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Sample records for brain structure due

  1. Computational morphometry for detecting changes in brain structure due to development, aging, learning, disease and evolution

    OpenAIRE

    Christian Gaser

    2009-01-01

    The brain, like any living tissue, is constantly changing in response to genetic and environmental cues and their interaction, leading to changes in brain function and structure, many of which are now in reach of neuroimaging techniques. Computational morphometry on the basis of Magnetic Resonance (MR) images has become the method of choice for studying macroscopic changes of brain structure across time scales. Thanks to computational advances and sophisticated study designs, both the minimal...

  2. Computational morphometry for detecting changes in brain structure due to development, aging, learning, disease and evolution

    Directory of Open Access Journals (Sweden)

    Christian Gaser

    2009-08-01

    Full Text Available The brain, like any living tissue, is constantly changing in response to genetic and environmental cues and their interaction, leading to changes in brain function and structure, many of which are now in reach of neuroimaging techniques. Computational morphometry on the basis of Magnetic Resonance (MR images has become the method of choice for studying macroscopic changes of brain structure across time scales. Thanks to computational advances and sophisticated study designs, both the minimal extent of change necessary for detection and, consequently, the minimal periods over which such changes can be detected have been reduced considerably during the last few years. On the other hand, the growing availability of MR images of more and more diverse brain populations also allows more detailed inferences about brain changes that occur over larger time scales, way beyond the duration of an average research project. On this basis, a whole range of issues concerning the structures and functions of the brain are now becoming addressable, thereby providing ample challenges and opportunities for further contributions from neuroinformatics to our understanding of the brain and how it changes over a lifetime and in the course of evolution.

  3. 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.

  4. [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

  5. 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

  6. 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...

  7. 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)

  8. 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.

  9. 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

  10. 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...

  11. 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...

  12. Socioeconomic status and structural brain development

    OpenAIRE

    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 ...

  13. Brain infarcts due to scorpion stings in children: MRI

    International Nuclear Information System (INIS)

    We report two children with severe neurological complications after having been stung by a scorpion. Clinical and MRI findings suggested brain infarcts. The lesions seen were in pons in one child and the right hemisphere in the other. The latter also showed possible hyperemia in the infarcted area. No vascular occlusions were observed and we therefore think the brain infarcts were a consequence of the scorpion sting. The cause of the infarct may be hypotension, shock or depressed left ventricular function, all of which are frequent in severe poisoning by scorpion sting. (orig.)

  14. Brain infarcts due to scorpion stings in children: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Bouzas, A.; Ballesteros-Maresma, A. [Univ. Nacional Autonoma de Mexico, Mexico (Mexico); Morales-Resendiz, M.L. [Hospital General de Queretaro, Mexico (Mexico); Llamas-Ibarra, F. [Clinica Neurologica de Queretaro, Mexico (Mexico); Martinez-Lopez, M. [Fundacion Clinica Medica Sur., Mexico (Mexico)

    2000-02-01

    We report two children with severe neurological complications after having been stung by a scorpion. Clinical and MRI findings suggested brain infarcts. The lesions seen were in pons in one child and the right hemisphere in the other. The latter also showed possible hyperemia in the infarcted area. No vascular occlusions were observed and we therefore think the brain infarcts were a consequence of the scorpion sting. The cause of the infarct may be hypotension, shock or depressed left ventricular function, all of which are frequent in severe poisoning by scorpion sting. (orig.)

  15. 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.

  16. 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

  17. 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.

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

    Science.gov (United States)

    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. 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 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 26/141 (18%) participants assessed at 6 months post-injury. Attention, processing speed, verbal memory, IQ, and executive function, were significantly associated (p < .05) with PC even after socioeconomic status, injury severity, and pre-injury 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. PMID:26185905

  19. 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...

  20. Structural Brain Correlates of Human Sleep Oscillations

    OpenAIRE

    Saletin, Jared M.; van der Helm, Els; Walker, Matthew P.

    2013-01-01

    Sleep is strongly conserved within species, yet marked and perplexing inter-individual differences in sleep physiology are observed. Combining EEG sleep recordings and high-resolution structural brain imaging, here we demonstrate that the morphology of the human brain offers one explanatory factor of such inter-individual variability. Grey matter volume in interoceptive and exteroceptive cortices correlated with the expression of slower NREM sleep spindle frequencies, supporting their propose...

  1. 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

  2. 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...... presented, the optimal linear transform is computed for the input volume (Fischl et al. [2002]: Neuron 33:341-355; Fischl et al. [2004]: Neuroimage 23 (Suppl 1):S69-S84). A brain mask is constructed by forming the union of all voxels with nonzero probability of being brain and then morphologically dilated...... inspection showed none had brain tissue removed. In a detailed analysis of the impact of defacing on skull-stripping, 16 datasets were bias corrected with N3 (Sled et al. [1998]: IEEE Trans Med Imaging 17:87-97), defaced, and then skull-stripped using either a hybrid watershed algorithm (Ségonne et al. [2004...

  3. 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....

  4. 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.)

  5. 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. ...

  6. 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

  7. Structural brain correlates of human sleep oscillations.

    Science.gov (United States)

    Saletin, Jared M; van der Helm, Els; Walker, Matthew P

    2013-12-01

    Sleep is strongly conserved within species, yet marked and perplexing inter-individual differences in sleep physiology are observed. Combining EEG sleep recordings and high-resolution structural brain imaging, here we demonstrate that the morphology of the human brain offers one explanatory factor of such inter-individual variability. Gray matter volume in interoceptive and exteroceptive cortices correlated with the expression of slower NREM sleep spindle frequencies, supporting their proposed role in sleep protection against conscious perception. Conversely, and consistent with an involvement in declarative memory processing, gray matter volume in bilateral hippocampus was associated with faster NREM sleep spindle frequencies. In contrast to spindles, gray matter volume in the homeostatic sleep-regulating center of the basal forebrain/hypothalamus, together with the medial prefrontal cortex, accounted for individual differences in NREM slow wave oscillations. Together, such findings indicate that the qualitative and quantitative expression of human sleep physiology is significantly related to anatomically specific differences in macroscopic brain structure. PMID:23770411

  8. 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.

  9. 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

  10. The structure of creative cognition in the human brain

    Directory of Open Access Journals (Sweden)

    Rex Eugene Jung

    2013-07-01

    Full Text Available Creativity is a vast construct, seemingly intractable to scientific inquiry – perhaps due to the vague concepts applied to the field of research. One attempt to limit the purview of creative cognition formulates the construct in terms of evolutionary constraints, namely that of blind variation and selective retention (BVSR. Behaviorally, one can limit the “blind variation” component to idea generation tests as manifested by measures of divergent thinking. The “selective retention” component can be represented by measures of convergent thinking, as represented by measures of remote associates. We summarize results from measures of creative cognition, correlated with structural neuroimaging measures including structural magnetic resonance imaging (sMRI, Diffusion Tensor Imaging (DTI, and proton magnetic resonance imaging (1H-MRS. We also review lesion studies, considered to be the “gold standard” of brain-behavioral studies. What emerges is a picture consistent with theories of disinhibitory brain features subserving creative cognition, as described previously (Martindale, 1981. We provide a perspective, involving aspects of the default mode network, which might provide a “first approximation” regarding how creative cognition might map on to the human brain.

  11. 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. PMID:26185905

  12. Common genetic variants influence human subcortical brain structures

    OpenAIRE

    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

    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...

  13. Common genetic variants influence human subcortical brain structures

    OpenAIRE

    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

    2015-01-01

    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 magn...

  14. 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...

  15. [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

  16. Predictors of Personality Change Due to Traumatic Brain Injury in Children and Adolescents in the First Six Months after Injury.

    Science.gov (United States)

    Max, Jeffrey E.; Levin, Harvey S.; Landis, Julie; Schachar, Russell; Saunders, Ann; Ewing-Cobbs, Linda; Chapman, Sandra B.; Dennis, Maureen

    2005-01-01

    Objective: To assess the phenomenology and predictive factors of personality change due to traumatic brain injury. Method: Children (N = 177), aged 5 to 14 years with traumatic brain injury from consecutive admissions to five trauma centers, were followed prospectively at baseline and 6 months with semistructured psychiatric interviews. Injury…

  17. Building damage due to structural pounding during earthquakes

    Science.gov (United States)

    Sołtysik, B.; Jankowski, R.

    2015-07-01

    Earthquake-induced pounding between adjacent buildings has been identified as one of the reasons for substantial damage or even total collapse of colliding structures. A major reason leading to interactions in buildings results from the differences in their dynamic parameters and also from insufficient distance between the structures. Although the research on structural pounding has been much advanced, the studies have mainly been conducted for concrete structures. The aim of this paper is to show the results of the non-linear numerical analysis focuses on damage due to pounding between two steel buildings under earthquake excitation. The numerical analysis has been performed using models of steel asymmetric structures with different number of storeys which makes them vibrate out-of-phase. Pounding between buildings has been controlled using three-dimensional gap-friction elements which become active when contact is detected. In order to identify the dynamic characteristics of analyzed structures, the modal analysis has been first conducted. Then, the detailed non-linear dynamic analysis of colliding structures has been performed. The acceleration time histories of the El Centro earthquake have been used in the numerical analysis. The results of the study clearly indicate that pounding may substantially influence the response of steel buildings intensifying their damage during earthquakes.

  18. Shoreline change due to coastal structures of power plants

    International Nuclear Information System (INIS)

    Characteristics of shoreline change at the coastal area near power plant were analyzed. For a nuclear power plant located in the east coast of Korean peninsula, remote-sensing data, i.e.airborne images and satellite images are acquired and shoreline data were extracted. Recession and davance of shoreline due to coastal structures of powder plant and land reclamation was showed. 1-line numerical shoreline change model was established for simulating the response of shoreline to construction of coastal structures. The model uses curvilinear coordinates that follow the shoreline and is capable of handling the formation of tombolos as well as the growth of salients in the vicinity of coastal structures. The model predicted significant erosion of beach in case breakwaters were extended. Offshore breakwaters were suggested as a countermeasure to shoreline change

  19. 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.

  20. Structural Brain Network: What is the Effect of LiFE Optimization of Whole Brain Tractography?

    OpenAIRE

    Qi, Shouliang; Meesters, Stephan; Nicolay, Klaas; ter Haar Romeny, Bart M.; Ossenblok, Pauly

    2016-01-01

    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 co...

  1. Brain structure links everyday creativity to creative achievement.

    Science.gov (United States)

    Zhu, Wenfeng; Chen, Qunlin; Tang, Chaoying; Cao, Guikang; Hou, Yuling; Qiu, Jiang

    2016-03-01

    Although creativity is commonly considered to be a cornerstone of human progress and vital to all realms of our lives, its neural basis remains elusive, partly due to the different tasks and measurement methods applied in research. In particular, the neural correlates of everyday creativity that can be experienced by everyone, to some extent, are still unexplored. The present study was designed to investigate the brain structure underlying individual differences in everyday creativity, as measured by the Creative Behavioral Inventory (CBI) (N=163). The results revealed that more creative activities were significantly and positively associated with larger gray matter volume (GMV) in the regional premotor cortex (PMC), which is a motor planning area involved in the creation and selection of novel actions and inhibition. In addition, the gray volume of the PMC had a significant positive relationship with creative achievement and Art scores, which supports the notion that training and practice may induce changes in brain structures. These results indicate that everyday creativity is linked to the PMC and that PMC volume can predict creative achievement, supporting the view that motor planning may play a crucial role in creative behavior. PMID:26855062

  2. 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 ...

  3. 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

  4. 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 ...

  5. Structural Brain Changes in Chronic Pain Reflect Probably Neither Damage Nor Atrophy

    OpenAIRE

    Rodriguez-Raecke, Rea; Niemeier, Andreas; Ihle, Kristin; Ruether, Wolfgang; May, Arne

    2013-01-01

    Chronic pain appears to be associated with brain gray matter reduction in areas ascribable to the transmission of pain. The morphological processes underlying these structural changes, probably following functional reorganisation and central plasticity in the brain, remain unclear. The pain in hip osteoarthritis is one of the few chronic pain syndromes which are principally curable. We investigated 20 patients with chronic pain due to unilateral coxarthrosis (mean age 63.25±9.46 (SD) years, 1...

  6. 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

  7. 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

  8. 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

  9. 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

    2015-06-01

    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 multimodal integration of brain structure and function analyses links sexual and nonsexual psychopathology in pedophilia. PMID:25733379

  10. Asymmetry of the Structural Brain Connectome in Healthy Older Adults

    OpenAIRE

    Bonilha, Leonardo; Nesland, Travis; Rorden, Chris; Fridriksson, Julius

    2014-01-01

    Background: It is now possible to map neural connections in vivo across the whole brain (i.e., the brain connectome). This is a promising development in neuroscience since many health and disease processes are believed to arise from the architecture of neural networks. Objective: To describe the normal range of hemispheric asymmetry in structural connectivity in healthy older adults. Materials and Methods: We obtained high-resolution structural magnetic resonance images (MRI) from 17 he...

  11. 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...

  12. 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

  13. 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.

  14. Brain structural and functional alterations in patients with unilateral hearing loss.

    Science.gov (United States)

    Yang, Ming; Chen, Hua-Jun; Liu, Bin; Huang, Zhi-Chun; Feng, Yuan; Li, Jing; Chen, Jing-Ya; Zhang, Ling-Ling; Ji, Hui; Feng, Xu; Zhu, Xin; Teng, Gao-Jun

    2014-10-01

    Alterations of brain structure and functional connectivity have been described in patients with hearing impairments due to distinct pathogenesis; however, the influence of unilateral hearing loss (UHL) on brain morphology and regional brain activity is still not completely understood. In this study, we aim to investigate regional brain structural and functional alterations in patients with UHL. T1-weighted volumetric images and task-free fMRIs were acquired from 14 patients with right-sided UHL (pure tone average ≥ 40 dB HL) and 19 healthy controls. Hearing ability was assessed by pure tone audiometry. Voxel-based morphometry (VBM) was performed to detect brain regions with changed gray matter volume or white matter volume in UHL. The amplitude of low-frequency fluctuation (ALFF) was calculated to analyze brain activity at the baseline and was compared between two groups. Compared with controls, UHL patients showed decreased gray matter volume in bilateral posterior cingulate gyrus and precuneus, left superior/middle/inferior temporal gyrus, and right parahippocampal gyrus and lingual gyrus. Meanwhile, patients showed significantly decreased ALFF in bilateral precuneus, left inferior parietal lobule, and right inferior frontal gyrus and insula and increased ALFF in right inferior and middle temporal gyrus. These findings suggest that chronic UHL could induce brain morphological changes and is associated with aberrant baseline brain activity. PMID:25093284

  15. 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.

  16. Understanding the brain through its spatial structure

    Science.gov (United States)

    Morrison, Will Zachary

    The spatial location of cells in neural tissue can be easily extracted from many imaging modalities, but the information contained in spatial relationships between cells is seldom utilized. This is because of a lack of recognition of the importance of spatial relationships to some aspects of brain function, and the reflection in spatial statistics of other types of information. The mathematical tools necessary to describe spatial relationships are also unknown to many neuroscientists, and biologists in general. We analyze two cases, and show that spatial relationships can be used to understand the role of a particular type of cell, the astrocyte, in Alzheimer's disease, and that the geometry of axons in the brain's white matter sheds light on the process of establishing connectivity between areas of the brain. Astrocytes provide nutrients for neuronal metabolism, and regulate the chemical environment of the brain, activities that require manipulation of spatial distributions (of neurotransmitters, for example). We first show, through the use of a correlation function, that inter-astrocyte forces determine the size of independent regulatory domains in the cortex. By examining the spatial distribution of astrocytes in a mouse model of Alzheimer's Disease, we determine that astrocytes are not actively transported to fight the disease, as was previously thought. The paths axons take through the white matter determine which parts of the brain are connected, and how quickly signals are transmitted. The rules that determine these paths (i.e. shortest distance) are currently unknown. By measurement of axon orientation distributions using three-point correlation functions and the statistics of axon turning and branching, we reveal that axons are restricted to growth in three directions, like a taxicab traversing city blocks, albeit in three-dimensions. We show how geometric restrictions at the small scale are related to large-scale trajectories. Finally we discuss the

  17. 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.

  18. 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...

  19. Evaluation of linear registration algorithms for brain SPECT and the errors due to hypoperfusion lesions

    International Nuclear Information System (INIS)

    The semiquantitative analysis of perfusion single-photon emission computed tomography (SPECT) images requires a reproducible, objective method. Automated spatial standardization (registration) of images is a prerequisite to this goal. A source of registration error is the presence of hypoperfusion defects, which was evaluated in this study with simulated lesions. The brain perfusion images measured by 99mTc-HMPAO SPECT from 21 patients with probable Alzheimer's disease and 35 control subjects were retrospectively analyzed. An automatic segmentation method was developed to remove external activity. Three registration methods, robust least squares, normalized mutual information (NMI), and count difference were implemented and the effects of simulated defects were compared. The tested registration methods required segmentation of the cerebrum from external activity, and the automatic and manual methods differed by a three-dimensional displacement of 1.4±1.1 mm. NMI registration proved to be least adversely effected by simulated defects with 3 mm average displacement caused by severe defects. The error in quantifying the patient-template parietal ratio due to misregistration was 2.0% for large defects (70% hypoperfusion) and 0.5% for smaller defects (85% hypoperfusion)

  20. The consequences of fetal growth restriction on brain structure and neurodevelopmental outcome.

    Science.gov (United States)

    Miller, Suzanne L; Huppi, Petra S; Mallard, Carina

    2016-02-15

    Fetal growth restriction (FGR) is a significant complication of pregnancy describing a fetus that does not grow to full potential due to pathological compromise. FGR affects 3-9% of pregnancies in high-income countries, and is a leading cause of perinatal mortality and morbidity. Placental insufficiency is the principal cause of FGR, resulting in chronic fetal hypoxia. This hypoxia induces a fetal adaptive response of cardiac output redistribution to favour vital organs, including the brain, and is in consequence called brain sparing. Despite this, it is now apparent that brain sparing does not ensure normal brain development in growth-restricted fetuses. In this review we have brought together available evidence from human and experimental animal studies to describe the complex changes in brain structure and function that occur as a consequence of FGR. In both humans and animals, neurodevelopmental outcomes are influenced by the timing of the onset of FGR, the severity of FGR, and gestational age at delivery. FGR is broadly associated with reduced total brain volume and altered cortical volume and structure, decreased total number of cells and myelination deficits. Brain connectivity is also impaired, evidenced by neuronal migration deficits, reduced dendritic processes, and less efficient networks with decreased long-range connections. Subsequent to these structural alterations, short- and long-term functional consequences have been described in school children who had FGR, most commonly including problems in motor skills, cognition, memory and neuropsychological dysfunctions. PMID:26607046

  1. 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...

  2. 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.)

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

    International Nuclear Information System (INIS)

    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.)

  4. 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

  5. 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.

    2015-01-01

    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

  6. 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

  7. Using computational models to relate structural and functional brain connectivity

    Czech Academy of Sciences Publication Activity Database

    Hlinka, Jaroslav; Coombes, S.

    2012-01-01

    Roč. 36, č. 2 (2012), s. 2137-2145. ISSN 0953-816X R&D Projects: GA MŠk 7E08027 EU Projects: European Commission(XE) 200728 - BRAIN SYNC Institutional research plan: CEZ:AV0Z10300504 Keywords : brain disease * computational modelling * functional connectivity * graph theory * structural connectivity Subject RIV: FH - Neurology Impact factor: 3.753, year: 2012

  8. 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...

  9. 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

  10. 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.

  11. Nonlinear drift wave instability due to nonlinear structures

    International Nuclear Information System (INIS)

    A nonlinear instability due to zonal flows and magnetic islands has been found. The instability has the character of a dissipative drift instability due to an anomalous resistivity. The anomalous resistivity is typically two orders of magnitude larger than the classical at the edge. (author)

  12. Effects of Soccer Heading on Brain Structure and Function.

    Science.gov (United States)

    Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo

    2016-01-01

    Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player's unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6-12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety

  13. 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

  14. Detection of brain atrophy due to ACTH or corticosteroid therapy with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tamai, I.; Takei, T. (National Sagamihara Hospital, Kanagawa (Japan)); Oota, H.; Maekawa, K.

    1981-07-01

    Adrenocorticotropic hormone (ACTH) or corticosteroids seemed to cause brain atrophy in infants. We studied the atrophy which was caused by these drugs with computed tomography (CT). 1) Nine cases of infantile spasms examined before, during and after ACTH therapy with CT. Brain atrophy on CT was observed immediately after the completion of ACTH therapy. The brain atrophy receded slightly after several months. It was more marked in younger patients, in cases treated by high doses of ACTH and in cases where brain atrophy had already been observed before ACTH therapy. 2) Twenty cases of infantile spasms or Lennox Gastaut syndrome were examined after ACTH therapy with CT. Brain atrophy was observed in twelve cases. Main features of brain atrophy were the enlargement of sylvian fissure and the widening of subarachnoid space at the frontal or temporal region. Mental retardation was observed in eighteen cases. 3) Two cases of nephrotic syndrome were treated with pulse therapy of prednisolone. CT was carried out before and after treatment. Atrophy of cerebrum was observed in these cases. 4) A case of infantile spasms treated with anticonvulsants without ACTH was studied by electroencephalography (EEG) and CT. The abnormal pattern of EEG was markedly corrected, while brain atrophy on CT was not observed after the therapy. Because of these observations the use of ACTH has to be reconsidered. ACTH should be the drug of second choice for the therapy of infantile spasms and should be used in case other anticonvulsants have no effect. ACTH should be used at lower dosages and for shorter periods of time.

