Sample records for brain hemispheric differences

  1. Right Hemisphere Brain Damage (United States)

    ... or hemispheres. Each hemisphere is responsible for different body functions and skills. In most people, the left side of the brain contains the person's language functions. The right side contributes to a number ...

  2. Brain Hemisphericity and Developmental Dyslexia (United States)

    Vlachos, Filippos; Andreou, Eleni; Delliou, Afroditi


    The present study examined the link between brain hemisphericity and dyslexia in secondary school students, using the Preference Test (PT), a widely used self-report index of preferred hemisphere thinking styles. The hypothesis was that differences would be revealed between the dyslexic group and their peers in hemispheric preference. A total of…

  3. Hemisphere- and gender-related differences in small-world brain networks: a resting-state functional MRI study. (United States)

    Tian, Lixia; Wang, Jinhui; Yan, Chaogan; He, Yong


    We employed resting-state functional MRI (R-fMRI) to investigate hemisphere- and gender-related differences in the topological organization of human brain functional networks. Brain networks were first constructed by measuring inter-regional temporal correlations of R-fMRI data within each hemisphere in 86 young, healthy, right-handed adults (38 males and 48 females) followed by a graph-theory analysis. The hemispheric networks exhibit small-world attributes (high clustering and short paths) that are compatible with previous results in the whole-brain functional networks. Furthermore, we found that compared with females, males have a higher normalized clustering coefficient in the right hemispheric network but a lower clustering coefficient in the left hemispheric network, suggesting a gender-hemisphere interaction. Moreover, we observed significant hemisphere-related differences in the regional nodal characteristics in various brain regions, such as the frontal and occipital regions (leftward asymmetry) and the temporal regions (rightward asymmetry), findings that are consistent with previous studies of brain structural and functional asymmetries. Together, our results suggest that the topological organization of human brain functional networks is associated with gender and hemispheres, and they provide insights into the understanding of functional substrates underlying individual differences in behaviors and cognition.

  4. A novel extended Granger Causal Model approach demonstrates brain hemispheric differences during face recognition learning.

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    Tian Ge


    Full Text Available Two main approaches in exploring causal relationships in biological systems using time-series data are the application of Dynamic Causal model (DCM and Granger Causal model (GCM. These have been extensively applied to brain imaging data and are also readily applicable to a wide range of temporal changes involving genes, proteins or metabolic pathways. However, these two approaches have always been considered to be radically different from each other and therefore used independently. Here we present a novel approach which is an extension of Granger Causal model and also shares the features of the bilinear approximation of Dynamic Causal model. We have first tested the efficacy of the extended GCM by applying it extensively in toy models in both time and frequency domains and then applied it to local field potential recording data collected from in vivo multi-electrode array experiments. We demonstrate face discrimination learning-induced changes in inter- and intra-hemispheric connectivity and in the hemispheric predominance of theta and gamma frequency oscillations in sheep inferotemporal cortex. The results provide the first evidence for connectivity changes between and within left and right inferotemporal cortexes as a result of face recognition learning.

  5. Age, gender, and hemispheric differences in iron deposition in the human brain: an in vivo MRI study. (United States)

    Xu, Xiaojun; Wang, Qidong; Zhang, Minming


    It is well known that iron accumulates in the brains of patients with various neurodegenerative diseases. To better understand disease-related iron changes, it is necessary to know the physiological distribution and accumulation of iron in the human brain. Studies have shown that brain iron levels increase with aging. However, the effects of gender and hemispheric laterality on iron accumulation and distribution are not well established. In this study, we estimated the brain iron levels in vivo in 78 healthy adults ranging in age 22 to 78 years using magnetic susceptibility-weighted phase imaging. The effects of age, gender, and hemispheric location on brain iron levels were evaluated within the framework of a general linear model. We found that the left hemisphere had higher iron levels than the right in the putamen, globus pallidus, substantia nigra, thalamus, and frontal white matter. We argue that the hemispheric asymmetry of iron content may underlie that of the dopaminergic system and may be related to motor lateralization in humans. In addition, significant age-related iron accumulation occurred in the putamen, red nucleus, and frontal white matter, but no gender-related differences in iron levels were detected. The results of this study extend our knowledge of the physiological distribution and accumulation of iron in the human brain.

  6. A different story on "Theory of Mind" deficit in adults with right hemisphere brain damage. (United States)

    Tompkins, Connie A; Scharp, Victoria L; Fassbinder, Wiltrud; Meigh, Kimberly M; Armstrong, Elizabeth M


    BACKGROUND: Difficulties in social cognition and interaction can characterise adults with unilateral right hemisphere brain damage (RHD). Some pertinent evidence involves their apparently poor reasoning from a "Theory of Mind" perspective, which requires a capacity to attribute thoughts, beliefs, and intentions in order to understand other people's behaviour. Theory of Mind is typically assessed with tasks that induce conflicting mental representations. Prior research with a commonly used text task reported that adults with RHD were less accurate in drawing causal inferences about mental states than at making non-mental-state causal inferences from control texts. However, the Theory of Mind and control texts differed in the number and nature of competing discourse entity representations. This stimulus discrepancy, together with the explicit measure of causal inferencing, likely put the adults with RHD at a disadvantage on the Theory of Mind texts. AIMS: This study revisited the question of Theory of Mind deficit in adults with RHD. The aforementioned Theory of Mind texts were used but new control texts were written to address stimulus discrepancies, and causal inferencing was assessed relatively implicitly. Adults with RHD were hypothesised not to display a Theory of Mind deficit under these conditions. METHODS #ENTITYSTARTX00026; PROCEDURES: The participants were 22 adults with unilateral RHD from cerebrovascular accident, and 38 adults without brain damage. Participants listened to spoken texts that targeted either mental-state or non-mental-state causal inferences. Each text was followed by spoken True/False probe sentences, to gauge target inference comprehension. Both accuracy and RT data were recorded. Data were analysed with mixed, two-way Analyses of Variance (Group by Text Type). OUTCOMES #ENTITYSTARTX00026; RESULTS: There was a main effect of Text Type in both accuracy and RT analyses, with a performance advantage for the Theory of Mind

  7. Gender differences in functional hemispheric asymmetry during processing of vowels as reflected by the human brain magnetic response. (United States)

    Obleser, J; Eulitz, C; Lahiri, A; Elbert, T


    A number of findings indicate gender differences in language-related functional hemispheric brain asymmetry. To test if such gender-specific laterality is already present at the level of vowel-processing, the auditory evoked magnetic field was recorded in healthy right-handed male and female participants in response to the German synthetic vowels [a], [e] and [i]. Female participants exhibited stronger N100m responses than male participants over the left hemisphere. This observation was highly reliable across repeated experimental sessions. The present lateralization shows that previous findings suggesting a stronger left-hemispheric dominance for verbal material in males than in females can not be generalized to basic speech elements. Furthermore, the present results support the importance of controlling for gender ratio in studies of phonetic processing.

  8. A different story on “Theory of Mind” deficit in adults with right hemisphere brain damage (United States)

    Tompkins, Connie A.; Scharp, Victoria L.; Fassbinder, Wiltrud; Meigh, Kimberly M.; Armstrong, Elizabeth M.


    Background Difficulties in social cognition and interaction can characterise adults with unilateral right hemisphere brain damage (RHD). Some pertinent evidence involves their apparently poor reasoning from a “Theory of Mind” perspective, which requires a capacity to attribute thoughts, beliefs, and intentions in order to understand other people’s behaviour. Theory of Mind is typically assessed with tasks that induce conflicting mental representations. Prior research with a commonly used text task reported that adults with RHD were less accurate in drawing causal inferences about mental states than at making non-mental-state causal inferences from control texts. However, the Theory of Mind and control texts differed in the number and nature of competing discourse entity representations. This stimulus discrepancy, together with the explicit measure of causal inferencing, likely put the adults with RHD at a disadvantage on the Theory of Mind texts. Aims This study revisited the question of Theory of Mind deficit in adults with RHD. The aforementioned Theory of Mind texts were used but new control texts were written to address stimulus discrepancies, and causal inferencing was assessed relatively implicitly. Adults with RHD were hypothesised not to display a Theory of Mind deficit under these conditions. Methods & Procedures The participants were 22 adults with unilateral RHD from cerebrovascular accident, and 38 adults without brain damage. Participants listened to spoken texts that targeted either mental-state or non-mental-state causal inferences. Each text was followed by spoken True/False probe sentences, to gauge target inference comprehension. Both accuracy and RT data were recorded. Data were analysed with mixed, two-way Analyses of Variance (Group by Text Type). Outcomes & Results There was a main effect of Text Type in both accuracy and RT analyses, with a performance advantage for the Theory of Mind/mental-state inference stimuli. The control group

  9. The calculating hemispheres: studies of a split-brain patient. (United States)

    Funnell, Margaret G; Colvin, Mary K; Gazzaniga, Michael S


    The purpose of the study was to investigate simple calculation in the two cerebral hemispheres of a split-brain patient. In a series of four experiments, the left hemisphere was superior to the right in simple calculation, confirming the previously reported left hemisphere specialization for calculation. In two different recognition paradigms, right hemisphere performance was at chance for all arithmetic operations, with the exception of subtraction in a two-alternative forced choice paradigm (performance was at chance when the lure differed from the correct answer by a magnitude of 1 but above chance when the magnitude difference was 4). In a recall paradigm, the right hemisphere performed above chance for both addition and subtraction, but performed at chance levels for multiplication and division. The error patterns in that experiment suggested that for subtraction and addition, the right hemisphere does have some capacity for approximating the solution even when it is unable to generate the exact solution. Furthermore, right hemisphere accuracy in addition and subtraction was higher for problems with small operands than with large operands. An additional experiment assessed approximate and exact addition in the two hemispheres for problems with small and large operands. The left hemisphere was equally accurate in both tasks but the right hemisphere was more accurate in approximate addition than in exact addition. In exact addition, right hemisphere accuracy was higher for problems with small operands than large, but the opposite pattern was found for approximate addition.


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    T. Ya. Abramova


    Full Text Available Abstract. Possible interactions between psychophysiological and immunological parameters are documented in healthy persons and bronchial asthma patients, as based on our own data and other sources. A role of functional asymmetry of brain is regarded as a basic phenomenon determining main features of psychical activity, as well as functions of autonomous nervous system and immunological activity.

  11. Chorus from Two Brain Hemispheres with Chinese Pentatonic Scale

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    WU Dan; YAO De-zhong


    In order to listen to brain activity as a piece of music, we proposed a scale-free brainwave music (SFBM) technology, which translates the scalp EEG into music notes according to the power law of both EEG and music. In this paper, the methodology was further extended to chorus music of two channels from the two hemispheres. Firstly, EEG data from two channels symmetrically located on the left and right hemispheres are translated into MIDI sequences by SFBM, respectively, where the EEG parameters modulate the pitch, duration and volume of each music note. Then, the two sequences are fiitered into a chorus of the Chinese pentatonic scale or the Western major scale. The resulted Chinese and Western music at different sleep stages illustrate distinct differences in harmony, and the music with Chinese pentatonic scale sounds more harmonious.

  12. Lateralized Difference in Tympanic Membrane Temperature: Emotion and Hemispheric Activity

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    Ruth E Propper


    Full Text Available We review literature examining relationships between tympanic membrane temperature (TMT, affective/motivational orientation, and hemispheric activity. Lateralized differences in TMT might enable real-time monitoring of hemispheric activity in real-world conditions, and could serve as a corroborating marker of mental illnesses associated with specific affective dysregulation. We support the proposal that TMT holds potential for broadly indexing lateralized brain physiology during tasks demanding the processing and representation of emotional and/or motivational states, and for predicting trait-related affective/motivational orientations. The precise nature of the relationship between TMT and brain physiology, however, remains elusive. Indeed the limited extant research has sampled different participant populations and employed largely different procedures and measures, making for seemingly discrepant findings and implications. We propose, however, that many of these discrepancies can be resolved by considering how emotional states map onto motivational systems, and further examining how validated methods for inducing lateralized brain activity might affect TMT.

  13. Hemispheric asymmetry of electroencephalography-based functional brain networks. (United States)

    Jalili, Mahdi


    Electroencephalography (EEG)-based functional brain networks have been investigated frequently in health and disease. It has been shown that a number of graph theory metrics are disrupted in brain disorders. EEG-based brain networks are often studied in the whole-brain framework, where all the nodes are grouped into a single network. In this study, we studied the brain networks in two hemispheres and assessed whether there are any hemispheric-specific patterns in the properties of the networks. To this end, resting state closed-eyes EEGs from 44 healthy individuals were processed and the network structures were extracted separately for each hemisphere. We examined neurophysiologically meaningful graph theory metrics: global and local efficiency measures. The global efficiency did not show any hemispheric asymmetry, whereas the local connectivity showed rightward asymmetry for a range of intermediate density values for the constructed networks. Furthermore, the age of the participants showed significant direct correlations with the global efficiency of the left hemisphere, but only in the right hemisphere, with local connectivity. These results suggest that only local connectivity of EEG-based functional networks is associated with brain hemispheres.

  14. Hemispherical dominance of glucose metabolic rate in the brain of the 'normal' ageing population

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    Cutts, DA; Maguire, RP; Leenders, KL; Spyrou, NM


    In the 'normal' ageing brain a decrease in the cerebral metabolic rate has been determined across many brain regions. This study determines whether age differences would affect metabolic rates in regions and different hemispheres of the brain. The regional metabolic rate of glucose (rCMRGlu) was exa

  15. The Brain's Hemispheres and Controlled Search of the Lexicon: Evidence from Fixated Words and Pseudowords (United States)

    Rutherford, Barbara J.; Mathesius, Jeffrey R.


    Difference between the brain's hemispheres in efficiency of intentional search of the mental lexicon with phonological, orthographic, and semantic strategies was investigated. Letter strings for lexical decision were presented at fixation, with a lateralized distractor to the LVF or RVF. Word results revealed that both hemispheres were capable of…

  16. Genetic biomarkers for brain hemisphere differentiation in Parkinson's Disease (United States)

    Hourani, Mou'ath; Mendes, Alexandre; Berretta, Regina; Moscato, Pablo


    This work presents a study on the genetic profile of the left and right hemispheres of the brain of a mouse model of Parkinson's disease (PD). The goal is to characterize, in a genetic basis, PD as a disease that affects these two brain regions in different ways. Using the same whole-genome microarray expression data introduced by Brown et al. (2002) [1], we could find significant differences in the expression of some key genes, well-known to be involved in the mechanisms of dopamine production control and PD. The problem of selecting such genes was modeled as the MIN (α,β)—FEATURE SET problem [2]; a similar approach to that employed previously to find biomarkers for different types of cancer using gene expression microarray data [3]. The Feature Selection method produced a series of genetic signatures for PD, with distinct expression profiles in the Parkinson's model and control mice experiments. In addition, a close examination of the genes composing those signatures shows that many of them belong to genetic pathways or have ontology annotations considered to be involved in the onset and development of PD. Such elements could provide new clues on which mechanisms are implicated in hemisphere differentiation in PD.


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    Bünyamin Sahin


    Full Text Available It is well known that there are functional differences between right and left brain hemispheres. However, it is not clear whether these functional differences are reflected in morphometric differences. This study was carried out to investigate the right-left asymmetry, and sex and species differences of the brains using the Cavalieri principle for volume estimation. Seventeen lambs, 10 rats and 12 avian brains were used to estimate brain volumes. A transparent point grid was superimposed on the slices of lamb brains directly and the slices of the rat and avian brains were projected onto a screen at 10x magnification. Surface areas of the cut slice faces were estimated by simply counting the points that hit the slices. Mean brain volumes were 37.74 cm3, 598.95 mm3 and 730.38 mm3 and the coefficients of variations were 0.08, 0.05 and 0.05 for lamb, rat and avian brains respectively. The differences between left and right hemispheres did not show statistical significance (P > 0.05. However, the male brain volumes were larger than the females for the lamb and bird (P < 0.05. In light of such findings, it will be necessary to evaluate neuron number of the brain hemispheres to provide more useful data regarding inter-hemispheric brain asymmetry.

  18. Effects of mental rotation on acalculia: differences in the direction of mental rotation account for the differing characteristics of acalculia induced by right and left hemispheric brain injury. (United States)

    Asada, Tomohiko; Takayama, Yoshihiro; Oita, Jiro; Fukuyama, Hidenao


    We observed a 59-year-old right-handed man with an infarction in his right-middle cerebral artery that included the parietal lobe, who abnormally manipulated mental images in the horizontal direction, resulting in calculation disturbances. Three years later, the patient suffered an infarction in the left parietal lobe and displayed abnormalities during the creation of mental images; i.e., he rotated them in the vertical direction, which again resulted in calculation disturbances. These mental imagery disturbances might indicate that a common acalculia mechanism exists between the right and left hemispheres.

  19. Brain hemisphere dominance and vocational preference: a preliminary analysis. (United States)

    Szirony, Gary Michael; Pearson, L Carolyn; Burgin, John S; Murray, Gerald C; Elrod, Lisa Marie


    Recent developments in split-brain theory add support to the concept of specialization within brain hemispheres. Holland's vocational personality theory may overlap with Human Information Processing (HIP) characteristics. Holland's six RIASEC codes were developed to identify vocational personality characteristics, and HIP scales were designed to measure hemispheric laterality. Relationships between the two scales were evaluated through canonical correlation with some significant results, however not all Holland scale scores correlated with left, right, or integrated hemispheric preference. Additional findings related to participants self-perception of music and math ability were also correlated. Findings on this added analysis revealed a high correlation between perception of musical ability and right brain function but not between mathematical concept and left brain alone. Implications regarding vocational choice and work are discussed.

  20. Detection of spatial frequency in brain-damaged patients: influence of hemispheric asymmetries and hemineglect

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    Natanael Antonio Dos Santos


    Full Text Available Hemispheric specialization for spatial frequency processing was investigated by measuring the contrast sensitivity curves of sine-wave gratings in 30 left or right brain-damaged patients using different spatial frequencies compared with healthy participants. The results showed that left brain-damaged patients were selectively impaired in processing high frequencies, whereas right brain-damaged patients were more impaired in the processing low frequencies, regardless of the presence of visuo-spatial neglect. These visual processing results can be interpreted in terms of spatial frequency discrimination, with both hemispheres participating in this process in different ways.

