah Whittle

    2014-04-01

    Full Text Available Little work has been conducted that examines the effects of positive environmental experiences on brain development to date. The aim of this study was to prospectively investigate the effects of positive (warm and supportive maternal behavior on structural brain development during adolescence, using longitudinal structural MRI. Participants were 188 (92 female adolescents, who were part of a longitudinal adolescent development study that involved mother–adolescent interactions and MRI scans at approximately 12 years old, and follow-up MRI scans approximately 4 years later. FreeSurfer software was used to estimate the volume of limbic-striatal regions (amygdala, hippocampus, caudate, putamen, pallidum, and nucleus accumbens and the thickness of prefrontal regions (anterior cingulate and orbitofrontal cortices across both time points. Higher frequency of positive maternal behavior during the interactions predicted attenuated volumetric growth in the right amygdala, and accelerated cortical thinning in the right anterior cingulate (males only and left and right orbitofrontal cortices, between baseline and follow up. These results have implications for understanding the biological mediators of risk and protective factors for mental disorders that have onset during adolescence.

  1. Blood-brain barrier permeability mechanisms in view of quantitative structure-activity relationships (QSAR).

    Science.gov (United States)

    Bujak, Renata; Struck-Lewicka, Wiktoria; Kaliszan, Michał; Kaliszan, Roman; Markuszewski, Michał J

    2015-04-10

    The goal of the present paper was to develop a quantitative structure-activity relationship (QSAR) method using a simple statistical approach, such as multiple linear regression (MLR) for predicting the blood-brain barrier (BBB) permeability of chemical compounds. The "best" MLR models, comprised logP and either molecular mass (M) or isolated atomic energy (E(isol)), tested on a structurally diverse set of 66 compounds, is characterized the by correlation coefficients (R) around 0.8. The obtained models were validated using leave-one-out (LOO) cross-validation technique and the correlation coefficient of leave-one-out- R(LOO)(2) (Q(2)) was at least 0.6. Analysis of a case from legal medicine demonstrated informative value of our QSAR model. To best authors' knowledge the present study is a first application of the developed QSAR models of BBB permeability to case from the legal medicine. Our data indicate that molecular energy-related descriptors, in combination with the well-known descriptors of lipophilicity may have a supportive value in predicting blood-brain distribution, which is of utmost importance in drug development and toxicological studies.

  2. Structural and functional correlates of visual field asymmetry in the human brain by diffusion kurtosis MRI and functional MRI.

    Science.gov (United States)

    O'Connell, Caitlin; Ho, Leon C; Murphy, Matthew C; Conner, Ian P; Wollstein, Gadi; Cham, Rakie; Chan, Kevin C

    2016-11-01

    Human visual performance has been observed to show superiority in localized regions of the visual field across many classes of stimuli. However, the underlying neural mechanisms remain unclear. This study aims to determine whether the visual information processing in the human brain is dependent on the location of stimuli in the visual field and the corresponding neuroarchitecture using blood-oxygenation-level-dependent functional MRI (fMRI) and diffusion kurtosis MRI, respectively, in 15 healthy individuals at 3 T. In fMRI, visual stimulation to the lower hemifield showed stronger brain responses and larger brain activation volumes than the upper hemifield, indicative of the differential sensitivity of the human brain across the visual field. In diffusion kurtosis MRI, the brain regions mapping to the lower visual field showed higher mean kurtosis, but not fractional anisotropy or mean diffusivity compared with the upper visual field. These results suggested the different distributions of microstructural organization across visual field brain representations. There was also a strong positive relationship between diffusion kurtosis and fMRI responses in the lower field brain representations. In summary, this study suggested the structural and functional brain involvements in the asymmetry of visual field responses in humans, and is important to the neurophysiological and psychological understanding of human visual information processing.

  3. STRUCTURAL AND FUNCTIONAL HETEROGENEITY OF ASTROCYTES IN THE BRAIN: ROLE IN NEURODEGENERATION AND NEUROINFLAMMATION

    Directory of Open Access Journals (Sweden)

    A. V. Morgun

    2014-01-01

    Full Text Available The review covers the current concepts on structural and functional heterogeneity of brain astrocytes that serve for numerous (pathophysiological processes in the central nervous system. Astrocytes from various subpopulations demonstrate different sensitivity to the action of pathogenic factors, varied behaviors in reactive processes and within the local immune response. Key functions of astrocytes like neurogenesis, neuron-astroglia metabolic coupling, glial control of local blood flow greatly depend on the origin and characteristics of astroglial cells. Changes at the initial stages of neurodegeneration or in neurodevelopmental disorders are associated with significant alterations in astroglial structural and functional properties, thus suggesting new approaches to therapeutic strategies implementing astroglia-expressing molecules and targets for effective

  4. Brain structure in post-traumatic stress disorder A voxel-based morphometry analysis**

    Institute of Scientific and Technical Information of China (English)

    Liwen Tan; Li Zhang; Rongfeng Qi; Guangming Lu; Lingjiang Li; Jun Liu; Weihui Li

    2013-01-01

    This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, us-ing the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, fol owed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lobule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal lobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group (r = 0.477, P = 0.039). Our findings indicate that (1) chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, occip-ital lobe, and parietal lobe, (2) after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and (3) the superior parietal lobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities.

  5. Neuropsychological function-brain structure relationships and stage of illness: an investigation into chronic and first-episode schizophrenia.

    Science.gov (United States)

    Premkumar, Preethi; Kumari, Veena; Corr, Philip J J; Fannon, Dominic; Sharma, Tonmoy

    2008-04-15

    Neuropsychological function-brain structure relationships may differ as a function of illness stage because of progressive brain matter loss through the course of schizophrenia. In this study, we tested whether neuropsychological function-brain structure relationships differed as a function of illness stage. In addition, we tested whether these relationships differed between older and young healthy controls. Function-structure relationships were examined in 35 first-episode patients (31 with schizophrenia, 4 with schizoaffective disorder), 54 chronic schizophrenia patients, 21 older healthy controls and 20 young healthy controls. MRI volumes of frontal and temporal lobe structures, as well as the whole brain, were estimated using a region-of-interest approach. Hierarchical multiple regression analyses were performed between the MRI and neuropsychological measures. Stronger relationships of immediate memory-total prefrontal cortex (PFC) volume in chronic than first-episode patients, and in older than young controls were observed. The abstract reasoning (WCST perseverative errors)-total temporal lobe volume relationship was stronger in older than young controls. These function-structure relationships appeared unexplained by whole brain volume or age in chronic patients. A similar dissociation between young and older subjects of both healthy and patient groups suggests that a 'bigger-is-better' relationship style is present in older individuals regardless of a diagnosis of schizophrenia. PMID:18226505

  6. MRI findings of brain damage due to neonatal hypoglycemia%新生儿低血糖脑损伤的MRI表现

    Institute of Scientific and Technical Information of China (English)

    王璐; 范国光; 冀旭; 孙宝海; 郭启勇

    2009-01-01

    that posterior parieto-occipital regions are most frequently injured in neonatal period due to severe hypoglycemia.DWI is a useful technique in the early detection and evaluation of hypoglycemic brain injury of neonates.%目的 初步探讨新生儿低血糖脑损伤的MRI表现特征及扩散加权成像(DWI)存早期发现低血糖脑损伤中的应用价值.方法 回顾性分析12例低血糖新生儿(其中10例诊断为新生儿低血糖脑病)MRI资料,12例患儿于出生后3至10 d内进行了头部MR扫描,包括常规T1 WI、T2、WI 和DWI扫描.其中4例在第一次检杏后7至10 d后再次行MR扫描.结果 12例首次DWI检查中11例出现异常高信号,受累脑区包括双侧枕叶皮层2例、右侧枕叶皮层1例、左侧枕叶皮层及皮层下1例,双侧枕叶皮层及皮层下2例、双侧顶枕叶皮层2例、舣侧顶枕叶皮层及皮层下2例、胼胝体压部4例、双侧放射冠2例、左侧尾状核及苍白球1例、舣侧背侧丘脑1例、双侧内囊后肢1例.12例首次常规T1 WI、T2 WI中,4例T1 WI呈现异常信号,表现为受累部位皮层T1信号减低3例、受累的双枕叶皮层稍短T1信号1例;5例T2 WI见异常信号,均表现为受累部位皮层及皮层下T2信号稍增高且灰白质分界不清.4例复查中,受累枕叶局部白质软化4例,残存枕叶皮层见条状稍高T1信号2例,双侧大脑半球白质呈弥漫性脱髓鞘改变1例,胼胝体压部T2高信号消失1例,胼胝体压部仍见稍高T2信号1例.结论 在新生儿期,可能和低血糖相关的腑拟伤多发生在双侧顶、枕叶后部脑组织.早期的DWI扫描有助于低血糖脑损伤的早期发现和评估.