  15. Estimating brain's functional graph from the structural graph's Laplacian

    Science.gov (United States)

    Abdelnour, F.; Dayan, M.; Devinsky, O.; Thesen, T.; Raj, A.

    2015-09-01

    The interplay between the brain's function and structure has been of immense interest to the neuroscience and connectomics communities. In this work we develop a simple linear model relating the structural network and the functional network. We propose that the two networks are related by the structural network's Laplacian up to a shift. The model is simple to implement and gives accurate prediction of function's eigenvalues at the subject level and its eigenvectors at group level.

  16. 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.

  17. Structural brain changes in chronic pain reflect probably neither damage nor atrophy.

    Directory of Open Access Journals (Sweden)

    Rea Rodriguez-Raecke

    Full Text Available Chronic pain appears to be associated with brain gray matter reduction in areas ascribable to the transmission of pain. The morphological processes underlying these structural changes, probably following functional reorganisation and central plasticity in the brain, remain unclear. The pain in hip osteoarthritis is one of the few chronic pain syndromes which are principally curable. We investigated 20 patients with chronic pain due to unilateral coxarthrosis (mean age 63.25±9.46 (SD years, 10 female before hip joint endoprosthetic surgery (pain state and monitored brain structural changes up to 1 year after surgery: 6-8 weeks, 12-18 weeks and 10-14 month when completely pain free. Patients with chronic pain due to unilateral coxarthrosis had significantly less gray matter compared to controls in the anterior cingulate cortex (ACC, insular cortex and operculum, dorsolateral prefrontal cortex (DLPFC and orbitofrontal cortex. These regions function as multi-integrative structures during the experience and the anticipation of pain. When the patients were pain free after recovery from endoprosthetic surgery, a gray matter increase in nearly the same areas was found. We also found a progressive increase of brain gray matter in the premotor cortex and the supplementary motor area (SMA. We conclude that gray matter abnormalities in chronic pain are not the cause, but secondary to the disease and are at least in part due to changes in motor function and bodily integration.

  18. 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

  19. 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...

  20. 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.

  1. 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

  2. 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 MRI data and reveal shape changes that may be due to preterm birth.

  3. 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)

  4. 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

  5. Emergence of cognitive deficits after mild traumatic brain injury due to hyperthermia.

    Science.gov (United States)

    Titus, David J; Furones, Concepcion; Atkins, Coleen M; Dietrich, W Dalton

    2015-01-01

    Mild elevations in core temperature can occur in individuals involved in strenuous activities that are risky for potentially sustaining a mild traumatic brain injury (mTBI) or concussion. Recently, we have discovered that mild elevations in brain temperature can significantly aggravate the histopathological consequences of mTBI. However, whether this exacerbation of brain pathology translates into behavioral deficits is unknown. Therefore, we investigated the behavioral consequences of elevating brain temperature to mildly hyperthermic levels prior to mTBI. Adult male Sprague Dawley rats underwent mild fluid-percussion brain injury or sham surgery while normothermic (37 °C) or hyperthermic (39 °C) and were allowed to recover for 7 days. Animals were then assessed for cognition using the water maze and cue and contextual fear conditioning. We found that mTBI alone at normothermia had no effect on long-term cognitive measures whereas mTBI animals that were hyperthermic for 15 min prior to and for 4h after brain injury were significantly impaired on long-term retention for both the water maze and fear conditioning. In contrast, hyperthermic mTBI animals cooled within 15 min to normothermia demonstrated no significant long-term cognitive deficits. Mild TBI irrespective of temperature manipulations resulted in significant short-term working memory deficits. Cortical atrophy and contusions were detected in all mTBI treatment groups and contusion volume was significantly less in hyperthermic mTBI animals that were cooled as compared to hyperthermic mTBI animals that remained hyperthermic. These results indicate that brain temperature is an important variable for mTBI outcome and that mildly elevated temperatures at the time of injury result in persistent cognitive deficits. Importantly, cooling to normothermia after mTBI prevents the development of long-term cognitive deficits caused by hyperthermia. Reducing temperature to normothermic levels soon after mTBI represents

  6. Modeling of Discontinuities in Resistance Structures due to Corrosion

    Directory of Open Access Journals (Sweden)

    Daniel Boboş

    2011-05-01

    Full Text Available The corrosion process is a process that produces significant negative effects on the resistance structures by reducing their section and by deterioration of mechanical properties of materials. In this paper are presented some notions about the corrosion process, types of corrosion encountered and types of geometric models that can be used for analytical calculation and for numerical simulation using finite element analysis programs, of the effects produced in the corrosion process on the natural frequency of the structure elements.

  7. 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

  8. Brain Structure Abnormalities in Adolescent Girls with Conduct Disorder

    Science.gov (United States)

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

    2013-01-01

    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.…

  9. 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…

  10. 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.

  11. 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...

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

    Directory of Open Access Journals (Sweden)

    Sophia Frangou

    2012-01-01

    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 genotype.

  13. 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...

  14. Regional ADC values of the normal brain: differences due to age, gender, and laterality

    Energy Technology Data Exchange (ETDEWEB)

    Naganawa, Shinji; Ishigaki, Takeo [Department of Radiology, Nagoya University School of Medicine, 65 Tsurumai-cho, Shouwa-ku, Nagoya 466-8550 (Japan); Sato, Kimihide; Katagiri, Toshio; Mimura, Takeo [Department of Radiology, First Kamiida General Hospital (Japan)

    2003-01-01

    The purpose of this study was to evaluate the stability of measurement for apparent diffusion coefficient (ADC) values in normal brain, to clarify the effect of aging on ADC values, to compare ADC values between men and women, and to compare ADC values between right and left sides of the brain. To evaluate the stability of measurements, five normal volunteers (four men and one woman) were examined five times on different days. Then, 294 subjects with normal MR imaging (147 men and 147 women; age range 20-89 years) were measured. The ADC measurement in normal volunteers was stable. The ADC values stayed within the 5% deviation of average values in all volunteers (mean{+-}standard deviation 2.3{+-}1.2%). The ADC values gradually increased by aging in all regions. In thalamus, no significant difference was seen between right and left in the subjects under 60 years; however, right side showed higher values in the subjects over 60 years (p<0.01). In the subjects under 60 years, women showed higher values in right frontal, bilateral thalamus, and temporal (p<0.01); however, in the subjects over 60 years, no region showed difference between men and women. The knowledge obtained in this study may be helpful to understand the developmental and aging mechanisms of normal brain and may be useful for the future quantitative study as a reference. (orig.)

  15. Regional ADC values of the normal brain: differences due to age, gender, and laterality

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the stability of measurement for apparent diffusion coefficient (ADC) values in normal brain, to clarify the effect of aging on ADC values, to compare ADC values between men and women, and to compare ADC values between right and left sides of the brain. To evaluate the stability of measurements, five normal volunteers (four men and one woman) were examined five times on different days. Then, 294 subjects with normal MR imaging (147 men and 147 women; age range 20-89 years) were measured. The ADC measurement in normal volunteers was stable. The ADC values stayed within the 5% deviation of average values in all volunteers (mean±standard deviation 2.3±1.2%). The ADC values gradually increased by aging in all regions. In thalamus, no significant difference was seen between right and left in the subjects under 60 years; however, right side showed higher values in the subjects over 60 years (p<0.01). In the subjects under 60 years, women showed higher values in right frontal, bilateral thalamus, and temporal (p<0.01); however, in the subjects over 60 years, no region showed difference between men and women. The knowledge obtained in this study may be helpful to understand the developmental and aging mechanisms of normal brain and may be useful for the future quantitative study as a reference. (orig.)

  16. 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.

  17. Altered Structural Brain Networks in Tuberous Sclerosis Complex.

    Science.gov (United States)

    Im, Kiho; Ahtam, Banu; Haehn, Daniel; Peters, Jurriaan M; Warfield, Simon K; Sahin, Mustafa; Ellen Grant, P

    2016-05-01

    Tuberous sclerosis complex (TSC) is characterized by benign hamartomas in multiple organs including the brain and its clinical phenotypes may be associated with abnormal neural connections. We aimed to provide the first detailed findings on disrupted structural brain networks in TSC patients. Structural whole-brain connectivity maps were constructed using structural and diffusion MRI in 20 TSC (age range: 3-24 years) and 20 typically developing (TD; 3-23 years) subjects. We assessed global (short- and long-association and interhemispheric fibers) and regional white matter connectivity, and performed graph theoretical analysis using gyral pattern- and atlas-based node parcellations. Significantly higher mean diffusivity (MD) was shown in TSC patients than in TD controls throughout the whole brain and positively correlated with tuber load severity. A significant increase in MD was mainly influenced by an increase in radial diffusivity. Furthermore, interhemispheric connectivity was particularly reduced in TSC, which leads to increased network segregation within hemispheres. TSC patients with developmental delay (DD) showed significantly higher MD than those without DD primarily in intrahemispheric connections. Our analysis allows non-biased determination of differential white matter involvement, which may provide better measures of "lesion load" and lead to a better understanding of disease mechanisms. PMID:25750257

  18. 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

  19. 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

  20. 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

  1. 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

  2. Magnetoresistance due to domain walls in semiconducting magnetic nano structures

    International Nuclear Information System (INIS)

    Magnetoresistance of a semiconducting ferromagnetic nano structure with a laterally constrained domain wall is analyzed theoretically in the limit of sharp domain walls and fully polarized electron gas is considered. The spin-orbit interaction of Rash ba type is included into considerations. It is shown that the magnetoresistance in such a case can be relatively large, which is in a qualitative agreement with recent experimental observations. It is also shown that spin-orbit interaction can enhance the magnetoresistance. The role of localization corrections is also briefly discussed

  3. Magnetoresistance due to domain walls in semiconducting magnetic nano structures

    Energy Technology Data Exchange (ETDEWEB)

    Dugaev, V.K. [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany) and Institute for Problems of Materials Science, Vilde 5, 58001 Chernovtsy (Ukraine)]. E-mail: vdugaev@mpi-halle.de; Berakdar, J. [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany); Barnas, J. [Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznan, and Institute of Molecular Physics PAN, ul. M. Smoluchowskiego 17, 60-179 Poznan (Poland); Dobrowolski, W. [Institute of Physics PAN, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Mitin, V.F. [Institute of Semiconductor Physics, NANU, pr. Nauki, 03108 Kiev (Ukraine); Vieira, M. [ISEL-DEETC, Rua Cons. Emidio Navarro, 1950-062 Lisbon (Portugal)

    2005-12-15

    Magnetoresistance of a semiconducting ferromagnetic nano structure with a laterally constrained domain wall is analyzed theoretically in the limit of sharp domain walls and fully polarized electron gas is considered. The spin-orbit interaction of Rash ba type is included into considerations. It is shown that the magnetoresistance in such a case can be relatively large, which is in a qualitative agreement with recent experimental observations. It is also shown that spin-orbit interaction can enhance the magnetoresistance. The role of localization corrections is also briefly discussed.

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

    Science.gov (United States)

    Wolff, C.; Van Laer, R.; Steel, M. J.; Eggleton, B. J.; Poulton, C. G.

    2016-02-01

    We study the impact of structural variations (that is slowly varying geometry aberrations and internal strain fields) on the width and shape of the stimulated Brillouin scattering (SBS) resonance 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. Finally, we illustrate in a numerical example that in backward SBS and inter-mode forward SBS the existence of two broadening mechanisms with opposite sign also opens the possibility to compensate the effect of geometry-induced broadening. Our results can be transferred to other micro- and nano-structured waveguide geometries such as photonic crystal fibres.

  5. 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

  6. Structural changes in the brain according to CT findings in children with long-term consequences of closed brain injury

    International Nuclear Information System (INIS)

    Long-term structural changes in the brain substance after closed brain injury (CBI) in children using computerized tomography was studied. 30 patients aged 11-18 with CBI with favourable and unfavourable course was examined. The obtained findings suggest a complicated picture of the reaction of the involved brain. The degree of neurologic signs and the type of traumatic injuries depend on the degree of structural changes

  7. 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.

  8. Fluid transport due to nonlinear fluid-structure interaction

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard

    1997-01-01

    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 unidirectional 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 analysed numerically and by the use of a perturbation method (multiple scales). Exciting the pipe in the fundamental mode of vibration seems to be most effective for transferring energy from the shaker to the fluid......, whereas higher modes of vibration can be used to transport fluid with pipe vibrations of smaller amplitude. The effect of the nonlinear geometrical terms is analysed and these terms are shown to affect the response for higher modes of vibration. Experimental investigations show good agreement with...

  9. 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...

  10. VLBI height corrections due to gravitational deformation of antenna structures

    Science.gov (United States)

    Sarti, P.; Negusini, M.; Abbondanza, C.; Petrov, L.

    2009-12-01

    From an analysis of regional European VLBI data we evaluate the impact of a VLBI signal path correction model developed to account for gravitational deformations of the antenna structures. The model was derived from a combination of terrestrial surveying methods applied to telescopes at Medicina and Noto in Italy. We find that the model corrections shift the derived height components of these VLBI telescopes' reference points downward by 14.5 and 12.2 mm, respectively. No other parameter estimates nor other station positions are affected. Such systematic height errors are much larger than the formal VLBI random errors and imply the possibility of significant VLBI frame scale distortions, of major concern for the International Terrestrial Reference Frame (ITRF) and its applications. This demonstrates the urgent need to investigate gravitational deformations in other VLBI telescopes and eventually correct them in routine data analysis.

  11. Mesoscopic structure formation in condensed matter due to vacuum fluctuations

    Science.gov (United States)

    Sen, Siddhartha; Gupta, Kumar S.; Coey, J. M. D.

    2015-10-01

    An observable influence of zero-point fluctuations of the vacuum electromagnetic field on bound electrons is well known in the hydrogen atom, where it produces the Lamb shift. Here, we adapt an approach used to explain the Lamb shift in terms of a slight expansion of the orbits due to interaction with the zero-point field and apply it to assemblies of N electrons that are modeled as independent atomically bound two-level systems. The effect is to stabilize a collective ground-state energy, which leads to a prediction of novel effects at room temperature for quasi-two-dimensional systems over a range of parameters in the model, namely, N , the two-level excitation energy ℏ ω and the ionization energy ℏ ω +ɛ . Some mesoscopic systems where these effects may be observable include water sheaths on protein or DNA, surfaces of gaseous nanobubbles, and the magnetic response of inhomogeneous, electronically dilute oxides. No such effects are envisaged for uniform three-dimensional systems.

  12. 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

  13. Impact of fatty acids on brain circulation, structure and function.

    Science.gov (United States)

    Haast, Roy A M; Kiliaan, Amanda J

    2015-01-01

    The use of dietary intervention has evolved into a promising approach to prevent the onset and progression of brain diseases. The positive relationship between intake of omega-3 long chain polyunsaturated fatty acids (ω3-LCPUFAs) and decreased onset of disease- and aging-related deterioration of brain health is increasingly endorsed across epidemiological and diet-interventional studies. Promising results are found regarding to the protection of proper brain circulation, structure and functionality in healthy and diseased humans and animal models. These include enhanced cerebral blood flow (CBF), white and gray matter integrity, and improved cognitive functioning, and are possibly mediated through increased neurovascular coupling, neuroprotection and neuronal plasticity, respectively. Contrary, studies investigating diets high in saturated fats provide opposite results, which may eventually lead to irreversible damage. Studies like these are of great importance given the high incidence of obesity caused by the increased and decreased consumption of respectively saturated fats and ω3-LCPUFAs in the Western civilization. This paper will review in vivo research conducted on the effects of ω3-LCPUFAs and saturated fatty acids on integrity (circulation, structure and function) of the young, aging and diseased brain. PMID:24485516

  14. Structural and functional brain changes in delusional disorder.

    Science.gov (United States)

    Vicens, Victor; Radua, Joaquim; Salvador, Raymond; Anguera-Camós, Maria; Canales-Rodríguez, Erick J; Sarró, Salvador; Maristany, Teresa; McKenna, Peter J; Pomarol-Clotet, Edith

    2016-02-01

    BackgroundDelusional disorder has been the subject of very little investigation using brain imaging.AimsTo examine potential structural and/or functional brain abnormalities in this disorder.MethodWe used structural imaging (voxel-based morphometry, VBM) and functional imaging (during performance of the n-back task and whole-brain resting connectivity analysis) to examine 22 patients meeting DSM-IV criteria for delusional disorder and 44 matched healthy controls.ResultsThe patients showed grey matter reductions in the medial frontal/anterior cingulate cortex and bilateral insula on unmodulated (but not on modulated) VBM analysis, failure of de-activation in the medial frontal/anterior cingulate cortex during performance of the n-back task, and decreased resting-state connectivity in the bilateral insula.ConclusionsThe findings provide evidence of brain abnormality in the medial frontal/anterior cingulate cortex and insula in delusional disorder. A role for the former region in the pathogenesis of delusions is consistent with several other lines of evidence. PMID:26382955

  15. 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

  16. Joint Modelling of Structural and Functional Brain Networks

    DEFF Research Database (Denmark)

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

    -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....

  17. Oxidative Stress in the Developing Rat Brain due to Production of Reactive Oxygen and Nitrogen Species

    Science.gov (United States)

    Wilhelm, Jiří; Vytášek, Richard; Uhlík, Jiří; Vajner, Luděk

    2016-01-01

    Oxidative stress after birth led us to localize reactive oxygen and nitrogen species (RONS) production in the developing rat brain. Brains were assessed a day prenatally and on postnatal days 1, 2, 4, 8, 14, 30, and 60. Oxidation of dihydroethidium detected superoxide; 6-carboxy-2′,7′-dichlorodihydrofluorescein diacetate revealed hydrogen peroxide; immunohistochemical proof of nitrotyrosine and carboxyethyllysine detected peroxynitrite formation and lipid peroxidation, respectively. Blue autofluorescence detected protein oxidation. The foetuses showed moderate RONS production, which changed cyclically during further development. The periods and sites of peak production of individual RONS differed, suggesting independent generation. On day 1, neuronal/glial RONS production decreased indicating that increased oxygen concentration after birth did not cause oxidative stress. Dramatic changes in the amount and the sites of RONS production occurred on day 4. Nitrotyrosine detection reached its maximum. Day 14 represented other vast alterations in RONS generation. Superoxide production in arachnoidal membrane reached its peak. From this day on, the internal elastic laminae of blood vessels revealed the blue autofluorescence. The adult animals produced moderate levels of superoxide; all other markers reached their minimum. There was a strong correlation between detection of nitrotyrosine and carboxyethyllysine probably caused by lipid peroxidation initiated with RONS.

  18. Discovering anatomical patterns with pathological meaning by clustering of visual primitives in structural brain MRI

    Science.gov (United States)

    Leon, Juan; Pulido, Andrea; Romero, Eduardo

    2015-01-01

    Computational anatomy is a subdiscipline of the anatomy that studies macroscopic details of the human body structure using a set of automatic techniques. Different reference systems have been developed for brain mapping and morphometry in functional and structural studies. Several models integrate particular anatomical regions to highlight pathological patterns in structural brain MRI, a really challenging task due to the complexity, variability, and nonlinearity of the human brain anatomy. In this paper, we present a strategy that aims to find anatomical regions with pathological meaning by using a probabilistic analysis. Our method starts by extracting visual primitives from brain MRI that are partitioned into small patches and which are then softly clustered, forming different regions not necessarily connected. Each of these regions is described by a co- occurrence histogram of visual features, upon which a probabilistic semantic analysis is used to find the underlying structure of the information, i.e., separated regions by their low level similarity. The proposed approach was tested with the OASIS data set which includes 69 Alzheimer's disease (AD) patients and 65 healthy subjects (NC).

  19. An examination of cetacean brain structure with a novel hypothesis correlating thermogenesis to the evolution of a big brain.