  1. Brain Hemispheric Consensus and the Quality of Investment Decisions. (United States)

    Boyd, Michael

    This on-going study explores the hypothesis that stock fund managers who underperform do so because they make bad decisions, and examines whether their choices can be improved by using a decision model that invokes principles of brain hemispheric consensus. The study, begun in fall 1999, involves two groups of business students: the control group…

  2. Gender differences in hemispheric asymmetry for face processing

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    Matarazzo Silvia


    Full Text Available Abstract Background Current cognitive neuroscience models predict a right-hemispheric dominance for face processing in humans. However, neuroimaging and electromagnetic data in the literature provide conflicting evidence of a right-sided brain asymmetry for decoding the structural properties of faces. The purpose of this study was to investigate whether this inconsistency might be due to gender differences in hemispheric asymmetry. Results In this study, event-related brain potentials (ERPs were recorded in 40 healthy, strictly right-handed individuals (20 women and 20 men while they observed infants' faces expressing a variety of emotions. Early face-sensitive P1 and N1 responses to neutral vs. affective expressions were measured over the occipital/temporal cortices, and the responses were analyzed according to viewer gender. Along with a strong right hemispheric dominance for men, the results showed a lack of asymmetry for face processing in the amplitude of the occipito-temporal N1 response in women to both neutral and affective faces. Conclusion Men showed an asymmetric functioning of visual cortex while decoding faces and expressions, whereas women showed a more bilateral functioning. These results indicate the importance of gender effects in the lateralization of the occipito-temporal response during the processing of face identity, structure, familiarity, or affective content.

  3. The "consonance effect" and the hemispheres: a study on a split-brain patient. (United States)

    Prete, Giulia; Fabri, Mara; Foschi, Nicoletta; Brancucci, Alfredo; Tommasi, Luca


    The association between musical consonance and pleasantness, and between musical dissonance and unpleasantness ("consonance effect") is well established. Furthermore, a number of studies suggest the main involvement of the left hemisphere in the perception of dissonance and that of the right hemisphere in the perception of consonance. In the present study, the consonance effect was studied in a callosotomized patient, D. D. C. and in a control group. In binaural presentations, the patient did not attribute different pleasantness judgements to consonant and dissonant chords, differently from the control group who showed the consonance effect. However, in dichotic presentations (e.g. a chord in one ear and white noise in the other ear), a trend towards the consonance effect was found in D. D. C., but only when chords were presented in his right ear (left hemisphere), whereas the control group confirmed the known hemispheric asymmetry in labelling the pleasantness of consonant and dissonant chords. These results suggest that the right-hemispheric superiority in appreciating consonance might hide the inability of the right hemisphere to classify dissonant chords as unpleasant in the split-brain, whereas the left hemisphere seems capable to differently label the pleasantness of consonant and dissonant chords, even if it is more sensitive to dissonance.

  4. Hemispheric Asymmetry of Human Brain Anatomical Network Revealed by Diffusion Tensor Tractography. (United States)

    Shu, Ni; Liu, Yaou; Duan, Yunyun; Li, Kuncheng


    The topological architecture of the cerebral anatomical network reflects the structural organization of the human brain. Recently, topological measures based on graph theory have provided new approaches for quantifying large-scale anatomical networks. However, few studies have investigated the hemispheric asymmetries of the human brain from the perspective of the network model, and little is known about the asymmetries of the connection patterns of brain regions, which may reflect the functional integration and interaction between different regions. Here, we utilized diffusion tensor imaging to construct binary anatomical networks for 72 right-handed healthy adult subjects. We established the existence of structural connections between any pair of the 90 cortical and subcortical regions using deterministic tractography. To investigate the hemispheric asymmetries of the brain, statistical analyses were performed to reveal the brain regions with significant differences between bilateral topological properties, such as degree of connectivity, characteristic path length, and betweenness centrality. Furthermore, local structural connections were also investigated to examine the local asymmetries of some specific white matter tracts. From the perspective of both the global and local connection patterns, we identified the brain regions with hemispheric asymmetries. Combined with the previous studies, we suggested that the topological asymmetries in the anatomical network may reflect the functional lateralization of the human brain.

  5. Hemispheric Asymmetry of Human Brain Anatomical Network Revealed by Diffusion Tensor Tractography

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    Ni Shu


    Full Text Available The topological architecture of the cerebral anatomical network reflects the structural organization of the human brain. Recently, topological measures based on graph theory have provided new approaches for quantifying large-scale anatomical networks. However, few studies have investigated the hemispheric asymmetries of the human brain from the perspective of the network model, and little is known about the asymmetries of the connection patterns of brain regions, which may reflect the functional integration and interaction between different regions. Here, we utilized diffusion tensor imaging to construct binary anatomical networks for 72 right-handed healthy adult subjects. We established the existence of structural connections between any pair of the 90 cortical and subcortical regions using deterministic tractography. To investigate the hemispheric asymmetries of the brain, statistical analyses were performed to reveal the brain regions with significant differences between bilateral topological properties, such as degree of connectivity, characteristic path length, and betweenness centrality. Furthermore, local structural connections were also investigated to examine the local asymmetries of some specific white matter tracts. From the perspective of both the global and local connection patterns, we identified the brain regions with hemispheric asymmetries. Combined with the previous studies, we suggested that the topological asymmetries in the anatomical network may reflect the functional lateralization of the human brain.

  6. Hemispheric asymmetry of the brain as a psycho-physiological basis of individual and typological features of the formation of a sense of humour

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    Shportun O.N.


    Full Text Available The article describes the psycho-physiological peculiarities of hemispheric asymmetry of the brain as the basis of individual and typological features of the formation of a sense of humour. The analysis of the impact of the functional brain hemispheric asymmetry on emotional, intellectual and physiological features of development of sense of humour in ontogeny is conducted. Analysis of studies of inter-hemispheric asymmetry of the brain makes it possible to ascertain the impact of the functioning of each hemisphere on the formation of the perception of humour. Studies show that in the process of developing of sense of humour, two functional hemispheres of the brain are involved. As the emotion of humour – is an intellectual emotion, and in the development of intelligence a lot of mental processes are involved, in the formation of humour two hemispheres of the brain are functioned. The right hemisphere is responsible for the emotional nature of humour (intonation, sound level of language, speed of response to a joke ..., the left hemisphere – for processing verbal information (content of the joke, category, purpose, content analysis .... After analysing the research of hemispheric functional asymmetry of the human brain, its psycho-physiological and neurochemical characteristics, it can be assumed that people with more developed left hemisphere in perceiving humour are more prone to displays of gelotophilia and “right hemisphere” people – show signs of gelotophobia and katagelasticism. Examining gender differences of hemisphere asymmetry of the brain, it can be argued that diagnosing sense of humour is important to take into account gender-specific functioning of hemispheres, because men have more clearly functioning the left hemisphere, and women – the right one. This fact of sexual peculiarities of functioning of inter-hemispheric asymmetry of the brain allows diagnosing objectively sense of humour, as well as different variations

  7. Individual differences in hemispheric preference and emotion regulation difficulties

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    Garima Gupta


    Full Text Available Background: Hemisphericity or individual difference in the preference to use the left or the right hemispheric mode of information processing has been associated with various emotion-related differences. For example, the right hemisphericity has been linked with inhibition of emotional expression, feeling of tension, greater impulsivity etc. These observations suggest that right hemisphericity may be associated with greater difficulties in regulating emotions. However, direct empirical tests of such theoretical proposition are very thin. Aim: In view of this, the present study aims to investigate how and to what extent individual difference in hemispheric preference relate to emotion regulation. Materials and Methods: Thirty-two right-handed male subjects in the age range 18 to 20 years were assessed on self-report measures of hemispheric preference and emotion regulation difficulties. The correlation between dimensions of hemispheric preference and difficulties in regulating emotions was computed. A series of stepwise multiple regression analyses were also done to explore the relative significance of various dimensions of hemispheric preference in predicting emotion regulation difficulties. Results: The findings revealed that in general a preference for the right hemispheric mode of information processing was associated with greater emotion regulation difficulties. The correlation analysis indicated that while impulse control difficulties and difficulties in engaging goal directed behavior was associated with preference for almost all the right hemispheric mode of information processing, the nonacceptance of emotional responses and limited access to emotion regulation was related to preference for only global/synthetic (a right hemispheric mode of information processing. Similarly, the lack of emotional clarity facet of emotion regulation difficulties correlated significantly with a preference for the emotional mode of information processing

  8. Three-dimensional X-ray visualization of axonal tracts in mouse brain hemisphere

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    Mizutani, Ryuta; Ohtsuka, Masato; Miura, Hiromi; Hoshino, Masato; Takeuchi, Akihisa; Uesugi, Kentaro


    Neurons transmit active potentials through axons, which are essential for the brain to function. In this study, the axonal networks of the murine brain were visualized with X-ray tomographic microscopy, also known as X-ray microtomography or micro-CT. Murine brain samples were freeze-dried to reconstitute the intrinsic contrast of tissue constituents and subjected to X-ray visualization. A whole brain hemisphere visualized by absorption contrast illustrated three-dimensional structures including those of the striatum, corpus callosum, and anterior commissure. Axonal tracts observed in the striatum start from the basal surface of the cerebral cortex and end at various positions in the basal ganglia. The distribution of X-ray attenuation coefficients indicated that differences in water and phospholipid content between the myelin sheath and surrounding tissue constituents account for the observed contrast. A rod-shaped cutout of brain tissue was also analyzed with a phase retrieval method, wherein tissue microst...

  9. Diffusion tensor imaging of hemispheric asymmetries in the developing brain. (United States)

    Wilde, Elisabeth A; McCauley, Stephen R; Chu, Zili; Hunter, Jill V; Bigler, Erin D; Yallampalli, Ragini; Wang, Zhiyue J; Hanten, Gerri; Li, Xiaoqi; Ramos, Marco A; Sabir, Sharjeel H; Vasquez, Ana C; Menefee, Deleene; Levin, Harvey S


    Diffusion tensor imaging (DTI) was performed in 39 right-handed children to examine structural hemispheric differences and the impact of age, socioeconomic status, and sex on these differences. Apparent diffusion coefficient (ADC) values were smaller in the left than in the right temporal, prefrontal, anterior internal capsular and the thalamic regions, and fractional anisotropy (FA) values were larger in the left than in the right internal capsule, thalamus, and cingulate. Significant region-by-sex interactions disclosed that the relation of DTI asymmetries to performance depended on sex including the relation of temporal lobes to reading comprehension and the relation of frontal lobes to solving applied mathematical problems.

  10. Cortical projection topography of the human splenium: hemispheric asymmetry and individual differences. (United States)

    Putnam, Mary Colvin; Steven, Megan S; Doron, Karl W; Riggall, Adam C; Gazzaniga, Michael S


    The corpus callosum is the largest white matter pathway in the human brain. The most posterior portion, known as the splenium, is critical for interhemispheric communication between visual areas. The current study employed diffusion tensor imaging to delineate the complete cortical projection topography of the human splenium. Homotopic and heterotopic connections were revealed between the splenium and the posterior visual areas, including the occipital and the posterior parietal cortices. In nearly one third of participants, there were homotopic connections between the primary visual cortices, suggesting interindividual differences in splenial connectivity. There were also more instances of connections with the right hemisphere, indicating a hemispheric asymmetry in interhemispheric connectivity within the splenium. Combined, these findings demonstrate unique aspects of human interhemispheric connectivity and provide anatomical bases for hemispheric asymmetries in visual processing and a long-described hemispheric asymmetry in speed of interhemispheric communication for visual information.

  11. Reduced Hemispheric Asymmetry of Brain Anatomical Networks Is Linked to Schizophrenia: A Connectome Study. (United States)

    Sun, Yu; Chen, Yu; Collinson, Simon L; Bezerianos, Anastasios; Sim, Kang


    Despite convergent evidence indicating a variety of regional abnormalities of hemispheric asymmetry in schizophrenia, patterns of wider neural network asymmetry remain to be determined. In this study, we investigated alterations in hemispheric white matter topology in schizophrenia and their association with clinical manifestations of the illness. Weighted hemispheric brain anatomical networks were constructed for each of 116 right-handed patients with schizophrenia and 66 matched healthy participants. Graph theoretical approaches were then employed to estimate the hemispheric topological properties. We found that although small-world properties were preserved in the hemispheric network, a significant hemispheric-independent deficit of global integration was found in schizophrenia. Furthermore, a significant group-by-hemisphere interaction was revealed in the characteristic path length and global efficiency, attributing to significantly reduced hemispheric asymmetry of global integration in patients compared with healthy controls. Specifically, we found reduced asymmetric nodal efficiency in several frontal regions and the hippocampus. Finally, the abnormal hemispheric asymmetry of brain anatomical network topology was associated with clinical features (duration of illness and psychotic psychopathology) in patients. Our findings provide new insights into lateralized nature of hemispheric dysconnectivity and highlight the potential for using brain network measures of hemispheric asymmetry as neural biomarkers for schizophrenia and its clinical features.

  12. Role of inter-hemispheric transfer in generating visual evoked potentials in V1-damaged brain hemispheres. (United States)

    Kavcic, Voyko; Triplett, Regina L; Das, Anasuya; Martin, Tim; Huxlin, Krystel R


    Partial cortical blindness is a visual deficit caused by unilateral damage to the primary visual cortex, a condition previously considered beyond hopes of rehabilitation. However, recent data demonstrate that patients may recover both simple and global motion discrimination following intensive training in their blind field. The present experiments characterized motion-induced neural activity of cortically blind (CB) subjects prior to the onset of visual rehabilitation. This was done to provide information about visual processing capabilities available to mediate training-induced visual improvements. Visual Evoked Potentials (VEPs) were recorded from two experimental groups consisting of 9 CB subjects and 9 age-matched, visually-intact controls. VEPs were collected following lateralized stimulus presentation to each of the 4 visual field quadrants. VEP waveforms were examined for both stimulus-onset (SO) and motion-onset (MO) related components in postero-lateral electrodes. While stimulus presentation to intact regions of the visual field elicited normal SO-P1, SO-N1, SO-P2 and MO-N2 amplitudes and latencies in contralateral brain regions of CB subjects, these components were not observed contralateral to stimulus presentation in blind quadrants of the visual field. In damaged brain hemispheres, SO-VEPs were only recorded following stimulus presentation to intact visual field quadrants, via inter-hemispheric transfer. MO-VEPs were only recorded from damaged left brain hemispheres, possibly reflecting a native left/right asymmetry in inter-hemispheric connections. The present findings suggest that damaged brain hemispheres contain areas capable of responding to visual stimulation. However, in the absence of training or rehabilitation, these areas only generate detectable VEPs in response to stimulation of the intact hemifield of vision.

  13. Regional protein synthesis in rat brain following acute hemispheric ischemia. (United States)

    Dienel, G A; Pulsinelli, W A; Duffy, T E


    Regional protein synthesis was measured in rat brain at intervals up to 48 h following occlusion of the four major arteries to the brain for either 10 or 30 min. Four-vessel occlusions produces ischemia in the cerebral hemispheres and oligemia in the midbrain-diencephalon and brainstem. During the hour following 10 min of ischemia, protein synthesis, measured by incorporation of [14C]valine into protein, was inhibited in the cerebral cortex by 67%. Normal rates of protein synthesis were attained within 4 h of recirculation. In rats subjected to 30 min of ischemia, protein synthesis was inhibited by 83% during the first hour of recirculation in the cortex, caudate-putamen, and hippocampus. Recovery of protein synthesis in these regions was slow (25-48 h). The midbrain-diencephalon showed less inhibition, 67%, and faster recovery (by 12 h). Protein synthesis was unaffected in the brainstem. [14C]Autoradiography revealed that the pyramidal neurons of the hippocampus and areas of the caudate and cortex failed to recover normal rates of protein synthesis even after 48 h. The accumulation of TCA-soluble [14C]valine was enhanced (55-65%) in the cortex, caudate, and hippocampus after 30 min of ischemia; the increase persisted for 12 h. A smaller rise in [14C]valine content (30%) and more rapid normalization of valine accumulation (by 7 h) were observed in the midbrain-diencephalon; no changes were found in the brainstem. In the cortex, recovery was more rapid when the duration of ischemia was reduced. Thus, the degree of inhibition of protein synthesis, the accumulation of valine in the tissue, and the length of time required to reestablish normal values for these processes were dependent on both the severity and the duration of the ischemic insult. Restoration of normal rates of protein synthesis after ischemia was slow compared with the normalization of cerebral energy metabolites.

  14. Secular variation of hemispheric phase differences in the solar cycle

    CERN Document Server

    Zolotova, N V; Arlt, R; Tuominen, I


    We investigate the phase difference of the sunspot cycles in the two hemispheres and compare it with the latitudinal sunspot distribution. If the north-south phase difference exhibits a long-term tendency, it should not be regarded as a stochastic phenomenon. We use datasets of historical sunspot records and drawings made by Staudacher, Hamilton, Gimingham, Carrington, Spouml;rer, and Greenwich observers, as well as the sunspot activity during the Maunder minimum reconstructed by Ribes and Nesme-Ribes. We employ cross-recurrence plots to analyse north-south phase differences. We show that during the last 300 years, the persistence of phase-leading in one of the hemispheres exhibits a secular variation. Changes from one hemisphere to the other leading in phase were registered near 1928 and 1968 as well as two historical ones near 1783 and 1875. A long-term anticorrelation between the hemispheric phase differences in the sunspot cycles and the latitudinal distribution of sunspots was traced since 1750.

  15. Hemispheric speech lateralisation in the developing brain is related to motor praxis ability

    Directory of Open Access Journals (Sweden)

    Jessica C. Hodgson


    Full Text Available Commonly displayed functional asymmetries such as hand dominance and hemispheric speech lateralisation are well researched in adults. However there is debate about when such functions become lateralised in the typically developing brain. This study examined whether patterns of speech laterality and hand dominance were related and whether they varied with age in typically developing children. 148 children aged 3–10 years performed an electronic pegboard task to determine hand dominance; a subset of 38 of these children also underwent functional Transcranial Doppler (fTCD imaging to derive a lateralisation index (LI for hemispheric activation during speech production using an animation description paradigm. There was no main effect of age in the speech laterality scores, however, younger children showed a greater difference in performance between their hands on the motor task. Furthermore, this between-hand performance difference significantly interacted with direction of speech laterality, with a smaller between-hand difference relating to increased left hemisphere activation. This data shows that both handedness and speech lateralisation appear relatively determined by age 3, but that atypical cerebral lateralisation is linked to greater performance differences in hand skill, irrespective of age. Results are discussed in terms of the common neural systems underpinning handedness and speech lateralisation.