  7. Seismic response due to travelling shear wave including soil-structure interaction with base-mat uplift

    International Nuclear Information System (INIS)

    The seismic response due to a travelling shear wave is investigated. The resulting input consists of a translational- and a torsional-acceleration time history. The combined result of the translational and torsional elastic response (the latter arises even in an axisymmetric structure) will not, in general, be larger than that encountered in the case of a spatially uniform earthquake. If the footing slips or becomes partially separated from the soil, a nonlinear dynamic analysis is performed. Substantial motions in all three directions will take place. A nuclear-reactor building is used for illustration. The peak structural responses and the floor - response spectra are found to be highly nonlinear for high acceleration input values

  8. Changes in plant cell-wall structure of corn stover due to hot compressed water pretreatment and enhanced enzymatic hydrolysis.

    Science.gov (United States)

    Zhou, Wei; Yang, Maohua; Wang, Caixia; Liu, Jianfei; Xing, Jianmin

    2014-08-01

    Corn stover is a potential feedstock for biofuel production. This work investigated physical and chemical changes in plant cell-wall structure of corn stover due to hot compressed water (HCW) pretreatment at 170-190 °C in a tube reactor. Chemical composition analysis showed the soluble hemicellulose content increased with pretreatment temperature, whereas the hemicellulose content decreased from 29 to 7 % in pretreated solids. Scanning electron microscopy revealed the parenchyma-type second cell-wall structure of the plant was almost completely removed at 185 °C, and the sclerenchyma-type second cell wall was greatly damaged upon addition of 5 mmol/L ammonium sulfate during HCW pretreatment. These changes favored accessibility for enzymatic action. Enzyme saccharification of solids by optimized pretreatment with HCW at 185 °C resulted in an enzymatic hydrolysis yield of 87 %, an enhancement of 77 % compared to the yield from untreated corn stover.

  9. Variation of local atomic structure due to devitrification of Ni-Zr alloy thin films probed by EXAFS measurements

    Science.gov (United States)

    Bhattacharya, Debarati; Tiwari, Nidhi; Bhattacharyya, Dibyendu; Jha, S. N.; Basu, S.

    2016-05-01

    Thin film metallic glasses (TFMGs) exhibit properties superior to their bulk counterparts allowing them to be potentially useful in many practical applications. Apart from their technological interest, when converted to crystallized state (devitrification) TFMGs can also act as precursors for partially crystallized or fully crystallized forms. Such devitrified forms are attractive due to their novel structural and magnetic properties. The amorphous-to-crystalline transformation of co-sputtered Ni-Zr alloy thin films through annealing was studied using EXAFS (Extended X-ray Absorption Fine Structure) measurements. Investigation through an atomic probe gives a better insight into the local environment of the atomic species, rendering a deeper understanding of thermal evolution of such materials.

  10. Selective vulnerability of Rich Club brain regions is an organizational principle of structural connectivity loss in Huntington's disease.

    Science.gov (United States)

    McColgan, Peter; Seunarine, Kiran K; Razi, Adeel; Cole, James H; Gregory, Sarah; Durr, Alexandra; Roos, Raymund A C; Stout, Julie C; Landwehrmeyer, Bernhard; Scahill, Rachael I; Clark, Chris A; Rees, Geraint; Tabrizi, Sarah J

    2015-11-01

    Huntington's disease can be predicted many years before symptom onset, and thus makes an ideal model for studying the earliest mechanisms of neurodegeneration. Diffuse patterns of structural connectivity loss occur in the basal ganglia and cortex early in the disease. However, the organizational principles that underlie these changes are unclear. By understanding such principles we can gain insight into the link between the cellular pathology caused by mutant huntingtin and its downstream effect at the macroscopic level. The 'rich club' is a pattern of organization established in healthy human brains, where specific hub 'rich club' brain regions are more highly connected to each other than other brain regions. We hypothesized that selective loss of rich club connectivity might represent an organizing principle underlying the distributed pattern of structural connectivity loss seen in Huntington's disease. To test this hypothesis we performed diffusion tractography and graph theoretical analysis in a pseudo-longitudinal study of 50 premanifest and 38 manifest Huntington's disease participants compared with 47 healthy controls. Consistent with our hypothesis we found that structural connectivity loss selectively affected rich club brain regions in premanifest and manifest Huntington's disease participants compared with controls. We found progressive network changes across controls, premanifest Huntington's disease and manifest Huntington's disease characterized by increased network segregation in the premanifest stage and loss of network integration in manifest disease. These regional and whole brain network differences were highly correlated with cognitive and motor deficits suggesting they have pathophysiological relevance. We also observed greater reductions in the connectivity of brain regions that have higher network traffic and lower clustering of neighbouring regions. This provides a potential mechanism that results in a characteristic pattern of structural

  11. Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia.

    Directory of Open Access Journals (Sweden)

    Carolyn D Langen

    Full Text Available Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, "bi-modal comparison plots" show the distribution of uni- and bi-modal group differences and the relationship between structure and function. Differences between brain lobes are visualized using "worm plots". Group differences in connections are examined with an existing visualization, the "connectogram". These visualizations were evaluated in two proof-of-concept studies: (1 middle-aged versus elderly subjects; and (2 patients with schizophrenia versus controls. Each included two measures derived from diffusion weighted images and two from functional magnetic resonance images. The structural measures were minimum cost path between two anatomical regions according to the "Statistical Analysis of Minimum cost path based Structural Connectivity" method and the average fractional anisotropy along the fiber. The functional measures were Pearson's correlation and partial correlation of mean regional time series. The relationship between structure and function was similar in both studies. Uni-modal group differences varied greatly between connectivity types. Group differences were identified in both studies globally, within brain lobes and between regions. In the aging study, minimum cost path was highly effective in identifying group differences on all levels; fractional anisotropy and mean correlation showed smaller differences on the brain lobe and regional levels. In the schizophrenia study, minimum cost path and fractional anisotropy showed differences on the global level and within brain lobes; mean correlation showed small differences on the lobe level. Only

  12. Comparative analysis of MR sequences to detect structural brain lesions in tuberous sclerosis

    International Nuclear Information System (INIS)

    Tuberous sclerosis (TS) is a neurocutaneous genetically inherited disease with variable penetrance characterized by dysplasias and hamartomas affecting multiple organs. MR is the imaging method of choice to demonstrate structural brain lesions in TS. To compare MR sequences and determine which is most useful for the demonstration of each type of brain lesion in TS patients. We reviewed MR scans of 18 TS patients for the presence of cortical tubers, white matter lesions (radial bands), subependymal nodules, and subependymal giant cell astrocytoma (SGCA) on the following sequences: (1) T1-weighted spin-echo (T1 SE) images before and after gadolinium (Gd) injection; (2) nonenhanced T1 SE sequence with an additional magnetization transfer contrast medium pulse on resonance (T1 SE/MTC); and (3) fluid-attenuated inversion recovery (FLAIR) sequence. Cortical tubers were found in significantly (P<0.05) larger numbers and more conspicuously in FLAIR and T1 SE/MTC sequences. The T1 SE/MTC sequence was far superior to other methods in detecting white matter lesions (P<0.01). There was no significant difference between the T1 SE/MTC and T1 SE (before and after Gd injection) sequences in the detection of subependymal nodules; FLAIR sequence showed less sensitivity than the others in identifying the nodules. T1 SE sequences after Gd injection demonstrated better the limits of the SGCA. We demonstrated the importance of appropriate MRI sequences for diagnosis of the most frequent brain lesions in TS. Our study reinforces the fact that each sequence has a particular application according to the type of TS lesion. Gd injection might be useful in detecting SGCA; however, the parameters of size and location are also important for a presumptive diagnosis of these tumors. (orig.)