    Science.gov (United States)

    Manger, Paul R

    2006-05-01

    This review examines aspects of cetacean brain structure related to behaviour and evolution. Major considerations include cetacean brain-body allometry, structure of the cerebral cortex, the hippocampal formation, specialisations of the cetacean brain related to vocalisations and sleep phenomenology, paleoneurology, and brain-body allometry during cetacean evolution. These data are assimilated to demonstrate that there is no neural basis for the often-asserted high intellectual abilities of cetaceans. Despite this, the cetaceans do have volumetrically large brains. A novel hypothesis regarding the evolution of large brain size in cetaceans is put forward. It is shown that a combination of an unusually high number of glial cells and unihemispheric sleep phenomenology make the cetacean brain an efficient thermogenetic organ, which is needed to counteract heat loss to the water. It is demonstrated that water temperature is the major selection pressure driving an altered scaling of brain and body size and an increased actual brain size in cetaceans. A point in the evolutionary history of cetaceans is identified as the moment in which water temperature became a significant selection pressure in cetacean brain evolution. This occurred at the Archaeoceti - modern cetacean faunal transition. The size, structure and scaling of the cetacean brain continues to be shaped by water temperature in extant cetaceans. The alterations in cetacean brain structure, function and scaling, combined with the imperative of producing offspring that can withstand the rate of heat loss experienced in water, within the genetic confines of eutherian mammal reproductive constraints, provides an explanation for the evolution of the large size of the cetacean brain. These observations provide an alternative to the widely held belief of a correlation between brain size and intelligence in cetaceans. PMID:16573845

  20. Structural brain alterations associated with dyslexia predate reading onset.

    Science.gov (United States)

    Raschle, Nora Maria; Chang, Maria; Gaab, Nadine

    2011-08-01

    Functional magnetic resonance imaging studies have reported reduced activation in parietotemporal and occipitotemporal areas in adults and children with developmental dyslexia compared to controls during reading and reading related tasks. These patterns of regionally reduced activation have been linked to behavioral impairments of reading-related processes (e.g., phonological skills and rapid automatized naming). The observed functional and behavioral differences in individuals with developmental dyslexia have been complemented by reports of reduced gray matter in left parietotemporal, occipitotemporal areas, fusiform and lingual gyrus and the cerebellum. An important question for education is whether these neural differences are present before reading is taught. Developmental dyslexia can only be diagnosed after formal reading education starts. However, here we investigate whether the previously detected gray matter alterations in adults and children with developmental dyslexia can already be observed in a small group of pre-reading children with a family-history of developmental dyslexia compared to age and IQ-matched children without a family-history (N = 20/mean age: 5:9 years; age range 5:1-6:5 years). Voxel-based morphometry revealed significantly reduced gray matter volume indices for pre-reading children with, compared to children without, a family-history of developmental dyslexia in left occipitotemporal, bilateral parietotemporal regions, left fusiform gyrus and right lingual gyrus. Gray matter volume indices in left hemispheric occipitotemporal and parietotemporal regions of interest also correlated positively with rapid automatized naming. No differences between the two groups were observed in frontal and cerebellar regions. This discovery in a small group of children suggests that previously described functional and structural alterations in developmental dyslexia may not be due to experience-dependent brain changes but may be present at birth or

  1. 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.

  2. 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 ...

  3. 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

  4. 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

  5. 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.

  6. On the pressure response in the brain due to short duration blunt impacts.

    Directory of Open Access Journals (Sweden)

    Christopher W Pearce

    Full Text Available When the head is subject to non-penetrating (blunt impact, contusion-type injuries are commonly identified beneath the impact site (the coup and, in some instances, at the opposite pole (the contre-coup. This pattern of injury has long eluded satisfactory explanation and blunt head injury mechanisms in general remain poorly understood. There are only a small number of studies in the open literature investigating the head's response to short duration impacts, which can occur in collisions with light projectiles. As such, the head impact literature to date has focussed almost exclusively on impact scenarios which lead to a quasi-static pressure response in the brain. In order to investigate the response of the head to a wide range of impact durations, parametric numerical studies were performed on a highly bio-fidelic finite element model of the human head created from in vivo magnetic resonance imaging (MRI scan data with non-linear tissue material properties. We demonstrate that short duration head impacts can lead to potentially deleterious transients of positive and negative intra-cranial pressure over an order of magnitude larger than those observed in the quasi-static regime despite reduced impact force and energy. The onset of this phenomenon is shown to be effectively predicted by the ratio of impact duration to the period of oscillation of the first ovalling mode of the system. These findings point to dramatically different pressure distributions in the brain and hence different patterns of injury depending on projectile mass, and provide a potential explanation for dual coup/contre-coup injuries observed clinically.

  7. 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 ...

  8. 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.

  9. 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.

  10. 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.

  11. 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. PMID:26723849

  12. 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

  13. The sequential structure of brain activation predicts skill.

    Science.gov (United States)

    Anderson, John R; Bothell, Daniel; Fincham, Jon M; Moon, Jungaa

    2016-01-29

    In an fMRI study, participants were trained to play a complex video game. They were scanned early and then again after substantial practice. While better players showed greater activation in one region (right dorsal striatum) their relative skill was better diagnosed by considering the sequential structure of whole brain activation. Using a cognitive model that played this game, we extracted a characterization of the mental states that are involved in playing a game and the statistical structure of the transitions among these states. There was a strong correspondence between this measure of sequential structure and the skill of different players. Using multi-voxel pattern analysis, it was possible to recognize, with relatively high accuracy, the cognitive states participants were in during particular scans. We used the sequential structure of these activation-recognized states to predict the skill of individual players. These findings indicate that important features about information-processing strategies can be identified from a model-based analysis of the sequential structure of brain activation. PMID:26707716

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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…

  1. 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

  2. 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

  3. 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

  4. 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

  5. Impact of diabetes on cognitive function and brain structure.

    Science.gov (United States)

    Moheet, Amir; Mangia, Silvia; Seaquist, Elizabeth R

    2015-09-01

    Both type 1 and type 2 diabetes have been associated with reduced performance on multiple domains of cognitive function and with structural abnormalities in the brain. With an aging population and a growing epidemic of diabetes, central nervous system-related complications of diabetes are expected to rise and could have challenging future public health implications. In this review, we will discuss the brain structural and functional changes that have been associated with type 1 and type 2 diabetes. Diabetes duration and glycemic control may play important roles in the development of cognitive impairment in diabetes, but the exact underlying pathophysiological mechanisms causing these changes in cognition and structure are not well understood. Future research is needed to better understand the natural history and the underlying mechanisms, as well as to identify risk factors that predict who is at greatest risk of developing cognitive impairment. This information will lead to the development of new strategies to minimize the impact of diabetes on cognitive function. PMID:26132277

  6. 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

  7. Sub-cortical brain structure segmentation using F-CNN's

    OpenAIRE

    Shakeri, Mahsa; Tsogkas, Stavros; Ferrante, Enzo; Lippe, Sarah; Kadoury, Samuel; Paragios, Nikos; Kokkinos, Iasonas

    2016-01-01

    In this paper we propose a deep learning approach for segmenting sub-cortical structures of the human brain in Magnetic Resonance (MR) image data. We draw inspiration from a state-of-the-art Fully-Convolutional Neural Network (F-CNN) architecture for semantic segmentation of objects in natural images, and adapt it to our task. Unlike previous CNN-based methods that operate on image patches, our model is applied on a full blown 2D image, without any alignment or registration steps at testing t...

  8. 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.

  9. 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

  10. 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. PMID:22809542

  11. Multi-atlas segmentation of subcortical brain structures via the AutoSeg software pipeline

    Directory of Open Access Journals (Sweden)

    Jiahui Wang

    2014-02-01

    Full Text Available Automated segmenting and labeling of individual brain anatomical regions, in MRI are challenging, due to the issue of individual structural variability. Although atlas-based segmentation has shown its potential for both tissue and structure segmentation, due to the inherent natural variability as well as disease-related changes in MR appearance, a single atlas image is often inappropriate to represent the full population of datasets processed in a given neuroimaging study. As an alternative for the case of single atlas segmentation, the use of multiple atlases alongside label fusion techniques has been introduced using a set of individual “atlases” that encompasses the expected variability in the studied population. In our study, we proposed a multi-atlas segmentation scheme with a novel graph-based atlas selection technique. We first paired and co-registered all atlases and the subject MR scans. A directed graph with edge weights based on intensity and shape similarity between all MR scans is then computed. The set of neighboring templates is selected via clustering of the graph. Finally, weighted majority voting is employed to create the final segmentation over the selected atlases. This multi-atlas segmentation scheme is used to extend a single-atlas-based segmentation toolkit entitled AutoSeg, which is an open-source, extensible C++ based software pipeline employing BatchMake for its pipeline scripting, developed at the Neuro Image Research and Analysis Laboratories of the University of North Carolina at Chapel Hill. AutoSeg performs N4 intensity inhomogeneity correction, rigid registration to a common template space, automated brain tissue classification based skull-stripping, and the multi-atlas segmentation. The multi-atlas-based AutoSeg has been evaluated on subcortical structure segmentation with a testing dataset of 20 adult brain MRI scans and 15 atlas MRI scans. The AutoSeg achieved mean Dice coefficients of 81.73% for the

  12. 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

  13. Towards the "baby connectome": Mapping the structural connectivity of the newborn brain

    OpenAIRE

    Tymofiyeva, O; Hess, CP; Ziv, E; Tian, N; Bonifacio, SL; McQuillen, PS; Ferriero, DM; Barkovich, AJ; Xu, D.

    2012-01-01

    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 der...

  14. Computerized morphometric assessment of brain structure with MR imaging

    International Nuclear Information System (INIS)

    Limitation of imaging technique and measurement method are believed to underlie much of the variability across morphometric studies of the brain. To reduce variability, the authors have chosen three-dimensional MR gradient-echo imaging as the optimal imaging technique and developed a semiautomated mensuration system in conjunction with EKTRON Applied Imaging Inc with high accuracy and reliability. Images were acquired on a 1.O-T MR imaging system (Siemens, Magnetom) using coronal gradient-echo, three-dimensional (fast low-angle shot) sequence. The basic algorithmic philosophy for automatic extraction of anatomic structures was the definition of an exterior edge. The program is menu-driven and designed to run on SUN 3-160 series microcomputer. Accuracy of the system was tested with a simple geometric phantom, a complex human ventricular phantom, and a fresh postmortem brain. System accuracy was within 2% of the true volumes. System reliability was evaluated in three patient populations: 12 patients with Alzheimer disease, nine schizophrenics, and nine normal age-matched Alzheimer controls

  15. 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)

  16. Brain white matter structure and information processing speed in healthy older age.

    Science.gov (United States)

    Kuznetsova, Ksenia A; Maniega, Susana Muñoz; Ritchie, Stuart J; Cox, Simon R; Storkey, Amos J; Starr, John M; Wardlaw, Joanna M; Deary, Ian J; Bastin, Mark E

    2016-07-01

    Cognitive decline, especially the slowing of information processing speed, is associated with normal ageing. This decline may be due to brain cortico-cortical disconnection caused by age-related white matter deterioration. We present results from a large, narrow age range cohort of generally healthy, community-dwelling subjects in their seventies who also had their cognitive ability tested in youth (age 11 years). We investigate associations between older age brain white matter structure, several measures of information processing speed and childhood cognitive ability in 581 subjects. Analysis of diffusion tensor MRI data using Tract-based Spatial Statistics (TBSS) showed that all measures of information processing speed, as well as a general speed factor composed from these tests (g speed), were significantly associated with fractional anisotropy (FA) across the white matter skeleton rather than in specific tracts. Cognitive ability measured at age 11 years was not associated with older age white matter FA, except for the g speed-independent components of several individual processing speed tests. These results indicate that quicker and more efficient information processing requires global connectivity in older age, and that associations between white matter FA and information processing speed (both individual test scores and g speed), unlike some other aspects of later life brain structure, are generally not accounted for by cognitive ability measured in youth. PMID:26254904

  17. 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...

  18. 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

    . All voxels outside the mask with a nonzero probability of being a facial feature are set to 0. The algorithm was applied to 342 datasets that included two different T1-weighted pulse sequences and four different diagnoses (depressed, Alzheimer's, and elderly and young control groups). Visual......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...

  19. 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...

  20. Density perturbations due to the inhomogeneous discrete spatial structure of space-time

    International Nuclear Information System (INIS)

    For the case that space-time permits an inhomogeneous discrete spatial structure due to varying gravitational fields or a foam-like structure of space-time, it is demonstrated that thermodynamic reasoning implies that matter-density perturbations will arise in the early universe

  1. Somato-axodendritic release of oxytocin into the brain due to calcium amplification is essential for social memory.

    Science.gov (United States)

    Higashida, Haruhiro

    2016-07-01

    Oxytocin (OT) is released into the brain from the cell soma, axons, and dendrites of neurosecretory cells in the hypothalamus. Locally released OT can activate OT receptors, form inositol-1,4,5-trisphosphate and elevate intracellular free calcium (Ca(2+)) concentrations [(Ca(2+)) i ] in self and neighboring neurons in the hypothalamus, resulting in further OT release: i.e., autocrine or paracrine systems of OT-induced OT release. CD38-dependent cyclic ADP-ribose (cADPR) is also involved in this autoregulation by elevating [Ca(2+)] i via Ca(2+) mobilization through ryanodine receptors on intracellular Ca(2+) pools that are sensitive to both Ca(2+) and cADPR. In addition, it has recently been reported that heat stimulation and hyperthermia enhance [Ca(2+)] i increases by Ca(2+) influx, probably through TRPM2 cation channels, suggesting that cADPR and TRPM2 molecules act as Ca(2+) signal amplifiers. Thus, OT release is not simply due to depolarization-secretion coupling. Both of these molecules play critical roles not only during labor and milk ejection in reproductive females, but also during social behavior in daily life in both genders. This was clearly demonstrated in CD38 knockout mice in that social behavior was impaired by reduction of [Ca(2+)] i elevation and subsequent OT secretion. Evidence for the associations of CD38 with social behavior and psychiatric disorder is discussed, especially in subjects with autism spectrum disorder. PMID:26586001

  2. Postoperative Structural Brain Changes and Cognitive Dysfunction in Patients with Breast Cancer

    Science.gov (United States)

    Kawai, Masaaki; Kotozaki, Yuka; Nouchi, Rui; Tada, Hiroshi; Takeuchi, Hikaru; Ishida, Takanori; Taki, Yasuyuki; Kawashima, Ryuta; Ohuchi, Noriaki

    2015-01-01

    Objective The primary purpose of this study was to clarify the influence of the early response to surgery on brain structure and cognitive function in patients with breast cancer. It was hypothesized that the structure of the thalamus would change during the early response after surgery due to the effects of anesthesia and would represent one aspect of an intermediate phenotype of postoperative cognitive dysfunction (POCD). Methods We examined 32 postmenopausal females with breast cancer and 20 age-matched controls. We assessed their cognitive function (attention, memory, and executive function), and performed brain structural MRI 1.5 ± 0.5 days before and 5.6 ± 1.2 days after surgery. Results We found a significant interaction between regional grey matter volume (rGMV) in the thalamus (P < 0.05, familywise error (FWE), small volume correction (SVC)) and one attention domain subtest (P = 0.001, Bonferroni correction) after surgery in the patient group compared with the control group. Furthermore, the changes in attention were significantly associated with sevoflurane anesthetic dose (r2 = 0.247, β = ‒0.471, P = 0.032) and marginally associated with rGMV changes in the thalamus (P = 0.07, FWE, SVC) in the Pt group. Conclusion Our findings suggest that alterations in brain structure, particularly in the thalamus, may occur shortly after surgery and may be associated with attentional dysfunction. This early postoperative response to anesthesia may represent an intermediate phenotype of POCD. It was assumed that patients experiencing other risk factors of POCD, such as the severity of surgery, the occurrence of complications, and pre-existing cognitive impairments, would develop clinical POCD with broad and multiple types of cognitive dysfunction. PMID:26536672

  3. The Accompanying Changes in Brain Structure of a Remitted Depression Patient with the Bupropion Treatment.

    Science.gov (United States)

    Hou, Yi-Cheng; Lai, Chien-Han

    2015-12-31

    The impacts from the bupropion on the brain structures have seldom been mentioned in the literature. The bupropion is a kind of antidepressant with dual action in the norepinephrine and dopamine receptors. Here we have a case to share about the bupropion-related effects in the brain structure. PMID:26598593

  4. The Accompanying Changes in Brain Structure of a Remitted Depression Patient with the Bupropion Treatment

    OpenAIRE

    Hou, Yi-Cheng; Lai, Chien-Han

    2015-01-01

    The impacts from the bupropion on the brain structures have seldom been mentioned in the literature. The bupropion is a kind of antidepressant with dual action in the norepinephrine and dopamine receptors. Here we have a case to share about the bupropion-related effects in the brain structure.

  5. 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...

  6. 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.)

  7. 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.)

  8. 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

  9. Brain Basics

    Medline Plus

    Full Text Available ... 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 show that brain growth in children with autism ...

  10. 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

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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...

  16. The Structural Connectome of the Human Brain in Agenesis of the Corpus Callosum

    OpenAIRE

    Owen, Julia P.; Li, Yi-Ou; Ziv, Etay; Strominger, Zoe; Gold, Jacquelyn; Bukhpun, Polina; Wakahiro, Mari; Friedman, Eric J.; Sherr, Elliott H; Mukherjee, Pratik

    2012-01-01

    Adopting a network perspective, the structural connectome reveals the large-scale white matter connectivity of the human brain, yielding insights into cerebral organization otherwise inaccessible to researchers and clinicians. Connectomics has great potential for elucidating abnormal connectivity in congenital brain malformations, especially axonal pathfinding disorders. Agenesis of the corpus callosum (AgCC) is one of the most common brain malformations and can also be considered a prototypi...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. Advancing multiscale structural mapping of the brain through fluorescence imaging and analysis across length scales.

    Science.gov (United States)

    Hogstrom, L J; Guo, S M; Murugadoss, K; Bathe, M

    2016-02-01

    Brain function emerges from hierarchical neuronal structure that spans orders of magnitude in length scale, from the nanometre-scale organization of synaptic proteins to the macroscopic wiring of neuronal circuits. Because the synaptic electrochemical signal transmission that drives brain function ultimately relies on the organization of neuronal circuits, understanding brain function requires an understanding of the principles that determine hierarchical neuronal structure in living or intact organisms. Recent advances in fluorescence imaging now enable quantitative characterization of neuronal structure across length scales, ranging from single-molecule localization using super-resolution imaging to whole-brain imaging using light-sheet microscopy on cleared samples. These tools, together with correlative electron microscopy and magnetic resonance imaging at the nanoscopic and macroscopic scales, respectively, now facilitate our ability to probe brain structure across its full range of length scales with cellular and molecular specificity. As these imaging datasets become increasingly accessible to researchers, novel statistical and computational frameworks will play an increasing role in efforts to relate hierarchical brain structure to its function. In this perspective, we discuss several prominent experimental advances that are ushering in a new era of quantitative fluorescence-based imaging in neuroscience along with novel computational and statistical strategies that are helping to distil our understanding of complex brain structure. PMID:26855758

  2. Using Structural Equation Modeling to Assess Functional Connectivity in the Brain: Power and Sample Size Considerations

    Science.gov (United States)

    Sideridis, Georgios; Simos, Panagiotis; Papanicolaou, Andrew; Fletcher, Jack

    2014-01-01

    The present study assessed the impact of sample size on the power and fit of structural equation modeling applied to functional brain connectivity hypotheses. The data consisted of time-constrained minimum norm estimates of regional brain activity during performance of a reading task obtained with magnetoencephalography. Power analysis was first…

  3. 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

  4. 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

  5. MRI changes due to early-delayed conformal radiotherapy and postsurgical effects in patients with brain tumors

    International Nuclear Information System (INIS)

    Purpose: Discernment of radiotherapy (XRT) effects vs. tumor activity is difficult in brain tumor patients during the months after XRT when white matter hyperintensities sometimes emerge. We examined brain scans in XRT-treated vs. untreated patients for early-delayed post-XRT effects. Methods and Materials: Brain regions susceptible to XRT injury were examined on magnetic resonance imaging (MRI) for T2-weighted hyperintensities and atrophy in 37 adults with low-grade primary brain tumors (13 nonirradiated and 24 irradiated). Cases evidencing recurrence/growth over the study period were censored. Interactions with age, mood, fatigue, medications, tumor type and grade, extent of resection, and laterality of MRI changes were examined. Results: Hyperintensity and atrophy ratings over time for the treated and untreated groups were not significantly different. White matter atrophy increased unrelated to XRT. In all patients combined, white matter atrophy and hyperintensities were greater at all time points and more lateralized in surgically treated patients. Conclusions: Radiotherapy status was not related to changes in MRI ratings during the weeks/months after XRT. Findings contradict assumptions about radiographically evidenced early-delayed XRT effects. Increases in T2-weighted hyperintensities during the 1-6-month period postconformal radiotherapy for low-grade tumors are likely not related to early-delayed XRT effects

  6. 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

  7. Perceiving musical scale structures. A cross-cultural event-related brain potentials study.

    Science.gov (United States)

    Neuhaus, Christiane

    2003-11-01

    In this study, event-related brain potentials (ERPs) are used to investigate the processing of musical scale structures from a cross-cultural perspective. ERP reactions reveal that universal listening strategies per se are modified by culture. PMID:14681138

  8. 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 that...

  9. 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...

  10. Reproducibility of the Structural Brain Connectome Derived from Diffusion Tensor Imaging

    OpenAIRE

    Bonilha, Leonardo; Gleichgerrcht, Ezequiel; Fridriksson, Julius; Rorden, Chris; Breedlove, Jesse L.; Nesland, Travis; Paulus, Walter; Helms, Gunther; Focke, Niels K.

    2015-01-01

    Rationale 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. Methods Twen...

  11. The dynamics of cysteine proteinase activity in brain structures of irrigated rat descendants during ontogenetic development

    OpenAIRE

    Чорна, Валентина Іванівна; Лянна, Ольга Леонідівна

    2016-01-01

    The aim of the work was to investigate the kind of lysosomal cysteine cathepsin L activity dependency in brain structures of irradiated rat descendants during ontogenetic development. It was shown that fractional x-ray radiation (25 cGy) of the female rats induced different changes of cathepsin L activity levels and their redistribution in brain structures of female rats’ descendants during postnatal development with the advantages of nonsedimentational activity that had maximum at the 6th da...

  12. 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...

  13. 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 ...

  14. Born with an Ear for Dialects? Structural Plasticity in the Expert Phonetician Brain

    OpenAIRE

    Golestani, N.; Price, C. J.; Scott, S.K.

    2011-01-01

    Are experts born with particular predispositions, or are they made through experience? We examined brain structure in expert phoneticians, individuals who are highly trained to analyze and transcribe speech. We found a positive correlation between the size of left pars opercularis and years of phonetic transcription training experience, illustrating how learning may affect brain structure. Phoneticians were also more likely to have multiple or split left transverse gyri in the auditory cortex...