  16. Opposed Left and Right Brain Hemisphere Contributions to Sexual Drive: A Multiple Lesion Case Analysis

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    Claude M. J. Braun


    Full Text Available Brain topographical studies of normal men have have shown that sexual excitation is asymmetric in the brain hemispheres. Group studies of patients with unilateral epileptic foci and other studies of patients with unilateral brain lesions have come to the same conclusion. The present study reviewed previously published single case reports of patients with frank hypo or hypersexuality subsequent to a unilateral brain lesion. Hyposexual patients tended to have left hemisphere lesions (primarily of the temporal lobe, and hypersexual patients tended to have right hemisphere lesions (primarily of the temporal lobe (p < 0.05. We interpret this double dissociation as part of a more general phenomenon of psychic tone similarly dissociated with regard to hemispheric control, including mood, psychomotor baseline, speech rate, and even immunity. The behavioral significance of this psychic tone is to modulate approach versus avoidance behavior.

  17. Split-brain, the right hemisphere, and art: fact and fiction. (United States)

    Zaidel, Dahlia W


    The research studies of complete commissurotomy patients (split-brain) in Roger W. Sperry's psychobiology laboratory at Caltech, Pasadena, galvanized the scientific and intellectual world in the 1960s and 1970s. The findings had an important and enduring impact on brain research in countless areas. Interest in hemispheric specialization in particular was sparked by these studies and paved the way for countless discoveries. Right hemisphere specialization for visuospatial functions and facial processing was confirmed with these patients. The further unraveling of right-hemisphere cognition, the "mute" hemisphere, was a major goal in Sperry's laboratory, and much factual knowledge was learned that was not known previously. However, the linking of art and creativity with the right hemisphere was a nonempirically based inference made not by Sperry's lab but rather by others wishing to "assign" functional hemisphericity. The general assumption was that "art" is anchored in spatial cognition, that it is a nonverbal activity requiring imagery and thus must be controlled by the right, nonlanguage hemisphere. To this day, robust evidence that the right specializes in art expression or art perception is yet to be shown, if for no other reason than that art is not a single, unitary form of expression or cognition. The conjectured right hemisphere-art link turned into a popular story that filtered back into science, shaped future research of brain and art, and overlooked other avenues for insights. This chapter traces and explores this background.

  18. Bilinguals Have Different Hemispheric Lateralization in Visual Word Processing from Monolinguals

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    Sze-Man Lam


    Full Text Available Previous bilingual studies showed reduced hemispheric asymmetry in visual tasks such as face perception in bilinguals compared with monolinguals, suggesting experience in reading one or two languages could be a modulating factor. Here we examined whether difference in hemispheric asymmetry in visual tasks can also be observed in bilinguals who have different language backgrounds. We compared the behavior of three language groups in a tachistoscopic English word sequential matching task: English monolinguals (or alphabetic monolinguals, A-Ms, bilinguals with an alphabetic-L1 and English-L2 (alphabetic-alphabetic bilinguals, AA-Bs, and bilinguals with Chinese-L1 and English-L2 (logographic-alphabetic bilinguals, LA-Bs. The results showed that AA-Bs had a stronger right visual field/ left hemispheric (LH advantage than A-Ms and LA-Bs, suggesting that different language learning experiences can influence how visual words are processed in the brain. In addition, we showed that this effect could be accounted for by a computational model that implements a theory of hemispheric asymmetry in perception (i.e., the Double Filtering by Frequency theory; Ivry & Robertson, 1998; the modeling data suggested that this difference may be due to both the difference in participants' vocabulary size and the difference in word-to-sound mapping between alphabetic and logographic languages.

  19. Inferencing Processes after Right Hemisphere Brain Damage: Maintenance of Inferences (United States)

    Blake, Margaret Lehman


    Purpose: This study was designed to replicate and extend a previous study of inferencing in which some adults with right hemisphere damage (RHD) generated but did not maintain predictive inferences over time (M. Lehman-Blake & C. Tompkins, 2001). Two hypotheses were tested: (a) inferences were deactivated, and (b) selection of previously generated…

  20. Three-dimensional network of Drosophila brain hemisphere


    Mizutani, Ryuta; Saiga, Rino; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio


    The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-d...

  1. Three-dimensional network of Drosophila brain hemisphere

    CERN Document Server

    Mizutani, Ryuta; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio


    The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built by tracing the three-dimensional distribution of X-ray absorption coefficients. The obtained models of neuronal processes were classified into groups on the basis of their three-dimensional structures. These classified groups correspond to neuronal tracts that send long-range projections or repeated structures of the optic lobe. The skeletonized model is also composed of neuronal processes that could not be classified into the groups. The distribution of these unclassified structures correlates with the distribution of contacts between neuronal processes. This suggests that neurons that cannot be classified into typical structures should play important roles in brain functions. The quantitative de...

  2. Modulation of the inter-hemispheric asymmetry of motor-related brain activity using brain-computer interfaces. (United States)

    Pereira, Michael; Sobolewski, Aleksander; Millan, Jose Del R


    Non-invasive brain stimulation has shown promising results in neurorehabilitation for motor-impaired stroke patients, by rebalancing the relative involvement of each hemisphere in movement generation. Similarly, brain-computer interfaces have been used to successfully facilitate movement-related brain activity spared by the infarct. We propose to merge both approaches by using BCI to train stroke patients to rebalance their motor-related brain activity during motor tasks, through the use of online feedback. In this pilot study, we report results showing that some healthy subjects were able to learn to spontaneously up- and/or down-regulate their ipsilateral brain activity during a single session.

  3. Representation Activity of The Right and Left Hemispheres of the Brain

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    N. N. Nikolaenko


    Full Text Available Drawings by psychiatric patients were studied in various states (i in depression; (ii after neuroleptic injection; and (iii during left hemisphere suppression induced by unilateral electroconvulsive seizure (UES. In these states, right hemisphere activation predominates. The results of the study demonstrate that, under the predominance of right hemisphere activation over the left hemisphere, there is a tendency to reproduce the image of the object and to represent it in near space. Drawings by psychiatric patients were also investigated in (i the manic state; (ii after injection of psychotropic drugs which improved the mood; and (iii during right hemisphere suppression following right-sided UES. Under these conditions, left hemisphere activation predominates and the drawings loose the illusion of three-dimensional space. A tendency to reproduce the knowledge and the ideas of the object and to represent it in distant space was observed. Thus, both hemispheres may represent space and elaborate perceptive and conceptional models of the world in different ways. It is probable that different types of representation are based on global (right-hemispheric in comparison with focal (left-hemispheric attention to space.

  4. Developmental Changes in Topological Asymmetry Between Hemispheric Brain White Matter Networks from Adolescence to Young Adulthood. (United States)

    Zhong, Suyu; He, Yong; Shu, Hua; Gong, Gaolang


    Human brain asymmetries have been well described. Intriguingly, a number of asymmetries in brain phenotypes have been shown to change throughout the lifespan. Recent studies have revealed topological asymmetries between hemispheric white matter networks in the human brain. However, it remains unknown whether and how these topological asymmetries evolve from adolescence to young adulthood, a critical period that constitutes the second peak of human brain and cognitive development. To address this question, the present study included a large cohort of healthy adolescents and young adults. Diffusion and structural magnetic resonance imaging were acquired to construct hemispheric white matter networks, and graph-theory was applied to quantify topological parameters of the hemispheric networks. In both adolescents and young adults, rightward asymmetry in both global and local network efficiencies was consistently observed between the 2 hemispheres, but the degree of the asymmetry was significantly decreased in young adults. At the nodal level, the young adults exhibited less rightward asymmetry of nodal efficiency mainly around the parasylvian area, posterior tempo-parietal cortex, and fusiform gyrus. These developmental patterns of network asymmetry provide novel insight into the human brain structural development from adolescence to young adulthood and also likely relate to the maturation of language and social cognition that takes place during this period.

  5. Unbiasing the Brain: The Effects of Meditation upon The Cerebral Hemispheres. (United States)

    Meissner, John; Pirot, Michael


    Assessed the effects of Transcendental Meditation on the perceptual efficiency of the cerebral hemispheres in 20 right-handed men who underwent reaction time trials to an auditory stimulus. Results suggested Transcedental Meditation is an attentional strategy that disrupts the usual biases of the brain. (JAC)

  6. Estimation of blood volume difference between bilateral cerebral hemispheres by means of subtraction method

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    Ueno, Ichiro (Tokyo Women' s Medical Coll. (Japan))


    It would be admitted that by measuring radioactivity of the head after intravenous injection of RI some information could be afforded concerning the cerebral vascular bed. After intravenous injection of sup(99m)Tc-pertechnetate (15mCi), an anterior view scintiscanning was made using a gamma camera combined with a computer system. Two ROIs of about 30 cm/sup 2/ were set bilateral symmetrically and a count rate curve of each ROI was obtained. The brain transit time (BTT) was calculated from first derivative of the initial count rate curve. As an index devoting difference between vascular bed of each hemisphere, the vascular bed difference index (VBDI) was introduced BTT and VBDI were calculated in 104 subjects including 11 normal controls. In most of brain tumor, cerebral hemorrhage, severe head injury and cerebral aneurysm BTTs were prolonged in affected hemispheres. However, in a half of cerebral infarction cases BTTs were rather shortened on the affected side. In normal controls, the absolute value of VBDI was (0.16 +- 0.06(S.D.)). In cases of brain tumor, cerebral hemorrhage and severe head injury, VBDI showed a significant deviation from the normal range, taking plus value. This results suggest, according to the definition of VBDI, vascular beds of the affected hemisphere are abnormally decreased compared with those of non-affected side. In cases of arteriovenous malformation VBDIs were increased on the affected side, reflecting enlarged tangle of arteriols and venous vessels. On the other hand, in cases of cerebral infarction, VBDI varied from case to case, making it difficult to get some conclusion from the present data. VBDI, however, invariably decreased in cases in which the occlusion of arteries were definitely confirmed by angiography.

  7. The Representation of Discourse in the Two Hemispheres: An Individual Differences Investigation (United States)

    Prat, Chantel S.; Long, Debra L.; Baynes, Kathleen


    Two experiments were conducted to investigate discourse representation in the two cerebral hemispheres as a function of reading skill. We used a lateralized visual-field procedure to compare left hemisphere (LH) and right hemisphere (RH) sensitivity to different discourse relations in readers with varying skill levels. In Experiment 1, we…

  8. Analysis of EEG activity during sleep - brain hemisphere symmetry of two classes of sleep spindles (United States)

    Smolen, Magdalena M.


    This paper presents automatic analysis of some selected human electroencephalographic patterns during deep sleep using the Matching Pursuit (MP) algorithm. The periodicity of deep sleep EEG patterns was observed by calculating autocorrelation functions of their percentage contributions. The study confirmed the increasing trend of amplitude-weighted average frequency of sleep spindles from frontal to posterior derivations. The dominant frequencies from the left and the right brain hemisphere were strongly correlated.

  9. Hemispheric Differences in the Recruitment of Semantic Processing Mechanisms (United States)

    Kandhadai, Padmapriya; Federmeier, Kara D.


    This study examined how the two cerebral hemispheres recruit semantic processing mechanisms by combining event-related potential measures and visual half-field methods in a word priming paradigm in which semantic strength and predictability were manipulated using lexically associated word pairs. Activation patterns on the late positive complex…

  10. Speech motor program maintenance, but not switching, is enhanced by left-hemispheric deep brain stimulation in Parkinson's disease. (United States)

    Jones, Harrison N; Kendall, Diane L; Okun, Michael S; Wu, Samuel S; Velozo, Craig; Fernandez, Hubert H; Spencer, Kristie A; Rosenbek, John C


    Speech reaction time (SRT) was measured in a response priming protocol in 12 participants with Parkinson's disease (PD) and hypokinetic dysarthria "on" and "off" left-hemispheric deep brain stimulation (DBS). Speech preparation was measured during speech motor programming in two randomly ordered speech conditions: speech maintenance and switching. Double blind testing was completed in participants with DBS of globus pallidus pars interna (GPi) (n = 5) or subthalamic nucleus (STN) (n = 7). SRT was significantly faster in the maintenance vs switch task, regardless of DBS state. SRT was faster in the speech maintenance task "on" stimulation, while there was no difference in speech switching "on" and "off" DBS. These data suggest that left-hemispheric DBS may have differential effects on aspects of speech preparation in PD. It is hypothesized that speech maintenance improvements may result from DBS-induced cortical enhancements, while the lack of difference in switching may be related to inhibition deficits mediated by the right-hemisphere. Alternatively, DBS may have little influence on the higher level motor processes (i.e., motor planning) which it is believed the switch task engaged to a greater extent than the maintenance task.

  11. Hemispheric differences of motor execution: a near-infrared spectroscopy study. (United States)

    Helmich, Ingo; Rein, Robert; Niermann, Nico; Lausberg, Hedda


    Distal movements of the limbs are predominantly controlled by the contralateral hemisphere. However, functional neuroimaging studies do not unequivocally demonstrate a lateralization of the cerebral activation during hand movements. While some studies show a predominant activation of the contralateral hemisphere, other studies provide evidence for a symmetrically distributed bihemispheric activation. However, the divergent results may also be due to methodological shortcomings. Therefore, the present study using functional near-infrared spectroscopy examines cerebral activation in both hemispheres during motor actions of the right and left hands. Twenty participants performed a flexion/extension task with the right- or left-hand thumb. Cerebral oxygenation changes were recorded from 48 channels over the primary motor, pre-motor, supplementary motor, primary somatosensory cortex, subcentral area, and the supramarginal gyrus of each hemisphere. A consistent increase of cerebral oxygenation was found for oxygenated and for total hemoglobin in the hemisphere contralateral to the moving hand, regardless of the laterality. These findings are in line with previous data from localization [1-3] and brain imaging studies [4-6]. The present data support the proposition that there is no hemispheric specialization for simple distal motor tasks. Both hemispheres are equally activated during movement of the contralateral upper limb.

  12. Right hemisphere dominance directly predicts both baseline V1 cortical excitability and the degree of top-down modulation exerted over low-level brain structures. (United States)

    Arshad, Q; Siddiqui, S; Ramachandran, S; Goga, U; Bonsu, A; Patel, M; Roberts, R E; Nigmatullina, Y; Malhotra, P; Bronstein, A M


    Right hemisphere dominance for visuo-spatial attention is characteristically observed in most right-handed individuals. This dominance has been attributed to both an anatomically larger right fronto-parietal network and the existence of asymmetric parietal interhemispheric connections. Previously it has been demonstrated that interhemispheric conflict, which induces left hemisphere inhibition, results in the modulation of both (i) the excitability of the early visual cortex (V1) and (ii) the brainstem-mediated vestibular-ocular reflex (VOR) via top-down control mechanisms. However to date, it remains unknown whether the degree of an individual's right hemisphere dominance for visuospatial function can influence, (i) the baseline excitability of the visual cortex and (ii) the extent to which the right hemisphere can exert top-down modulation. We directly tested this by correlating line bisection error (or pseudoneglect), taken as a measure of right hemisphere dominance, with both (i) visual cortical excitability measured using phosphene perception elicited via single-pulse occipital trans-cranial magnetic stimulation (TMS) and (ii) the degree of trans-cranial direct current stimulation (tDCS)-mediated VOR suppression, following left hemisphere inhibition. We found that those individuals with greater right hemisphere dominance had a less excitable early visual cortex at baseline and demonstrated a greater degree of vestibular nystagmus suppression following left hemisphere cathodal tDCS. To conclude, our results provide the first demonstration that individual differences in right hemisphere dominance can directly predict both the baseline excitability of low-level brain structures and the degree of top-down modulation exerted over them.

  13. A hemisphere array for non-invasive ultrasound brain therapy and surgery (United States)

    Clement, G. T.; Sun, Jie; Giesecke, Tonia; Hynynen, Kullervo


    Ultrasound phased arrays may offer a method for non-invasive deep brain surgery through the skull. In this study a hemispherical phased array system is developed to test the feasibility of trans-skull surgery. The hemispherical shape is incorporated to maximize the penetration area on the skull surface, thus minimizing unwanted heating. Simulations of a 15 cm radius hemisphere divided into 11, 64, 228 and 512 elements are presented. It is determined that 64 elements are sufficient for correcting scattering and reflection caused by trans-skull propagation. An optimal operating frequency near 0.7 MHz is chosen for the array from numerical and experimental thermal gain measurements comparing the power between the transducer focus and the skull surface. A 0.665 MHz air-backed PZT array is constructed and evaluated. The array is used to focus ultrasound through an ex vivo human skull and the resulting fields are measured before and after phase correction of the transducer elements. Finally, to demonstrate the feasibility of trans-skull therapy, thermally induced lesions are produced through a human skull in fresh tissue placed at the ultrasound focus inside the skull.

  14. Brain processing of consonance/dissonance in musicians and controls: a hemispheric asymmetry revisited. (United States)

    Proverbio, Alice Mado; Orlandi, Andrea; Pisanu, Francesca


    It was investigated to what extent musical expertise influences the auditory processing of harmonicity by recording event-related potentials. Thirty-four participants (18 musicians and 16 controls) were asked to listen to hundreds of chords, differing in their degree of consonance, their complexity (from two to six composing sounds) and their range (distance of two adjacent pitches, from quartertones to more than 18 semitone steps). The task consisted of detecting rare targets. An early auditory N1 was observed that was modulated by chord dissonance in both groups. The response was generated in the right medial temporal gyrus (MTG) for consonant chords but in the left MTG for dissonant chords according to swLORETA reconstruction performed. An anterior negativity (N2) was enhanced only in musicians in response to chords featuring quartertones, thus suggesting a greater pitch sensitivity for simultaneous pure tones in the skilled brain. The P300 was affected by the frequency range only in musicians, who also showed a greater sensitivity to sound complexity. A strong left hemispheric specialization for processing quartertones in the left temporal cortex of musicians was observed at N2 level (250-350 ms), which was observed on the right side in controls. Additionally, in controls, widespread activity of the right limbic area was associated with listening to close frequencies causing disturbing beats, possibly suggesting a negative aesthetic appreciation for these stimuli. Overall, the data show a finer and more tuned neural representation of pitch intervals in musicians, linked to a marked specialization of their left temporal cortex (BA21/38).

  15. Focal attenuation of specific electroencephalographic power over the right parahippocampal region during transcerebral copper screening in living subjects and hemispheric asymmetric voltages in fixed brain tissue. (United States)

    Rouleau, Nicolas; Lehman, Brendan; Persinger, Michael A


    Covering the heads of human volunteers with a toque lined with copper mesh compared to no mesh resulted in significant diminishments in quantitative electroencephalographic power within theta and beta-gamma bands over the right caudal hemisphere. The effect was most evident in women compared to men. The significant attenuation of power was verified by LORETA (low resolution electromagnetic tomography) within the parahippocampal region of the right hemisphere. Direct measurements of frequency-dependent voltages of coronal section preserved in ethanol-formalin-acetic acid from our human brain collection revealed consistently elevated power (0.2μV(2)Hz(-1)) in right hemispheric structures compared to left. The discrepancy was most pronounced in the grey (cortical) matter of the right parahippocampal region. Probing the superficial convexities of the cerebrum in an unsectioned human brain demonstrated rostrocaudal differences in hemispheric spectral power density asymmetries, particularly over caudal and parahippocampal regions, which were altered as a function of the chemical and spatial contexts imposed upon the tissue. These results indicate that the heterogeneous response of the human cerebrum to covering of the head by a thin conductor could reflect an intrinsic structure and unique electrical property of the (entorhinal) cortices of the right caudal hemisphere that persists in fixed tissue.