  13. Comparative analysis of MR sequences to detect structural brain lesions in tuberous sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Pinto Gama, Hugo Pereira; Campos Meirelles, Rogerio Goncalves de; Mendonca do Rego, Jose Iram [Santa Casa de Misericordia de Sao Paulo, Section of Radiology, Sao Paulo (Brazil); Rocha, Antonio Jose da; Silva, Carlos Jorge da [Santa Casa de Misericordia de Sao Paulo, Section of Radiology, Centro de Medicina Diagnostica Fleury, Sao Paulo (Brazil); Braga, Flavio Tulio [Federal University of Sao Paulo, Escola Paulista de Medicina, Section of Radiology, Centro de Medicina Diagnostica Fleury, Santa Casa de Misericordia de Sao Paulo, Department of Diagnostic Imaging, Sao Paulo (Brazil); Martins Maia, Antonio Carlos [Federal University of Sao Paulo, Escola Paulista de Medicina, Section of Radiology, Centro de Medicina Diagnostica Fleury, Department of Neurology, Sao Paulo (Brazil); Lederman, Henrique Manoel [Federal University of Sao Paulo, Escola Paulista de Medicina, Division of Diagnostic Imaging in Pediatrics, Department of Diagnostic Imaging, Sao Paulo (Brazil)

    2006-02-01

    Tuberous sclerosis (TS) is a neurocutaneous genetically inherited disease with variable penetrance characterized by dysplasias and hamartomas affecting multiple organs. MR is the imaging method of choice to demonstrate structural brain lesions in TS. To compare MR sequences and determine which is most useful for the demonstration of each type of brain lesion in TS patients. We reviewed MR scans of 18 TS patients for the presence of cortical tubers, white matter lesions (radial bands), subependymal nodules, and subependymal giant cell astrocytoma (SGCA) on the following sequences: (1) T1-weighted spin-echo (T1 SE) images before and after gadolinium (Gd) injection; (2) nonenhanced T1 SE sequence with an additional magnetization transfer contrast medium pulse on resonance (T1 SE/MTC); and (3) fluid-attenuated inversion recovery (FLAIR) sequence. Cortical tubers were found in significantly (P<0.05) larger numbers and more conspicuously in FLAIR and T1 SE/MTC sequences. The T1 SE/MTC sequence was far superior to other methods in detecting white matter lesions (P<0.01). There was no significant difference between the T1 SE/MTC and T1 SE (before and after Gd injection) sequences in the detection of subependymal nodules; FLAIR sequence showed less sensitivity than the others in identifying the nodules. T1 SE sequences after Gd injection demonstrated better the limits of the SGCA. We demonstrated the importance of appropriate MRI sequences for diagnosis of the most frequent brain lesions in TS. Our study reinforces the fact that each sequence has a particular application according to the type of TS lesion. Gd injection might be useful in detecting SGCA; however, the parameters of size and location are also important for a presumptive diagnosis of these tumors. (orig.)

  14. Brain Correlates of Self-Evaluation Deficits in Schizophrenia: A Combined Functional and Structural MRI Study.

    Directory of Open Access Journals (Sweden)

    Shuping Tan

    Full Text Available Self-evaluation plays an important role in adaptive functioning and is a process that is typically impaired in patients with schizophrenia. Underlying neural mechanisms for this dysfunction may be associated with manifested psychosis. However, the brain substrates underlying this deficit are not well known. The present study used brain blood oxygen level dependent (BOLD functional magnetic resonance imaging (fMRI and gray matter voxel-based morphometry to explore the functional and structural brain correlates of self-evaluation deficits in schizophrenia. Eighteen patients with schizophrenia and 17 healthy controls were recruited and asked to judge whether a set of personality-trait adjectives were appropriate for describing themselves, a familiar other, or whether the adjectives were of positive or negative valence. Patients had slower response times for negative trait attributions than controls did; responses to positive trait attributions were faster than those for negative traits among the patient group, while no differences were observed in the control group. Control subjects showed greater activation within the dorsal medial prefrontal cortex (dMPFC and the anterior cingulate cortex (ACC than the patient group during the self-evaluation > semantic positivity-evaluation contrast. Patients showed greater activation mainly within the posterior cingulate gyrus (PCC as compared to controls for the other-evaluation > semantic positivity-evaluation contrast. Furthermore, gray matter volume was reduced in the MPFC, temporal lobe, cuneus, and the dorsal lateral prefrontal cortex (DLPFC among the patient group when compared to controls. The present study adds to previous findings regarding self- and other-referential processing in schizophrenia, providing support for neurobiological models of self-reflection impairment.

  15. Enhanced Proton Beam Focusing due to Proximal Target Structures on the 1.25 kJ OMEGA EP Laser

    Science.gov (United States)

    McGuffey, Chris; Kim, J.; Qiao, B.; Beg, F. N.; Wei, M. S.; Fitzsimmons, P.; Evans, M.; Stephens, R. B.; Fuchs, J.; Chen, S. N.; Nilson, P. M.; Canning, D.; Mastrosimone, D.; Foord, M. E.; McLean, H. S.

    2013-10-01

    Understanding how to generate and control laser-driven proton beams has shown significant progress in the last 15 years. However, to exploit promising applications, practical aspects must be addressed, such as the effect of structures holding the target and dynamics when the beam enters any sample. Using the 1.25 kJ, 10 ps OMEGA EP BL laser and spherically curved C targets we studied the spot size of a high-density proton beam directed at a Cu foil using three target mounting configurations: 1 on a stalk, 2 with an open-sided wedge structure on the back, and 3 with a conical structure. The brightness of Cu Kα fluorescence from the center of the foil was weakest from the stalk-mounted target, 5x brighter with the wedge, and 8x brighter with the cone, indicating enhanced focusing due to the structures. Plasma features and fields from the interaction were temporally and spatially resolved using proton radiography from a separate broad-spectrum proton beam (0-40 MeV) driven by OMEGA EP SL. We also discuss a follow-on experiment that will study transport of the proton beam through various materials. This work was supported by the DOE/NNSA NLUF program, Grant DE-NA0002034.

  16. Statistical machine learning to identify traumatic brain injury (TBI) from structural disconnections of white matter networks.

    Science.gov (United States)

    Mitra, Jhimli; Shen, Kai-kai; Ghose, Soumya; Bourgeat, Pierrick; Fripp, Jurgen; Salvado, Olivier; Pannek, Kerstin; Taylor, D Jamie; Mathias, Jane L; Rose, Stephen

    2016-04-01

    Identifying diffuse axonal injury (DAI) in patients with traumatic brain injury (TBI) presenting with normal appearing radiological MRI presents a significant challenge. Neuroimaging methods such as diffusion MRI and probabilistic tractography, which probe the connectivity of neural networks, show significant promise. We present a machine learning approach to classify TBI participants primarily with mild traumatic brain injury (mTBI) based on altered structural connectivity patterns derived through the network based statistical analysis of structural connectomes generated from TBI and age-matched control groups. In this approach, higher order diffusion models were used to map white matter connections between 116 cortical and subcortical regions. Tracts between these regions were generated using probabilistic tracking and mean fractional anisotropy (FA) measures along these connections were encoded in the connectivity matrices. Network-based statistical analysis of the connectivity matrices was performed to identify the network differences between a representative subset of the two groups. The affected network connections provided the feature vectors for principal component analysis and subsequent classification by random forest. The validity of the approach was tested using data acquired from a total of 179 TBI patients and 146 controls participants. The analysis revealed altered connectivity within a number of intra- and inter-hemispheric white matter pathways associated with DAI, in consensus with existing literature. A mean classification accuracy of 68.16%±1.81% and mean sensitivity of 80.0%±2.36% were achieved in correctly classifying the TBI patients evaluated on the subset of the participants that was not used for the statistical analysis, in a 10-fold cross-validation framework. These results highlight the potential for statistical machine learning approaches applied to structural connectomes to identify patients with diffusive axonal injury. PMID

  17. Obesity-related differences between women and men in brain structure and goal-directed behavior

    Directory of Open Access Journals (Sweden)

    Annette eHorstmann

    2011-06-01

    Full Text Available Gender differences in the regulation of body weight are well documented. Here, we assessed obesity-related influences of gender on brain structure as well as performance in the Iowa Gambling Task. This task requires evaluation of both immediate rewards and long-term outcomes and thus mirrors the trade-off between immediate reward from eating and the long-term effect of overeating on body weight. In women, but not in men, we show that the preference for salient immediate rewards in the face of negative long-term consequences is higher in obese than in lean subjects. In addition, we report structural differences in the left dorsal striatum (i.e. putamen and right dorsolateral prefrontal cortex for women only. Functionally, both regions are known to play complimentary roles in habitual and goal-directed control of behavior in motivational contexts. For women as well as men, gray matter volume correlates positively with measures of obesity in regions coding the value and saliency of food (i.e. nucleus accumbens, orbitofrontal cortex as well as in the hypothalamus (i.e. the brain's central homeostatic centre. These differences between lean and obese subjects in hedonic and homeostatic control systems may reflect a bias in eating behavior towards energy intake exceeding the actual homeostatic demand. Although we cannot infer from our results the etiology of the observed structural differences, our results resemble neural and behavioral differences well known from other forms of addiction, however, with marked differences between women and men. These findings are important for designing gender-appropriate treatments of obesity and possibly its recognition as a form of addiction.