  15. 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...

  16. 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

    . 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...... the effects of correlated variables on the observed scores are modeled through multivariate analysis...... 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. The...

  17. Highlighting the structure-function relationship of the brain with the Ising model and graph theory.

    Science.gov (United States)

    Das, T K; Abeyasinghe, P M; Crone, J S; Sosnowski, A; Laureys, S; Owen, A M; Soddu, A

    2014-01-01

    With the advent of neuroimaging techniques, it becomes feasible to explore the structure-function relationships in the brain. When the brain is not involved in any cognitive task or stimulated by any external output, it preserves important activities which follow well-defined spatial distribution patterns. Understanding the self-organization of the brain from its anatomical structure, it has been recently suggested to model the observed functional pattern from the structure of white matter fiber bundles. Different models which study synchronization (e.g., the Kuramoto model) or global dynamics (e.g., the Ising model) have shown success in capturing fundamental properties of the brain. In particular, these models can explain the competition between modularity and specialization and the need for integration in the brain. Graphing the functional and structural brain organization supports the model and can also highlight the strategy used to process and organize large amount of information traveling between the different modules. How the flow of information can be prevented or partially destroyed in pathological states, like in severe brain injured patients with disorders of consciousness or by pharmacological induction like in anaesthesia, will also help us to better understand how global or integrated behavior can emerge from local and modular interactions. PMID:25276772

  18. Highlighting the Structure-Function Relationship of the Brain with the Ising Model and Graph Theory

    Directory of Open Access Journals (Sweden)

    T. K. Das

    2014-01-01

    Full Text Available With the advent of neuroimaging techniques, it becomes feasible to explore the structure-function relationships in the brain. When the brain is not involved in any cognitive task or stimulated by any external output, it preserves important activities which follow well-defined spatial distribution patterns. Understanding the self-organization of the brain from its anatomical structure, it has been recently suggested to model the observed functional pattern from the structure of white matter fiber bundles. Different models which study synchronization (e.g., the Kuramoto model or global dynamics (e.g., the Ising model have shown success in capturing fundamental properties of the brain. In particular, these models can explain the competition between modularity and specialization and the need for integration in the brain. Graphing the functional and structural brain organization supports the model and can also highlight the strategy used to process and organize large amount of information traveling between the different modules. How the flow of information can be prevented or partially destroyed in pathological states, like in severe brain injured patients with disorders of consciousness or by pharmacological induction like in anaesthesia, will also help us to better understand how global or integrated behavior can emerge from local and modular interactions.

  19. 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

  20. Spontaneous intracranial hemorrhage in children: report of a hemophilia patient who survived due to a brain cyst

    Science.gov (United States)

    Colleti Junior, José; Koga, Walter; de Carvalho, Werther Brunow

    2015-01-01

    We report the case of a 2-year-old child who survived an acute episode of severe spontaneous intracranial hemorrhage with clinical and radiological signs of intracranial hypertension and transtentorial herniation. The patient underwent emergency surgery to drain the hematoma, and a catheter was inserted to monitor intracranial pressure. In the initial computed tomography analysis performed prior to hematoma drainage, a brain cyst was evident contralateral to the hematoma, which, based on the analysis by the care team, possibly helped to avoid a worse outcome because the cyst accommodated the brain after the massive hemorrhage. After the investigation, the patient was determined to have previously undiagnosed hemophilia A. The patient underwent treatment in intensive care, which included the control of intracranial pressure, factor VIII replacement and discharge without signs of neurological impairment. PMID:26761482

  1. Potential Consequences of Essential Drug Shortages in Canada: Brain Abscess due to Nocardia farcinica Associated with Dapsone Prophylaxis for Pneumocystis jirovecii Pneumonia

    OpenAIRE

    Wuerz, Terry C; Bow, Eric J; Matthew D Seftel

    2013-01-01

    In 2012, Canadian pharmacies experienced a shortage of trimethoprim-sulfamethoxazole tablets. Drug shortages may result in unintended clinical consequences such as infection with pathogens against which the alternative medication is ineffective. This is highlighted in the present article, which describes a case of brain abscess due to Nocardia species that developed while receiving dapsone as an alternative for prophylaxis against Pneumocystis jirovecii pneumonia in a highly immune-suppressed...

  2. 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...

  3. Prediction of brain-computer interface aptitude from individual brain structure

    OpenAIRE

    Sebastian Halder; Balint Varkuti; Martin Bogdan; Ranganatha Sitaram

    2013-01-01

    Objective: Brain-computer interfaces (BCIs) provide a non-muscular communication channel for patients with impairments of the motor system. A significant number of BCI users is unable to obtain voluntary control of a BCI-system in proper time. This makes methods that can be used to determine the aptitude of a user necessary. Methods: We hypothesized that integrity and connectivity of involved white matter connections may serve as a predictor of individual BCI-performance. Therefore, we ana...

  4. 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.

  5. 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

  6. Internal Structure of Asteroids Having Surface Shedding due to Rotational Instability

    CERN Document Server

    Hirabayashi, Masatoshi; Scheeres, Daniel J

    2015-01-01

    Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to such surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-Sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this pa...

  7. Internal Structure of Asteroids Having Surface Shedding Due to Rotational Instability

    Science.gov (United States)

    Hirabayashi, Masatoshi; Sánchez, Diego Paul; Scheeres, Daniel J.

    2015-07-01

    Surface shedding of an asteroid is a failure mode where surface materials fly off due to strong centrifugal forces beyond the critical spin period, while the internal structure does not deform significantly. This paper proposes a possible structure of an asteroid interior that leads to surface shedding due to rapid rotation rates. A rubble pile asteroid is modeled as a spheroid composed of a surface shell and a concentric internal core, the entire assembly called the test body. The test body is assumed to be uniformly rotating around a constant rotation axis. We also assume that while the bulk density and the friction angle are constant, the cohesion of the surface shell is different from that of the internal core. First, developing an analytical model based on limit analysis, we provide the upper and lower bounds for the actual surface shedding condition. Second, we use a Soft-sphere Discrete Element Method (SSDEM) to study dynamical deformation of the test body due to a quasi-static spin-up. In this paper we show the consistency of both approaches. Additionally, the SSDEM simulations show that the initial failure always occurs locally and not globally. In addition, as the core becomes larger, the size of lofted components becomes smaller. These results imply that if there is a strong core in a progenitor body, surface shedding is the most likely failure mode.

  8. 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

  9. Brain structure links trait creativity to openness to experience

    OpenAIRE

    Li, Wenfu; Li, Xueting; Huang, Lijie; Kong, Xiangzhen; Yang, Wenjing; Wei, Dongtao; Li, Jingguang; Cheng, Hongsheng; Zhang, Qinglin; Qiu, Jiang; Liu, Jia

    2014-01-01

    Creativity is crucial to the progression of human civilization and has led to important scientific discoveries. Especially, individuals are more likely to have scientific discoveries if they possess certain personality traits of creativity (trait creativity), including imagination, curiosity, challenge and risk-taking. This study used voxel-based morphometry to identify the brain regions underlying individual differences in trait creativity, as measured by the Williams creativity aptitude tes...

  10. Etiology of structural brain asymmetry in schizophrenia, an alternative hypothesis

    OpenAIRE

    Bracha, HS

    1991-01-01

    During normal development of the fetal brain, the left hemisphere lags behind the right hemisphere in intrauterine growth, causing the left hemisphere to be smaller than the right hemisphere throughout the early and mid-prenatal period. By the end of the second trimester, the right hemisphere has achieved almost full-term size; thus second-trimester injuries affecting neurons, that is, anoxic, ischemic, toxic, or infectious insults that are systemic and bilateral, will affect the left hemisph...

  11. 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...

  12. 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...

  13. 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...

  14. 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

  15. 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

    2016-01-01

    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. PMID:26984298

  16. 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.

  17. Brain Stem Infarction Due to Basilar Artery Dissection in a Patient with Moyamoya Disease Four Years after Successful Bilateral Revascularization Surgeries.

    Science.gov (United States)

    Abe, Takatsugu; Fujimura, Miki; Mugikura, Shunji; Endo, Hidenori; Tominaga, Teiji

    2016-06-01

    Moyamoya disease (MMD) is a rare cerebrovascular disease with an unknown etiology and is characterized by intrinsic fragility in the intracranial vascular walls such as the affected internal elastic lamina and thinning medial layer. The association of MMD with intracranial arterial dissection is extremely rare, whereas that with basilar artery dissection (BAD) has not been reported previously. A 46-year-old woman developed brain stem infarction due to BAD 4 years after successful bilateral superficial temporal artery-middle cerebral artery anastomosis with indirect pial synangiosis for ischemic-onset MMD. She presented with sudden occipitalgia and subsequently developed transient dysarthria and mild hemiparesis. Although a transient ischemic attack was initially suspected, her condition deteriorated in a manner that was consistent with left hemiplegia with severe dysarthria. Magnetic resonance (MR) imaging revealed brain stem infarction, and MR angiography delineated a double-lumen sign in the basilar artery, indicating BAD. She was treated conservatively and brain stem infarction did not expand. One year after the onset of brain stem infarction, her activity of daily living is still dependent (modified Rankin Scale of 4), and there were no morphological changes associated with BAD or recurrent cerebrovascular events during the follow-up period. The association of MMD with BAD is extremely rare. While considering the common underlying pathology such as an affected internal elastic lamina and fragile medial layer, the occurrence of BAD in a patient with MMD in a stable hemodynamic state is apparently unique. PMID:27068774

  18. 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.

  19. 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.

  20. 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.

  1. Loads on structures inside reactor pressure vessels due to loca - decompression waves

    International Nuclear Information System (INIS)

    A theoretical model is described to calculate forces and moments onto core barrels, guide tubes of control rods, grid plates etc. inside the reactor pressure vessel due to decompression waves propagating with sonic velocity from the fracture during loss-of-coolant accidents in light water reactors. Simplicity of the model, short computer times and sufficient accuracy were the boundary conditions for the development. Therefore, no fluid dynamic coupling with the structure is considered. The main equations of the model are given and explained. The results of parametric studies as well as comparison to decompression wave experiments and calculations with coupling are presented. (orig.)

  2. 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.

  3. 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...

  4. Resolving anatomical and functional structure in human brain organization: identifying mesoscale organization in weighted network representations.

    Directory of Open Access Journals (Sweden)

    Christian Lohse

    2014-10-01

    Full Text Available Human brain anatomy and function display a combination of modular and hierarchical organization, suggesting the importance of both cohesive structures and variable resolutions in the facilitation of healthy cognitive processes. However, tools to simultaneously probe these features of brain architecture require further development. We propose and apply a set of methods to extract cohesive structures in network representations of brain connectivity using multi-resolution techniques. We employ a combination of soft thresholding, windowed thresholding, and resolution in community detection, that enable us to identify and isolate structures associated with different weights. One such mesoscale structure is bipartivity, which quantifies the extent to which the brain is divided into two partitions with high connectivity between partitions and low connectivity within partitions. A second, complementary mesoscale structure is modularity, which quantifies the extent to which the brain is divided into multiple communities with strong connectivity within each community and weak connectivity between communities. Our methods lead to multi-resolution curves of these network diagnostics over a range of spatial, geometric, and structural scales. For statistical comparison, we contrast our results with those obtained for several benchmark null models. Our work demonstrates that multi-resolution diagnostic curves capture complex organizational profiles in weighted graphs. We apply these methods to the identification of resolution-specific characteristics of healthy weighted graph architecture and altered connectivity profiles in psychiatric disease.

  5. 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.

  6. Brain Basics

    Medline Plus

    Full Text Available ... 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 ...

  7. Brain Basics

    Medline Plus

    Full Text Available ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as ... grow there are differences in brain development in children who develop bipolar disorder than children who do ...

  8. 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 ...

  9. 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...

  10. Brain structural and functional recovery following initiation of combination antiretroviral therapy

    OpenAIRE

    Becker, James T.; Cuesta, Pablo; Fabrizio, Melissa; Sudre, Gustavo; Vergis, Emanuel N.; Douaihy, Antoine; Bajo Breton, Ricardo; Schubert, Allie; Lopez, Oscar L.; Parkkonen, Lauri; Maestú, Fernando; Bagic, Anto

    2012-01-01

    NeuroAIDS persists in the era of combination antiretroviral therapies. We describe here the recovery of brain structure and function following 6 months of therapy in a treatment-naive patient presenting with HIV-associated dementia. The patient’s neuropsychological test performance improved and his total brain volume increased by more than 5 %. Neuronal functional connectivity measured by magnetoencephalography changed from a pattern identical to that observed in other HIV-infected individual...

  11. Testing Predictions From Personality Neuroscience: Brain Structure and the Big Five

    OpenAIRE

    DeYoung, Colin G.; Hirsh, Jacob B.; Shane, Matthew S.; Papademetris, Xenophon; Rajeevan, Nallakkandi; Gray, Jeremy R.

    2010-01-01

    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 brai...

  12. 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.

  13. 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) ...

  14. Spontaneous Functional Network Dynamics and Associated Structural Substrates in the Human Brain

    Directory of Open Access Journals (Sweden)

    Xuhong Liao

    2015-09-01

    Full Text Available Recent imaging connectomics studies have demonstrated that the spontaneous human brain functional networks derived from resting-state functional MRI (R-fMRI include many non-trivial topological properties, such as highly efficient small-world architecture and densely connected hub regions. However, very little is known about dynamic functional connectivity (D-FC patterns of spontaneous human brain networks during rest and about how these spontaneous brain dynamics are constrained by the underlying structural connectivity. Here, we combined sub-second multiband R-fMRI data with graph-theoretical approaches to comprehensively investigate the dynamic characteristics of the topological organization of human whole-brain functional networks, and then employed diffusion imaging data in the same participants to further explore the associated structural substrates. At the connection level, we found that human whole-brain D-FC patterns spontaneously fluctuated over time, while homotopic D-FC exhibited high connectivity strength and low temporal variability. At the network level, dynamic functional networks exhibited time-varying but evident small-world and assortativity architecture, with several regions (e.g., insula, sensorimotor cortex and medial prefrontal cortex emerging as functionally persistent hubs (i.e., highly connected regions while possessing large temporal variability in their degree centrality. Finally, the temporal characteristics (i.e., strength and variability of the connectional and nodal properties of the dynamic brain networks were significantly associated with their structural counterparts. Collectively, we demonstrate the economical, efficient and flexible characteristics of dynamic functional coordination in large-scale human brain networks during rest, and highlight their relationship with underlying structural connectivity, which deepens our understandings of spontaneous brain network dynamics in humans.

  15. 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.

  16. 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

  17. Primary Dystonia: Conceptualizing the Disorder Through a Structural Brain Imaging Lens

    OpenAIRE

    Ramdhani, Ritesh A.; Simonyan, Kristina

    2013-01-01

    Background Dystonia is a hyperkinetic movement disorder characterized by involuntary, repetitive twisting movements. The anatomical structures and pathways implicated in its pathogenesis and their relationships to the neurophysiological paradigms of abnormal surround inhibition, maladaptive plasticity, and impaired sensorimotor integration remain unclear. Objective We review the use of high-resolution structural brain imaging using voxel-based morphometry (VBM) and diffusion tensor imaging (D...

  18. 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.

  19. 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

  20. 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 the brain communicate and work with each other How changes in the brain ...

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. Long-term intensive training induced brain structural changes in world class gymnasts.

    Science.gov (United States)

    Huang, Ruiwang; Lu, Min; Song, Zheng; Wang, Jun

    2015-03-01

    Many previous studies suggested that both short-term and long-term motor training can modulate brain structures. However, little evidence exists for such brain anatomical changes in top-level gymnasts. Using diffusion-weighted and structural magnetic resonance images of the human brain, we applied voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) as well as FA-VBA (voxel-based analysis of fractional anisotropy, a VBM-style analysis) methods to quantitatively compare the brain structural differences between the world class gymnasts (WCG) and the non-athlete groups. In order to reduce the rate of false positive findings, we first determined that the clusters defined at a threshold of t > 2.3 and a cluster significance of p gymnasts' extraordinary ability to estimate the direction of their movements, their speed of execution, and their identification of their own and surrounding objects' locations. Our findings suggest that our method of constructing intersecting regions from multiple between-group comparison can considerably reduce the false positives, and our results provide new insights into the brain structure changes induced by long-term intensive gymnastic training. PMID:24297657

  8. Investigating dynamical information transfer in the brain following a TMS pulse: Insights from structural architecture.

    Science.gov (United States)

    Amico, Enrico; Van Mierlo, Pieter; Marinazzo, Daniele; Laureys, Steven

    2015-01-01

    Transcranial magnetic stimulation (TMS) has been used for more than 20 years to investigate connectivity and plasticity in the human cortex. By combining TMS with high-density electroencephalography (hd-EEG), one can stimulate any cortical area and measure the effects produced by this perturbation in the rest of the cerebral cortex. The purpose of this paper is to investigate changes of information flow in the brain after TMS from a functional and structural perspective, using multimodal modeling of source reconstructed TMS/hd-EEG recordings and DTI tractography. We prove how brain dynamics induced by TMS is constrained and driven by its structure, at different spatial and temporal scales, especially when considering cross-frequency interactions. These results shed light on the function-structure organization of the brain network at the global level, and on the huge variety of information contained in it. PMID:26737511

  9. 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.

  10. Variation in eligibility criteria from studies of radiculopathy due to a herniated disc and of neurogenic claudication due to lumbar spinal stenosis: a structured literature review

    OpenAIRE

    Genevay, Stéphane; Atlas, Steve J.; Katz, Jeffrey N.

    2010-01-01

    STUDY DESIGN: A structured literature review. SUMMARY OF THE BACKGROUND DATA: Widely recognized classification criteria for rheumatologic disorders have resulted in well-defined patient populations for clinical investigation. OBJECTIVE: We sought to determine whether similar criteria were needed for back pain disorders by examining variability in eligibility criteria in published studies. METHODS: Studies involving radiculopathy due to lumbar herniated disc (HD) and for neurogenic claudicatio...

  11. Structural performance evaluation on aging underground reinforced concrete structures. Part 1. Modeling of material degradation due to reinforcing steel corrosion

    International Nuclear Information System (INIS)

    This paper discusses effects of reinforcing steel corrosion on material properties of reinforced concrete and modeling of material degradation due to reinforcing steel corrosion used in a finite element method for structural analysis. First, we conducted a series of double-action tension tests on reinforced concrete specimens that were artificially corroded by stay current corrosion. We showed that the degradation ratio of yield strength of reinforcing steel agreeded well with maximum steel corrosion ratio and that tension softening of concrete became larger with the increase of corrosion degree. Second, based on these observations, reinforcement section area loss and initial tension strain due to reinforcement corrosion, a decrease in bond stress between reinforcement and concrete were employed for constructing the material model. To validate the devised modeling, the above -mentioned test results were numerically correlated. As a result, the analyzed load-strain relationships agreeded well with the experimental results under the condition of corrosion ratio 0-20%. Finally, as an application of experimental an analytical findings, we developed relationships between the parameters of modeling of material degradation and chloride induced deterioration progress as it widely accepted in maintenance practice for civil engineering reinforced concrete structures. (author)

  12. Nanoelectrospray high capacity ion trap multiple stage mass spectrometry for the structural analysis of human brain gangliosides

    International Nuclear Information System (INIS)

    Full text: A novel protocol based on electrospray ionization (ESI) multiple stage high capacity ion trap (HCT) mass spectrometry (MS) was developed for glycosphingolipidomic surveys. The method was optimized for detailed structural elucidation of human brain gangliosides and particularly applied to human hippocampus-associated structures. The multiple stage MS experiments allowed for a complete structural characterization of GM1 ganglioside species, which was achieved by elucidation of the oligosaccharide sequence, identification of the GM1 a structural isomer from the data upon sialic acid localization along the sugar backbone and determination of the d18:1/18:0 of fatty acid/sphingoid base composition of the ceramide moiety. The methodology developed here is of general practical applicability for glycolipids and represents a step forward in the implementation of the advanced and most modern MS methods in glycomics. Gangliosides are glycosphingolipids, which consist of a mono- to polysialylated oligosaccharide chain of variable length attached to a ceramide portion of different composition with respect to the type of sphingoid base and fatty acid residues. Among all body systems, the central nervous system (CNS) possesses the highest content of gangliosides and they are playing a particularly important biological role at this level. Specific changes in the ganglioside expression and type of the expressed structures were observed to occur during brain development, maturation, and aging, and due to diseases or neurodegeneration processes. Gangliosides represent, therefore, an important class of biomarkers, carriers of information upon various CNS processes and events. Though in the human brain, their expression was observed to have a regional and tissue development induced specificity, the differences in ganglioside structure, composition and quantity were not systematically investigated or rigorously determined so far. (authors)

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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

  1. How the brain attunes to sentence processing: Relating behavior, structure, and function

    Science.gov (United States)

    Fengler, Anja; Meyer, Lars; Friederici, Angela D.