  16. Hemispherical total emissivity of Hastelloy N with different surface conditions (United States)

    Gordon, Andrew J.; Walton, Kyle L.; Ghosh, Tushar K.; Loyalka, Sudarshan K.; Viswanath, Dabir S.; Tompson, Robert V.


    The hemispherical total emissivity of Hastelloy N (a candidate structural material for Next Generation Nuclear Plants (NGNPs), particularly for the molten fluoride cooled reactors) was measured using an experimental set-up that was constructed in accordance with the standard ASTM C835-06. The material surface conditions included: (i) 'as received' (original) sample from the supplier; (ii) samples with increased surface roughness through sand blasting; (iii) oxidized surface, and (iv) samples coated with graphite powder. The emissivity of the as received samples varied from around 0.22 to 0.28 in the temperature range of 473 K to 1498 K. The emissivity increased when the roughness of the surface increased compared to an as received sample. When Hastelloy N was oxidized in air at 1153 K or coated with graphite powder, its emissivity increased substantially. The sample sand blasted with 60 grit beads and sprinkled with graphite powder showed an increase of emissivity from 0.2 to 0.60 at 473 K and from 0.25 to 0.67 at 1473 K. The oxidized surface showed a similar behavior: an increase in emissivity compared to an unoxidized sample. This increase in emissivity has strong favorable safety implications in terms of decay heat removal in post-accident environments. The data were compared with another Hastelloy family member, Hastelloy X.

  17. Population variation in neuroendocrine activity is associated with behavioral inhibition and hemispheric brain structure in young rhesus monkeys. (United States)

    Short, Sarah J; Lubach, Gabriele R; Shirtcliff, Elizabeth A; Styner, Martin A; Gilmore, John H; Coe, Christopher L


    Population variation in hypothalamic-pituitary-adrenal (HPA) activity and reactivity was assessed in a healthy sample of 48 juvenile rhesus monkeys. Cluster analysis of the HPA profiles revealed four distinct neuroendocrine phenotypes based on six indices of HPA functioning. Behavioral reactivity was also evaluated in response to novel stimuli, and revealed marked differences between animals in the highest- and lowest-cortisol clusters. Specifically, animals in the high-cortisol cluster showed larger stress-induced cortisol responses and blunted feedback sensitivity to dexamethasone. They were also emotionally reactive, displayed more aggressive behaviors, and were less likely to approach novel objects. In contrast, monkeys in the low-cortisol cluster were more likely to approach and explore novel objects. Representative animals with high or low cortisol profiles were scanned with Magnetic Resonance Imaging to evaluate structural differences in global and regional gray matter (GM) and white matter (WM) volumes. Monkeys with higher cortisol reactivity evinced less hemispheric brain asymmetry, due to decreased GM in the right hemisphere. Stress reactivity was inversely related to global GM and positively related to total cerebrospinal fluid volume. This inverse relationship was also observed in several stress-sensitive regions, including prefrontal and frontal cortices. Our study demonstrates that population variation in pituitary-adrenal activity is related to behavioral disposition and cerebral structure in this nonhuman primate species.

  18. Morphometric variability of precuneus in relation to gender and the hemisphere of human brain

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    Spasojević Goran


    Full Text Available Precuneus, a quadrangular gyrus of the medial surface of the human parietal lobe, is bound by three primary brain sulci and by superior hemispheric border. Precise encephalometric data about precuneus are important in the studies of brain lateralization, sex dimorphism, and brain functions in general. In this study, total and visible (exstrasulcal surface area of the precuneus were measured on 50 brains of the adult persons (31 male, and 29 female, together with the investigation of its relationship to the side (left/right and gender (sex dimorphism. The average total surface area of the precuneus was 16.07 cm2 on the right (males 16.44 cm2, females 15.27 cm2, and 15.44 cm2 on the left (males 15.67 cm2, females 14.62 cm2. The average visible (extrasulcal surface area of cortex of precuneus was 9.97 cm2 on the left (males 10.75 cm2, females 8.91 cm2, and 9.38 cm2 on the right (males 10.25 cm2, females 8.19 cm2. Exstrasulcal surface area of the left precuneus was larger, by 0.59 cm on the average, which was not statistically significant. Total surface area of precuneus of males was significantly larger on the right (16.44 cm2 (p<0.01 than on the left (15.67 cm2. In females it was also larger on the right (15.27 cm2 than on the left (14.62 cm2, but with no statistical significance. Visible (exstrasulcal surface area of both, (left and right precuneus of males was highly significantly larger in comparison with the females (p<0.001. The obtained results and other facts suggested that sex dimorphism of human brain, including precuneus, was present, but not always easily observable studied or proven in all the details.

  19. Preschoolers' Mental Rotation: Sex Differences in Hemispheric Asymmetry (United States)

    Hahn, Nicola; Jansen, Petra; Heil, Martin


    Mental rotation performance has been found to produce one of the largest sex differences in cognition accompanied by sex differences in functional cerebral asymmetry. Although sex differences in mental rotation performance can be reliably demonstrated as early as age 5 years old, that is, long before puberty, no data exist as to whether…

  20. Drivers of hemispheric differences in return dates of mid-latitude stratospheric ozone to historical levels

    Directory of Open Access Journals (Sweden)

    H. Garny


    Full Text Available Chemistry-climate models (CCMs project an earlier return of northern mid-latitude total column ozone to 1980 values compared to the southern mid-latitudes. The chemical and dynamical drivers of this hemispheric difference are investigated in this study. The hemispheric asymmetry in return dates is a robust result across different CCMs and is qualitatively independent of the method used to estimate return dates. However, the differences in dates of return to 1980 levels between the southern and northern mid-latitudes can vary between 0 and 30 yr across the range of CCM projections analyzed. An attribution analysis performed with two CCMs shows that chemically-induced changes in ozone are the major driver of the earlier return of ozone to 1980 levels in northern mid-latitudes; transport changes are of minor importance. This conclusion is supported by the fact that the spread in the simulated hemispheric difference in return dates across an ensemble of twelve models is only weakly related to the spread in the simulated hemispheric asymmetry of trends in the strength of the Brewer–Dobson circulation. The causes for chemically-induced asymmetric ozone trends relevant for the total column ozone return date differences are found to be (i stronger increases in ozone production due to enhanced NOx concentrations in the Northern Hemisphere lowermost stratosphere and troposphere, (ii stronger decreases in the destruction rates of ozone by the NOx cycle in the Northern Hemisphere lower stratosphere linked to effects of dynamics and temperature on NOx concentrations and (iii an increasing efficiency of heterogeneous ozone destruction by Cly in the Southern Hemisphere mid-latitudes as a result of decreasing temperatures.

  1. Sex differences in brain structure in auditory and cingulate regions


    Brun, Caroline C.; Lepore, Natasha; Luders, Eileen; Chou, Yi-Yu; Madsen, Sarah K.; Toga, Arthur W; Thompson, Paul M.


    We applied a new method to visualize the three-dimensional profile of sex differences in brain structure based on MRI scans of 100 young adults. We compared 50 men with 50 women, matched for age and other relevant demographics. As predicted, left hemisphere auditory and language-related regions were proportionally expanded in women versus men, suggesting a possible structural basis for the widely replicated sex differences in language processing. In men, primary visual, and visuo-spatial asso...


    Directory of Open Access Journals (Sweden)

    Mohammad Hadi Mahmoodi


    Full Text Available Oral skills are important components of language competence. To have good and acceptable listening and speaking, one must have good pronunciation, which encompasses segmental and suprasegmental features. Despite extensive studies on the role of segmental features and related issues in listening and speaking, there is paucity of research on the role of suprasegmental features in the same domain. Conducting studies which aim at shedding light on the issues related to learning suprasegmental features can help language teachers and learners in the process of teaching/learning English as a foreign language. To this end, this study was designed to investigate the relationship among brain hemispheric dominance, gender, attitudes towards L1 and L2, and learning suprasegmental features in Iranian EFL learners. First, 200 Intermediate EFL learners were selected from different English language teaching institutes in Hamedan and Isfahan, two provinces in Iran, as the sample. Prior to the main stage of the study, Oxford Placement Test (OPT was used to homogenize the proficiency level of all the participants. Then, the participants were asked to complete the Edinburgh Handedness Questionnaire to determine their dominant hemisphere. They were also required to answer two questionnaires regarding their attitudes towards L1 and L2. Finally, the participants took suprasegmental features test. The results of the independent samples t-tests indicated left-brained language learners’ superiority in observing and learning suprasegmental features. It was also found that females are better than males in producing suprasegmental features. Furthermore, the results of Pearson Product Moment Correlations indicated that there is significant relationship between attitude towards L2 and learning suprasegmental features. However, no significant relationship was found between attitude towards L1 and learning English suprasegmental features. The findings of this study can

  3. Morphological and histochemical changes in the brain stem in case of experimental hemispheric intracerebral hemorrhage

    Directory of Open Access Journals (Sweden)

    S. I. Tertishniy


    Full Text Available Aim. Investigation of the extent of morphological changes and activity of biogenic amines (according to the intensity of luminescence in the neurons of the brain stem in intracerebral hemorrhage (ICH. Methods and results. ICH was designed on 29 white rats of Vistar line by the administration of autologous blood in the cerebral hemisphere. It was revealed that increased luminescence intensity by 18.4±5.5% was registered in monoaminergic neurons in 1–6 hours after experimental ICH. After 12 hours – 1 day development of dislocation syndrome leads to mosaic focal ischemic neuronal injuries with maximum reduction in the level of catecholamines by 29.5±5.0% compared with control cases. Three–6 days after ICH on a background of selective neuronal necrosis in substantial number of neurons in the nuclei of the brainstem the level of catecholamines is significantly reduced. Conclusion. Disclosed observations reflect significant functional pathology of neurons responsible for the regulation of cardiorespiratory function and may underlie disturbances of integrative activity in the brain stem in general.

  4. Sex differences in brain epigenetics. (United States)

    Menger, Yannick; Bettscheider, Marc; Murgatroyd, Chris; Spengler, Dietmar


    Sexual differentiation of the brain takes place during a perinatal-sensitive time window as a result of gonadal hormone-induced activational and organizational effects on neuronal substrates. Increasing evidence suggests that epigenetic mechanisms can contribute to the establishment and maintenance of some aspects of these processes, and that these epigenetic mechanisms may themselves be under the control of sex hormones. Epigenetic programming of neuroendocrine and behavioral phenotypes frequently occurs sex specifically, pointing to sex differences in brain epigenetics as a possible determinant. Understanding how sex-specific epigenomes and sex-biased responses to environmental cues contribute to the development of brain diseases might provide new insights for epigenetic therapy.

  5. Cerebral and callosal organisation in a right hemisphere dominant "split brain" patient.


    Lutsep, H.L.; Wessinger, C M; Gazzaniga, M S


    Patients described in previous reports who have undergone corpus callostomy for control of seizures have been left hemisphere dominant for language. To determine the hemispheric localisation (and possible coexistence) of language and traditional right hemisphere skills in reversed dominance, the first right hemisphere dominant corpus callostomy patient was studied. Localisation of callosal functions was also investigated, as MRI showed 1.5 cm of spared callosal body. The patient, KO, a 15 yea...

  6. Rigidity, Chaos and Integration: Hemispheric Interaction and Individual Differences in Metaphor Comprehension

    Directory of Open Access Journals (Sweden)

    Miriam eFaust


    Full Text Available Neurotypical individuals cope flexibly with the full range of semantic relations expressed in human language, including metaphoric relations. This impressive semantic ability may be associated with distinct and flexible patterns of hemispheric interaction, including higher right hemisphere (RH involvement for processing novel metaphors. However, this ability may be impaired in specific clinical conditions, such as Asperger syndrome and schizophrenia. The impaired semantic processing is accompanied by different patterns of hemispheric interaction during semantic processing, showing either reduced (in Asperger or excessive (in schizophrenia RH involvement. This paper interprets these individual differences using the terms Rigidity, Chaos and Integration, which describe patterns of semantic memory network states that either lead to semantic well-being or are disruptive of it. We argue that these semantic network states lie on a rigidity-chaos semantic continuum. We define these terms via network science terminology and provide network, cognitive and neural evidence to support our claim. This continuum includes LH hyper-rigid semantic memory state on one end (e.g., in persons with Asperger syndrome, and RH chaotic and over-flexible semantic memory state on the other end (e.g., in persons with schizophrenia. In between these two extremes lie different states of semantic memory structure which are related to individual differences in semantic creativity. We suggest that efficient semantic processing is achieved by semantic integration, a balance between semantic rigidity and semantic chaos. Such integration is achieved via intra-hemispheric communication. However, impairments to this well-balanced and integrated pattern of hemispheric interaction, e.g., when one hemisphere dominates the other, may lead to either semantic rigidity or semantic chaos, moving away from semantic integration and thus impairing the processing of metaphoric language.

  7. Sexual differences of human brain

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    Masoud Pezeshki Rad


    Full Text Available During the last decades there has been an increasing interest in studying the differences between males and females. These differences extend from behavioral to cognitive to micro- and macro- neuro-anatomical aspects of human biology. There have been many methods to evaluate these differences and explain their determinants. The most studied cause of this dimorphism is the prenatal sex hormones and their organizational effect on brain and behavior. However, there have been new and recent attentions to hormone's activational influences in puberty and also the effects of genomic imprinting. In this paper, we reviewed the sex differences of brain, the evidences for possible determinants of these differences and also the methods that have been used to discover them. We reviewed the most conspicuous findings with specific attention to macro-anatomical differences based on Magnetic Resonance Imaging (MRI data. We finally reviewed the findings and the many opportunities for future studies.

  8. Hemispheric asymmetry of visual scene processing in the human brain: evidence from repetition priming and intrinsic activity. (United States)

    Stevens, W Dale; Kahn, Itamar; Wig, Gagan S; Schacter, Daniel L


    Asymmetrical specialization of cognitive processes across the cerebral hemispheres is a hallmark of healthy brain development and an important evolutionary trait underlying higher cognition in humans. While previous research, including studies of priming, divided visual field presentation, and split-brain patients, demonstrates a general pattern of right/left asymmetry of form-specific versus form-abstract visual processing, little is known about brain organization underlying this dissociation. Here, using repetition priming of complex visual scenes and high-resolution functional magnetic resonance imaging (MRI), we demonstrate asymmetrical form specificity of visual processing between the right and left hemispheres within a region known to be critical for processing of visual spatial scenes (parahippocampal place area [PPA]). Next, we use resting-state functional connectivity MRI analyses to demonstrate that this functional asymmetry is associated with differential intrinsic activity correlations of the right versus left PPA with regions critically involved in perceptual versus conceptual processing, respectively. Our results demonstrate that the PPA comprises lateralized subregions across the cerebral hemispheres that are engaged in functionally dissociable yet complementary components of visual scene analysis. Furthermore, this functional asymmetry is associated with differential intrinsic functional connectivity of the PPA with distinct brain areas known to mediate dissociable cognitive processes.

  9. Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

    Directory of Open Access Journals (Sweden)

    Camillia Bouchon

    Full Text Available The repeated presentation of stimuli typically attenuates neural responses (repetition suppression or, less commonly, increases them (repetition enhancement when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown.This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008. In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar.Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140, and simpler presentation conditions (blocked rather than interleaved would influence repetition effects at birth.Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern.Taken together with Gervain et al. (2008, this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement

  10. Left Hemisphere Regions Are Critical for Language in the Face of Early Left Focal Brain Injury (United States)

    Beharelle, Anjali Raja; Dick, Anthony Steven; Josse, Goulven; Solodkin, Ana; Huttenlocher, Peter R.; Levine, Susan C.; Small, Steven L.


    A predominant theory regarding early stroke and its effect on language development, is that early left hemisphere lesions trigger compensatory processes that allow the right hemisphere to assume dominant language functions, and this is thought to underlie the near normal language development observed after early stroke. To test this theory, we…

  11. Hemispheric differences in corticospinal excitability and in transcallosal inhibition in relation to degree of handedness.

    Directory of Open Access Journals (Sweden)

    Travis Davidson

    Full Text Available In this study, we examined hemispheric differences in corticospinal excitability and in transcallosal inhibition in a selected group of young adults (n = 34 grouped into three handedness categories (RH: strongly right-handed, n = 17; LH: strongly left-handed, n = 10; MH: mixed-handed, n = 7 based on laterality quotients (LQ derived from the Edinburgh Handedness Inventory. Performance measures were also used to derive a laterality index reflecting right-left asymmetries in manual dexterity (Dextli and in finger tapping speed (Speedli. Corticospinal excitability was assessed in each hemisphere by means of transcranial magnetic stimulation (TMS using the first dorsal interosseus as the target muscle. TMS measures consisted of resting motor threshold (rMT, motor evoked potential (MEP recruitment curve (RC and the contralateral silent period (cSP with the accompanying MEP facilitation. Hemispheric interactions were assessed by means of the ipsilateral silent period (iSP to determine the onset latency and the duration of transcallosal inhibition (i.e., LTI and DTI. Analysis of hemispheric variations in measures of corticospinal excitability revealed no major asymmetries in relation to degrees of laterality or handedness, with the exception of a rightward increase in rMTs in the LH group. Similarly, no clear asymmetries were found when looking at hemispheric variations in measures of transcallosal inhibition. However, a large group effect was detected for LTI measures, which were found to be significantly shorter in the MH group than in either the LH or RH group. MH participants also tended to show longer DTI than the other participants. Further inspection of overall variations in LTI and DTI measures as a function of LQs revealed that both variables followed a non-linear relationship, which was best described by a 2(nd order polynomial function. Overall, these findings provide converging evidence for a link between mixed-handedness and more efficient

  12. Critical brain regions for action recognition: lesion symptom mapping in left hemisphere stroke. (United States)

    Kalénine, Solène; Buxbaum, Laurel J; Coslett, Harry Branch


    A number of conflicting claims have been advanced regarding the role of the left inferior frontal gyrus, inferior parietal lobe and posterior middle temporal gyrus in action recognition, driven in part by an ongoing debate about the capacities of putative mirror systems that match observed and planned actions. We report data from 43 left hemisphere stroke patients in two action recognition tasks in which they heard and saw an action word ('hammering') and selected from two videoclips the one corresponding to the word. In the spatial recognition task, foils contained errors of body posture or movement amplitude/timing. In the semantic recognition task, foils were semantically related (sawing). Participants also performed a comprehension control task requiring matching of the same verbs to objects (hammer). Using regression analyses controlling for both the comprehension control task and lesion volume, we demonstrated that performance in the semantic gesture recognition task was predicted by per cent damage to the posterior temporal lobe, whereas the spatial gesture recognition task was predicted by per cent damage to the inferior parietal lobule. A whole-brain voxel-based lesion symptom-mapping analysis suggested that the semantic and spatial gesture recognition tasks were associated with lesioned voxels in the posterior middle temporal gyrus and inferior parietal lobule, respectively. The posterior middle temporal gyrus appears to serve as a central node in the association of actions and meanings. The inferior parietal lobule, held to be a homologue of the monkey parietal mirror neuron system, is critical for encoding object-related postures and movements, a relatively circumscribed aspect of gesture recognition. The inferior frontal gyrus, on the other hand, was not predictive of performance in any task, suggesting that previous claims regarding its role in action recognition may require refinement.