  18. Reproducibility of the Structural Brain Connectome Derived from Diffusion Tensor Imaging.

    Directory of Open Access Journals (Sweden)

    Leonardo Bonilha

    Full Text Available Disruptions of brain anatomical connectivity are believed to play a central role in several neurological and psychiatric illnesses. The structural brain connectome is typically derived from diffusion tensor imaging (DTI, which may be influenced by methodological factors related to signal processing, MRI scanners and biophysical properties of neuroanatomical regions. In this study, we evaluated how these variables affect the reproducibility of the structural connectome.Twenty healthy adults underwent 3 MRI scanning sessions (twice in the same MRI scanner and a third time in a different scanner unit within a short period of time. The scanning sessions included similar T1 weighted and DTI sequences. Deterministic or probabilistic tractography was performed to assess link weight based on the number of fibers connecting gray matter regions of interest (ROI. Link weight and graph theory network measures were calculated and reproducibility was assessed through intra-class correlation coefficients, assuming each scanning session as a rater.Connectome reproducibility was higher with data from the same scanner. The probabilistic approach yielded larger reproducibility, while the individual variation in the number of tracked fibers from deterministic tractography was negatively associated with reproducibility. Links connecting larger and anatomically closer ROIs demonstrated higher reproducibility. In general, graph theory measures demonstrated high reproducibility across scanning sessions.Anatomical factors and tractography approaches can influence the reproducibility of the structural connectome and should be factored in the interpretation of future studies. Our results demonstrate that connectome mapping is a largely reproducible technique, particularly as it relates to the geometry of network architecture measured by graph theory methods.

  19. Structural and functional hallmarks of amyotrophic lateral sclerosis progression in motor- and memory-related brain regions

    Directory of Open Access Journals (Sweden)

    Christian Michael Stoppel

    2014-01-01

    Full Text Available Previous studies have shown that in amyotrophic lateral sclerosis (ALS multiple motor and extra-motor regions display structural and functional alterations. However, their temporal dynamics during disease-progression are unknown. To address this question we employed a longitudinal design assessing motor- and novelty-related brain activity in two fMRI sessions separated by a 3-month interval. In each session, patients and controls executed a Go/NoGo-task, in which additional presentation of novel stimuli served to elicit hippocampal activity. We observed a decline in the patients' movement-related activity during the 3-month interval. Importantly, in comparison to controls, the patients' motor activations were higher during the initial measurement. Thus, the relative decrease seems to reflect a breakdown of compensatory mechanisms due to progressive neural loss within the motor-system. In contrast, the patients' novelty-evoked hippocampal activity increased across 3 months, most likely reflecting the build-up of compensatory processes typically observed at the beginning of lesions. Consistent with a stage-dependent emergence of hippocampal and motor-system lesions, we observed a positive correlation between the ALSFRS-R or MRC-Megascores and the decline in motor activity, but a negative one with the hippocampal activation-increase. Finally, to determine whether the observed functional changes co-occur with structural alterations, we performed voxel-based volumetric analyses on magnetization transfer images in a separate patient cohort studied cross-sectionally at another scanning site. Therein, we observed a close overlap between the structural changes in this cohort, and the functional alterations in the other. Thus, our results provide important insights into the temporal dynamics of functional alterations during disease-progression, and provide support for an anatomical relationship between functional and structural cerebral changes in ALS.

  20. Simultaneous interpreters vs. professional multilingual controls: Group differences in cognitive control as well as brain structure and function.

    Science.gov (United States)

    Becker, Maxi; Schubert, Torsten; Strobach, Tilo; Gallinat, Jürgen; Kühn, Simone

    2016-07-01

    There is a vast amount of literature indicating that multiple language expertise leads to positive transfer effects onto other non-language cognitive domains possibly due to enhanced cognitive control. However, there is hardly any evidence about underlying mechanisms on how complex behavior like simultaneous interpreting benefits cognitive functioning in other non-language domains. Therefore, we investigated whether simultaneous interpreters (SIs) exhibit cognitive benefits in tasks measuring aspects of cognitive control compared to a professional multilingual control group. We furthermore investigated in how far potential cognitive benefits are related to brain structure (using voxel-based morphometry) and function (using regions-of-interest-based functional connectivity and graph-analytical measures on low-frequency BOLD signals in resting-state brain data). Concerning cognitive control, the results reveal that SIs exhibit less mixing costs in a task switching paradigm and a dual-task advantage compared to professional multilingual controls. In addition, SIs show more gray matter volume in the left frontal pole (BA 10) compared to controls. Graph theoretical analyses revealed that this region exhibits higher network values for global efficiency and degree and is functionally more strongly connected to the left inferior frontal gyrus and middle temporal gyrus in SIs compared to controls. Thus, the data provide evidence that SIs possess cognitive benefits in tasks measuring cognitive control. It is discussed in how far the central role of the left frontal pole and its stronger functional connectivity to the left inferior frontal gyrus represents a correlate of the neural mechanisms for the observed behavioral effects. PMID:27085505

  1. Functional Connectivity Abnormalities of Brain Regions with Structural Deficits in Young Adult Male Smokers

    Science.gov (United States)

    Bu, Limei; Yu, Dahua; Su, Shaoping; Ma, Yao; von Deneen, Karen M.; Luo, Lin; Zhai, Jinquan; Liu, Bo; Cheng, Jiadong; Guan, Yanyan; Li, Yangding; Bi, Yanzhi; Xue, Ting; Lu, Xiaoqi; Yuan, Kai

    2016-01-01

    Smoking is one of the most prevalent dependence disorders. Previous studies have detected structural and functional deficits in smokers. However, few studies focused on the changes of resting state functional connectivity (RSFC) of the brain regions with structural deficits in young adult smokers. Twenty-six young adult smokers and 26 well-matched healthy non-smokers participated in our study. Voxel-based morphometry (VBM) and RSFC were employed to investigate the structural and functional changes in young adult smokers. Compared with healthy non-smokers, young smokers showed increased gray matter (GM) volume in the left putamen and decreased GM volume in the left anterior cingulate cortex (ACC). Moreover, GM volume in the left ACC has a negative correlation trend with pack-years and GM volume in the left putamen was positively correlated with pack-years. The left ACC and putamen with abnormal volumes were chosen as the regions of interest (ROIs) for the RSFC analysis. We found that smokers showed increased RSFC between the left ACC and right amygdala and between the left putamen and right anterior insula. We revealed structural and functional deficits within the frontostriatal circuits in young smokers, which may shed new insights into the neural mechanisms of smoking.