    2016-01-01

    Unlike other aspects of language comprehension, the ability to process complex sentences develops rather late in life. Brain maturation as well as verbal working memory (vWM) expansion have been discussed as possible reasons. To determine the factors contributing to this functional development, we assessed three aspects in different age-groups (5–6 years, 7–8 years, and adults): first, functional brain activity during the processing of increasingly complex sentences; second, brain structure in language-related ROIs; and third, the behavioral comprehension performance on complex sentences and the performance on an independent vWM test. At the whole-brain level, brain functional data revealed a qualitatively similar neural network in children and adults including the left pars opercularis (PO), the left inferior parietal lobe together with the posterior superior temporal gyrus (IPL/pSTG), the supplementary motor area, and the cerebellum. While functional activation of the language-related ROIs PO and IPL/pSTG predicted sentence comprehension performance for all age-groups, only adults showed a functional selectivity in these brain regions with increased activation for more complex sentences. The attunement of both the PO and IPL/pSTG toward a functional selectivity for complex sentences is predicted by region-specific gray matter reduction while that of the IPL/pSTG is additionally predicted by vWM span. Thus, both structural brain maturation and vWM expansion provide the basis for the emergence of functional selectivity in language-related brain regions leading to more efficient sentence processing during development. PMID:26777477

  2. How the brain attunes to sentence processing: Relating behavior, structure, and function.

    Science.gov (United States)

    Fengler, Anja; Meyer, Lars; Friederici, Angela D

    2016-04-01

    Unlike other aspects of language comprehension, the ability to process complex sentences develops rather late in life. Brain maturation as well as verbal working memory (vWM) expansion have been discussed as possible reasons. To determine the factors contributing to this functional development, we assessed three aspects in different age-groups (5-6years, 7-8years, and adults): first, functional brain activity during the processing of increasingly complex sentences; second, brain structure in language-related ROIs; and third, the behavioral comprehension performance on complex sentences and the performance on an independent vWM test. At the whole-brain level, brain functional data revealed a qualitatively similar neural network in children and adults including the left pars opercularis (PO), the left inferior parietal lobe together with the posterior superior temporal gyrus (IPL/pSTG), the supplementary motor area, and the cerebellum. While functional activation of the language-related ROIs PO and IPL/pSTG predicted sentence comprehension performance for all age-groups, only adults showed a functional selectivity in these brain regions with increased activation for more complex sentences. The attunement of both the PO and IPL/pSTG toward a functional selectivity for complex sentences is predicted by region-specific gray matter reduction while that of the IPL/pSTG is additionally predicted by vWM span. Thus, both structural brain maturation and vWM expansion provide the basis for the emergence of functional selectivity in language-related brain regions leading to more efficient sentence processing during development. PMID:26777477

  3. 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

  4. Experimental analysis of the structure-borne tyre/road noise due to road discontinuities

    Science.gov (United States)

    Kindt, P.; Berckmans, D.; De Coninck, F.; Sas, P.; Desmet, W.

    2009-11-01

    Tyre/road noise has become the major source of traffic noise in urban regions. Although tyre/road noise has been studied for decades, little can be found in the literature about the noise resulting from crossing road discontinuities such as expansion joints, railway crossings, and potholes. Both vehicle interior and exterior noise can reach significant peak levels as a result of crossing such a pavement discontinuity. This paper presents an experimental analysis of the generating phenomena of structure borne tyre/road noise due to a road discontinuity. Both exterior and interior tyre/road noise are considered. The influence of driving speed, cleat dimension, inflation pressure, tyre temperature and preload onto the noise generating phenomena is investigated. A novel test setup was designed and built at the K.U. Leuven Noise and Vibration Engineering Laboratory in order to measure the structural and acoustic response of a tyre rolling over a cleat. The vehicle interior noise is analysed by means of a test circuit cleat test.

  5. 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.

  6. 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...

  7. Modular structure of brain functional networks: breaking the resolution limit by Surprise

    Science.gov (United States)

    Nicolini, Carlo; Bifone, Angelo

    2016-01-01

    The modular organization of brain networks has been widely investigated using graph theoretical approaches. Recently, it has been demonstrated that graph partitioning methods based on the maximization of global fitness functions, like Newman’s Modularity, suffer from a resolution limit, as they fail to detect modules that are smaller than a scale determined by the size of the entire network. Here we explore the effects of this limitation on the study of brain connectivity networks. We demonstrate that the resolution limit prevents detection of important details of the brain modular structure, thus hampering the ability to appreciate differences between networks and to assess the topological roles of nodes. We show that Surprise, a recently proposed fitness function based on probability theory, does not suffer from these limitations. Surprise maximization in brain co-activation and functional connectivity resting state networks reveals the presence of a rich structure of heterogeneously distributed modules, and differences in networks’ partitions that are undetectable by resolution-limited methods. Moreover, Surprise leads to a more accurate identification of the network’s connector hubs, the elements that integrate the brain modules into a cohesive structure.

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. Brain structure links trait creativity to openness to experience.

    Science.gov (United States)

    Li, Wenfu; Li, Xueting; Huang, Lijie; Kong, Xiangzhen; Yang, Wenjing; Wei, Dongtao; Li, Jingguang; Cheng, Hongsheng; Zhang, Qinglin; Qiu, Jiang; Liu, Jia

    2015-02-01

    Creativity is crucial to the progression of human civilization and has led to important scientific discoveries. Especially, individuals are more likely to have scientific discoveries if they possess certain personality traits of creativity (trait creativity), including imagination, curiosity, challenge and risk-taking. This study used voxel-based morphometry to identify the brain regions underlying individual differences in trait creativity, as measured by the Williams creativity aptitude test, in a large sample (n = 246). We found that creative individuals had higher gray matter volume in the right posterior middle temporal gyrus (pMTG), which might be related to semantic processing during novelty seeking (e.g. novel association, conceptual integration and metaphor understanding). More importantly, although basic personality factors such as openness to experience, extroversion, conscientiousness and agreeableness (as measured by the NEO Personality Inventory) all contributed to trait creativity, only openness to experience mediated the association between the right pMTG volume and trait creativity. Taken together, our results suggest that the basic personality trait of openness might play an important role in shaping an individual's trait creativity. PMID:24603022

  15. Brain Structure in Young and Old East Asians and Westerners: Comparisons of Structural Volume and Cortical Thickness

    Science.gov (United States)

    Chee, Michael Wei Liang; Zheng, Hui; Goh, Joshua Oon Soo; Park, Denise; Sutton, Bradley P.

    2011-01-01

    There is an emergent literature suggesting that East Asians and Westerners differ in cognitive processes because of cultural biases to process information holistically (East Asians) or analytically (Westerners). To evaluate the possibility that such differences are accompanied by differences in brain structure, we conducted a large comparative…

  16. MRI-detectable changes in mouse brain structure induced by voluntary exercise.

    Science.gov (United States)

    Cahill, Lindsay S; Steadman, Patrick E; Jones, Carly E; Laliberté, Christine L; Dazai, Jun; Lerch, Jason P; Stefanovic, Bojana; Sled, John G

    2015-06-01

    Physical exercise, besides improving cognitive and mental health, is known to cause structural changes in the brain. Understanding the structural changes that occur with exercise as well as the neuroanatomical correlates of a predisposition for exercise is important for understanding human health. This study used high-resolution 3D MR imaging, in combination with deformation-based morphometry, to investigate the macroscopic changes in brain structure that occur in healthy adult mice following four weeks of voluntary exercise. We found that exercise induced changes in multiple brain structures that are involved in motor function and learning and memory including the hippocampus, dentate gyrus, stratum granulosum of the dentate gyrus, cingulate cortex, olivary complex, inferior cerebellar peduncle and regions of the cerebellum. In addition, a number of brain structures, including the hippocampus, striatum and pons, when measured on MRI prior to the start of exercise were highly predictive of subsequent exercise activity. Exercise tended to normalize these pre-existing differences between mice. PMID:25800209

  17. 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

  18. 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.

  19. Topological correlations of structural and functional networks in patients with traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Karen Caeyenberghs

    2013-11-01

    Full Text Available Despite an increasing amount of specific correlation studies between structural and functional connectivity, there is still a need for combined studies, especially in pathological conditions. Impairments of brain white matter and diffuse axonal injuries are commonly suspected to be responsible for the disconnection hypothesis in traumatic brain injury (TBI patients. Moreover, our previous research on TBI patients shows a strong relationship between abnormalities in topological organization of brain networks and behavioral deficits. In this study, we combined task-related functional connectivity (using event-related fMRI with structural connectivity (derived from fiber tractography using diffusion MRI data estimates in the same participants (17 adults with TBI and 16 controls, allowing for direct comparison between graph metrics of the different imaging modalities. Connectivity matrices were computed covering the switching motor network, which includes the basal ganglia, anterior cingulate cortex/supplementary motor area, and anterior insula/inferior frontal gyrus. The edges constituting this network consisted of the partial correlations between the fMRI time series from each node of the switching motor network. The interregional anatomical connections between the switching-related areas were determined using the fiber tractography results. We found that graph metrics and hubs obtained showed no agreement in both groups. The topological properties of brain functional networks could not be solely accounted for the properties of the underlying structural networks. However, combining complementary information from both different imaging modalities could improve accuracy in prediction of switching performance. Direct comparison between functional task-related and anatomical structural connectivity, presented here for the first time in TBI patients, links two powerful approaches to map the patterns of brain connectivity that may underlie behavioral

  20. Brain mapping

    OpenAIRE

    Blaž Koritnik

    2004-01-01

    Cartography of the brain ("brain mapping") aims to represent the complexities of the working brain in an understandable and usable way. There are four crucial steps in brain mapping: (1) acquiring data about brain structure and function, (2) transformation of data into a common reference, (3) visualization and interpretation of results, and (4) databasing and archiving. Electrophysiological and functional imaging methods provide information about function of the human brain. A prere...

  1. Brain Basics

    Medline Plus

    Full Text Available ... and the environment affect the brain The basic structure of the brain How different parts of the ... for the cell to work properly including small structures called cell organelles. Dendrites branch off from the ...

  2. Structural brain MRI studies in eye diseases: are they clinically relevant? A review of current findings.

    Science.gov (United States)

    Prins, Doety; Hanekamp, Sandra; Cornelissen, Frans W

    2016-03-01

    Many eye diseases reduce visual acuity or are associated with visual field defects. Because of the well-defined retinotopic organization of the connections of the visual pathways, this may affect specific parts of the visual pathways and cortex, as a result of either deprivation or transsynaptic degeneration. For this reason, over the past several years, numerous structural magnetic resonance imaging (MRI) studies have examined the association of eye diseases with pathway and brain changes. Here, we review structural MRI studies performed in human patients with the eye diseases albinism, amblyopia, hereditary retinal dystrophies, age-related macular degeneration (AMD) and glaucoma. We focus on two main questions. First, what have these studies revealed? Second, what is the potential clinical relevance of their findings? We find that all the aforementioned eye diseases are indeed associated with structural changes in the visual pathways and brain. As such changes have been described in very different eye diseases, in our view the most parsimonious explanation is that these are caused by the loss of visual input and the subsequent deprivation of the visual pathways and brain regions, rather than by transsynaptic degeneration. Moreover, and of clinical relevance, for some of the diseases - in particular glaucoma and AMD - present results are compatible with the view that the eye disease is part of a more general neurological or neurodegenerative disorder that also affects the brain. Finally, establishing structural changes of the visual pathways has been relevant in the context of new therapeutic strategies to restore retinal function: it implies that restoring retinal function may not suffice to also effectively restore vision. Future structural MRI studies can contribute to (i) further establish relationships between ocular and neurological neurodegenerative disorders, (ii) investigate whether brain degeneration in eye diseases is reversible, (iii) evaluate the use

  3. Tissue structure and inflammatory processes shape viscoelastic properties of the mouse brain.

    Science.gov (United States)

    Millward, Jason M; Guo, Jing; Berndt, Dominique; Braun, Jürgen; Sack, Ingolf; Infante-Duarte, Carmen

    2015-07-01

    Magnetic resonance elastography (MRE) is an imaging method that reveals the mechanical properties of tissue, modelled as a combination of " viscosity" and " elasticity" . We recently showed reduced brain viscoelasticity in multiple sclerosis (MS) patients compared with healthy controls, and in the relapsing-remitting disease model experimental autoimmune encephalomyelitis (EAE). However, the mechanisms by which these intrinsic tissue properties become altered remain unclear. This study investigates whether distinct regions in the mouse brain differ in their native viscoelastic properties, and how these properties are affected during chronic EAE in C57Bl/6 mice and in mice lacking the cytokine interferon-gamma. IFN-γ(-/-) mice exhibit a more severe EAE phenotype, with amplified inflammation in the cerebellum and brain stem. Brain scans were performed in the sagittal plane using a 7 T animal MRI scanner, and the anterior (cerebral) and posterior (cerebellar) regions analyzed separately. MRE investigations were accompanied by contrast-enhanced MRI scans, and by histopathology and gene expression analysis ex vivo. Compared with the cerebrum, the cerebellum in healthy mice has a lower viscoelasticity, i.e. it is intrinsically " softer" . This was seen both in the wild-type mice and the IFNγ(-/-) mice. During chronic EAE, C57Bl/6 mice did not show altered brain viscoelasticity. However, as expected, the IFNγ(-/-) mice showed a more severe EAE phenotype, and these mice did show altered brain elasticity during the course of disease. The magnitude of the elasticity reduction correlated with F4/80 gene expression, a marker for macrophages/microglia in inflamed central nervous system tissue. Together these results demonstrate that MRE is sensitive enough to discriminate between viscoelastic properties in distinct anatomical structures in the mouse brain, and to confirm a further relationship between cellular inflammation and mechanical alterations of the brain. This

  4. 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…

  5. 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…

  6. 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

  7. 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.

  8. 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 (

  9. 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...

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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 ...

  15. Assessing dynamical correlations between functional and structural brain connectivity

    OpenAIRE

    Liegeois, Raphaël; Ziegler, Erik; Phillips, Christophe; Gomez, Francisco; Soddu, Andrea; Laureys, Steven; Sepulchre, Rodolphe

    2014-01-01

    The link between resting­‐state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC) has been repeatedly investigated recently. Meanwhile, the importance of considering the dynamics of neuronal processes has also been highlighted. In this work we show how the classical static (i.e. considered as constant) relationship between SC and FC could be enriched when the FC dynamics are taken into account. We use a sliding window...

  16. A structural difference based image clutter metric with brain cognitive model constraints

    Science.gov (United States)

    Xu, Dejiang; Shi, Zelin; Luo, Haibo

    2013-03-01

    Previous clutter metrics have less than the desired accuracy in predicting targeting performance, in this paper, a structural difference based image clutter metric is proposed based on the given definition of image clutter metric. According to the sensitivity of human visual perception to image structural information, a structural similarity measure between the target and clutter images is firstly established. Previous clutter metrics not considering brain cognitive characteristics, we define an information content weight measure by introducing the widely accepted brain cognitive information extracting model in the field of image quality assessment (IQA), and then, pool the structural similarity measure to be a clutter metric, which can be entitled BSD metric. Comparative field tests show that BSD metric makes a more significant improvement than previously proposed metrics in predicting target acquisition performance including detection probability and search time.

  17. 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...

  18. Activation of structural materials due to recoil protons in light water reactor

    International Nuclear Information System (INIS)

    The long-lived radioactivities of structural materials induced by recoil protons in BWR were estimated for land disposal of low level waste after reactor decommissioning. Reaction products of interest are 53Mn, 91Nb, 94Nb, 97Tc, 125Sb, 173Lu and 174Lu. A method of calculating the proton spectrum in materials was presented. The program PEGASUS-P was developed by modifying the PEGASUS, a preequilibrium and multistep evaporation theory code, to calculate proton reaction cross sections. The proton-induced activities in stainless steel, Inconel and Zircaloy-2 were calculated under typical irradiation conditions in an operating BWR. It was shown that even the most dominant activity due to 91Nb from Zircaloy-2 did not exceed 1/1,000 of that of a typical neutron induced activity of 63Ni for cooling up to 1,000 yr after the irradiation of 40 yr. The results are believed to hold for the case of PWR as well. (author)

  19. 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.)

  20. 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.

  1. Human Development XI: The Structure of the Cerebral Cortex. Are There Really Modules in the Brain?

    OpenAIRE

    Tyge Dahl Hermansen; Søren Ventegodt; Isack Kandel

    2007-01-01

    The structure of human consciousness is thought to be closely connected to the structure of cerebral cortex. One of the most appreciated concepts in this regard is the Szanthagothei model of a modular building of neo-cortex. The modules are believed to organize brain activity pretty much like a computer. We looked at examples in the literature and argue that there is no significant evidence that supports Szanthagothei's model. We discuss the use of the limited genetic information, the cortico...

  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. 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.

  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. 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.

  6. 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

  7. 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.

  8. Structural Brain Network Characteristics Can Differentiate CIS from Early RRMS.

    Science.gov (United States)

    Muthuraman, Muthuraman; Fleischer, Vinzenz; Kolber, Pierre; Luessi, Felix; Zipp, Frauke; Groppa, Sergiu

    2016-01-01

    Focal demyelinated lesions, diffuse white matter (WM) damage, and gray 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, 33 with RRMS, and 40 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 dissemination-in-time criteria for

  9. Brain Basics

    Medline Plus

    Full Text Available ... 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 show that brain growth in children with autism appears to peak early. And as ...

  10. 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 ...

  11. Dynamic structural analysis concerning integrity assessment of a reinforced concrete ceiling due to impact loads

    International Nuclear Information System (INIS)

    In the framework of the activities concerning the safety of nuclear power plants (NPP) in Middle- and East Europe among others the behaviour of the reactor cavity bottom ceiling of a NPP of type WWER-1000 impinged by impact loads due to the postulated failure of the lower head of the reactor pressure vessel (RPV-LH) caused by an assumed core melt accident has been investigated. For the investigations of the structure dynamical behaviour of the reactor cavity ceiling the AUTODYN-Code was used. This code is using an explicit solver and is suitable particularly for the simulation of impact problems. For the investigations on the load bearing capacity of the cavity ceiling an axisymmetric Finite Element (FE) model of both the RPV-LH made of steel and the reactor cavity ceiling with detailed consideration of the reinforcement in the concrete was generated. The effects of the rebars were simulated by shell elements with adequate cross-sections based on the number of rebars. To represent the load and temperature dependent deformation of the heated RPV-LH during the impact phase the FE-model has steel layers of different temperature dependent material properties representing the assumed temperature distribution over the wall thickness at postulated failure. The assumed molten core material located above the inner surface of the RPV-LH is taken into account by adjusting the density of the lower head. In the dynamic calculations the internal pressure conditions at the time of failure and consequently the impact velocity were varied. The calculations show the damage of the concrete and the strains in the reinforcement were assessed by adequate failure criteria. (authors)

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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 ...

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

    Directory of Open Access Journals (Sweden)

    Jonathan List

    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.

  3. The influence of preterm birth on structural alterations of the vision-deprived brain.

    Science.gov (United States)

    Wan, Catherine Y; Wood, Amanda G; Chen, Jian; Wilson, Sarah J; Reutens, David C

    2013-04-01

    Differences in brain structures between blind and sighted individuals have not been widely investigated. Furthermore, existing studies have included individuals who were blinded by retinopathy of prematurity, a condition that is associated with premature birth. Recent pediatric research has reported structural differences in individuals who were born prematurely, suggesting that some of the structural abnormalities previously observed in blind individuals may be related to prematurity rather than being specific to blindness. In the present study, we used voxel-based morphometry to investigate gray and white matter differences between 24 blind and 16 sighted individuals. Of the blind individuals, six were born prematurely and 18 at term. Compared to those born at term, blind individuals born preterm showed differences in gray, but not white, matter volumes in various brain regions. When the preterm individuals were excluded from analysis, there were significant differences between blind and sighted individuals. Full-term blind individuals showed regional gray matter decreases in the cuneus, lingual gyrus, middle occipital gyrus, precuneus, inferior and superior parietal lobules, and the thalamus, and gray matter increases in the globus pallidus. They also showed regional white matter decreases in the cuneus, lingual gyrus, and the posterior cingulate. These differences were observed in blind individuals irrespective of blindness onset age, providing evidence for structural alterations in the mature brain. Our findings highlight the importance of considering the potential impact of premature birth on neurodevelopmental outcomes in studies of blind individuals. PMID:22591801

  4. 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.

  5. 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.

  6. 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

  7. Brain mapping

    Directory of Open Access Journals (Sweden)

    Blaž Koritnik

    2004-08-01

    Full Text Available Cartography of the brain ("brain mapping" aims to represent the complexities of the working brain in an understandable and usable way. There are four crucial steps in brain mapping: (1 acquiring data about brain structure and function, (2 transformation of data into a common reference, (3 visualization and interpretation of results, and (4 databasing and archiving. Electrophysiological and functional imaging methods provide information about function of the human brain. A prerequisite for multisubject, multidimensional and multimodal mapping is transformation of individual images to match a standard brain template. To produce brain maps, color, contours, and other visual cues are used to differentiate metabolic rates, electrical field potentials, receptor densities, and other attributes of structure or function. Databases are used to organize and archive data records. By relating the maps to cognitive functions and psychological models, brain mapping offers a prerequisite for the understanding of organizational principles of the human brain.

  8. 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...

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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...

  15. Interactive 3D visualization of structural changes in the brain of a person with corticobasal syndrome

    OpenAIRE

    Claudia Hänel; Peter Pieperhoff; Katrin Amunts

    2014-01-01

    The visualization of the progression of brain tissue loss in neurodegenerative diseases like corticobasal syndrome (CBS) can provide not only information about the localization and distribution of the volume loss, but also helps to understand the course and the causes of this neurodegenerative disorder. The visualization of such medical imaging data is often based on 2D sections, because they show both internal and external structures in one image. Spatial information, however, is lost. 3D vi...

  16. 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...

  17. 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...

  18. 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...