  13. "The archeologist's career ended in ruins": hemispheric differences in pun comprehension in autism. (United States)

    Kana, Rajesh K; Wadsworth, Heather M


    Appropriate interpretation of figurative language involves inferring the speaker's intent by integrating word meaning with context. In disorders like autism, understanding intended and contextual meanings in language may pose a challenge. Such difficulties are prevalent even when individuals exhibit otherwise fluent language ability (Szatmari et al., 1990). A pun is a rhetorical technique in which a speaker deliberately invokes multiple meanings through a word or phrase likely resulting in a joke. Comprehending puns may involve identifying multiple meanings of a word, embedding it in right contexts, and understanding the underlying humor. This fMRI study investigated the brain responses associated with figures of speech like puns. In the fMRI scanner, participants read sentences containing puns (e.g. To write with a broken pencil is pointless) and control sentences (literal meaning) presented in a blocked design format. The participants' task was to silently read and understand one meaning (in the literal condition) or two meanings (in the pun condition). Participants with autism, relative to typical controls, showed an increase in overall activation while comprehending sentences containing puns, particularly within the right hemisphere as well as in relatively posterior brain areas. Overall, there was reduced response in left hemisphere areas, reduced response to humor, and more distributed recruitment of regions in autism relative to control participants. We also examined the relationship between symptom severity in autism and verbal ability with brain responses to pun comprehension finding negative and positive correlations respectively. Overall, the results from the present study suggest that individuals with autism resort to altered neural routes in comprehending language in general, and figurative language in particular.

  14. Selective intra-arterial administration of {sup 18}F-FDG to the rat brain - effects on hemispheric uptake

    Energy Technology Data Exchange (ETDEWEB)

    Arnberg, Fabian; Samen, Erik; Lundberg, Johan; Grafstroem, Jonas; Soederman, Michael; Stone-Elander, Sharon; Holmin, Staffan [Karolinska Institutet, Department of Clinical Neuroscience, Stockholm (Sweden); Karolinska University Hospital-Solna, Department of Neuroradiology, Stockholm (Sweden); Lu, Li [Karolinska University Hospital-Solna, KERIC, Stockholm (Sweden)


    The purpose of this study was to investigate the radioligand uptake and iodine contrast distribution in the intra- and extracranial circulation of the rat, after intra-arterial injections to the common carotid artery and different parts of the internal carotid artery. All animal experiments were carried out in accordance with Karolinska Institutet's guidelines and were approved by the local laboratory animal ethics committee. We used clinical neurointerventional systems to place microcatheters in the extra- or intracranial carotid artery of 15 Sprague-Dawley rats. Here, injection dynamics of iodine contrast was assessed using digital subtraction angiography. Maintaining the catheter position, the animals were placed in a micro PET and small-animal positron emission tomography (PET) was used to analyze injections [2-{sup 18}F]-2-fluoro-2-deoxy-d-glucose ({sup 18}F-FDG). Microcatheters had to be placed in the intracranial carotid artery (iICA) for the infusate to distribute to the brain. Selective injection via the iICA resulted in a 9-fold higher uptake of {sup 18}F-FDG in the injected hemisphere (p < 0.005) compared to both intravenous and more proximal carotid artery injections. Furthermore, selective injection gave a dramatically improved contrast between the brain and extracranial tissue. Intra-arterial injection increases the cerebral uptake of a radiotracer dramatically compared to systemic injection. This technique has potential applications for endovascular treatment of malignancies allowing intra-interventional modifications of injection strategy, based on information on tumor perfusion and risk to surrounding normal parenchyma. Furthermore the technique may increase diagnostic sensitivity and avoid problems due to peripheral pharmacological barriers and first passage metabolism of labile tracers. (orig.)

  15. Using ipsilateral motor signals in the unaffected cerebral hemisphere as a signal platform for brain-computer interfaces in hemiplegic stroke survivors (United States)

    Bundy, David T.; Wronkiewicz, Mark; Sharma, Mohit; Moran, Daniel W.; Corbetta, Maurizio; Leuthardt, Eric C.


    Brain-computer interface (BCI) systems have emerged as a method to restore function and enhance communication in motor impaired patients. To date, this has been applied primarily to patients who have a compromised motor outflow due to spinal cord dysfunction, but an intact and functioning cerebral cortex. The cortical physiology associated with movement of the contralateral limb has typically been the signal substrate that has been used as a control signal. While this is an ideal control platform in patients with an intact motor cortex, these signals are lost after a hemispheric stroke. Thus, a different control signal is needed that could provide control capability for a patient with a hemiparetic limb. Previous studies have shown that there is a distinct cortical physiology associated with ipsilateral, or same-sided, limb movements. Thus far, it was unknown whether stroke survivors could intentionally and effectively modulate this ipsilateral motor activity from their unaffected hemisphere. Therefore, this study seeks to evaluate whether stroke survivors could effectively utilize ipsilateral motor activity from their unaffected hemisphere to achieve this BCI control. To investigate this possibility, electroencephalographic (EEG) signals were recorded from four chronic hemispheric stroke patients as they performed (or attempted to perform) real and imagined hand tasks using either their affected or unaffected hand. Following performance of the screening task, the ability of patients to utilize a BCI system was investigated during on-line control of a one-dimensional control task. Significant ipsilateral motor signals (associated with movement intentions of the affected hand) in the unaffected hemisphere, which were found to be distinct from rest and contralateral signals, were identified and subsequently used for a simple online BCI control task. We demonstrate here for the first time that EEG signals from the unaffected hemisphere, associated with overt and

  16. Using Ipsilateral Motor Signals in the Unaffected Cerebral Hemisphere as a Signal Platform for Brain Computer Interfaces in Hemiplegic Stroke Survivors (United States)

    Bundy, David T.; Wronkiewicz, Mark; Sharma, Mohit; Moran, Daniel W.; Corbetta, Maurizio; Leuthardt, Eric C.


    Objective Brain computer interface (BCI) systems have emerged as a method to restore function and enhance communication in motor impaired patients. To date, this has been primarily applied to patients who have a compromised motor outflow due to spinal cord dysfunction, but an intact and functioning cerebral cortex. The cortical physiology associated with movement of the contralateral limb has typically been the signal substrate that has been used as a control signal. While this is an ideal control platform in patients with an intact motor cortex, these signals are lost after a hemispheric stroke. Thus, a different control signal is needed that could provide control capability for a patient with a hemiparetic limb. Previous studies have shown that there is a distinct cortical physiology associated with ipsilateral, or same sided, limb movements. Thus far, it was unknown whether stroke survivors could intentionally and effectively modulate this ipsilateral motor activity from their unaffected hemisphere. Therefore, this study seeks to evaluate whether stroke survivors could effectively utilize ipsilateral motor activity from their unaffected hemisphere to achieve this BCI control. Approach To investigate this possibility, electroencephalographic (EEG) signals were recorded from four chronic hemispheric stroke patients as they performed (or attempted to perform) real and imagined hand tasks using either their affected or unaffected hand. Following performance of the screening task, the ability of patients to utilize a BCI system was investigated during on-line control of a 1-dimensional control task. Main Results Significant ipsilateral motor signals (associated with movement intentions of the affected hand) in the unaffected hemisphere, which were found to be distinct from rest and contralateral signals, were identified and subsequently used for a simple online BCI control task. We demonstrate here for the first time that EEG signals from the unaffected hemisphere

  17. A novel, implicit treatment for language comprehension processes in right hemisphere brain damage: Phase I data. (United States)

    Tompkins, Connie A; Blake, Margaret T; Wambaugh, Julie; Meigh, Kimberly


    BACKGROUND: This manuscript reports the initial phase of testing for a novel, "Contextual constraint" treatment, designed to stimulate inefficient language comprehension processes in adults with right hemisphere brain damage (RHD). Two versions of treatment were developed to target two normal comprehension processes that have broad relevance for discourse comprehension and that are often disrupted by RHD: coarse semantic coding and suppression. The development of the treatment was informed by two well-documented strengths of the RHD population. The first is consistently better performance on assessments that are implicit, or nearly so, than on explicit, metalinguistic measures of language and cognitive processing. The second is improved performance when given linguistic context that moderately-to-strongly biases an intended meaning. Treatment consisted of providing brief context sentences to prestimulate, or constrain, intended interpretations. Participants made no explicit associations or judgments about the constraint sentences; rather, these contexts served only as implicit primes. AIMS: This Phase I treatment study aimed to determine the effects of a novel, implicit, Contextual Constraint treatment in adults with RHD whose coarse coding or suppression processes were inefficient. Treatment was hypothesized to speed coarse coding or suppression function in these individuals. METHODS #ENTITYSTARTX00026; PROCEDURES: Three adults with RHD participated in this study, one (P1) with a coarse coding deficit and two (P2, P3) with suppression deficits. Probe tasks were adapted from prior studies of coarse coding and suppression in RHD. The dependent measure was the percentage of responses that met predetermined response time criteria. When pre-treatment baseline performance was stable, treatment was initiated. There were two levels of contextual constraint, Strong and Moderate, and treatment for each item began with the provision of the Strong constraint context. OUTCOMES

  18. How to engage the right brain hemisphere in aphasics without even singing: evidence for two paths of speech recovery. (United States)

    Stahl, Benjamin; Henseler, Ilona; Turner, Robert; Geyer, Stefan; Kotz, Sonja A


    There is an ongoing debate as to whether singing helps left-hemispheric stroke patients recover from non-fluent aphasia through stimulation of the right hemisphere. According to recent work, it may not be singing itself that aids speech production in non-fluent aphasic patients, but rhythm and lyric type. However, the long-term effects of melody and rhythm on speech recovery are largely unknown. In the current experiment, we tested 15 patients with chronic non-fluent aphasia who underwent either singing therapy, rhythmic therapy, or standard speech therapy. The experiment controlled for phonatory quality, vocal frequency variability, pitch accuracy, syllable duration, phonetic complexity and other influences, such as the acoustic setting and learning effects induced by the testing itself. The results provide the first evidence that singing and rhythmic speech may be similarly effective in the treatment of non-fluent aphasia. This finding may challenge the view that singing causes a transfer of language function from the left to the right hemisphere. Instead, both singing and rhythmic therapy patients made good progress in the production of common, formulaic phrases-known to be supported by right corticostriatal brain areas. This progress occurred at an early stage of both therapies and was stable over time. Conversely, patients receiving standard therapy made less progress in the production of formulaic phrases. They did, however, improve their production of non-formulaic speech, in contrast to singing and rhythmic therapy patients, who did not. In light of these results, it may be worth considering the combined use of standard therapy and the training of formulaic phrases, whether sung or rhythmically spoken. Standard therapy may engage, in particular, left perilesional brain regions, while training of formulaic phrases may open new ways of tapping into right-hemisphere language resources-even without singing.

  19. Suppression and Narrative Time Shifts in Adults with Right-Hemisphere Brain Damage (United States)

    Scharp, Victoria L.; Tompkins, Connie A.


    Purpose: This study examined the functioning of a central comprehension mechanism, suppression, in adults with right-hemisphere damage (RHD) while they processed narratives that cued a shift in time frame. In normal language comprehension, mental activation of concepts from a prior time frame is suppressed. The (re)activation of information…

  20. Sex Differences in the Adolescent Brain (United States)

    Lenroot, Rhoshel K.; Giedd, Jay N.


    Adolescence is a time of increased divergence between males and females in physical characteristics, behavior, and risk for psychopathology. Here we will review data regarding sex differences in brain structure and function during this period of the lifespan. The most consistent sex difference in brain morphometry is the 9-12% larger brain size…

  1. Cortical activity in the left and right hemispheres during language-related brain functions

    DEFF Research Database (Denmark)

    Lassen, N A; Larsen, B


    The blood flow to a given brain region increases as the level of neural activity is augmented. Hence mapping of variations in regional cerebral blood flow affords a means of imaging the activity of various brain regions during various types of brain work. The paper summarizes the patterns...

  2. An EEG Investigation of the Differences in the Hemispheric Specialization of Formal and Concrete Operational Persons. (United States)

    Dilling, Richard A.; And Others

    This study attempts to raise and answer the question as to whether lateral specialization of the brain could explain some of the differences in persons at different stages of intellectual development from birth to adulthood according to Piaget's theory of individual development via sequential, qualitatively different stages.…

  3. Frequency-difference MIT imaging of cerebral haemorrhage with a hemispherical coil array: numerical modelling. (United States)

    Zolgharni, M; Griffiths, H; Ledger, P D


    The feasibility of detecting a cerebral haemorrhage with a hemispherical MIT coil array consisting of 56 exciter/sensor coils of 10 mm radius and operating at 1 and 10 MHz was investigated. A finite difference method combined with an anatomically realistic head model comprising 12 tissue types was used to simulate the strokes. Frequency-difference images were reconstructed from the modelled data with different levels of the added phase noise and two types of a priori boundary errors: a displacement of the head and a size scaling error. The results revealed that a noise level of 3 m degrees (standard deviation) was adequate for obtaining good visualization of a peripheral stroke (volume approximately 49 ml). The simulations further showed that the displacement error had to be within 3-4 mm and the scaling error within 3-4% so as not to cause unacceptably large artefacts on the images.

  4. Gender differences in hemispheric organization during divergent thinking: an EEG investigation in human subjects. (United States)

    Razumnikova, Olga M


    This study examined the gender-related differences in EEG patterns during the experimental condition of divergent thinking. The EEG of 36 males and 27 females was recorded from 16 scalp electrodes in rest and while students were solving a creative problem. The spectral power density along with EEG coherence estimates were analyzed in each of the six frequency bands in the 4-30 Hz range. Gender-related differences in the EEG patterns were found during successful divergent thinking. Creative men were characterized by massive increases of amplitude and interhemispheric coherence in the beta2 whereas creative women showed more local increases of the beta2 power and coherence. On the contrary, the task-induced desynchronization of the alpha1 rhythm in creative women was topographically more expanded as compared with men who demonstrated greater interhemispheric coherence than women did. Our results propose a different hemispheric organization in men and women during creative thinking.

  5. Numerical Analysis on Aerodynamic Behavior of a Hemispherical Structure under Different Wind Loading

    Directory of Open Access Journals (Sweden)

    R. Verma


    Full Text Available Light weight and adaptability in structures have attracted researchers towards the development of inflatable structures. These light weighted inflatable structures are used as emergency shelters, as a decoy and also as a permanent building. Earlier reports shows many cases in which these light weight structure have collapsed due to adverse wind conditions. This damage caused to these structures may be attributed to its poor wind resistance design conditions. Also, due to the uncertainties, there is limited and very few information representing the aerodynamic behaviour of the wind over hemispherical dome structures. An attempt is herewith made to find out the aerodynamic behaviour of the wind passing through a hemispherical shaped structure. CFD software FLUENT has been used to perform the analysis of a dome model in Indian wind conditions. Before study, the CFD code has been validated against experimental data available in literature. It is found that the realizable k-ε turbulent model shows good agreement with experimental data. The value of drag coefficient (Cd has been calculated by using frontal area of the structure and it is found out to be 0.32. The results with different wind conditions obtained by CFD shows that the increase in turbulent intensity in the flow field highly influences the drag force and it increase approximately 14% for a highly turbulent wind condition

  6. Differences in task demands influence the hemispheric lateralization and neural correlates of metaphor. (United States)

    Yang, Fanpei Gloria; Edens, Jennifer; Simpson, Claire; Krawczyk, Daniel C


    This study investigated metaphor comprehension in the broader context of task-difference effects and manipulation of processing difficulty. We predicted that right hemisphere recruitment would show greater specificity to processing difficulty rather than metaphor comprehension. Previous metaphor processing studies have established that the left inferior frontal gyrus strongly correlates with metaphor comprehension but there has been controversy about whether right hemisphere (RH) involvement is specific for metaphor comprehension. Functional MRI data were recorded from healthy subjects who read novel metaphors, conventional metaphors, definition-like sentences, or literal sentences. We investigated metaphor processing in contexts where semantic judgment or imagery modulates linguistic judgment. Our findings support the position that the type of task rather than figurative language processing per se modulates the left inferior gyrus (LIFG). RH involvement was more influenced by processing difficulty and less by the novelty or figurativity of linguistic expressions. Our results suggest that figurative language processing depends upon the effects of task-type and processing difficulty on imaging results.

  7. Knowledge about Sounds – Context-Specific Meaning Differently Activates Cortical Hemispheres, Auditory Cortical Fields and Layers in House Mice

    Directory of Open Access Journals (Sweden)

    Diana B. Geissler


    Full Text Available Activation of the auditory cortex (AC by a given sound pattern is plastic, depending, in largely unknown ways, on the physiological state and the behavioral context of the receiving animal and on the receiver's experience with the sounds. Such plasticity can be inferred when house mouse mothers respond maternally to pup ultrasounds right after parturition and naïve females have to learn to respond. Here we use c-FOS immunocytochemistry to quantify highly activated neurons in the AC fields and layers of seven groups of mothers and naïve females who have different knowledge about and are differently motivated to respond to acoustic models of pup ultrasounds of different behavioral significance. Profiles of FOS-positive cells in the AC primary fields (AI, AAF, the ultrasonic field (UF, the secondary field (AII, and the dorsoposterior field (DP suggest that activation reflects in AI, AAF, and UF the integration of sound properties with animal state-dependent factors, in the higher-order field AII the news value of a given sound in the behavioral context, and in the higher-order field DP the level of maternal motivation and, by left-hemisphere activation advantage, the recognition of the meaning of sounds in the given context. Anesthesia reduced activation in all fields, especially in cortical layers 2/3. Thus, plasticity in the AC is field-specific preparing different output of AC fields in the process of perception, recognition and responding to communication sounds. Further, the activation profiles of the auditory cortical fields suggest the differentiation between brains hormonally primed to know (mothers and brains which acquired knowledge via implicit learning (naïve females. In this way, auditory cortical activation discriminates between instinctive (mothers and learned (naïve females cognition.