  2. Structural brain changes related to bilingualism: does immersion make a difference?

    Science.gov (United States)

    Stein, Maria; Winkler, Carmen; Kaiser, Anelis; Dierks, Thomas

    2014-01-01

    Within the field of neuroscientific research on second language learning, considerable attention has been devoted to functional and recently also structural changes related to second language acquisition. The present literature review summarizes studies that investigated structural changes related to bilingualism. Furthermore, as recent evidence has suggested that native-like exposure to a second language (i.e., a naturalistic learning setting or immersion) considerably impacts second language learning, all findings are reflected with respect to the learning environment. Aggregating the existing evidence, we conclude that structural changes in left inferior frontal and inferior parietal regions have been observed in studies on cortical gray matter changes, while the anterior parts of the corpus callosum have been repeatedly found to reflect bilingualism in studies on white matter (WM) connectivity. Regarding the learning environment, no cortical alterations can be attributed specifically to naturalistic or classroom learning. With regard to WM changes, one might tentatively propose that changes in IFOF and SLF are possibly more prominently observed in studies investigating bilinguals with a naturalistic learning experience. However, future studies are needed to replicate and strengthen the existing evidence and to directly test the impact of naturalistic exposure on structural brain plasticity. PMID:25324816

  3. The effects of bilingualism on the white matter structure of the brain.

    Science.gov (United States)

    Pliatsikas, Christos; Moschopoulou, Elisavet; Saddy, James Douglas

    2015-02-01

    Recent studies suggest that learning and using a second language (L2) can affect brain structure, including the structure of white matter (WM) tracts. This observation comes from research looking at early and older bilingual individuals who have been using both their first and second languages on an everyday basis for many years. This study investigated whether young, highly immersed late bilinguals would also show structural effects in the WM that can be attributed to everyday L2 use, irrespective of critical periods or the length of L2 learning. Our Tract-Based Spatial Statistics analysis revealed higher fractional anisotropy values for bilinguals vs. monolinguals in several WM tracts that have been linked to language processing and in a pattern closely resembling the results reported for older and early bilinguals. We propose that learning and actively using an L2 after childhood can have rapid dynamic effects on WM structure, which in turn may assist in preserving WM integrity in older age. PMID:25583505

  4. Co-ordinated structural and functional covariance in the adolescent brain underlies face processing performance.

    Science.gov (United States)

    Shaw, Daniel Joel; Mareček, Radek; Grosbras, Marie-Helene; Leonard, Gabriel; Pike, G Bruce; Paus, Tomáš

    2016-04-01

    Our ability to process complex social cues presented by faces improves during adolescence. Using multivariate analyses of neuroimaging data collected longitudinally from a sample of 38 adolescents (17 males) when they were 10, 11.5, 13 and 15 years old, we tested the possibility that there exists parallel variations in the structural and functional development of neural systems supporting face processing. By combining measures of task-related functional connectivity and brain morphology, we reveal that both the structural covariance and functional connectivity among 'distal' nodes of the face-processing network engaged by ambiguous faces increase during this age range. Furthermore, we show that the trajectory of increasing functional connectivity between the distal nodes occurs in tandem with the development of their structural covariance. This demonstrates a tight coupling between functional and structural maturation within the face-processing network. Finally, we demonstrate that increased functional connectivity is associated with age-related improvements of face-processing performance, particularly in females. We suggest that our findings reflect greater integration among distal elements of the neural systems supporting the processing of facial expressions. This, in turn, might facilitate an enhanced extraction of social information from faces during a time when greater importance is placed on social interactions.

  5. The impact of television viewing on brain structures: cross-sectional and longitudinal analyses.

    Science.gov (United States)

    Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Asano, Kohei; Asano, Michiko; Sassa, Yuko; Yokota, Susumu; Kotozaki, Yuka; Nouchi, Rui; Kawashima, Ryuta

    2015-05-01

    Television (TV) viewing is known to affect children's verbal abilities and other physical, cognitive, and emotional development in psychological studies. However, the brain structural development associated with TV viewing has never been investigated. Here we examined cross-sectional correlations between the duration of TV viewing and regional gray/white matter volume (rGMV/rWMV) among 133 boys and 143 girls as well as correlations between the duration of TV viewing and longitudinal changes that occurred a few years later among 111 boys and 105 girls. After correcting for confounding factors, we found positive effects of TV viewing on rGMV of the frontopolar and medial prefrontal areas in cross-sectional and longitudinal analyses, positive effects of TV viewing on rGMV/rWMV of areas of the visual cortex in cross-sectional analyses, and positive effects of TV viewing on rGMV of the hypothalamus/septum and sensorimotor areas in longitudinal analyses. We also confirmed negative effects of TV viewing on verbal intelligence quotient (IQ) in cross-sectional and longitudinal analyses. These anatomical correlates may be linked to previously known effects of TV viewing on verbal competence, aggression, and physical activity. In particular, the present results showed effects of TV viewing on the frontopolar area of the brain, which has been associated with intellectual abilities.

  6. The impact of television viewing on brain structures: cross-sectional and longitudinal analyses.

    Science.gov (United States)

    Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Asano, Kohei; Asano, Michiko; Sassa, Yuko; Yokota, Susumu; Kotozaki, Yuka; Nouchi, Rui; Kawashima, Ryuta

    2015-05-01

    Television (TV) viewing is known to affect children's verbal abilities and other physical, cognitive, and emotional development in psychological studies. However, the brain structural development associated with TV viewing has never been investigated. Here we examined cross-sectional correlations between the duration of TV viewing and regional gray/white matter volume (rGMV/rWMV) among 133 boys and 143 girls as well as correlations between the duration of TV viewing and longitudinal changes that occurred a few years later among 111 boys and 105 girls. After correcting for confounding factors, we found positive effects of TV viewing on rGMV of the frontopolar and medial prefrontal areas in cross-sectional and longitudinal analyses, positive effects of TV viewing on rGMV/rWMV of areas of the visual cortex in cross-sectional analyses, and positive effects of TV viewing on rGMV of the hypothalamus/septum and sensorimotor areas in longitudinal analyses. We also confirmed negative effects of TV viewing on verbal intelligence quotient (IQ) in cross-sectional and longitudinal analyses. These anatomical correlates may be linked to previously known effects of TV viewing on verbal competence, aggression, and physical activity. In particular, the present results showed effects of TV viewing on the frontopolar area of the brain, which has been associated with intellectual abilities. PMID:24256892

  7. Glucocorticoid regulation of brain-derived neurotrophic factor: relevance to hippocampal structural and functional plasticity.

    Science.gov (United States)

    Suri, D; Vaidya, V A

    2013-06-01

    Glucocorticoids serve as key stress response hormones that facilitate stress coping. However, sustained glucocorticoid exposure is associated with adverse consequences on the brain, in particular within the hippocampus. Chronic glucocorticoid exposure evokes neuronal cell damage and dendritic atrophy, reduces hippocampal neurogenesis and impairs synaptic plasticity. Glucocorticoids also alter expression and signaling of the neurotrophin, brain-derived neurotrophic factor (BDNF). Since BDNF is known to promote neuroplasticity, enhance cell survival, increase hippocampal neurogenesis and cellular excitability, it has been hypothesized that specific adverse effects of glucocorticoids may be mediated by attenuating BDNF expression and signaling. The purpose of this review is to summarize the current state of literature examining the influence of glucocorticoids on BDNF, and to address whether specific effects of glucocorticoids arise through perturbation of BDNF signaling. We integrate evidence of glucocorticoid regulation of BDNF at multiple levels, spanning from the well-documented glucocorticoid-induced changes in BDNF mRNA to studies examining alterations in BDNF receptor-mediated signaling. Further, we delineate potential lines of future investigation to address hitherto unexplored aspects of the influence of glucocorticoids on BDNF. Finally, we discuss the current understanding of the contribution of BDNF to the modulation of structural and functional plasticity by glucocorticoids, in particular in the context of the hippocampus. Understanding the mechanistic crosstalk between glucocorticoids and BDNF holds promise for the identification of potential therapeutic targets for disorders associated with the dysfunction of stress hormone pathways.