  19. Duration of Early Adversity and Structural Brain Development in Post-Institutionalized Adolescents

    OpenAIRE

    Hodel, Amanda S.; Hunt, Ruskin H.; Cowell, Raquel A.; Van Den Heuvel, Sara E.; Gunnar, Megan R.; Thomas, Kathleen M.

    2014-01-01

    For children reared in institutions for orphaned or abandoned children, multiple aspects of the early environment deviate from species-typical experiences, which may lead to alterations in neurobehavioral development. Although the effects of early deprivation and early life stress have been studied extensively in animal models, less is known about implications for human brain development. This structural neuroimaging study examined the long-term neural correlates of early adverse rearing envi...

  20. 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.

  1. 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.

  2. 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.

  3. The effect of beta-turn structure on the permeation of peptides across monolayers of bovine brain microvessel endothelial cells

    DEFF Research Database (Denmark)

    Sorensen, M; Steenberg, B; Knipp, G T; Wang, W; Steffansen, B; Frokjaer, S; Borchardt, R T

    1997-01-01

    PURPOSE: To investigate the effects of the beta-turn structure of a peptide on its permeation via the paracellular and transcellular routes across cultured bovine brain microvessel endothelial cell (BBMEC) monolayers, an in vitro model of the blood-brain barrier (BBB). METHODS: The effective perm...

  4. 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.

  5. 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 ...

  6. 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, ...

  7. 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 ...

  8. 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)

  9. Frontoparietal Connectivity and Hierarchical Structure of the Brain's Functional Network during Sleep.

    Science.gov (United States)

    Spoormaker, Victor I; Gleiser, Pablo M; Czisch, Michael

    2012-01-01

    Frontal and parietal regions are associated with some of the most complex cognitive functions, and several frontoparietal resting-state networks can be observed in wakefulness. We used functional magnetic resonance imaging data acquired in polysomnographically validated wakefulness, light sleep, and slow-wave sleep to examine the hierarchical structure of a low-frequency functional brain network, and to examine whether frontoparietal connectivity would disintegrate in sleep. Whole-brain analyses with hierarchical cluster analysis on predefined atlases were performed, as well as regression of inferior parietal lobules (IPL) seeds against all voxels in the brain, and an evaluation of the integrity of voxel time-courses in subcortical regions-of-interest. We observed that frontoparietal functional connectivity disintegrated in sleep stage 1 and was absent in deeper sleep stages. Slow-wave sleep was characterized by strong hierarchical clustering of local submodules. Frontoparietal connectivity between IPL and superior medial and right frontal gyrus was lower in sleep stages than in wakefulness. Moreover, thalamus voxels showed maintained integrity in sleep stage 1, making intrathalamic desynchronization an unlikely source of reduced thalamocortical connectivity in this sleep stage. Our data suggest a transition from a globally integrated functional brain network in wakefulness to a disintegrated network consisting of local submodules in slow-wave sleep, in which frontoparietal inter-modular nodes may play a role, possibly in combination with the thalamus. PMID:22629253

  10. 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

    2010-05-13

    Scale-free dynamics, with a power spectrum following P proportional to f(-beta), 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 beta 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

  11. 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.)

  12. 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.)

  13. Rats with minimal hepatic encephalopathy due to portacaval shunt show differential increase of translocator protein (18 kDa) binding in different brain areas, which is not affected by chronic MAP-kinase p38 inhibition

    OpenAIRE

    Agusti, Ana; Dziedzic, Jennifer L.; Hernandez-Rabaza, Vicente; Guilarte, Tomas R.; Felipo, Vicente

    2013-01-01

    Neuroinflammation plays a main role in neurological deficits in rats with minimal hepatic encephalopathy (MHE) due to portacaval shunt (PCS). Treating PCS rats with SB239063, an inhibitor of MAP-kinase-p38, reduces microglial activation and brain inflammatory markers and restores cognitive and motor function. The translocator protein-(18-kDa) (TSPO) is considered a biomarker of neuro-inflammation. TSPO is increased in brain of PCS rats and of cirrhotic patients that died in hepatic coma. Rats...

  14. Are there novel resonances in nanoplasmonic structures due to nonlocal response?

    DEFF Research Database (Denmark)

    Wubs, Martijn; Raza, Søren; Toscano, Giuseppe;

    2012-01-01

    nanostructures that have no counterpart in the local-response Drude model. Even though there are no additional resonances in the visible due to nonlocal response, plasmonic field enhancements are affected by nonlocal response. We present both analytical results for simple geometries and our numerical...

  15. Frequency response experiments for a fluid and structure interaction system due to thermal stripping in sodium

    International Nuclear Information System (INIS)

    thermal striping phenomena induced by the alternate flows of cold and hot sodium impinging against a horizontal test piece surface were investigated. The temperatures of sodium and structure material were measured simultaneously using thermocouples located various positions. From the present experiments, the following results have been obtained. (1) The alternate flows of cold and hot sodium with the frequency from 0.01 Hz to 0.2 Hz and the temperature difference of 240degC were composed using the opening and closing operations of a cold and a hot sodium valve alternately. (2) The change and fluctuation of temperature amplitude in sodium decreases with decreasing of frequency component. (3) Amplitude component of temperature vibration decreased extremely in the structure material inside of the test piece than sodium. (4) Amplitude component of temperature vibration in the structure material increases in inverse proportion to decreasing of frequency component. (5) Amplitude component change of temperature vibration in the structure material decreases with decreasing of frequency component. (6) Fine fluctuations of temperature vibration in the structure material increases with increasing of frequency component, but it was limited near the surface of material. (7) Fine fluctuations of temperature vibration in the structure material decreases with decreasing of frequency component, but it was penetrated into the deep inner part of the material. (author)

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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.)

  6. 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.)

  7. Low energy dislocation structures due to unidirectional deformation at low temperatures

    DEFF Research Database (Denmark)

    Hansen, Niels; Kuhlmann-Wilsdorf, D.

    1986-01-01

    are considered in this paper: (i) the sum of the energy stored in the dislocation line energy and the longer-range stresses is significantly smaller than some recently reported experimental values; (ii) subdivision of cells is discussed on the basis of observations in rolled aluminum showing a...... “hierarchical” cell structure; (iii) suggestions are made to account for microband formation on the basis of energy minimization. Finally, the relationship between surface markings and the underlying dislocation structure is discussed and related to slip processes taking place during uniaxial deformation....

  8. THE CASE OF FOCAL EPILEPSY OF CHILDHOOD WITH STRUCTURAL BRAIN CHANGES AND BENIGN EPILEPTIFORM DISCHARGES ON EEG (FECSBC-BEDC)

    OpenAIRE

    I. A. Sadekov; Petrenko, L. V.; I. V. Sadekova; O. I. Tishkovets

    2015-01-01

    The authors described a case of focal epilepsy of childhood with structural brain changes and benign epileptiform discharges on EEG (FECSBC-BEDC). Correct syndromological diagnostics helped to clarify the clinical dynamics, prognosis and improve the therapy.

  9. 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

    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...

  10. Quantification of changes in modal parameters due to the presence of passive people on a slender structure

    Science.gov (United States)

    Busca, G.; Cappellini, A.; Manzoni, S.; Tarabini, M.; Vanali, M.

    2014-10-01

    This work proposes a method to predict changes in modal parameters of a generic structure due to the presence of passive people. The method requires to accurately know the modal model of the empty structure, i.e. natural frequencies, damping ratios and mode shapes. No restriction on the number of degrees of freedom of the structure is required. Each passive subject on the structure is modelled through his apparent mass and is introduced locally on the empty structure to obtain a model of the joint human-structure system. To include the apparent mass of the subjects in the model both measurements and models available in literature were used. The effect of using different models of the apparent mass was investigated and the effect of using apparent masses obtained with different levels of vibration was analysed. The proposed model was validated by means of experimental tests carried out on a lightly damped staircase. The empty structure was first tested to obtain its modal model in order to apply the proposed approach. After performing several tests with passive people standing on the structure, the experimental results showed small changes of natural frequencies (increase or decrease) and a high increase of damping ratios due to people's presence. Thus, the proposed approach was used to predict the above-mentioned changes. The measured and predicted frequency response functions, natural frequencies and damping ratios were compared. In all the cases taken into consideration, the predicted results fitted with the experimental evidence.

  11. Changes in the Modal Structure of Indoor Aerosol Due to Simulated Indoor Activities

    Czech Academy of Sciences Publication Activity Database

    Glytsos, T.; Ondráček, Jakub; Smolík, Jiří; Lazaridis, M.

    Helsinki : -, 2010, P1F42. ISBN N. [International Aerosol Conference IAC 2010. Helsinki (FI), 29.08.2010-03.09.2010] Institutional research plan: CEZ:AV0Z40720504 Keywords : indoor aerosol * modal structure Subject RIV: CF - Physical ; Theoretical Chemistry www.iac2010.fi

  12. 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

    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...

  13. Response of the residental building structure on load technical seismicity due to mining activities

    Czech Academy of Sciences Publication Activity Database

    Salajka, V.; Kaláb, Zdeněk; Kala, J.; Hradil, P.

    2009-01-01

    Roč. 38, č. 38 (2009), s. 218-226. ISSN 2070-3740 Grant ostatní: GA ČR(CZ) GA103/09/2007 Institutional research plan: CEZ:AV0Z30860518 Keywords : accelerogram * ANSYS * mining induced seismicity Subject RIV: DC - Siesmology, Volcanology, Earth Structure http://www.waset.org/pwaset/current.html

  14. 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...

  15. 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; Aggernæs, Bodil; Ebdrup, Bjørn H; Glenthøj, Birte; Baaré, William

    2013-01-01

    in the left rostral dorsal premotor cortex, the right presupplementary motor area and the anterior medial superior frontal gyrus bilaterally. Follow-up analyses suggested that the rostral dorsal premotor cortex and presupplementary motor area correlations were driven predominantly by the controls......Background: Prepulse inhibition (PPI) of the startle reflex is modulated by a complex neural network. Prepulse inhibition impairments are found at all stages of schizophrenia. Previous magnetic resonance imaging (MRI) studies suggest that brain correlates of PPI differ between patients 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...

  16. 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

  17. 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...... proteins involved in neuronal process extension and maintenance are both more heavily modified and more frequently regulated at a PTM level. This suggests a clear role not only for PTMs in these processes, but possibly also for heavy protein modification in general. BIOLOGICAL SIGNIFICANCE: This study...... protein-level events, this study also provides significant insight into detailed roles for individual modified proteins in the developing brain, helping to advance the understanding of the complex protein-driven processes that underlie development. Finally, the use of a novel bioinformatic analytical tool...

  18. The relationship between trait positive empathy and brain structure: a voxel-based morphometry study.

    Science.gov (United States)

    Yue, Tong; Pan, Weigang; Huang, Xiting

    2016-04-13

    Although studies relating to positive empathy have received increased attention in recent years, no studies have been carried out to explore the neural basis of positive empathy. Using a voxel-based morphometry analysis, this study investigates the relationship between trait positive empathy (as measured by the Positive Empathy Scale) and its association with brain structure in 86 healthy college students. The results indicate that an individual's ability to show positive empathy is positively correlated with the volume of gray matter in the right insula, left anterior cingulate cortex, dorsolateral prefrontal cortex, and medial prefrontal cortex. It may be suggested that the differences between the abilities of emotion processing and regulating play important roles in shaping an individual's positive empathy traits from the perspective of brain morphometry. PMID:26963166

  19. Conceptual and Data-based Investigation of Genetic Influences and Brain Asymmetry: A Twin Study of Multiple Structural Phenotypes

    OpenAIRE

    Eyler, Lisa T.; Vuoksimaa, Eero; Panizzon, Matthew S.; Fennema-Notestine, Christine; Neale, Michael C.; Chen, Chi-Hua; Jak, Amy; Franz, Carol E.; Lyons, Michael J.; Thompson, Wesley K.; Spoon, Kelly M.; Fischl, Bruce; Dale, Anders M.; Kremen, William S.

    2013-01-01

    Right–left regional cerebral differences are a feature of the human brain linked to functional abilities, aging, and neuro-developmental and mental disorders. The role of genetic factors in structural asymmetry has been incompletely studied. We analyzed data from 515 individuals (130 monozygotic twin pairs, 97 dizygotic pairs, and 61 unpaired twins) from the Vietnam Era Twin Study of Aging to answer three questions about genetic determinants of brain structural asymmetry: First, does the magn...

  20. 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...

  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. Structural Corporate Degradation Due to Too-Big-to-Fail Finance

    OpenAIRE

    Mark J Roe

    2013-01-01

    The $6 billion trading loss at JPMorgan Chase — due to the over-sized trading positions taken by the bank’s London trader, colorfully called the London Whale — induced Senate inquiries and hearings earlier this year, embarrassing the bank and its otherwise respected chief, Jamie Dimon. Severe critics saw the bank’s massive loss as showing that banks still do not have their house in order after the 2007–2009 financial crisis, but most viewed the trading debacle as cautionary, not one fundament...

  3. 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...

  4. 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

  5. Interactive 3D visualization of structural changes in the brain of a person with corticobasal syndrome

    Directory of Open Access Journals (Sweden)

    Claudia Hänel

    2014-05-01

    Full Text Available The visualization of the progression of brain tissue loss, which occurs in neurodegenerative diseases like corticobasal syndrome (CBS, is an important prerequisite to understand the course and the causes of this neurodegenerative disorder. Common workflows for visual analysis are often based on single 2D sections since in 3D visualizations more internally situated structures may be occluded by structures near the surface. The reduction of dimensions from 3D to 2D allows for an holistic view onto internal and external structures, but results in a loss of spatial information. Here, we present an application with two 3D visualization designs to resolve these challenges. First, in addition to the volume changes, the semi-transparent anatomy is displayed with an anatomical section and cortical areas for spatial orientation. Second, the principle of importance-driven volume rendering is adapted to give an unrestricted line-of-sight to relevant structures by means of a frustum-like cutout. To strengthen the benefits of the 3D visualization, we decided to provide the application next to standard desktop environments in immersive virtual environments with stereoscopic viewing as well. This improves the depth perception in general and in particular for the second design. Thus, the application presented in this work allows for aneasily comprehensible visual analysis of the extent of brain degeneration and the corresponding affected regions.

  6. 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

  7. 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 ...

  8. 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.

  9. Oscillation of electron mobility in parabolic double quantum well structure due to applied electric field

    International Nuclear Information System (INIS)

    We show that oscillation of low temperature electron mobility μ can be obtained by applying an electric field F along the growth direction of the asymmetrically barrier delta doped AlxGa1-xAs parabolic double quantum well structure. The drastic changes in the subband Fermi energies and distributions of subband wave functions as a function of F yield nonmonotonic intra- and intersubband scattering rate matrix elements mediated by intersubband effects. The oscillatory enhancement of μ, which is attributed to the subband mobilities governed by the ionized impurity scattering, magnifies with increase in well width and decrease in height of the parabolic structure potential. The results can be utilized for nanoscale low temperature device applications

  10. Dynamic investigations of various civil engineering structures due to ambient and mining tremors

    OpenAIRE

    Kuzniar Krystyna; Tatara Tadeusz

    2015-01-01

    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 seco...

  11. Are apparent findings of nonlinearity due to structural instability in economic time series?

    OpenAIRE

    Gary Koop; Simon M. Potter

    1999-01-01

    Many modeling issues and policy debates in macroeconomics depend on whether macroeconomic times series are best characterized as linear or nonlinear. If departures from linearity exist, it is important to know whether these are endogenously generated (as in, for example, a threshold autoregressive model) or whether they merely reflect changing structure over time. We advocate a Bayesian approach and show how such an approach can be implemented in practice. An empirical exercise involving seve...

  12. 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...

  13. Numerical Model of Beach Topography Evolution due to Waves and Currents: Special Emphasis on Coastal Structures

    OpenAIRE

    Pham, Thanh Nam

    2010-01-01

    The beach topography change in the nearshore zone may be induced by natural phenomena such as wind, wave, storm, tsunami, and sea level rise. However, it can also be caused by man-made structures and activities, for example, groins, detached breakwaters, seawalls, dredging, and beach nourishment. Therefore, understanding the beach topography evolution in this zone is necessary and important for coastal engineering projects, e.g., constructing harbors, maintaining navigation channels, and prot...

  14. 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...

  15. 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...

  16. 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...

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Local magnetic structure due to inhomogeneity of interaction in S=1/2 antiferromagnetic chain

    OpenAIRE

    Nishino, Masamichi; Onishi, Hiroaki; Roos, Pascal; Yamaguchi, Kizashi; Miyashita, Seiji

    1999-01-01

    We study the magnetic properties of $S=1/2$ antiferromagnetic Heisenberg chains with inhomogeneity of interaction. Using a quantum Monte Carlo method and an exact diagonalization method, we study bond-impurity effect in the uniform $S=1/2$ chain and also in the bond-alternating chain. Here `bond impurity' means a bond with strength different from those in the bulk or a defect in the alternating order. Local magnetic structures induced by bond impurities are investigated both in the ground sta...

  2. Activation of structural materials due to recoil protons in light water reactor

    International Nuclear Information System (INIS)

    The long-lived radioactivities of structural materials induced by recoil protons in BWR were estimated for land disposal of low level waste after reactor decommisioning. Reactions of interest are listed. Method of calculation of the proton spectrum in materials was developed. A program PEGASUS-P was developed by modifying PEGASUS to calculate proton induced reaction cross sections. The proton-induced activities are shown as not exceeding 1/1000 of that of a typical neutron induced nuclide, Ni-63, for cooling up to 1000 years after irradiation of 40 years. (author)

  3. 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

  4. 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...

  5. Differences in structure and magnetic behavior of Mn-AlN films due to substrate material

    International Nuclear Information System (INIS)

    The structure and magnetic behavior of Mn-AlN (Al1-xMnxN, 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. 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

  7. 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...

  8. Beam Momentum Changes due to Discharges in High-gradient Accelerator Structures

    CERN Document Server

    Palaia, Andrea; Ruber, Roger; Ekelöf, Tord

    2013-11-21

    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 of vacuum discharges, or rf breakdowns, a phenomenon whose microscopic dynamics is not yet completely understood, and whose impact on the beam can lead to a severe degradation of the collider luminosity. The understanding of the physics of rf breakdowns has therefore become a significant issue in the design of a reliable accelerator based on CLIC technology. That is addressed experimentally through the study of accelerator structures performance during high-power operations. We report on such a study carried out on a CLIC...

  9. Brain Basics

    Medline Plus

    Full Text Available ... other cells guide neurons in forming various brain structures. Neighboring neurons make connections with each other and with distant nerve cells (via axons) to form brain circuits. These circuits control specific body functions such as sleep and speech. The brain continues ...

  10. 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.

  11. 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

  12. 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.

  13. 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

  14. Functional and Structural Brain Plasticity Enhanced by Motor and Cognitive Rehabilitation in Multiple Sclerosis.

    Science.gov (United States)

    Prosperini, Luca; Piattella, Maria Cristina; Giannì, Costanza; Pantano, Patrizia

    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

  15. 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

  16. The cumulative effect of genetic polymorphisms on depression and brain structural integrity.

    Science.gov (United States)

    Kostic, Milutin; Canu, Elisa; Agosta, Federica; Munjiza, Ana; Novakovic, Ivana; Dobricic, Valerija; Maria Ferraro, Pilar; Miler Jerkovic, Vera; Pekmezovic, Tatjana; Lecic Tosevski, Dusica; Filippi, Massimo

    2016-06-01

    In major depressive disorder (MDD), the need to study multiple-gene effect on brain structure is emerging. Our aim was to assess the effect of accumulation of specific SERT, BDNF and COMT gene functional polymorphisms on brain structure in MDD patients. Seventy-seven MDD patients and 66 controls underwent a clinical assessment, genetic testing and MRI scan. Compared with controls, patients were more BDNF-Val homozygotes, COMT-Met carriers and SERT-L' carriers. Thus, subjects were split into three groups: 1. High-frequency susceptibility polymorphism group (hfSP, subjects with all three SPs); 2. Intermediate-frequency SP group (ifSP, two SPs); and 3. Low-frequency SP group (lfSP, one/none SP). Cortical thickness, volumetry of hippocampus, amygdala and subcortical structures, and white matter (WM) tract integrity were assessed. Compared to controls, hfSP patients showed thinning of the middle frontal cortex bilaterally, left frontal pole, and right lateral occipital cortex, and smaller hippocampal volume bilaterally; and both hfSP and lfSP patient groups showed thinning of the left inferior parietal cortex and reduced WM integrity of the corpus callosum. Compared to patients, hfSP controls showed greater integrity of the fronto-occipital cortices and corpus callosum. We showed that cortical prefrontal and occipital damage of MDD patients is modulated by the SP accumulation, while damage to the parietal cortex and corpus callosum seem to be independent of genetic accumulation. HfSP controls may experience protective mechanisms leading to a preserved integrity of critical cortical and WM regions. Investigating the effect of multiple genes is promising to understand the pathological mechanisms underlying MDD. Hum Brain Mapp 37:2173-2184, 2016. © 2016 Wiley Periodicals, Inc. PMID:26956059

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Correspondence between Structure and Function in the Human Brain at Rest

    Directory of Open Access Journals (Sweden)

    Judith Maxine Segall

    2012-03-01

    Full Text Available To further the understanding of basic and complex cognitive functions of the human brain, multidisciplinary neuroimaging research has explored both functional and structural connectivity. For structural connectivity, the most prevalent method has been diffusion weighted imaging, which measures the connections of large white matter bundles. Recently, functional connectivity has been measured using resting-state fMRI (rs-fMRI. Surprisingly, few studies have examined structural gray matter, which supports the BOLD response. The overall aim of this study is to explore how gray matter (GM structure corresponds to function. A cohort of 603 healthy participants was scanned on the same 3T scanner at the Mind Research Network to investigate the spatial correlations between structure and function. This was done by applying spatial independent component analysis (ICA to GMD maps, to delineate structural components based on the covariation of GMD between regions, and to rs-fMRIdata, to discover spatial patterns with common temporal features. Decomposed structural and functional components were then compared by spatial correlation. The basal ganglia network showed the highest structural to rs-functional component correlation (r=0.59. Our remaining results generally show correspondence between one structural network and several functional networks. We also studied relationships between the weights of different structural components and found networks in frontal and parietal regions showing covariation across subjects. We also identified the precuneus as a hub for in structural network correlations. In addition, we analyzed relationships between component weights and age, concluding that age has an effect on structural components.