  8. Knowledge About Sounds-Context-Specific Meaning Differently Activates Cortical Hemispheres, Auditory Cortical Fields, and Layers in House Mice. (United States)

    Geissler, Diana B; Schmidt, H Sabine; Ehret, Günter


    Activation of the auditory cortex (AC) by a given sound pattern is plastic, depending, in largely unknown ways, on the physiological state and the behavioral context of the receiving animal and on the receiver's experience with the sounds. Such plasticity can be inferred when house mouse mothers respond maternally to pup ultrasounds right after parturition and naïve females have to learn to respond. Here we use c-FOS immunocytochemistry to quantify highly activated neurons in the AC fields and layers of seven groups of mothers and naïve females who have different knowledge about and are differently motivated to respond to acoustic models of pup ultrasounds of different behavioral significance. Profiles of FOS-positive cells in the AC primary fields (AI, AAF), the ultrasonic field (UF), the secondary field (AII), and the dorsoposterior field (DP) suggest that activation reflects in AI, AAF, and UF the integration of sound properties with animal state-dependent factors, in the higher-order field AII the news value of a given sound in the behavioral context, and in the higher-order field DP the level of maternal motivation and, by left-hemisphere activation advantage, the recognition of the meaning of sounds in the given context. Anesthesia reduced activation in all fields, especially in cortical layers 2/3. Thus, plasticity in the AC is field-specific preparing different output of AC fields in the process of perception, recognition and responding to communication sounds. Further, the activation profiles of the auditory cortical fields suggest the differentiation between brains hormonally primed to know (mothers) and brains which acquired knowledge via implicit learning (naïve females). In this way, auditory cortical activation discriminates between instinctive (mothers) and learned (naïve females) cognition.

  9. Qualitatively different organizational structures of lexical knowledge in the left and right hemisphere. (United States)

    Drews, E


    The present study investigates and discusses the organization of lexical knowledge in the intact left and right hemisphere within the framework of hemisphere-specific cognitive modes of processing. Using a divided visual field technique, word pairs of concrete nouns had to be judged. Semantic relation was either intraconceptual (coordinates) or interconceptual (locative). The results suggest that the left hemisphere, lexical structures are predominantly based on intraconceptual relationships corresponding to its analytic sequential processing mechanism, whereas in the right hemisphere, lexical entries are exclusively associated by means of interconceptual relationships in accordance with its "gestalthaft" holistic processor.

  10. Reorganization of the Cerebro-Cerebellar Network of Language Production in Patients with Congenital Left-Hemispheric Brain Lesions (United States)

    Lidzba, K.; Wilke, M.; Staudt, M.; Krageloh-Mann, I.; Grodd, W.


    Patients with congenital lesions of the left cerebral hemisphere may reorganize language functions into the right hemisphere. In these patients, language production is represented homotopically to the left-hemispheric language areas. We studied cerebellar activation in five patients with congenital lesions of the left cerebral hemisphere to assess…

  11. Distinguishing lies from jokes: theory of mind deficits and discourse interpretation in right hemisphere brain-damaged patients. (United States)

    Winner, E; Brownell, H; Happé, F; Blum, A; Pincus, D


    Right-hemisphere brain damaged (RHD) patients and a normal control group were tested for their ability to infer first- and second-order mental states and to understand the communicative intentions underlying ironic jokes and lies. Subjects listened to stories involving a character who had either a true or a false belief about another character's knowledge. Stories ended either with an ironic joke or a lie by this character. In the joke stories, the speaker knew that the listener knew the truth (a true second-order belief) and did not expect the listener to believe what was said; in the lie stories, the speaker did not know that the listener actually knew the truth (a false second-order belief) and thus did expect the listener to believe what was said. RHD patients performed significantly worse than control subjects on one of two measures of second-order belief, which suggests that the ability to make second-order mental state attributions is fragile and unreliable following right-hemisphere damage. RHD patients in addition performed worse than controls when asked to distinguish lies from jokes, confirming their known difficulties with discourse interpretation. For both groups, the ability to distinguish lies from jokes was strongly correlated with two measures of the ability to attribute correctly second-order beliefs. These results suggest that the fragility of RHD patients' understanding of second-order mental states underlies a portion of their difficulties in discourse comprehension, but that the underlying impairment is not restricted to right hemisphere dysfunction.

  12. Complementary functions of the two brain hemispheres: comparisons with earlier conceptions and implications for individual and society. (United States)

    Zeier, H


    The concept of different functions for the left and right cerebral hemispheres coincides in an astonishing way with earlier philosophical and psychological work which divided the human mind into two complementary functions without having a neurophysiological explanation. Representative are the ideas of Fichte, Hegel and Jung. The latter postulated the two subsystems Ego and Self and associated the conscious functions of the Ego with the intellect, the capacity for rational thought, and the Self with the mind, which also includes the emotional feelings. For the harmonic development and self-realization of man the functions of both systems in complementary interaction are required. Therefore, the current overaccentuation of the intellect and of progress directed technical-scientific thinking should be corrected by making better use of the much neglected functions of the right hemisphere.

  13. Traumatic Brain Injury: Same or Different (United States)


    TRAUMATIC BRAIN INJURY : SAME OR DIFFERENT Kimberly Meyer, ACNP-BC, CNRN Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting...TITLE AND SUBTITLE Traumatic Brain Injury : Same or Different 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...official policy of the Department of the Army, Department of Defense, or U.S. Government. DISCLOSURES Nothing to disclose TRAUMATIC BRAIN INJURY Mild

  14. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with a right hemispheric lesion. (United States)

    Tanaka, Satoshi; Seki, Keiko; Hanakawa, Takashi; Harada, Madoka; Sugawara, Sho K; Sadato, Norihiro; Watanabe, Katsumi; Honda, Manabu


    The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her "mental abacus" and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex (PMd) and inferior parietal lobule (IPL). Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca's area and the left dorsolateral prefrontal and IPLs, to the visuospatial-related brain areas including the left superior parietal lobule (SPL), according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral SPL, and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery. This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case "abacus-based acalculia." Together with previous neuroimaging studies, the present result suggests an important role for the PMd and parietal cortex in the superior arithmetic ability of abacus users.

  15. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with the right hemispheric lesion

    Directory of Open Access Journals (Sweden)

    Satoshi eTanaka


    Full Text Available The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her mental abacus and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex and inferior parietal lobule.Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca’s area and the left dorsolateral prefrontal and inferior parietal lobules, to the visuospatial-related brain areas including the left superior parietal lobule, according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral superior parietal lobule and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery.This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case abacus-based acalculia. Together with previous neuroimaging studies, the present result suggests an important role for the dorsal premotor cortex and parietal cortex in the superior arithmetic ability of

  16. [Transcranial magnetic electro-stimulation with alternate action on brain hemispheres in the correction of cerebral disturbances in children with diabetes mellitus type 1]. (United States)

    Filina, N Iu; Bolotova, N V; Raĭgorodskiĭ, Iu M; Nikolaeva, N V


    Correction of psychoemotional and autonomic disturbances in children 7-17 years old with diabetes mellitus type 1 was conducted using transcranial magnetic electro-stimulation with alternate action on brain hemispheres (main group, 42 patients). The method includes the combined action of magnetic field pulses and series of electric impulses; magnetic and electric stimulation were performed synchronously - at first, on one brain hemisphere, then on another hemisphere with alternation frequency 9.5-10.5 Hz. A comparison group consisted of 44 patients with diabetes mellitus type 1 who received physiotherapeutic treatment as a combination of transcranial magnetic therapy and electro-stimulation with simultaneous action on both brain hemispheres. Treatment duration was 10 sessions. Treatment efficacy was assessed by the decrease in frequency and intensity of complaints, improvement of patient's health status measured (a scale for assessment of activity, health perception and mood) and improvement of the status of the autonomic nervous system (Vein's questionnaire), mental sphere (the Luscher color test) and cognitive traits (The Concentrated Attention Test of the Toulouse-Pierron Factorial Battery). The status of the autonomic nervous system was evaluated before and after the treatment using cardiointervalography. Brain bioelectrical activity was assessed using encephalography. Significant reduction of autonomic, psychoemotional and cognitive disturbances, normalization of brain bioelectrical activity due to the α-rhythm organization and arrhythmia removal were identified in the main group after the treatment. No adverse effects of this physiotherapeutic treatment was found.

  17. Hemispheric differences in the response of the upper atmosphere to the August 2011 geomagnetic storm: A simulation study (United States)

    Yiğit, Erdal; Frey, Harald U.; Moldwin, Mark B.; Immel, Thomas J.; Ridley, Aaron J.


    Using a three-dimensional nonhydrostatic general circulation model, we investigate the response of the thermosphere-ionosphere system to the 5-6 August 2011 major geomagnetic storm. The model is driven by measured storm-time input data of the Interplanetary Magnetic Field (IMF), solar activity, and auroral activity. Simulations for quiet steady conditions over the same period are performed as well in order to assess the response of the neutral and plasma parameters to the storm. During the storm, the high-latitude mean ion flows are enhanced by up to 150-180%. Largest ion flows are found in the main phase of the storm. Overall, the global mean neutral temperature increases by up to 15%, while the maximum thermal response is higher in the winter Southern Hemisphere at high-latitudes than the summer Northern Hemisphere: 40% vs. 20% increase in high-latitude mean temperature, respectively. The global mean Joule heating increases by more than a factor of three. There are distinct hemispheric differences in the magnitude and morphology of the horizontal ion flows and thermospheric flows during the different phases of the storm. The largest hemispheric difference in the thermospheric circulation is found during the main and recovery phases of the storm, demonstrating appreciable geographical variations. The advective forcing is found to contribute to the modeled hemispheric differences.

  18. Left Hemispheric Imbalance and Reward Mechanisms Affect Gambling Behavior: The Contribution of the Metacognition and Cortical Brain Oscillations. (United States)

    Balconi, Michela; Finocchiaro, Roberta; Canavesio, Ylenia


    The present research used the Iowa Gambling Task to test the effect of the reward-sensitivity Behavioral Activation System-Reward (BAS-Reward) construct on the ability to distinguish between high- and low-risk decisions. To elucidate the individual differences that influence the decisional processes, making the strategies more or less advantageous, we considered the impact of the BAS motivational system and the frontal left and right cortical activity on subjects' decisions. More specifically, the lateralization effect, which is related to the increased activation of the left (BAS-Reward-related) hemisphere, was explored by using frequency band analysis. Specifically, behavioral responses (gain/loss options), metacognition, and delta, theta, alpha, and beta band modulation (asymmetry index) were considered. Thirty subjects were divided into high-BAS and low-BAS groups. In comparison with low-BAS, the high-BAS group showed an increased tendency to opt in favor of the immediate reward (losing strategy) instead of the long-term option (winning strategy), and members of this group were more impaired in metacognitive monitoring of their strategies and showed an increased left hemisphere activation when they responded to losing choices. A "reward bias" effect was hypothesized to act for high BAS, based on a left-hemisphere hyperactivation.

  19. Technique of stepwise intracranial decompression combined with external ventricular drainage catheters improve the prognosis of acute post-traumatic hemispheric brain swelling patients

    Directory of Open Access Journals (Sweden)

    Lei eShi


    Full Text Available Background: Acute post-traumatic cerebral hemispheric brain swelling (ACHS is a serious disorder that occurs after traumatic brain injury (TBI, and it often requires immediate treatment. The aim of our clinical study was to assess the effects of stepwise intracranial decompression combined with external ventricular drainage catheters on the prognosis of ACHS patients.Methods: A retrospective study was performed on 172 cases of severe craniocerebral trauma patients with acute cerebral hemispheric swelling. The patients were divided into two groups: unilateral stepwise standard large trauma craniectomy (S-SLTC combined with external ventricular drainage (EVD catheter implants (n = 86 and unilateral routine frontal temporal parietal SLTC (control group, n = 86.Result: No significant differences in age, sex, or preoperative Glasgow Coma Scale score were observed between groups (P < 0.05. There were no significant differences in the ipsilateral subdural effusion incidence rates between the S-SLTC+EVD treatment group and the routine SLTC group. However, the incidence rates of intraoperative acute encephalocele and contralateral epidural and subdural hematoma in the S-SLTC+EVD group were significantly lower than those in the SLTC group (17.4% and 3.5% vs. 37.2% and 23.3%, respectively. The mean intracranial pressure (ICP values of patients in the S-SLTC+EVD group were also lower than those in the SLTC group at days 1 through7 (P<0.05. A positive neurological outcome (GOS score 4 to 5, 50.0% and decreased mortality (15.1% was observed in the S-SLTC+EVD group compared to the neurological outcome (GOS score 4 to 5, 33.8%; 36.0% in the SLTC group (P<0.05.Conclusions: Our data suggest that S-SLTC+EVD is more effective for controlling ICP, improving neurological outcome, and decreasing mortality rate compared with routine SLTC.

  20. Attention modulates hemispheric differences in functional connectivity: Evidence from MEG recordings

    NARCIS (Netherlands)

    L. Gootjes (Liselotte); A. Bouma (Anke); J.W. van Strien (Jan); P. Scheltens (Philip); C.J. Stam


    textabstractThe present study examined intrahemispheric functional connectivity during rest and dichotic listening in 8 male and 9 female healthy young adults measured with magnetoencephalography (MEG). Generalized synchronization within the separate hemispheres was estimated by means of the synchro

  1. Northern Hemisphere midlatitude cyclone variability in GCM simulations with different ocean representations

    Energy Technology Data Exchange (ETDEWEB)

    Raible, C.C. [Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Blender, R. [Meteorologisches Institut, Universitaet Hamburg, Bundesstrasse 55, 20146 Hamburg (Germany)


    The impact of different ocean models or sea surface temperature (SST) and sea-ice concentrations on cyclone tracks in the Northern Hemisphere midlatitudes is determined within a hierarchy of model simulations. A reference simulation with the coupled atmosphere ocean circulation model ECHAM/HOPE is compared with simulations using ECHAM and three simplified ocean and sea-ice representations: (1) a variable depth mixed layer (ML) ocean, (2) forcing by varying SST and sea-ice, and (3) with climatological SST and sea-ice; the latter two are from the coupled ECHAM/HOPE integration. The reference simulation reproduces the observed cyclone tracks. The cyclones are tracked automatically by a standard routine and the variability of individual cyclone trajectories within the storm tracks is determined by a cluster approach. In the forced simulation with varying SST, the geographical distribution and the statistics of the cyclones are not altered compared to the coupled reference simulation. In the ML- and the climatological simulation, deviations of the mean cyclone distribution are found which occur mainly in the North Pacific, and can partially be traced back to missing El Nino/Southern Oscillation (ENSO) variability. The climatological experiment is superior to the ML-experiment. The variability of the individual cyclone trajectories, as determined by the cluster analysis, reveals the same types and frequencies of propagation directions for all four representations of the lower boundary. The largest discrepancies for the cluster occupations are found for the climatological and the ML-simulation. (orig.)

  2. The Direction of Hemispheric Asymmetries for Object Categorization at Different Levels of Abstraction Depends on the Task (United States)

    Studer, Tobias; Hubner, Ronald


    In this study hemispheric asymmetries for categorizing objects at the basic versus subordinate level of abstraction were investigated. As predictions derived from different theoretical approaches are contradictory and experimental evidence is inconclusive in this regard, we conducted two categorization experiments, where we contrasted two…

  3. The Fault Lies on the Other Side: Altered Brain Functional Connectivity in Psychiatric Disorders is Mainly Caused by Counterpart Regions in the Opposite Hemisphere. (United States)

    Zhang, Jie; Kendrick, Keith M; Lu, Guangming; Feng, Jianfeng


    Many psychiatric disorders are associated with abnormal resting-state functional connectivity between pairs of brain regions, although it remains unclear whether the fault resides within the pair of regions themselves or other regions connected to them. Identifying the source of dysfunction is crucial for understanding the etiology of different disorders. Using pathway- and network-based techniques to analyze resting-state functional magnetic imaging data from a large population of patients with attention deficit hyperactivity disorder (239 patients, 251 controls), major depression (39 patients, 37 controls), and schizophrenia (69 patients, 62 controls), we show for the first time that only network-based cross-correlation identifies significant functional connectivity changes in all 3 disorders which survive correction. This demonstrates that the primary source of dysfunction resides not in the regional pairs themselves but in their external connections. Combining pathway and network-based functional-connectivity analysis, we established that, in all 3 disorders, the counterparts of pairs of regions in the opposite hemisphere contribute 60-76% to altered functional connectivity, compared with only 17-21% from the regions themselves. Thus, a transdiagnostic feature is of abnormal functional connectivity between brain regions produced via their contralateral counterparts. Our results demonstrate an important role for contralateral counterpart regions in contributing to altered regional connectivity in psychiatric disorders.

  4. Gender Differences in the Relationship between Emotional Intelligence and Right Hemisphere Lateralization for Facial Processing (United States)

    Castro-Schilo, Laura; Kee, Daniel W.


    The present study examined relationships between emotional intelligence, measured by the Mayer-Salovey-Caruso Emotional Intelligence Test, and right hemisphere dominance for a free vision chimeric face test. A sample of 122 ethnically diverse college students participated and completed online versions of the forenamed tests. A hierarchical…

  5. Lexical Competition is Enhanced in the Left Hemisphere: Evidence from Different Types of Orthographic Neighbors (United States)

    Perea, Manuel; Acha, Joana; Fraga, Isabel


    Two divided visual field lexical decision experiments were conducted to examine the role of the cerebral hemispheres in orthographic neighborhood effects. In Experiment 1, we employed two types of words: words with many substitution neighbors (high-"N") and words with few substitution neighbors (low-"N"). Results showed a facilitative effect of…

  6. Keck II Observations of Hemispherical Differences in H2O2 on Europa

    CERN Document Server

    Hand, Kevin P; 10.1088/2041-8205/766/2/L21


    We present results from Keck II observations of Europa over four consecutive nights using the near-infrared spectrograph (NIRSPEC). Spectra were collected in the 3.14--4.0 micron range, allowing detection and monitoring of the 3.5 micron feature due to hydrogen peroxide. Galileo Near-Infrared Spectrometer (NIMS) results first revealed hydrogen peroxide on Europa in the anti-jovian region of the leading hemisphere at an abundance of 0.13+/-0.07% by number abundance relative to water. We find comparable results for the two nights over which we observed the leading hemisphere. Significantly, we observed a small amount of hydrogen peroxide (~0.04%) during observations of Europa's anti- and sub-Jovian hemispheres. Almost no hydrogen peroxide was detected during observations of just the trailing hemisphere. We conclude that the Galileo observations likely represent the maximum hydrogen peroxide concentration, the exception potentially being the cold water ice regions of the poles, which are not readily observable f...