  8. Structural brain abnormalities in the frontostriatal system and cerebellum in pedophilia.

    Science.gov (United States)

    Schiffer, Boris; Peschel, Thomas; Paul, Thomas; Gizewski, Elke; Forsting, Michael; Leygraf, Norbert; Schedlowski, Manfred; Krueger, Tillmann H C

    2007-11-01

    Even though previous neuropsychological studies and clinical case reports have suggested an association between pedophilia and frontocortical dysfunction, our knowledge about the neurobiological mechanisms underlying pedophilia is still fragmentary. Specifically, the brain morphology of such disorders has not yet been investigated using MR imaging techniques. Whole brain structural T1-weighted MR images from 18 pedophile patients (9 attracted to males, 9 attracted to females) and 24 healthy age-matched control subjects (12 hetero- and 12 homosexual) from a comparable socioeconomic stratum were processed by using optimized automated voxel-based morphometry within multiple linear regression analyses. Compared to the homosexual and heterosexual control subjects, pedophiles showed decreased gray matter volume in the ventral striatum (also extending into the nucl. accumbens), the orbitofrontal cortex and the cerebellum. These observations further indicate an association between frontostriatal morphometric abnormalities and pedophilia. In this respect these findings may support the hypothesis that there is a shared etiopathological mechanism in all obsessive-compulsive spectrum disorders. PMID:16876824

  9. Brain structure and cognitive correlates of body mass index in healthy older adults

    Science.gov (United States)

    Bolzenius, Jacob D.; Laidlaw, David H.; Cabeen, Ryan P.; Conturo, Thomas E.; McMichael, Amanda R.; Lane, Elizabeth M.; Heaps, Jodi M.; Salminen, Lauren E.; Baker, Laurie M.; Scott, Staci E.; Cooley, Sarah A.; Gunstad, John; Paul, Robert H.

    2014-01-01

    Obesity, commonly measured with body mass index (BMI), is associated with numerous deleterious health conditions including alterations in brain integrity related to advanced age. Prior research has suggested that white matter integrity observed using diffusion tensor imaging (DTI) is altered in relation to high BMI, but the integrity of specific white matter tracts remains poorly understood. Additionally, no studies have examined white matter tract integrity in conjunction with neuropsychological evaluation associated with BMI among older adults. The present study examined white matter tract integrity using DTI and cognitive performance associated with BMI in 62 healthy older adults (20 males, 42 females) aged 51 to 81. Results revealed that elevated BMI was associated with lower fractional anisotropy (FA) in the uncinate fasciculus, though there was no evidence of an age by BMI interaction relating to FA in this tract. No relationships were observed between BMI and other white matter tracts or cognition after controlling for demographic variables. Findings suggest that elevated BMI is associated with lower structural integrity in a brain region connecting frontal and temporal lobes and this alteration precedes cognitive dysfunction. Future studies should examine biological mechanisms that mediate the relationships between BMI and white matter tract integrity, as well as the evolution of these abnormalities utilizing longitudinal designs. PMID:25448431

  10. Structural bases for neurophysiological investigations of amygdaloid complex of the brain

    Science.gov (United States)

    Kalimullina, Liliya B.; Kalkamanov, Kh. A.; Akhmadeev, Azat V.; Zakharov, Vadim P.; Sharafullin, Ildus F.

    2015-11-01

    Amygdala (Am) as a part of limbic system of the brain defines such important functions as adaptive behavior of animals, formation of emotions and memory, regulation of endocrine and visceral functions. We worked out, with the help of mathematic modelling of the pattern recognition theory, principles for organization of neurophysiological and neuromorphological studies of Am nuclei, which take into account the existing heterogeneity of its formations and optimize, to a great extent, the protocol for carrying out of such investigations. The given scheme of studies of Am’s structural-functional organization at its highly-informative sections can be used as a guide for precise placement of electrodes’, cannulae’s and microsensors into particular Am nucleus in the brain with the registration not only the nucleus itself, but also its extensions. This information is also important for defining the number of slices covering specific Am nuclei which must be investigated to reveal the physiological role of a particular part of amygdaloid complex.

  11. BRAIN PLASTICITY: MUSICAL TRAINING INVOLVEMENT

    Directory of Open Access Journals (Sweden)

    Verónika Diaz Abrahan

    2012-12-01

    Full Text Available The main research about the effect of musical training in adult and childhood brain was revised in this work. The music realizes unique demands to our ner-vous system. This call the attention of several researchers causing, in the past years, an enhancement of the exploration about this topic; this increment was benefit for the emergence of new neuroimaging techniques, the music positioned as an investigation tool of human cognition and superior brain mechanisms. The musical perception and production are specific functions of the human brain that depend of a wide cortical-subcortical neural net distributed across both hemi-spheres and cerebellum. The main findings in this area indicated structural and functional differences in the adult and child brain due to musical training, and this is more relevant that innate properties of the subject. There is brain plasticity due to adaptive processes product of the environmental stimulation.

  12. Spatio-Temporal Structuring of Brain Activity - Description of Interictal EEG in Paediatric Frontal Lobe Epilepsy

    CERN Document Server

    Bunk, W; Kluger, G; Springer, S

    2009-01-01

    A method for the quantitative assessment of spatio-temporal structuring of brain activity is presented. This approach is employed in a longitudinal case study of a child with frontal lobe epilepsy (FLE) and tested against an age-matched control group. Several correlation measures that are sensitive to linear and/or non-linear relations in multichannel scalp EEG are combined with an hierarchical cluster algorithm. Beside a quantitative description of the overall degree of synchronization the spatial relations are investigated by means of the cluster characteristics. The chosen information measures not only demonstrate their suitability in the characterization of the ictal and interictal phases but they also follow the course of delayed recovery of the psychiatric symptomatology during successful medication. The results based on this single case study suggest testing this approach for quantitative control of therapy in an extended clinical trial.

  13. Brain Emotion Systems, Personality, Hopelessness, Self/Other Perception, and Gambling Cognition: A Structural Equation Model.

    Science.gov (United States)

    Iliceto, Paolo; D'Antuono, Laura; Bowden-Jones, Henrietta; Giovani, Eleni; Giacolini, Teodosio; Candilera, Gabriella; Sabatello, Ugo; Panksepp, Jaak

    2016-03-01

    The aim of this study was to explore the relations between gambling, brain emotion systems, personality, self/other perception, and hopelessness in an Italian community. Dimensions of gambling, positive and negative emotions, self/other perception, personality and hopelessness were assessed in a community sample of 235 adults aged 19-59 years. Two structural models were tested. We found a significant correlation between problem gambling and impulsivity, which in association with aggressivity and negative personality dimensions may help explain the psychopathology factor, i.e. a latent variable involving neurotic personality, hopelessness, high sensation seeking, low metacognitive responsiveness, and disorganized patterns of interpersonal relationships. These results contribute to develop a theoretical framework of gambling in relation with personality factors and provide a new approach for clinical intervention of problem gambling that relies on a solid multidimensional perspective. PMID:25894294

  14. Structured light 3D tracking system for measuring motions in PET brain imaging

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Jørgensen, Morten Rudkjær; Paulsen, Rasmus Reinhold;

    2010-01-01

    with a DLP projector and a CCD camera is set up on a model of the High Resolution Research Tomograph (HRRT). Methods to reconstruct 3D point clouds of simple surfaces based on phase-shifting interferometry (PSI) are demonstrated. The projector and camera are calibrated using a simple stereo vision procedure......Patient motion during scanning deteriorates image quality, especially for high resolution PET scanners. A new proposal for a 3D head tracking system for motion correction in high resolution PET brain imaging is set up and demonstrated. A prototype tracking system based on structured light...... where the projector is treated as a camera. Additionally, the surface reconstructions are corrected for the non-linear projector output prior to image capture. The results are convincing and a first step toward a fully automated tracking system for measuring head motions in PET imaging...

  15. Functional and Structural Correlates of Social Influence in the Human Brain

    DEFF Research Database (Denmark)

    Campbell-Meiklejohn, Daniel; Bach, Dominik; Kanai, Ryota;

    2012-01-01

    of choosing enjoyable music, had listened to each song. Subjects performed the task in Figure 1 in the scanner. During a trial, subjects indicated their preference, given a choice of a song they had submitted and an alternative song they had never heard. Subjects were then told which song reviewers preferred...... provided names of twenty pieces of music that they would like to own, but did not own yet. On test day, subjects rated each submitted song for desirability, from 1 (low) to 10 (high). Next, subjects were told that two music 'reviewers', of whom subjects had read descriptions and rated as capable...... brain GM) in the volumetric based morphology (VBM) contrast of GM in OFC. OFCGM found to correlate (FWE corrected, P >.05) with Binf, was used as a regressor in the group fMRI contrasts of (a) and (b) to investigate the relationship between structure and activity during conformity....

  16. Brain Emotion Systems, Personality, Hopelessness, Self/Other Perception, and Gambling Cognition: A Structural Equation Model.