  3. Production of fine structures in type III solar radio bursts due to turbulent density profiles

    International Nuclear Information System (INIS)

    Magnetic reconnection events in the corona release energetic electron beams along open field lines, and the beams generate radio emission at multiples of the electron plasma frequency fp to produce type III solar radio bursts. Type III bursts often exhibit irregularities in the form of flux modulations with frequency and/or local temporal advances and delays, and a type IIIb burst represents the extreme case where a type III burst is fragmented into a chain of narrowband features called striae. Remote and in situ spacecraft measurements have shown that density turbulence is ubiquitous in the corona and solar wind, and often exhibits a Kolmogorov power spectrum. In this work, we numerically investigate the effects of one-dimensional macroscopic density turbulence (along the beam direction) on the behavior of type III bursts, and find that this turbulence produces stria-like fine structures in the dynamic spectra of both fp and 2 fp radiation. Spectral and temporal fine structures in the predicted type III emission are produced by variations in the scattering path lengths and group speeds of radio emission, and in the locations and sizes of emitting volumes. Moderate turbulence levels yield flux enhancements with much broader half-power bandwidths in fp than 2 fp emission, possibly explaining the often observed type IIIb-III harmonic pairs as being where intensifications in 2 fp radiation are not resolved observationally. Larger turbulence levels producing trough-peak regions in the plasma density profile may lead to broader, resolvable intensifications in 2 fp radiation, which may account for the type IIIb-IIIb pairs that are sometimes observed.

  4. Simulation of Dose to Surrounding Normal Structures in Tangential Breast Radiotherapy Due to Setup Error

    International Nuclear Information System (INIS)

    Setup error plays a significant role in the final treatment outcome in radiotherapy. The effect of setup error on the planning target volume (PTV) and surrounding critical structures has been studied and the maximum allowed tolerance in setup error with minimal complications to the surrounding critical structure and acceptable tumor control probability is determined. Twelve patients were selected for this study after breast conservation surgery, wherein 8 patients were right-sided and 4 were left-sided breast. Tangential fields were placed on the 3-dimensional-computed tomography (3D-CT) dataset by isocentric technique and the dose to the PTV, ipsilateral lung (IL), contralateral lung (CLL), contralateral breast (CLB), heart, and liver were then computed from dose-volume histograms (DVHs). The planning isocenter was shifted for 3 and 10 mm in all 3 directions (X, Y, Z) to simulate the setup error encountered during treatment. Dosimetric studies were performed for each patient for PTV according to ICRU 50 guidelines: mean doses to PTV, IL, CLL, heart, CLB, liver, and percentage of lung volume that received a dose of 20 Gy or more (V20); percentage of heart volume that received a dose of 30 Gy or more (V30); and volume of liver that received a dose of 50 Gy or more (V50) were calculated for all of the above-mentioned isocenter shifts and compared to the results with zero isocenter shift. Simulation of different isocenter shifts in all 3 directions showed that the isocentric shifts along the posterior direction had a very significant effect on the dose to the heart, IL, CLL, and CLB, which was followed by the lateral direction. The setup error in isocenter should be strictly kept below 3 mm. The study shows that isocenter verification in the case of tangential fields should be performed to reduce future complications to adjacent normal tissues

  5. 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.)

  6. 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

    2016-06-01

    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. PMID:26052731

  7. Structural activation calculations due to proton beam loss in the APT accelerator design

    International Nuclear Information System (INIS)

    For the new, high-power accelerators currently being designed, the amount of activation of the accelerator structure has become an important issue. To quantify this activation, a methodology was utilized that coupled transport and depletion codes to obtain dose rate estimates at several locations near the accelerator. This research focused on the 20 and 100 MeV sections of the Bridge-Coupled Drift Tube Linear Accelerator. The peak dose rate was found to be approximately 6 mR/hr in the 100 MeV section near the quadrupoles at a 25-cm radius for an assumed beam loss of 1 nA/m. It was determined that the activation was dominated by the proton interactions and subsequent spallation product generation, as opposed to the presence of the generated neutrons. The worst contributors were the spallation products created by proton bombardment of iron, and the worst component was the beam pipe, which consists mostly of iron. No definitive conclusions about the feasibility of hands-on maintenance can be determined, as the design is still not finalized

  8. Structural and hydrological alterations of soil due to addition of coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Yunusa, Isa A.M. [New England Univ., Armidale, NSW (Australia). School of Environmental and Rural Sciences; Manoharan, V.; Skilbeck, C. Greg; Eamus, Derek [University of Technology, Sydney, Broadway, NSW (Australia). Dept. of Environmental Science; Odeh, Inakwu O.A. [Sydney Univ., NSW (Australia). Faculty of Agriculture, Food and Natural Resources; Shrestha, Surendra [Western Sydney Univ., Penrith South DC, NSW (Australia). School of Engineering, College of Health and Science

    2011-04-15

    Purpose: We tested the potential of using coal fly ash for improving the physical and hydrological characteristics of coarse and medium-textured agricultural soils. Materials and methods: Acidic (FWA) and alkaline (FNSW) fly ashes were used to amend a range of representative agricultural soils. In the first experiment, fly ash was applied to the top 10 cm of 1-m long intact cores of a sandy loam soil at rates of 0, 12, 36 or 108 Mg/ha and sown with canola; after harvest, bulk density (BD), aggregate stability and mean weight diameter (MWD) were measured on the soil. In the second experiment, we assessed water retention at field capacity (-300 kPa) and permanent wilting point (-1,500 kPa) for sandy and loamy soils amended with FNSW at 0.0-16% (w/w). The third experiment used rainfall simulation to assess erodibility of sandy and loamy soils mixed with FNSW at rates of 0, 5 or 20 Mg/ha. Results and discussion: In the first experiment, fly ash had no significant effect on MWD of the soil. The BD in the 0-10 cm layer (topsoil) was increased with addition of FWA, while FNSW applied at 108 Mg/ha reduced BD, relative to the control treatment. This was because FNSW had lower particle and bulk densities than FWA and the test soils. Ash addition increased macro-aggregation, significantly so in the 10-20 cm layer (subsurface layer), by reducing the percentages of micro-aggregates and silt + clay particles. Thus, macro-aggregation was positively correlated (p < 0.01) with MWD, but both were inversely correlated (p < 0.01) with micro-aggregates. In the second experiment, addition of fly ash enhanced plant water availability by increasing water retention at field capacity by threefold in the sandy soil and 1.5-fold in the loamy sand, but water retention at permanent wilting point was not affected. In Experiment 3, the addition of ash at 20 Mg/ha, but not at 5 Mg/ha, increased turbidity of runoff water from the amended soil due to the dispersal of fine particles by the impact of

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. 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)

  14. 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)].

  15. 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.

  16. 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.

  17. Structural Brain Abnormalities in Juvenile Myoclonic Epilepsy Patients: Volumetry and Voxel-Based Morphometry

    International Nuclear Information System (INIS)

    We aimed to find structural brain abnormalities in juvenile myoclonic epilepsy (JME) patients. The volumes of the cerebrum, hippocampus and frontal lobe and the area of the corpus callosum's subdivisions were all semiautomatically measured, and then optimized voxel-based morphometry (VBM) was performed in 19 JME patients and 19 age/gender matched normal controls. The rostrum and rostral body of the corpus callosum and the left hippocampus were significantly smaller than those of the normal controls, whereas the volume of the JME's left frontal lobe was significantly larger than that of the controls. The area of the rostral body had a significant positive correlation with the age of seizure onset (r=0.56, p=0.012), and the volume of the right frontal lobe had a significant negative correlation with the duration of disease (r=-0.51, p=0.025). On the VBM, the gray matter concentration of the prefrontal lobe (bilateral gyri rectus, anterior orbital gyri, left anterior middle frontal gyrus and right anterior superior frontal gyrus) was decreased in the JME group (corrected p<0.05). The JME patients showed complex structural abnormalities in the corpus callosum, frontal lobe and hippocampus, and also a decreased gray matter concentration of the prefrontal region, which all suggests there is an abnormal neural network in the JME brain

  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. Seeded growth of beta-amyloid fibrils from Alzheimer's brain-derived fibrils produces a distinct fibril structure.

    Science.gov (United States)

    Paravastu, Anant K; Qahwash, Isam; Leapman, Richard D; Meredith, Stephen C; Tycko, Robert

    2009-05-01

    Studies by solid-state nuclear magnetic resonance (NMR) of amyloid fibrils prepared in vitro from synthetic 40-residue beta-amyloid (Abeta(1-40)) peptides have shown that the molecular structure of Abeta(1-40) fibrils is not uniquely determined by amino acid sequence. Instead, the fibril structure depends on the precise details of growth conditions. The molecular structures of beta-amyloid fibrils that develop in Alzheimer's disease (AD) are therefore uncertain. We demonstrate through thioflavin T fluorescence and electron microscopy that fibrils extracted from brain tissue of deceased AD patients can be used to seed the growth of synthetic Abeta(1-40) fibrils, allowing preparation of fibrils with isotopic labeling and in sufficient quantities for solid-state NMR and other measurements. Because amyloid structures propagate themselves in seeded growth, as shown in previous studies, the molecular structures of brain-seeded synthetic Abeta(1-40) fibrils most likely reflect structures that are present in AD brain. Solid-state (13)C NMR spectra of fibril samples seeded with brain material from two AD patients were found to be nearly identical, indicating the same molecular structures. Spectra of an unseeded control sample indicate greater structural heterogeneity. (13)C chemical shifts and other NMR data indicate that the predominant molecular structure in brain-seeded fibrils differs from the structures of purely synthetic Abeta(1-40) fibrils that have been characterized in detail previously. These results demonstrate a new approach to detailed structural characterization of amyloid fibrils that develop in human tissue, and to investigations of possible correlations between fibril structure and the degree of cognitive impairment and neurodegeneration in AD. PMID:19376973

  20. 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

  1. White matter cerebral blood flow is inversely correlated with structural and functional connectivity in the human brain

    OpenAIRE

    Aslan, Sina; Huang, Hao; Uh, Jinsoo; Mishra, Virendra; Xiao, Guanghua; van Osch, Matthias J.P.; Lu, Hanzhang

    2011-01-01

    White matter provides anatomic connections among brain regions and has received increasing attention in understanding brain intrinsic networks and neurological disorders. Despite significant progresses made in characterizing the white matter’s structural properties using post-mortem techniques and in vivo diffusion-tensor-imaging (DTI) methods, its physiology remains poorly understood. In the present study, cerebral blood flow (CBF) of the white matter was investigated on a fiber-tract-specif...

  2. Anorexia nervosa is linked to reduced brain structure in reward and somatosensory regions : a meta-analysis of VBM studies

    OpenAIRE

    Titova, Olga E.; Hjorth, Olof C; Schiöth, Helgi B.; Brooks, Samantha J.

    2013-01-01

    BACKGROUND Structural imaging studies demonstrate brain tissue abnormalities in eating disorders, yet a quantitative analysis has not been done. METHODS In global and regional meta-analyses of 9 voxel-based morphometry (VBM) studies, with a total of 228 eating disorder participants (currently ill with anorexia nervosa), and 240 age-matched healthy controls, we compare brain volumes using global and regional analyses. RESULTS Anorexia nervosa (AN) patients have global reductions in gray (effec...

  3. 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.

  4. Structural changes of small amplitude kinetic Alfvén solitary waves due to second-order corrections

    International Nuclear Information System (INIS)

    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

  5. Structural changes of small amplitude kinetic Alfvén solitary waves due to second-order corrections

    Science.gov (United States)

    Choi, Cheong R.

    2015-10-01

    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.

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

    Science.gov (United States)

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

    2013-09-15

    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 volume was the highest in the trauma control group, followed 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, occipital 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. PMID:25206550

  7. 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.

  8. 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.

  9. Structural, chemical surface and transport modifications of regenerated cellulose dense membranes due to low-dose γ-radiation

    International Nuclear Information System (INIS)

    Research highlights: → Low dose γ-radiation causes slight structural, chemical and morphological changes on regenerated cellulose films. → Induced structural changes increase the fragility of irradiated films. → Structural modifications reduce ion permeability of films. - Abstract: Modifications caused in commercial dense regenerated cellulose (RC) flat membranes by low-dose γ-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.

  10. 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.

  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. 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.

  13. 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.)

  14. 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.)

  15. 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.

  16. Flows of a Vapor due to Phase Change Processes at the Condensed Phases with Temperature Fields as their Internal Structures

    Science.gov (United States)

    Onishi, Yoshimoto; Takeshi, Ooshida

    2005-05-01

    Transient to steady motions of a vapor caused by the evaporation and condensation processes occurring at the condensed phases placed in parallel have been studied based on the Boltzmann equation of BGK type. As the internal structures of the condensed phases, the temperature fields are taken into account. Because of this, the temperatures of the interfaces become unknown parameters and, therefore, the condition of the continuity of energy flow across the interface has to be imposed simultaneously with the conditions so far used for the cases with no internal structures. This extra condition gives great difficulty in the numerical simulations but this has been surmounted by a simple method developed earlier in our laboratory. The present analysis has also incorporated a certain kind of imperfectness of the interface in the boundary conditions by the introduction of a simple parameter, called the imperfectness parameter here, first proposed by Wortberg and his colleague. The results obtained describe appropriately the development of the transient flow fields due to the processes of evaporation and condensation at the interfaces across which the continuous energy flows are taking place. Some of the features worth to be mentioned are that 1) a certain value of the latent heat parameter gives the maxima of the mass and energy flows. This fact, which is newly found here, is due to the coupling effects of the latent heat parameter and the existence of the internal structures of the condensed phases; 2) the negative temperature gradient phenomenon, a well-known phenomenon at steady state in weak evaporation and condensation problems between the two condensed phases having no internal structures, seems to be non-existent in the present case with internal structures; 3) the negative mass flow phenomenon, first noticed and discussed by Sone and Onishi, seems to be non-existent at steady state but this surely manifests itself in a short period of time during the transitional

  17. 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

  18. Peripheral vagus nerve stimulation significantly affects lipid composition and protein secondary structure within dopamine-related brain regions in rats.

    Science.gov (United States)

    Surowka, Artur Dawid; Krygowska-Wajs, Anna; Ziomber, Agata; Thor, Piotr; Chrobak, Adrian Andrzej; Szczerbowska-Boruchowska, Magdalena

    2015-06-01

    Recent immunohistochemical studies point to the dorsal motor nucleus of the vagus nerve as the point of departure of initial changes which are related to the gradual pathological developments in the dopaminergic system. In the light of current investigations, it is likely that biochemical changes within the peripheral nervous system may influence the physiology of the dopaminergic system, suggesting a putative role for it in the development of neurodegenerative disorders. By using Fourier transform infrared microspectroscopy, coupled with statistical analysis, we examined the effect of chronic, unilateral electrical vagus nerve stimulation on changes in lipid composition and in protein secondary structure within dopamine-related brain structures in rats. It was found that the chronic vagal nerve stimulation strongly affects the chain length of fatty acids within the ventral tegmental area, nucleus accumbens, substantia nigra, striatum, dorsal motor nucleus of vagus and the motor cortex. In particular, the level of lipid unsaturation was found significantly increasing in the ventral tegmental area, substantia nigra and motor cortex as a result of vagal nerve stimulation. When it comes to changes in protein secondary structure, we could see that the mesolimbic, mesocortical and nigrostriatal dopaminergic pathways are particularly affected by vagus nerve stimulation. This is due to the co-occurrence of statistically significant changes in the content of non-ordered structure components, alpha helices, beta sheets, and the total area of Amide I. Macromolecular changes caused by peripheral vagus nerve stimulation may highlight a potential connection between the gastrointestinal system and the central nervous system in rat during the development of neurodegenerative disorders. PMID:25893743

  19. Brain structural changes and their correlation with vascular disease in type 2 diabetes mellitus patients: a voxel-based morphometric study

    OpenAIRE

    Wang, Chunxia; Fu, Kailiang; Liu, Huaijun; Xing, Fei; Zhang, Songyun

    2014-01-01

    Voxel-based morphometry has been used in the study of alterations in brain structure in type 1 diabetes mellitus patients. These changes are associated with clinical indices. The age at onset, pathogenesis, and treatment of type 1 diabetes mellitus are different from those for type 2 diabetes mellitus. Thus, type 1 and type 2 diabetes mellitus may have different impacts on brain structure. Only a few studies of the alterations in brain structure in type 2 diabetes mellitus patients using voxe...

  20. Structural and functional brain rewiring clarifies preserved interhemispheric transfer in humans born without the corpus callosum

    Science.gov (United States)

    Tovar-Moll, Fernanda; Monteiro, Myriam; Andrade, Juliana; Bramati, Ivanei E.; Vianna-Barbosa, Rodrigo; Marins, Theo; Rodrigues, Erika; Dantas, Natalia; Behrens, Timothy E. J.; de Oliveira-Souza, Ricardo; Moll, Jorge; Lent, Roberto

    2014-01-01

    Why do humans born without the corpus callosum, the major interhemispheric commissure, lack the disconnection syndrome classically described in callosotomized patients? This paradox was discovered by Nobel laureate Roger Sperry in 1968, and has remained unsolved since then. To tackle the hypothesis that alternative neural pathways could explain this puzzle, we investigated patients with callosal dysgenesis using structural and functional neuroimaging, as well as neuropsychological assessments. We identified two anomalous white-matter tracts by deterministic and probabilistic tractography, and provide supporting resting-state functional neuroimaging and neuropsychological evidence for their functional role in preserved interhemispheric transfer of complex tactile information, such as object recognition. These compensatory pathways connect the homotopic posterior parietal cortical areas (Brodmann areas 39 and surroundings) via the posterior and anterior commissures. We propose that anomalous brain circuitry of callosal dysgenesis is determined by long-distance plasticity, a set of hardware changes occurring in the developing brain after pathological interference. So far unknown, these pathological changes somehow divert growing axons away from the dorsal midline, creating alternative tracts through the ventral forebrain and the dorsal midbrain midline, with partial compensatory effects to the interhemispheric transfer of cortical function. PMID:24821757

  1. 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

  2. Structural brain differences and cognitive functioning related to body mass index in older females.

    Science.gov (United States)

    Walther, Katrin; Birdsill, Alex C; Glisky, Elizabeth L; Ryan, Lee

    2010-07-01

    Little is known about the effect of obesity on brain structures and cognition in healthy older adults. This study examined the association between body mass index (BMI), regional volume differences in gray and white matter measured by magnetic resonance imaging (MRI), and cognitive functioning in older females. Participants included 95 community-dwelling older females (ages 52-92 years) who underwent extensive neuropsychological testing and high-resolution MRI scanning. Optimized voxel-based morphometry techniques were employed to determine the correlation between BMI and regional gray and white matter volumes. Volumes of significant regions were then correlated with cognitive functioning. Higher BMI was associated with decreased gray matter volumes in the left orbitofrontal, right inferior frontal, and right precentral gyri, a right posterior region including the parahippocampal, fusiform, and lingual gyri, and right cerebellar regions, as well as increased volumes of white matter in the frontal, temporal, and parietal lobes, even when hypertension was considered. Compared to normal weight women, obese women performed poorer on tests of executive functioning. Smaller gray matter volume in the left orbitofrontal region was associated with lower executive functioning. Additionally, despite the lack of significant group differences in memory and visuomotor speed, gray and white matter volumes predicted performance on these measures. The results provide additional evidence for a negative link between increased body fat and brain functioning in older females. PMID:19998366

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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

  8. Predicting the variability in the wavelength structures of the incoming radiation due to ozone layer depletion at Arabian sea

    International Nuclear Information System (INIS)

    In this communication we have investigated the variability in the wavelength structures of the radiation due to ozone layer depletion (OLD) using empirical modeling approach. A model has been developed for evaluating sea surface temperature using stratospheric ozone filter. This filter has been formulated taking into account of the ozone layer depletion (OLD) strategy for Pakistan atmospheric regions. For making predictions of various wavelength, stochastic analysis is implemented here for observing future prospects of the coming radiation. These predictions are useful for public, private and government organizations. (author)

  9. Heritability of brain structure and glutamate levels in the anterior cingulate and left thalamus assessed with MR: A twin study

    DEFF Research Database (Denmark)

    Broberg, Brian Villumsen; Legind, Christian Stefan; Mandl, Rene C W;

    Heritability of brain structure and glutamate levels in the anterior cingulate and left thalamus assessed with MR: A twin study Brian V. Broberg1,2; Christian S. Legind1,2, Rene C. Mandl1,3, Maria H. Jensen1, Simon J. Anhøj1,2, Rikke Hilker1, Egill Rostrup1,2, Birte Y. Glenthøj1 Author affiliations......, Copenhagen, Denmark 3. Brain Center Rudolf Magnus, Dept. of Psychiatry, UMC Utrecht, the Netherlands Background Changes in global and regional brain volumes in schizophrenia are known to be heritable and to cosegregate with illness (McDonald et al., 2002; Peper et al., 2007). Changes in neurochemistry — and...... particularly changes in glutamate — are most likely linked to changes in brain volume (Kraguljac et al., 2013) but investigations on heritability of glutamate levels are sparse. Several genes associated with glutamate transmission were suggested to be involved in the pathophysiology of schizophrenia (Ripke et...