  7. The influence of prenatal sex hormones on development of brain lateralisation and cognitive performance

    NARCIS (Netherlands)

    Beking, Tess; Geuze, Reint; Kreukels, Baudewijntje P. C.; Groothuis, Ton


    Brain lateralisation is the functional specialization of the brain, with some functions performed primarily by the left hemisphere, and others by the right hemisphere. Lateralisation differs in strength and direction between individuals, and among tasks within individuals, potentially affecting cogn

  8. Imaging Study Confirms Brain Differences in People with ADHD (United States)

    ... Imaging Study Confirms Brain Differences in People With ADHD Attention-deficit/hyperactivity should be considered a brain ... Researchers who pinpointed brain differences in people with attention-deficit/hyperactivity disorder (ADHD) say their findings show the condition should ...

  9. Morphological brain differences between adult stutterers and non-stutterers

    Directory of Open Access Journals (Sweden)

    Hänggi Jürgen


    Full Text Available Abstract Background The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. Methods Adults with PDS (n = 10 and controls (n = 10 matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM the brains of stutterers and non-stutterers were compared with respect to white matter (WM and grey matter (GM differences. Results We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale, the inferior frontal gyrus (including the pars triangularis, the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. Conclusions These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question.

  10. Hemispheric Differences in the Response of the Upper Atmosphere to the August 2011 Geomagnetic Storm: A Simulation Study

    CERN Document Server

    Yiğit, Erdal; Moldwin, Mark B; Immel, Thomas J; Ridley, Aaron J


    Using a three-dimensional nonhydrostatic general circulation model, we investigate the response of the thermosphere-ionosphere system to the 5-6 August 2011 major geomagnetic storm. The model is driven by measured storm-time input data of the Interplanetary Magnetic Field (IMF), solar activity, and auroral activity. Simulations for quiet steady conditions over the same period are performed as well in order to assess the response of the neutral and plasma parameters to the storm. During the storm, the high-latitude mean ion flows are enhanced by up to 150-180%. Largest ion flows are found in the main phase of the storm. Overall, the global mean neutral temperature increases by up to 15%, while the maximum thermal response is higher in the winter Southern Hemisphere at high-latitudes than the summer Northern Hemisphere: 40% vs. 20%increase in high-latitude mean temperature, respectively. The global mean Joule heating increases by more than a factor of three. There are distinct hemispheric differences in the mag...

  11. [Correlations of activity of neurons of sensorimotor cortex of the right and left brain hemispheres of rabbits during defensive dominant and "animal hypnosis"]. (United States)

    Bogdanov, A V; Galashina, A G; Karamysheva, N N


    A hidden excitation focus of the rhythmic nature (a rhythmic defensive dominant focus) was produced in the rabbit's CNS. The focus was formed by means of threshold electrodermal stimulation of the left forelimb by series of pulses consisting of 15-20 stimuli with 2 s intervals between the pulses. Correlated activity of cells in the sensorimotor cortex of the right and left brain hemispheres was analyzed. In cases when crosscorrelation histograms were constructed by the results of the analysis of discharges of the left-side cortical of neurons regarding high- and middle-amplitude pulses in a right hemisphere, 15 and 23 % of correlated neural pairs, respectively, revealed the prevalence of the rhythm identical or close to the initial rhythm of stimulation that formed the hidden excitation focus. In contrast, in cases when the same analysis was applied to the right-side cortical neurons regarding high- and middle-amplitude discharges in the left hemisphere, prevalence of the dominant 2-second rhythm was revealed in correlated activity of only 3 and 10% of neural pairs, respectively. After the exposure to "animal hypnosis" procedure, the distinctions between the brain in this parameter were eliminated.

  12. Differential hemispheric modulation of preparatory attention. (United States)

    Fernández, Laura Gabriela; Siéroff, Eric


    Preparatory attention (PA) is the ability to allocate attention to a stimulus prior to its occurrence and is a crucial component of attentional control. We investigated the role of brain hemispheres in PA using an experimental test in which normal participants responded to a target that could appear in the right or the left visual fields, thus projecting to the left or the right hemispheres, while ignoring a central distractor that could appear in the preparatory phase preceding the target. This experimental test measures the ability of participants to modulate PA directed to a target location when the probability of a distractor occurrence varies across three blocks of trials (0%, 33%, 67%). The competition between distractors and target for PA should produce slower response times when the probability of distractors is high. Three experiments were conducted varying the temporal predictability of the target occurrence within a trial (high predictability in Experiments 1 and 3, and low predictability in Experiment 2), and the task used (location in Experiments 1 and 2, and detection in Experiment 3). We found that the modulation of PA by the expected probability of events was different in each visual field/hemisphere. Whereas the left hemisphere PA was influenced by the mere probability of events in each block of trials, the right hemisphere PA was mainly influenced by events with high temporal predictability. These results suggest that each hemisphere uses a different strategy to modulate PA when directed to a target location at the perceptual level of visual processing.

  13. When one hemisphere takes control: metacontrol in pigeons (Columba livia.

    Directory of Open Access Journals (Sweden)

    Ruth Adam

    Full Text Available BACKGROUND: Vertebrate brains are composed of two hemispheres that receive input, compute, and interact to form a unified response. How the partially different processes of both hemispheres are integrated to create a single output is largely unknown. In some cases one hemisphere takes charge of the response selection--a process known as metacontrol. Thus far, this phenomenon has only been shown in a handful of studies with primates, mostly conducted in humans. Metacontrol, however, is even more relevant for animals like birds with laterally placed eyes and complete chiasmatic decussation since visual input to the hemispheres is largely different. METHODOLOGY/PRINCIPAL FINDINGS: Homing pigeons (Columba livia were trained with a color discrimination task. Each hemisphere was trained with a different color pair and therefore had a different experience. Subsequently, the pigeons were binocularly examined with two additional stimuli that combined the positive color of one hemisphere with a negative color that had been shown to the other, omitting the availability of a coherent solution and confronting the pigeons with a conflicting situation. Some of the pigeons responded to both stimuli, indicating that none of the hemispheres dominated the overall preference. Some birds, however, responded primarily to one of the conflicting stimuli, showing that they based their choice on the left- or right-monocularly learned color pair, indicating hemispheric metacontrol. CONCLUSIONS/SIGNIFICANCE: We could demonstrate for the first time that metacontrol is a widespread phenomenon that also exists in birds, and thus in principle requires no corpus callosum. Our results are closely similar to those in humans: monocular performance was higher than binocular one and animals displayed different modes of hemispheric dominance. Thus, metacontrol is a dynamic and widely distributed process that possibly constitutes a requirement for all animals with a bipartite brain to

  14. A straight nasal septum and right unilateral hypertrophied inferior nasal turbinate, a very rare anatomical phenomenon, in skilled language translators: relevance to anomalous dominance, brain hemisphericity and second language acquisition. (United States)

    Backon, J; Negeris, B; Kurzon, D; Amit-Chochavi, H


    Research on second language acquisition has recently focused on the concept of brain hemisphericity. Since the nasal cycle indexes brain hemisphericity and a deviated nasal septum itself affected by structural brain dominance may prevent nasal cycling, we investigated the presence of septal deviation and inferior turbinate hypertrophy in 11 expert translators. We found that 10 of the 11 subjects demonstrated both a straight nasal septum and right unilateral inferior turbinate hypertrophy, an extremely rare anatomical phenomenon. The one-tailed binomial test was extremely significant (p < .0000001). This anatomical phenomenon, which can be noninvasively checked in less than 30 seconds may predict excellence in second language acquisition.

  15. Encephalometry on the medial face of the human brain hemisphere: a necropsy study Encefalometria na face medial do hemisfério cerebral humano: estudo em necropsias

    Directory of Open Access Journals (Sweden)

    Paula J. Ribeiro


    Full Text Available This study aims to evaluate the dimensions of the human brain, specifically in the frontal cortex, helping the analysis of neuroimaging. A form was made to register and describe encephalic measurements and 81 cerebral hemispheres (CH were analyzed. Male individuals showed larger CH length; wider superior frontal gyrus in the right CH; bigger encephalic weight and corpus callosum (CC width. The proportion of measurement from the frontal pole to the most anterior part of the CC genu, related to the CH length gets smaller with aging, whereas the average distance from the most posterior part of the splenum of the CC to the occipital pole was bigger in both male CHs and there was a tendency of decrease in this difference with aging.Este estudo visa avaliar as dimensões do cérebro humano, particularmente do córtex frontal, podendo colaborar para as análises de neuroimagem. Foi elaborado um formulário para registro e descrição das medidas encefálicas. A amostra foi constituída por 81 hemisférios cerebrais (HC adultos. Os homens apresentaram maior comprimento do HC; giro frontal superior mais largo no HC direito; maior peso encefálico e largura do corpo caloso (CC. A proporção da medida do pólo frontal à parte mais anterior do joelho do CC, em relação ao comprimento do HC diminui com o avanço da idade. Já a da média da distância da parte mais posterior do esplênio do CC ao pólo occipital foi maior em ambos HC dos homens e houve tendência à diminuição desta proporção com o avanço da idade.

  16. Does brain injury impair speech and gesture differently?

    Directory of Open Access Journals (Sweden)

    Tilbe Göksun


    Full Text Available People often use spontaneous gestures when talking about space, such as when giving directions. In a recent study from our lab, we examined whether focal brain-injured individuals’ naming motion event components of manner and path (represented in English by verbs and prepositions, respectively are impaired selectively, and whether gestures compensate for impairment in speech. Left or right hemisphere damaged patients and elderly control participants were asked to describe motion events (e.g., walking around depicted in brief videos. Results suggest that producing verbs and prepositions can be separately impaired in the left hemisphere and gesture production compensates for naming impairments when damage involves specific areas in the left temporal cortex.

  17. Detection of misery perfusion in the cerebral hemisphere with chronic unilateral major cerebral artery steno-occlusive disease using crossed cerebellar hypoperfusion: comparison of brain SPECT and PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Yoshiyasu; Ogasawara, Kuniaki; Saito, Hideo; Takahashi, Yoshihiro; Ogasawara, Yasushi; Kobayashi, Masakazu; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Terasaki, Kazunori [Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Yoshida, Kenji; Beppu, Takaaki; Kubo, Yoshitaka; Fujiwara, Shunrou [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Tsushima, Eiki [Hirosaki University, Graduate School of Health Sciences, Hirosaki (Japan)


    In patients with unilateral internal carotid or middle cerebral artery (ICA or MCA) occlusive disease, the degree of crossed cerebellar hypoperfusion that is evident within a few months after the onset of stroke may reflect cerebral metabolic rate of oxygen in the affected cerebral hemisphere relative to that in the contralateral cerebral hemisphere. The aim of the present study was to determine whether the ratio of blood flow asymmetry in the cerebellar hemisphere to blood flow asymmetry in the cerebral hemisphere on positron emission tomography (PET) and single photon emission computed tomography (SPECT) correlates with oxygen extraction fraction (OEF) asymmetry in the cerebral hemisphere on PET in patients with chronic unilateral ICA or MCA occlusive disease and whether this blood flow ratio on SPECT detects misery perfusion in the affected cerebral hemisphere in such patients. Brain blood flow and OEF were assessed using {sup 15}O-PET and N-isopropyl-p-[{sup 123}I]iodoamphetamine ({sup 123}I-IMP) SPECT, respectively. All images were anatomically standardized using SPM2. A region of interest (ROI) was automatically placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres using a three-dimensional stereotaxic ROI template, and affected-to-contralateral asymmetry in the MCA territory or contralateral-to-affected asymmetry in the cerebellar hemisphere was calculated. Sixty-three patients with reduced blood flow in the affected cerebral hemisphere on {sup 123}I-IMP SPECT were enrolled in this study. A significant correlation was observed between MCA ROI asymmetry of PET OEF and the ratio of cerebellar hemisphere asymmetry of blood flow to MCA ROI asymmetry of blood flow on PET (r = 0.381, p = 0.0019) or SPECT (r = 0.459, p = 0.0001). The correlation coefficient was higher when reanalyzed in a subgroup of 43 patients undergoing a PET study within 3 months after the last ischemic event (r = 0.541, p = 0.0001 for PET; r = 0.609, p < 0

  18. Unilateral Hemispheric Encephalitis

    Directory of Open Access Journals (Sweden)

    Mohan Leslie Noone


    Full Text Available A 10 year old boy presented with history of mild fever and upper respiratory symptoms followed by recurrent seizures and loss of consciousness on the next day. Normal blood counts and abnormal hepatic transaminases were noted. MRI of the brain, done on the fourth day of illness, showed extensive involvement of the cortex in the right hemisphere. Lumbar CSF was normal. The EEG showed bilateral slowing with frontal sharp wave discharges and marked attenuation over the entire right hemisphere. The patient succumbed to the illness on the ninth day. A similar pattern of acute unilateral hemispheric cortical involvement is described in the hemiconvulsion-hemiplegia-epilepsy (HHE syndrome, which is typically described to occur in children below 4 years of age. This case of fulminant acute unilateral encaphilitic illness could represent the acute phase of HHE syndrome.

  19. Right hemisphere grey matter structure and language outcomes in chronic left hemisphere stroke. (United States)

    Xing, Shihui; Lacey, Elizabeth H; Skipper-Kallal, Laura M; Jiang, Xiong; Harris-Love, Michelle L; Zeng, Jinsheng; Turkeltaub, Peter E


    The neural mechanisms underlying recovery of language after left hemisphere stroke remain elusive. Although older evidence suggested that right hemisphere language homologues compensate for damage in left hemisphere language areas, the current prevailing theory suggests that right hemisphere engagement is ineffective or even maladaptive. Using a novel combination of support vector regression-based lesion-symptom mapping and voxel-based morphometry, we aimed to determine whether local grey matter volume in the right hemisphere independently contributes to aphasia outcomes after chronic left hemisphere stroke. Thirty-two left hemisphere stroke survivors with aphasia underwent language assessment with the Western Aphasia Battery-Revised and tests of other cognitive domains. High-resolution T1-weighted images were obtained in aphasia patients and 30 demographically matched healthy controls. Support vector regression-based multivariate lesion-symptom mapping was used to identify critical language areas in the left hemisphere and then to quantify each stroke survivor's lesion burden in these areas. After controlling for these direct effects of the stroke on language, voxel-based morphometry was then used to determine whether local grey matter volumes in the right hemisphere explained additional variance in language outcomes. In brain areas in which grey matter volumes related to language outcomes, we then compared grey matter volumes in patients and healthy controls to assess post-stroke plasticity. Lesion-symptom mapping showed that specific left hemisphere regions related to different language abilities. After controlling for lesion burden in these areas, lesion size, and demographic factors, grey matter volumes in parts of the right temporoparietal cortex positively related to spontaneous speech, naming, and repetition scores. Examining whether domain general cognitive functions might explain these relationships, partial correlations demonstrated that grey matter

  20. Right Hemisphere Dominance in Visual Statistical Learning (United States)

    Roser, Matthew E.; Fiser, Jozsef; Aslin, Richard N.; Gazzaniga, Michael S.


    Several studies report a right hemisphere advantage for visuospatial integration and a left hemisphere advantage for inferring conceptual knowledge from patterns of covariation. The present study examined hemispheric asymmetry in the implicit learning of new visual feature combinations. A split-brain patient and normal control participants viewed…

  1. Mapping different intra-hemispheric parietal-motor networks using twin Coil TMS

    DEFF Research Database (Denmark)

    Karabanov, Anke Ninija; Chao, Chi-Chao; Paine, Rainer


    Accumulating evidence suggests anatomical and functional differences in connectivity between the anterior and posterior parts of the inferior-parietal lobule (IPL) and the frontal motor areas.......Accumulating evidence suggests anatomical and functional differences in connectivity between the anterior and posterior parts of the inferior-parietal lobule (IPL) and the frontal motor areas....

  2. Cross-language differences in the brain network subserving intelligible speech. (United States)

    Ge, Jianqiao; Peng, Gang; Lyu, Bingjiang; Wang, Yi; Zhuo, Yan; Niu, Zhendong; Tan, Li Hai; Leff, Alexander P; Gao, Jia-Hong


    How is language processed in the brain by native speakers of different languages? Is there one brain system for all languages or are different languages subserved by different brain systems? The first view emphasizes commonality, whereas the second emphasizes specificity. We investigated the cortical dynamics involved in processing two very diverse languages: a tonal language (Chinese) and a nontonal language (English). We used functional MRI and dynamic causal modeling analysis to compute and compare brain network models exhaustively with all possible connections among nodes of language regions in temporal and frontal cortex and found that the information flow from the posterior to anterior portions of the temporal cortex was commonly shared by Chinese and English speakers during speech comprehension, whereas the inferior frontal gyrus received neural signals from the left posterior portion of the temporal cortex in English speakers and from the bilateral anterior portion of the temporal cortex in Chinese speakers. Our results revealed that, although speech processing is largely carried out in the common left hemisphere classical language areas (Broca's and Wernicke's areas) and anterior temporal cortex, speech comprehension across different language groups depends on how these brain regions interact with each other. Moreover, the right anterior temporal cortex, which is crucial for tone processing, is equally important as its left homolog, the left anterior temporal cortex, in modulating the cortical dynamics in tone language comprehension. The current study pinpoints the importance of the bilateral anterior temporal cortex in language comprehension that is downplayed or even ignored by popular contemporary models of speech comprehension.