    Science.gov (United States)

    Iliceto, Paolo; D'Antuono, Laura; Bowden-Jones, Henrietta; Giovani, Eleni; Giacolini, Teodosio; Candilera, Gabriella; Sabatello, Ugo; Panksepp, Jaak

    2016-03-01

    The aim of this study was to explore the relations between gambling, brain emotion systems, personality, self/other perception, and hopelessness in an Italian community. Dimensions of gambling, positive and negative emotions, self/other perception, personality and hopelessness were assessed in a community sample of 235 adults aged 19-59 years. Two structural models were tested. We found a significant correlation between problem gambling and impulsivity, which in association with aggressivity and negative personality dimensions may help explain the psychopathology factor, i.e. a latent variable involving neurotic personality, hopelessness, high sensation seeking, low metacognitive responsiveness, and disorganized patterns of interpersonal relationships. These results contribute to develop a theoretical framework of gambling in relation with personality factors and provide a new approach for clinical intervention of problem gambling that relies on a solid multidimensional perspective.

  17. Differing patterns of brain structural abnormalities between black and white patients with their first episode of psychosis.

    LENUS (Irish Health Repository)

    Morgan, K D

    2010-07-01

    African-Caribbean and black African people living in the UK are reported to have a higher incidence of diagnosed psychosis compared with white British people. It has been argued that this may be a consequence of misdiagnosis. If this is true they might be less likely to show the patterns of structural brain abnormalities reported in white British patients. The aim of this study therefore was to investigate whether there are differences in the prevalence of structural brain abnormalities in white and black first-episode psychosis patients.

  18. Stiffness in vortex-like structures due to chirality-domains within a coupled helical rare-earth superlattice.

    Science.gov (United States)

    Paul, Amitesh

    2016-01-01

    Vortex domain walls poses chirality or 'handedness' which can be exploited to act as memory units by changing their polarity with electric field or driving/manupulating the vortex itself by electric currents in multiferroics. Recently, domain walls formed by one dimensional array of vortex-like structures have been theoretically predicted to exist in disordered rare-earth helical magnets with topological defects. Here, in this report, we have used a combination of two rare-earth metals, e.g. superlattice that leads to long range magnetic order despite their competing anisotropies along the out-of-plane (Er) and in-plane (Tb) directions. Probing the vertically correlated magnetic structures by off-specular polarized neutron scattering we confirm the existence of such magnetic vortex-like domains associated with magnetic helical ordering within the Er layers. The vortex-like structures are predicted to have opposite chirality, side-by-side, and are fairly unaffected by the introduction of magnetic ordering between the interfacial Tb layers and also with the increase in magnetic field which is a direct consequence of screening of the vorticity in the system due to a helical background. Overall, the stability of these vortices over a wide range of temperatures, fields and interfacial coupling, opens up the opportunity for fundamental chiral spintronics in unconventional systems. PMID:26758314

  19. Stiffness in vortex—like structures due to chirality-domains within a coupled helical rare-earth superlattice

    Science.gov (United States)

    Paul, Amitesh

    2016-01-01

    Vortex domain walls poses chirality or ‘handedness’ which can be exploited to act as memory units by changing their polarity with electric field or driving/manupulating the vortex itself by electric currents in multiferroics. Recently, domain walls formed by one dimensional array of vortex—like structures have been theoretically predicted to exist in disordered rare-earth helical magnets with topological defects. Here, in this report, we have used a combination of two rare-earth metals, e.g. superlattice that leads to long range magnetic order despite their competing anisotropies along the out-of-plane (Er) and in-plane (Tb) directions. Probing the vertically correlated magnetic structures by off-specular polarized neutron scattering we confirm the existence of such magnetic vortex—like domains associated with magnetic helical ordering within the Er layers. The vortex—like structures are predicted to have opposite chirality, side—by—side, and are fairly unaffected by the introduction of magnetic ordering between the interfacial Tb layers and also with the increase in magnetic field which is a direct consequence of screening of the vorticity in the system due to a helical background. Overall, the stability of these vortices over a wide range of temperatures, fields and interfacial coupling, opens up the opportunity for fundamental chiral spintronics in unconventional systems.

  20. Nonmonotonous electron mobility due to structurally induced resonant coupling of subband states in an asymmetric double quantum well

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, R. K.; Das, S.; Panda, A. K.; Sahu, T., E-mail: tsahu-bu@rediffmail.com [Department of Electronics and Communication Engineering, National Institute of Science and Technology, Palur Hills, Berhampur-761 008, Odisha (India)

    2015-11-15

    We show that sharp nonmonotic variation of low temperature electron mobility μ can be achieved in GaAs/Al{sub x}Ga{sub 1-x}As barrier delta-doped double quantum well structure due to quantum mechanical transfer of subband electron wave functions within the wells. We vary the potential profile of the coupled structure as a function of the doping concentration in order to bring the subbands into resonance such that the subband energy levels anticross and the eigen states of the coupled structure equally share both the wells thereby giving rise to a dip in mobility. When the wells are of equal widths, the dip in mobility occurs under symmetric doping of the side barriers. In case of unequal well widths, the resonance can be obtained by suitable asymmetric variation of the doping concentrations. The dip in mobility becomes sharp and also the wavy nature of mobility takes a rectangular shape by increasing the barrier width. We show that the dip in mobility at resonance is governed by the interface roughness scattering through step like changes in the subband mobilities. It is also gratifying to show that the drop in mobility at the onset of occupation of second subband is substantially supressed through the quantum mechanical transfer of subband wave functions between the wells. Our results can be utilized for performance enhancement of coupled quantum well devices.

  1. Probabilistic anatomical labeling of brain structures using statistical probabilistic anatomical maps

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Lee, Dong Soo; Lee, Byung Il; Lee, Jae Sung; Shin, Hee Won; Chung, June Key; Lee, Myung Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2002-12-01

    The use of statistical parametric mapping (SPM) program has increased for the analysis of brain PET and SPECT images. Montreal neurological institute (MNI) coordinate is used in SPM program as a standard anatomical framework. While the most researchers look up Talairach atlas to report the localization of the activations detected in SPM program, there is significant disparity between MNI templates and Talairach atlas. That disparity between Talairach and MNI coordinates makes the interpretation of SPM result time consuming, subjective and inaccurate. The purpose of this study was to develop a program to provide objective anatomical information of each x-y-z position in ICBM coordinate. Program was designed to provide the anatomical information for the given x-y-z position in MNI coordinate based on the statistical probabilistic anatomical map (SPAM) images of ICBM. When x-y-z position was given to the program, names of the anatomical structures with non-zero probability and the probabilities that the given position belongs to the structures were tabulated. The program was coded using IDL and JAVA language for the easy transplantation to any operating system or platform. Utility of this program was shown by comparing the results of this program to those of SPM program. Preliminary validation study was performed by applying this program to the analysis of PET brain activation study of human memory in which the anatomical information on the activated areas are previously known. Real time retrieval of probabilistic information with 1 mm spatial resolution was archived using the programs. Validation study showed the relevance of this program: probability that the activated area for memory belonged to hippocampal formation was more than 80%. These programs will be useful for the result interpretation of the image analysis performed on MNI coordinate, as done in SPM program.

  2. Magnetic resonance imaging structural alterations in brain of alcohol abusers and its association with impulsivity.

    Science.gov (United States)

    Asensio, Samuel; Morales, Julia L; Senabre, Isabel; Romero, Maria J; Beltran, Miguel A; Flores-Bellver, Miguel; Barcia, Jorge M; Romero, Francisco J

    2016-07-01

    Despite the suggestion that impulsivity plays a central role in the transfer from a recreational drug use to a substance use disorder, very few studies focused on neurobiological markers for addiction. This study aimed to identify volumetric alterations in a sample of patients with mild alcohol use disorder with a short history of alcohol use, compared with a control group, and also focused on its association with impulsivity levels. Most magnetic resonance imaging studies have focused on severe alcohol use disorder, formerly called alcohol-dependent patients, showing alcohol-related structural alterations and their association with alcohol use history variables but not with personality parameters like impulsivity. Our hypothesis is that our group of alcohol users may already display structural alterations especially in brain regions related to inhibitory control like medial-prefrontal regions, and that those structural alterations could be more associated to personality traits like impulsivity than to drug use variables. Our results clearly demonstrate that our population showed lower regional grey and white matter volumes in the medial-prefrontal and orbitofrontal cortices, as well as higher regional white matter volume in the ventral striatum and the internal capsule. Volumetric alterations were associated to the Barratt's impulsivity score: the more impulsive the subjects, the lower the medial-prefrontal cortex grey matter volume. PMID:25988724

  3. Differential compromise of prospective and retrospective metamemory monitoring and their dissociable structural brain correlates.