  10. 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

  11. 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.

  12. [Brain structures and functional pecularities in children with mental disorders and transcranial direct current stimulation].

    Science.gov (United States)

    Kozhushko, N Iu; Kropotov, Iu D; Matveev, Iu K; Semivolos, V I; Tereshchenko, E P; Holiavin, A I

    2014-01-01

    This research represents MRI and EEG-investigation in children with mental disorders perinatal genesis during tDCS. In 70% cases brain structures damages don't found or were minimal. On the contrary, in 77% cases α-rhythm of EEG in parietal-occipital areas was non-regular. Functional insufficiency can as a basis of high efficiency tDCS by children. In cases with autism spectrum disorders the Subscales of Woodcock-Jonson were used for the quantitative estimation of efficiency of the course of treatment with tDCS. Positive changes after the course of tDCS were revealed in psychic state, speech comprehension, communication, practical and speech experience, fine motor skills and social integration. PMID:25707217

  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. 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.

  15. 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

    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 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...... 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...

  16. 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.

  17. Probabilistic anatomical labeling of brain structures using statistical probabilistic anatomical maps

    International Nuclear Information System (INIS)

    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

  18. Neurochemical–structural changes evaluation of brain in patients with obstructive sleep apnea syndrome

    International Nuclear Information System (INIS)

    Purpose: To evaluate neurochemical and structural changes in the patients with newly diagnosed obstructive sleep apnea syndrome (OSAS) by MR spectroscopy (MRS), T2 relaxometry, and diffusion weighted imaging (DWI). Material and methods: Following the acquisition of routine cranial MR, MRS, T2 relaxometry, and DWI images; spectroscopic metabolite ratios and DWI–T2 relaxometry findings of the thalami, hippocampi, frontal white matter (FWM) and frontal cortex of 24 OSAS patients and 9 controls were statistically compared. The relationship between two groups was evaluated with Mann–Whitney test. Results: Spectroscopic measurements in the frontal cortex and frontal white matter of the OSAS patients revealed significantly lower NAA/Cr ratios than those of the control group (P = 0.004 and P = 0.006, respectively). The measurements in the frontal white matter of the OSAS patients exhibited significantly lower NAA/Cho ratios compared with those of the control group (P = 0.005). Thalamic Cho/Cr ratios of the patient group were significantly higher than those of the control group (P = 0.002). In terms of the ADC–T2 relaxometry values, there was no significant relationship between the patient and the control groups (P > 0.05). Conclusion: MRS is a useful and non-invasive modality in showing neurochemical changes in various regions of the brain but our data does not show any change on diffusion weighting or T2 quantification in the OSAS group. DWI and T2 relaxometry appear to be not effective techniques to evaluate the brain structural changes of the patients with newly diagnosed OSAS.

  19. Segmentation of internal brain structures in three-dimensional nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    For neurological studies, the in vivo aspect of imaging systems is very attractive. Brain images are currently a classical tool used in clinical routine and research. The most appropriate system to observe brain anatomy is tridimensional magnetic resonance imaging, and a major issue of image processing is to segment automatically cerebral structures. This is the scope of our thesis. The number of applications is steadily growing: morphometric measurements, pathology detection, surgery planning, getting a reference for functional studies,a and so forth. The use of pattern recognition to classify the different cerebral tissues from the only radiometric levels of the images is limited. Even supervised, these methods can not lead to distinguish easily several classes of grey matter. When these methods are automatic, their use has to be empirical in order to ensure robust results, and has to be restricted to regions of interest in order to get reliable results. As these methods do not fully respect the spatial consistency of classes in the images, we have introduced contextual information with the help of different formalisms. With Markovian regularization, we have shown that energetic terms of localization permit the separation of two grey classes: cortex and central nuclei. With mathematical morphology, we have proposed processing chains dedicated to several cerebral objects; in particular, brain segmentation is robust and reproducible, and we have successfully obtained individual markers for lateral ventricles, caudate nuclei, putamen and thalami. We have also proposed a contextual method to estimate pure tissue characteristics from a rough segmentation. Our main contribution has been to present a recognition method which is progressive and atlas guided. The originality of this method is manifold. At first, it takes into account structural information processed as flexible spatial constraints the formalism of which relies on fuzzy set theory and information fusion

  20. Identifying Lesions on Structural Brain Images-Validation of the Method and Application to Neuropsychological Patients

    Science.gov (United States)

    Stamatakis, E.A.; Tyler, L.K.

    2005-01-01

    The study of neuropsychological disorders has been greatly facilitated by the localization of brain lesions on MRI scans. Current popular approaches for the assessment of MRI brain scans mostly depend on the successful segmentation of the brain into grey and white matter. These methods cannot be used effectively with large lesions because lesions…

  1. 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.

  2. 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

  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. 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

  5. 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.

  6. Structural abnormalities of the brain in schizophrenia: sex differences in the Cantabria First Episode of Schizophrenia Study.

    Science.gov (United States)

    Vázquez-Barquero, J L; Cuesta Núñez, M J; Quintana Pando, F; de la Varga, M; Herrera Castanedo, S; Dunn, G

    1995-11-01

    This paper examines structural brain abnormalities, as evaluated by the CT scan, in first episodes of schizophrenia and their association with sociodemographic, diagnostic and clinical variables. The investigation included all patients with a first episode of schizophrenia who, over a 2-year period, made contact with any of the public mental health services of the Autonomous Region of Cantabria in Northern Spain. Diagnostic and clinical characteristics were evaluated through the use of the Spanish version of the Present State Examination (PSE-9) and the Scales for the Assessment of Positive and Negative Symptoms (SANS and SAPS respectively). The study demonstrated the presence of structural brain abnormalities in this sample of first episode schizophrenics. These abnormalities were mainly expressed in the presence of larger VBR for schizophrenic patients than in the controls, these findings being more marked in women than in men. We failed to reveal, however, any evidence of an association of these brain abnormalities with diagnostic or clinical characteristics. PMID:8637954

  7. 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.

  8. Nonmonotonous electron mobility due to structurally induced resonant coupling of subband states in an asymmetric double quantum well

    International Nuclear Information System (INIS)

    We show that sharp nonmonotic variation of low temperature electron mobility μ can be achieved in GaAs/AlxGa1-xAs 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

  9. Cross-Sectional and Longitudinal Abnormalities in Brain Structure in Children with Severe Mood Dysregulation or Bipolar Disorder

    Science.gov (United States)

    Adleman, Nancy E.; Fromm, Stephen J.; Razdan, Varun; Kayser, Reilly; Dickstein, Daniel P.; Brotman, Melissa A.; Pine, Daniel S.; Leibenluft, Ellen

    2012-01-01

    Background: There is debate as to whether chronic irritability (operationalized as severe mood dysregulation, SMD) is a developmental form of bipolar disorder (BD). Although structural brain abnormalities in BD have been demonstrated, no study compares neuroanatomy among SMD, BD, and healthy volunteers (HV) either cross-sectionally or over time.…

  10. Relation between aerobic fitness and brain structures in amnestic mild cognitive impairment elderly.

    Science.gov (United States)

    Teixeira, Camila Vieira Ligo; Rezende, Thiago J R; Weiler, Marina; Nogueira, Mateus H; Campos, Brunno M; Pegoraro, Luiz F L; Vicentini, Jessica E; Scriptore, Gabriela; Cendes, Fernando; Balthazar, Marcio L F

    2016-06-01

    Mild cognitive impairment (aMCI) is a clinical condition, with high risk to develop Alzheimer's disease. Physical exercise may have positive effect on cognition and brain structure in older adults. However, it is still under research whether these influences are true on aMCI subjects with low Ab_42 and high total tau in cerebrospinal fluid (CSF), which is considered a biomarker for AD. Therefore, we aimed to investigate a possible relation between aerobic fitness (AF) and gray matter (GM) volume and AF and white matter (WM) integrity in aMCI with a CSF biomarker. Twenty-two participants with aMCI acquired the images on a 3.0-T MRI. AF was assessed by a graded exercise test on a treadmill. Voxel-based morphometry and tract-based spatial statistic methods were used to analyze the GM volume and WM microstructural integrity, respectively. We correlated AF and GM volume and WM integrity in aMCI (p < 0.05, FWE corrected, cluster with at least five voxels). There was a positive relation between AF and GM volume mostly in frontal superior cortex. In WM integrity, AF was positively correlated with fractional anisotropy and negatively correlated with mean diffusivity and radial diffusivity, all in the same tracts that interconnect frontal, temporal, parietal, and occipital areas (longitudinal fasciculus, fronto-occipital fasciculus, and corpus callosum). These results suggest that aerobic fitness may have a positive influence on protection of brain even in aMCI CSF biomarker, a high-risk population to convert to AD. PMID:27106271

  11. Structural brain abnormalities in postural tachycardia syndrome: A VBM-DARTEL study

    Directory of Open Access Journals (Sweden)

    Satoshi eUmeda

    2015-03-01

    Full Text Available Postural tachycardia syndrome (PoTS, a form of dysautonomia, is characterized by orthostatic intolerance, and is frequently accompanied by a range of symptoms including palpitations, lightheadedness, clouding of thought, blurred vision, fatigue, anxiety and depression. Although the estimated prevalence of PoTS is approximately 5-10 times ascommon as the better-known condition orthostatic hypotension, the neural substrates of the syndrome are poorly characterized. In the present study, we used magnetic resonance imaging (MRI with voxel-based morphometry (VBM applying the diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL procedure to examine variation in regional brain structure associated with PoTS. We recruited eleven patients with established PoTS and twenty-three age-matched normal controls. Group comparison of grey matter volume revealed diminished grey matter volume within the left anterior insula, right middle frontal gyrus and right cingulate gyrus in the PoTS group. We also observed lower white matter volume beneath the precentral gyrus and paracentral lobule, right pre- and post-central gyrus, paracentral lobule and superior frontal gyrus in PoTS patients. Subsequent ROI analyses revealed significant negative correlations between left insula volume and trait anxiety and depression scores. Together, these findings of structural differences, particularly within insular and cingulate components of the salience network, suggest a link between dysregulated physiological reactions arising from compromised central autonomic control (and interoceptive representation and increased vulnerability to psychiatric symptoms in PoTS patients.

  12. Predicting healthy older adult's brain age based on structural connectivity networks using artificial neural networks.

    Science.gov (United States)

    Lin, Lan; Jin, Cong; Fu, Zhenrong; Zhang, Baiwen; Bin, Guangyu; Wu, Shuicai

    2016-03-01

    Brain ageing is followed by changes of the connectivity of white matter (WM) and changes of the grey matter (GM) concentration. Neurodegenerative disease is more vulnerable to an accelerated brain ageing, which is associated with prospective cognitive decline and disease severity. Accurate detection of accelerated ageing based on brain network analysis has a great potential for early interventions designed to hinder atypical brain changes. To capture the brain ageing, we proposed a novel computational approach for modeling the 112 normal older subjects (aged 50-79 years) brain age by connectivity analyses of networks of the brain. Our proposed method applied principal component analysis (PCA) to reduce the redundancy in network topological parameters. Back propagation artificial neural network (BPANN) improved by hybrid genetic algorithm (GA) and Levenberg-Marquardt (LM) algorithm is established to model the relation among principal components (PCs) and brain age. The predicted brain age is strongly correlated with chronological age (r=0.8). The model has mean absolute error (MAE) of 4.29 years. Therefore, we believe the method can provide a possible way to quantitatively describe the typical and atypical network organization of human brain and serve as a biomarker for presymptomatic detection of neurodegenerative diseases in the future. PMID:26718834

  13. 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

  14. Quantitative differences in adhesiveness of type 1 fimbriated Escherichia coli due to structural differences in fimH genes.

    Science.gov (United States)

    Sokurenko, E V; Courtney, H S; Maslow, J; Siitonen, A; Hasty, D L

    1995-01-01

    Type 1 fimbriae are heteropolymeric surface organelles responsible for the D-mannose-sensitive (MS) adhesion of Escherichia coli. We recently reported that variation of receptor specificity of type 1 fimbriae can result solely from minor alterations in the structure of the gene for the FimH adhesin subunit. To further study the relationship between allelic variation of the fimH gene and adhesive properties of type 1 fimbriae, the fimH genes from five additional strains were cloned and used to complement the FimH deletion in E. coli KB18. When the parental and recombinant strains were tested for adhesion to immobilized mannan, a wide quantitative range in the ability of bacteria to adhere was noted. The differences in adhesion do not appear to be due to differences in the levels of fimbriation or relative levels of incorporation of FimH, because these parameters were similar in low-adhesion and high-adhesion strains. The nucleotide sequence for each of the fimH genes was determined. Analysis of deduced FimH sequences allowed identification of two sequence homology groups, based on the presence of Asn-70 and Ser-78 or Ser-70 and Asn-78 residues. The consensus sequences for each group conferred very low adhesion activity, and this low-adhesion phenotype predominated among a group of 43 fecal isolates. Strains isolated from a different host niche, the urinary tract, expressed type 1 fimbriae that conferred an increased level of adhesion. The results presented here strongly suggest that the quantitative variations in MS adhesion are due primarily to structural differences in the FimH adhesin. The observed differences in MS adhesion among populations of E. coli isolated from different host niches call attention to the possibility that phenotypic variants of FimH may play a functional role in populations dynamics. PMID:7601831

  15. Integrating Structure to Protein-Protein Interaction Networks That Drive Metastasis to Brain and Lung in Breast Cancer

    OpenAIRE

    H Billur Engin; Emre Guney; Ozlem Keskin; Baldo Oliva; Attila Gursoy

    2013-01-01

    Integrating Structure to Protein-Protein Interaction Networks That Drive Metastasis to Brain and Lung in Breast Cancer H. Billur Engin1, Emre Guney2, Ozlem Keskin1, Baldo Oliva2, Attila Gursoy1* 1 Center for Computational Biology and Bioinformatics and College of Engineering, Koc University, Istanbul, Turkey, 2 Structural Bioinformatics Group (GRIB), Universitat Pompeu Fabra Abstract Blocking specific protein interactions can lead to human diseases. Accordingly, protein i...

  16. Integrating structure to protein-protein interaction networks that drive metastasis to brain and lung in breast cancer

    OpenAIRE

    Engin, H Billur; G??ney, Emre, 1983-; Keskin, Ozlem; Oliva Miguel, Baldomero; Gursoy, Attila

    2013-01-01

    Integrating Structure to Protein-Protein Interaction Networks That Drive Metastasis to Brain and Lung in Breast Cancer H. Billur Engin1, Emre Guney2, Ozlem Keskin1, Baldo Oliva2, Attila Gursoy1* 1 Center for Computational Biology and Bioinformatics and College of Engineering, Koc University, Istanbul, Turkey, 2 Structural Bioinformatics Group (GRIB), Universitat Pompeu Fabra Abstract Blocking specific protein interactions can lead to human diseases. Accordingly, protein i...

  17. Mapping pathological changes in brain structure by combining T1- and T2-weighted MR imaging data

    International Nuclear Information System (INIS)

    A workflow based on the ratio between standardized T1-weighted (T1-w) and T2-weighted (T2-w) MR images has been proposed as a new tool to study brain structure. This approach was previously used to map structural properties in the healthy brain. Here, we evaluate whether the T1-w/T2-w approach can support the assessment of structural impairments in the diseased brain. We use schizophrenia data to demonstrate the potential clinical utility of the technique. We analyzed T1-w and T2-w images of 36 schizophrenic patients and 35 age-matched controls. These were collected for the Function Biomedical Informatics Research Network (fBIRN) collaborative project, which had an IRB approval and followed the HIPAA guidelines. We computed T1-w/T2-w images for each individual and compared intensities in schizophrenic and control groups on a voxel-wise basis, as well as in regions of interest (ROIs). Our results revealed that the T1-w/T2-w image permits to discriminate brain regions showing group-level differences between patients and controls with greater accuracy than conventional T1-w and T2-w images. Both the ROIs and the voxel-wise analysis showed globally reduced gray and white matter values in patients compared to controls. Significantly reduced values were found in regions such as insula, primary auditory cortex, hippocampus, inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus. Our findings were consistent with previous meta-analyses in schizophrenia corroborating the hypothesis of a potential ''disconnection'' syndrome in conjunction with structural alterations in local gray matter regions. Overall, our study suggested that the T1-w/T2-w technique permits to reliably map structural differences between the brains of patients and healthy individuals. (orig.)

  18. High-throughput RNA sequencing reveals structural differences of orthologous brain-expressed genes between western lowland gorillas and humans.

    Science.gov (United States)

    Lipovich, Leonard; Hou, Zhuo-Cheng; Jia, Hui; Sinkler, Christopher; McGowen, Michael; Sterner, Kirstin N; Weckle, Amy; Sugalski, Amara B; Pipes, Lenore; Gatti, Domenico L; Mason, Christopher E; Sherwood, Chet C; Hof, Patrick R; Kuzawa, Christopher W; Grossman, Lawrence I; Goodman, Morris; Wildman, Derek E

    2016-02-01

    The human brain and human cognitive abilities are strikingly different from those of other great apes despite relatively modest genome sequence divergence. However, little is presently known about the interspecies divergence in gene structure and transcription that might contribute to these phenotypic differences. To date, most comparative studies of gene structure in the brain have examined humans, chimpanzees, and macaque monkeys. To add to this body of knowledge, we analyze here the brain transcriptome of the western lowland gorilla (Gorilla gorilla gorilla), an African great ape species that is phylogenetically closely related to humans, but with a brain that is approximately one-third the size. Manual transcriptome curation from a sample of the planum temporale region of the neocortex revealed 12 protein-coding genes and one noncoding-RNA gene with exons in the gorilla unmatched by public transcriptome data from the orthologous human loci. These interspecies gene structure differences accounted for a total of 134 amino acids in proteins found in the gorilla that were absent from protein products of the orthologous human genes. Proteins varying in structure between human and gorilla were involved in immunity and energy metabolism, suggesting their relevance to phenotypic differences. This gorilla neocortical transcriptome comprises an empirical, not homology- or prediction-driven, resource for orthologous gene comparisons between human and gorilla. These findings provide a unique repository of the sequences and structures of thousands of genes transcribed in the gorilla brain, pointing to candidate genes that may contribute to the traits distinguishing humans from other closely related great apes. PMID:26132897

  19. Mapping pathological changes in brain structure by combining T1- and T2-weighted MR imaging data

    Energy Technology Data Exchange (ETDEWEB)

    Ganzetti, Marco; Mantini, Dante [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); University of Oxford, Department of Experimental Psychology, Oxford (United Kingdom); Wenderoth, Nicole [ETH Zurich, Neural Control of Movement Laboratory, Department of Health Sciences and Technology, Zurich (Switzerland); KU Leuven, Laboratory of Movement Control and Neuroplasticity, Faculty of Kinesiology and Rehabilitation Sciences, Leuven (Belgium)

    2015-09-15

    A workflow based on the ratio between standardized T1-weighted (T1-w) and T2-weighted (T2-w) MR images has been proposed as a new tool to study brain structure. This approach was previously used to map structural properties in the healthy brain. Here, we evaluate whether the T1-w/T2-w approach can support the assessment of structural impairments in the diseased brain. We use schizophrenia data to demonstrate the potential clinical utility of the technique. We analyzed T1-w and T2-w images of 36 schizophrenic patients and 35 age-matched controls. These were collected for the Function Biomedical Informatics Research Network (fBIRN) collaborative project, which had an IRB approval and followed the HIPAA guidelines. We computed T1-w/T2-w images for each individual and compared intensities in schizophrenic and control groups on a voxel-wise basis, as well as in regions of interest (ROIs). Our results revealed that the T1-w/T2-w image permits to discriminate brain regions showing group-level differences between patients and controls with greater accuracy than conventional T1-w and T2-w images. Both the ROIs and the voxel-wise analysis showed globally reduced gray and white matter values in patients compared to controls. Significantly reduced values were found in regions such as insula, primary auditory cortex, hippocampus, inferior longitudinal fasciculus, and inferior fronto-occipital fasciculus. Our findings were consistent with previous meta-analyses in schizophrenia corroborating the hypothesis of a potential ''disconnection'' syndrome in conjunction with structural alterations in local gray matter regions. Overall, our study suggested that the T1-w/T2-w technique permits to reliably map structural differences between the brains of patients and healthy individuals. (orig.)

  20. Whole-brain analytic measures of network communication reveal increased structure-function correlation in right temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Jonathan Wirsich

    2016-01-01

    In rTLE patients, we found a widespread hypercorrelated functional network. Network communication analysis revealed greater unspecific branching of the shortest path (search information in the structural connectome and a higher global correlation between the structural and functional connectivity for the patient group. We also found evidence for a preserved structural rich-club in the patient group. In sum, global augmentation of structure-function correlation might be linked to a smaller functional repertoire in rTLE patients, while sparing the central core of the brain which may represent a pathway that facilitates the spread of seizures.