    Science.gov (United States)

    Le Berre, Anne-Pascale; Müller-Oehring, Eva M; Kwon, Dongjin; Serventi, Matthew R; Pfefferbaum, Adolf; Sullivan, Edith V

    2016-08-01

    Metamemory refers to personal knowledge about one's own memory ability that invokes cognitive processes relevant to monitoring and controlling memory. An impaired monitoring system can potentially result in unawareness of symptoms as can occur in addiction denial. Monitoring processes can be assessed with prospective measures such as Feeling-Of-Knowing (FOK) judgments on prediction of future recognition performance, or retrospective confidence judgments (RCJ) made on previous memory performance. Alcoholic patients with amnesia showed poor FOK but intact RCJ. The neuropsychological continuum from mild to moderate deficits in nonamnesic to amnesic alcoholism raised the possibility that alcoholics uncomplicated by clinically-detectable amnesia may suffer anosognosia for their mild memory deficits. Herein 24 abstinent alcoholics and 26 age-matched controls completed an episodic memory paradigm including prospective FOK and retrospective RCJ monitoring measures and underwent 3T structural magnetic resonance imaging. Alcoholics were less accurate than controls in recognition and in assessing their future recognition performance, which was marked by overestimation, but were as accurate as controls on confidence ratings of actual recognition performance. Examination of brain structure-function relations revealed a double dissociation where FOK accuracy was selectively related to insular volume, and retrospective confidence accuracy was selectively related to frontolimbic structural volumes. Impaired FOK with intact RCJ was consistent with mild anosognosia and suggested evidence for neuropsychological and neural mechanisms of unawareness in addiction. PMID:27244277

  4. Prediction of individual differences in risky behaviour in young adults via variations in local brain structure

    Directory of Open Access Journals (Sweden)

    Zahra eNasiriavanaki

    2015-10-01

    Full Text Available In recent years the problem of how inter-individual differences play a role in risk-taking behaviour has become a much debated issue. We investigated this problem based on the well-known balloon analogue risk task (BART in which participants inflate a virtual balloon opting for a higher score in the face of a riskier chance of the balloon explosion. In this study, based on a structural Voxel Based Morphometry (VBM technique we demonstrate a significant positive correlation between BART score and size of the grey matter volume in the anterior insula in riskier subjects. Although the anterior insula is among the candidate brain areas that were involved in the risk taking behaviour in fMRI studies, here based on our structural data it is the sole area with a significant structural variation among different subjects. Also a seemingly conflicting finding is discussed where the anterior insula is shown to be more active in risk aversive subjects.

  5. Evidence for training-induced plasticity in multisensory brain structures: an MEG study.

    Science.gov (United States)

    Paraskevopoulos, Evangelos; Kuchenbuch, Anja; Herholz, Sibylle C; Pantev, Christo

    2012-01-01

    Multisensory learning and resulting neural brain plasticity have recently become a topic of renewed interest in human cognitive neuroscience. Music notation reading is an ideal stimulus to study multisensory learning, as it allows studying the integration of visual, auditory and sensorimotor information processing. The present study aimed at answering whether multisensory learning alters uni-sensory structures, interconnections of uni-sensory structures or specific multisensory areas. In a short-term piano training procedure musically naive subjects were trained to play tone sequences from visually presented patterns in a music notation-like system [Auditory-Visual-Somatosensory group (AVS)], while another group received audio-visual training only that involved viewing the patterns and attentively listening to the recordings of the AVS training sessions [Auditory-Visual group (AV)]. Training-related changes in cortical networks were assessed by pre- and post-training magnetoencephalographic (MEG) recordings of an auditory, a visual and an integrated audio-visual mismatch negativity (MMN). The two groups (AVS and AV) were differently affected by the training. The results suggest that multisensory training alters the function of multisensory structures, and not the uni-sensory ones along with their interconnections, and thus provide an answer to an important question presented by cognitive models of multisensory training. PMID:22570723

  6. Evidence for training-induced plasticity in multisensory brain structures: an MEG study.

    Directory of Open Access Journals (Sweden)

    Evangelos Paraskevopoulos

    Full Text Available Multisensory learning and resulting neural brain plasticity have recently become a topic of renewed interest in human cognitive neuroscience. Music notation reading is an ideal stimulus to study multisensory learning, as it allows studying the integration of visual, auditory and sensorimotor information processing. The present study aimed at answering whether multisensory learning alters uni-sensory structures, interconnections of uni-sensory structures or specific multisensory areas. In a short-term piano training procedure musically naive subjects were trained to play tone sequences from visually presented patterns in a music notation-like system [Auditory-Visual-Somatosensory group (AVS], while another group received audio-visual training only that involved viewing the patterns and attentively listening to the recordings of the AVS training sessions [Auditory-Visual group (AV]. Training-related changes in cortical networks were assessed by pre- and post-training magnetoencephalographic (MEG recordings of an auditory, a visual and an integrated audio-visual mismatch negativity (MMN. The two groups (AVS and AV were differently affected by the training. The results suggest that multisensory training alters the function of multisensory structures, and not the uni-sensory ones along with their interconnections, and thus provide an answer to an important question presented by cognitive models of multisensory training.

  7. Novel fingerprinting method characterises the necessary and sufficient structural connectivity from deep brain stimulation electrodes for a successful outcome

    Science.gov (United States)

    Fernandes, Henrique M.; Van Hartevelt, Tim J.; Boccard, Sandra G. J.; Owen, Sarah L. F.; Cabral, Joana; Deco, Gustavo; Green, Alex L.; Fitzgerald, James J.; Aziz, Tipu Z.; Kringelbach, Morten L.

    2015-01-01

    Deep brain stimulation (DBS) is a remarkably effective clinical tool, used primarily for movement disorders. DBS relies on precise targeting of specific brain regions to rebalance the oscillatory behaviour of whole-brain neural networks. Traditionally, DBS targeting has been based upon animal models (such as MPTP for Parkinson’s disease) but has also been the result of serendipity during human lesional neurosurgery. There are, however, no good animal models of psychiatric disorders such as depression and schizophrenia, and progress in this area has been slow. In this paper, we use advanced tractography combined with whole-brain anatomical parcellation to provide a rational foundation for identifying the connectivity ‘fingerprint’ of existing, successful DBS targets. This knowledge can then be used pre-surgically and even potentially for the discovery of novel targets. First, using data from our recent case series of cingulate DBS for patients with treatment-resistant chronic pain, we demonstrate how to identify the structural ‘fingerprints’ of existing successful and unsuccessful DBS targets in terms of their connectivity to other brain regions, as defined by the whole-brain anatomical parcellation. Second, we use a number of different strategies to identify the successful fingerprints of structural connectivity across four patients with successful outcomes compared with two patients with unsuccessful outcomes. This fingerprinting method can potentially be used pre-surgically to account for a patient’s individual connectivity and identify the best DBS target. Ultimately, our novel fingerprinting method could be combined with advanced whole-brain computational modelling of the spontaneous dynamics arising from the structural changes in disease, to provide new insights and potentially new targets for hitherto impenetrable neuropsychiatric disorders.

  8. Discontinuous temperature-dependent macroscopic strain due to ferroelastic domain switching and structural phase transitions in barium strontium titanate

    International Nuclear Information System (INIS)

    Remnant strain has been measured as a function of temperature in (Ba0.8Sr0.2)TiO3 (BST) ceramic by mechanical poling in three point bending configuration. BST ceramic exhibits recoverable macroscopic strain with shape memory effect and three jumps in the temperature-dependent strain during thermal cycling under applied force. The jumps are associated with the three structural phase transitions of BST, as confirmed by the simultaneous measurements of dynamic modulus and internal friction. In addition, the orthorhombic phase of BST exhibits a significantly higher strain comparing to that in the tetragonal and rhombohedral phases. X-ray diffraction confirms that the macroscopic strain is due to ferroelastic domain switching and particularly the dominant contribution to the higher macroscopic strain at orthorhombic phase is the higher probability of non-180 deg. domain switching rather than the variation of domain switching strain at different phases