  3. The Architecture of Cross-Hemispheric Communication in the Aging Brain: Linking Behavior to Functional and Structural Connectivity (United States)

    Kragel, James E.; Madden, David J.; Cabeza, Roberto


    Contralateral recruitment remains a controversial phenomenon in both the clinical and normative populations. To investigate the neural correlates of this phenomenon, we explored the tendency for older adults to recruit prefrontal cortex (PFC) regions contralateral to those most active in younger adults. Participants were scanned with diffusion tensor imaging and functional magnetic rresonance imaging during a lateralized word matching task (unilateral vs. bilateral). Cross-hemispheric communication was measured behaviorally as greater accuracy for bilateral than unilateral trials (bilateral processing advantage [BPA]) and at the neural level by functional and structural connectivity between contralateral PFC. Compared with the young, older adults exhibited 1) greater BPAs in the behavioral task, 2) greater compensatory activity in contralateral PFC during the bilateral condition, 3) greater functional connectivity between contralateral PFC during bilateral trials, and 4) a positive correlation between fractional anisotropy in the corpus callosum and both the BPA and the functional connectivity between contralateral PFC, indicating that older adults' ability to distribute processing across hemispheres is constrained by white matter integrity. These results clarify how older adults’ ability to recruit extra regions in response to the demands of aging is mediated by existing structural architecture, and how this architecture engenders corresponding functional changes that allow subjects to meet those task demands. PMID:21653286

  4. The Lateralizer: A Tool for Students to Explore the Divided Brain (United States)

    Motz, Benjamin A.; James, Karin H.; Busey, Thomas A.


    Despite a profusion of popular misinformation about the left brain and right brain, there are functional differences between the left and right cerebral hemispheres in humans. Evidence from split-brain patients, individuals with unilateral brain damage, and neuroimaging studies suggest that each hemisphere may be specialized for certain cognitive…

  5. Differential Hemispheric Processing in the Recognition of Chinese Characters with Different Structures in Foveal and Parafoveal Vision

    Directory of Open Access Journals (Sweden)

    Janet H. Hsiao


    Full Text Available Whether foveal representation in reading is initially split and contralaterally projected to different hemispheres or bilaterally projected remains a controversial issue. Here we examine visual field asymmetry effects in naming Chinese characters with different structures, with characters presented either to the left visual field or the right visual field (RVF, and either within or outside foveal vision (eccentricity. We show that overall the RVF advantage in naming characters was significant in both eccentricity conditions (fovea vs. parafovea, with a stronger effect in parafoveal vision. This suggests that foveal splitting may not be an all-or-none phenomenon but has a graded effect. When examining characters with different structures separately, this interaction between visual field and eccentricity was significant only in the dominant, right-heavy character structure type, but not in the minority left-heavy or symmetric structure types, suggesting a modulation of character structure or type frequency on the eccentricity effect. In addition, existence of a phonetic radical modulated the visual field asymmetry effect differentially in different character structure types; however this effect did not interact with eccentricity. This result thus suggests that character structure and existence of a phonetic radical have differential modulation on character processing in the foveal and parafoveal vision.

  6. Gender differences in brain networks supporting empathy. (United States)

    Schulte-Rüther, Martin; Markowitsch, Hans J; Shah, N Jon; Fink, Gereon R; Piefke, Martina


    Females frequently score higher on standard tests of empathy, social sensitivity, and emotion recognition than do males. It remains to be clarified, however, whether these gender differences are associated with gender specific neural mechanisms of emotional social cognition. We investigated gender differences in an emotion attribution task using functional magnetic resonance imaging. Subjects either focused on their own emotional response to emotion expressing faces (SELF-task) or evaluated the emotional state expressed by the faces (OTHER-task). Behaviorally, females rated SELF-related emotions significantly stronger than males. Across the sexes, SELF- and OTHER-related processing of facial expressions activated a network of medial and lateral prefrontal, temporal, and parietal brain regions involved in emotional perspective taking. During SELF-related processing, females recruited the right inferior frontal cortex and superior temporal sulcus stronger than males. In contrast, there was increased neural activity in the left temporoparietal junction in males (relative to females). When performing the OTHER-task, females showed increased activation of the right inferior frontal cortex while there were no differential activations in males. The data suggest that females recruit areas containing mirror neurons to a higher degree than males during both SELF- and OTHER-related processing in empathic face-to-face interactions. This may underlie facilitated emotional "contagion" in females. Together with the observation that males differentially rely on the left temporoparietal junction (an area mediating the distinction between the SELF and OTHERS) the data suggest that females and males rely on different strategies when assessing their own emotions in response to other people.

  7. Energies and wave functions of an off-centre donor in hemispherical quantum dot: Two-dimensional finite difference approach and ritz variational principle

    Energy Technology Data Exchange (ETDEWEB)

    Nakra Mohajer, Soukaina; El Harouny, El Hassan [Laboratoire de Physique de la Matière Condensée, Département de Physique, Faculté des Sciences, Université Abdelmalek Essaadi, B.P. 2121 M’Hannech II, 93030 Tétouan (Morocco); Ibral, Asmaa [Equipe d’Optique et Electronique du Solide, Département de Physique, Faculté des Sciences, Université Chouaïb Doukkali, B. P. 20 El Jadida Principale, El Jadida (Morocco); Laboratoire d’Instrumentation, Mesure et Contrôle, Département de Physique, Faculté des Sciences, Université Chouaïb Doukkali, B. P. 20 El Jadida Principale, El Jadida (Morocco); El Khamkhami, Jamal [Laboratoire de Physique de la Matière Condensée, Département de Physique, Faculté des Sciences, Université Abdelmalek Essaadi, B.P. 2121 M’Hannech II, 93030 Tétouan (Morocco); and others


    Eigenvalues equation solutions of a hydrogen-like donor impurity, confined in a hemispherical quantum dot deposited on a wetting layer and capped by an insulating matrix, are determined in the framework of the effective mass approximation. Conduction band alignments at interfaces between quantum dot and surrounding materials are described by infinite height barriers. Ground and excited states energies and wave functions are determined analytically and via one-dimensional finite difference approach in case of an on-center donor. Donor impurity is then moved from center to pole of hemispherical quantum dot and eigenvalues equation is solved via Ritz variational principle, using a trial wave function where Coulomb attraction between electron and ionized donor is taken into account, and by two-dimensional finite difference approach. Numerical codes developed enable access to variations of donor total energy, binding energy, Coulomb correlation parameter, spatial extension and radial probability density with respect to hemisphere radius and impurity position inside the quantum dot.

  8. The influence of sex hormones on brain lateralisation

    NARCIS (Netherlands)

    Beking, Tess; Geuze, Reint; Groothuis, Antonius


    Brain lateralization is the phenomenon that both hemispheres of the brain are specialised in different functions. Lateralization differs in strength and direction between individuals and among tasks within individuals, potentially affecting cognitive performance. There is debate to what extent indiv

  9. Leaf Area Index (LAI) in different type of agroforestry systems based on hemispherical photographs in Cidanau Watershed (United States)

    Nur Khairiah, Rahmi; Setiawan, Yudi; Budi Prasetyo, Lilik; Ayu Permatasari, Prita


    Ecological functions of agroforestry systems have perceived benefit to people around Cidanau Watershed, especially in the protection of water quality. The main causes of the problems encountered in the Cidanau Watershed are associated with the human factors, especially encroachment and conversion of forest into farmland. The encroachment has made most forest in Cidanau Watershed become bare land. To preserve the ecological function of agroforestry systems in Cidanau Watershed, monitoring of the condition of the vegetation canopy in agroforestry systems is really needed. High intensity thinning of crown density due to deforestation can change stand leaf area index dramatically. By knowing LAI, we can assess the condition of the vegetation canopy in agroforestry systems. LAI in this research was obtained from Hemispherical Photographs analysis using the threshold method in HemiView Canopy Analysis Software. Our research results indicate that there are six types of agroforestry in Cidanau Watershed i.e. Sengon Agroforestry, Clove Agroforestry, Melinjo Agroforestry, Chocolate Agroforestry, Coffee Agroforestry, and Complex Agroforestry. Several factors potentially contribute to variations in the value of LAI in different types of agroforestry. The simple assumptions about differences ranges of LAI values on six types of agroforestry is closely related to leaf area and plant population density.

  10. The response of bispectral index to laryngoscopy, comparison between hemispheres in patients with a brain tumour versus a healthy control group.

    NARCIS (Netherlands)

    Wyler, B.; Wyffels, P.; de Hert, S.; Okito, Jean Pierre Kalala; Struys, Michel; Vereecke, Hugo Eric Marc


    Background and Goal of Study: Electroencephalogram during anaesthesia may be affected by brain tumour.(1) We studied whether patients with a brain tumour have different BIS responses after laryngoscopy (LAR). We compared tumour patients with healthy control patients. Materials and Methods: After EC

  11. Hemispheric contributions to pragmatics. (United States)

    Zaidel, E; Kasher, A; Soroker, N; Batori, G; Giora, R; Graves, D


    Twenty-seven patients with right-hemisphere damage (RBD) and thirty-one patients with left-hemisphere damage (LBD) received a new pragmatics battery in Hebrew consisting of two parts: (1) comprehension and production of basic speech acts (BSAs), including tests of assertions, questions, requests, and commands, and (2) comprehension of implicatures, including implicatures of quantity, quality, relevance, and manner. Each test had a verbal and a nonverbal version. Patients also received Hebrew versions of the Western Aphasia Battery and of the Right Hemisphere Communication Battery. Both LBD and RBD patients were impaired relative to controls but did not differ from each other in their overall scores on BSAs and on Implicatures when scores were corrected by aphasia and neglect indices. There was a systematic localization of BSAs in the left hemisphere (LH) but not in the right hemisphere (RH). There was poor localization of Implicatures in either hemisphere. In LBD patients, BSAs were associated with language functions measured with the WAB, suggesting the radical possibility that the classic localization of language functions in aphasia is influenced by the localization of the BSAs required by aphasia language tests. Both BSAs and implicatures show greater functional independence from other pragmatic, language and cognitive functions in the RBD than in the LBD patients. Thus, the LH is more likely to contain an unmodular domain-nonspecific set of central cognitive mechanisms for applying means-ends rationality principles to intentional activity.

  12. Functional Magnetic Resonance Imaging of Chronic Dysarthric Speech after Childhood Brain Injury: Reliance on a Left-Hemisphere Compensatory Network (United States)

    Morgan, Angela T.; Masterton, Richard; Pigdon, Lauren; Connelly, Alan; Liegeois, Frederique J.


    Severe and persistent speech disorder, dysarthria, may be present for life after brain injury in childhood, yet the neural correlates of this chronic disorder remain elusive. Although abundant literature is available on language reorganization after lesions in childhood, little is known about the capacity of motor speech networks to reorganize…

  13. Augmenting Melodic Intonation Therapy with non-invasive brain stimulation to treat impaired left-hemisphere function: two case studies

    Directory of Open Access Journals (Sweden)

    Shahd eAl-Janabi


    Full Text Available The purpose of this study was to investigate whether or not the right hemisphere can be engaged using Melodic Intonation Therapy (MIT and excitatory repetitive transcranial magnetic stimulation (rTMS to improve language function in people with aphasia. The two participants in this study (GOE and AMC have chronic non-fluent aphasia. A functional Magnetic Resonance Imaging (fMRI task was used to localize the right Broca’s homologue area in the inferior frontal gyrus for rTMS coil placement. The treatment protocol included an rTMS phase, which consisted of 3 treatment sessions that used an excitatory stimulation method known as intermittent theta burst stimulation, and a sham-rTMS phase, which consisted of 3 treatment sessions that used a sham coil. Each treatment session was followed by 40 minutes of MIT. A linguistic battery was administered after each session. Our findings show that one participant, GOE, improved in verbal fluency and the repetition of phrases treated with MIT in combination with TMS. However, AMC showed no evidence of behavioural benefit from this brief treatment trial. Post-treatment neural activity changes were observed for both participants in the left Broca’s area and right Broca’s homologue. These case studies indicate that a combination of rTMS applied to the right Broca’s homologue and MIT has the potential to improve speech and language outcomes for at least some people with post-stroke aphasia.

  14. Sex differences in brain organization: implications for human communication. (United States)

    Hanske-Petitpierre, V; Chen, A C


    This article reviews current knowledge in two major research domains: sex differences in neuropsychophysiology, and in human communication. An attempt was made to integrate knowledge from several areas of brain research with human communication and to clarify how such a cooperative effort may be beneficial to both fields of study. By combining findings from the area of brain research, a communication paradigm was developed which contends that brain-related sex differences may reside largely in the area of communication of emotion.

  15. Long-term Trend of Cold Air Mass Amount below a Designated Potential Temperature in Northern and Southern Hemisphere Winters with 7 Different Reanalysis Datasets (United States)

    Kanno, Y.; Abdillah, M. R.; Iwasaki, T.


    This study addresses that the hemispheric total cold air mass amount defined below a threshold potential temperature of 280 K is a good indicator of the long-term trend of climate change in the polar region. We demonstrate quantitative analyses of warming trend in the Northern Hemisphere (NH) and Southern Hemisphere (SH) winters, using 7 different reanalysis datasets (JRA-55, JRA-55C, JRA-55AMIP, ERA-interim, CFSR, JRA-25, NCEP-NCAR). Hemispheric total cold air mass amount in the NH winter exhibit a statistically significant decreasing trend in all reanalysis datasets at a rate about -1.37 to -0.77% per decade over the period 1959-2012 and at a rate about -1.57 to -0.82% per decade over 1980-2012. There is no statistically significant trend in the equatorward cold air mass flux across latitude of 45N, which is an indicator for hemispheric-scale cold air outbreak, over the period 1980-2012 except for NCEP-NCAR reanalysis dataset which shows substantial decreasing trend of about -3.28% per decade. The spatial distribution of the long-term trend of cold air mass amount in the NH winter is almost consistent among reanalysis datasets except for JRA-55AMIP over the period 1980-2012. Cold air mass amount increases over Central Siberia, Kamchatka peninsula, and Bering Sea, while it decreases over Norwegian Sea, Barents Sea, Kara Sea, Greenland, Canada, Northern part of United States, and East Asia. In the SH winter, on the other hand, there is a large discrepancy in hemispheric total cold air mass amount and equatorward cold air mass flux across latitude of 50S over the period 1980-2010 among reanalysis datasets. This result indicate that there is a large uncertainty in the long-term trend of cold air mass amount in the SH winter.

  16. Sex Differences in Intelligence and Brain Size: A Developmental Theory. (United States)

    Lynn, Richard


    Proposes a developmental theory of sex differences in intelligence that states that the faster maturation and brain size growth in girls up to age 15 compensates for their smaller brain size so that sex differences in intelligence are very small. Discusses evidence that supports this theory. (SLD)

  17. Differences in lateral hemispheric asymmetries of glucose utilization between early- and late-onset Alzheimer-type dementia

    Energy Technology Data Exchange (ETDEWEB)

    Koss, E.; Friedland, R.P.; Ober, B.A.; Jagust, W.J.


    Positron emission tomography with (/sup 18/F)fluorodeoxyglucose revealed greater right than left hemispheric impairment of cortical glucose metabolism in patients with probable Alzheimer's disease who were younger than 65 but not in those over 65. This asymmetry was related to poor visuospatial performance.

  18. Hemispheric biases and the control of visuospatial attention: an ERP study

    Directory of Open Access Journals (Sweden)

    Banich Marie T


    Full Text Available Abstract Background We examined whether individual differences in hemispheric utilization can interact with the intrinsic attentional biases of the cerebral hemispheres. Evidence suggests that the hemispheres have competing biases to direct attention contralaterally, with the left hemisphere (LH having a stronger bias than the right hemisphere. There is also evidence that individuals have characteristic biases to utilize one hemisphere more than the other for processing information, which can induce a bias to direct attention to contralateral space. We predicted that LH-biased individuals would display a strong rightward attentional bias, which would create difficulty in selectively attending to target stimuli in the left visual field (LVF as compared to right in the performance of a bilateral flanker task. Results Consistent with our hypothesis, flanker interference effects were found on the N2c event-related brain potential and error rate for LH-biased individuals in the Attend-LVF condition. The error rate effect was correlated with the degree of hemispheric utilization bias for the LH-Bias group. Conclusion We conclude that hemispheric utilization bias can enhance a hemisphere's contralateral attentional bias, at least for individuals with a LH utilization bias. Hemispheric utilization bias may play an important and largely unrecognized role in visuospatial attention.

  19. Hemispheric asymmetries: The comparative view

    Directory of Open Access Journals (Sweden)

    Sebastian eOcklenburg


    Full Text Available Hemispheric asymmetries play an important role in almost all cognitive functions. For more than a century, they were considered to be uniquely human but now an increasing number of findings in all vertebrate classes make it likely that we inherited our asymmetries from common ancestors. Thus, studying animal models could provide unique insights into the mechanisms of lateralization. We outline three such avenues of research by providing an overview of experiments on left-right differences in the connectivity of sensory systems, the embryonic determinants of brain asymmetries, and the genetics of lateralization. All these lines of studies could provide a wealth of insights into our own asymmetries that should and will be exploited by future analyses.

  20. Different Coexpressions of Arthritis-Relevant Genes between Different Body Organs and Different Brain Regions in the Normal Mouse Population


    Cao, Yanhong; Huang, Yue; Wang, Lishi; Zhu, JiaQian; Gu, Weikuan


    Structural changes in different parts of the brain in rheumatoid arthritis (RA) patients have been reported. RA is not regarded as a brain disease. Body organs such as spleen and lung produce RA-relevant genes. We hypothesized that the structural changes in the brain are caused by changes of gene expression in body organs. Changes in different parts of the brain may be affected by altered gene expressions in different body organs. This study explored whether an association between gene expres...

  1. Differences in semantic category priming in the left and right cerebral hemispheres under automatic and controlled processing conditions. (United States)

    Collins, M


    The contribution of each cerebral hemisphere to the generation of semantic category meanings at automatic and strategic levels of processing was investigated in a priming experiment where prime and target words were independently projected to the left or right visual fields (LVF or RVF). Non-associated category exemplars were employed as related pairs in a lexical decision task and presented in two experimental conditions. The first condition was designed to elicit automatic processing, so related pairs comprised 20% of the positive set, stimulus pairs were temporally separated by a stimulus onset asynchrony (SOA) of 250 ms, and there was no allusion to the presence of related pairs in the instructions to subjects. The second condition, designed to invoke controlled processing, incorporated a relatedness proportion of 50%, stimulus pairs separated by an SOA of 750 ms, and instructions which informed subjects of the presence and use of category exemplar pairs in the stimulus set. In the first condition, a prime directed to either visual field facilitated responses to categorically related targets subsequently projected to the RVF, while in the second condition a prime directed to either visual field facilitated responses to related targets projected to the LVF. The facilitation effects obtained in both conditions appeared to reflect automatic processes, while strategic processes were invoked in the left, but not the right hemisphere in the second condition. The results suggest that both hemispheres have automatic access to semantic category meanings, although the timecourse of activation of semantic category meanings is slower in the right hemisphere than in the left.

  2. Hemispheric processing of differently valenced and self-relevant attachment words in middle-aged married and separated individuals. (United States)

    Fussell, Nicola J; Rowe, Angela C; Mohr, Christine


    The reliance in experimental psychology on testing undergraduate populations with relatively little life experience, and/or ambiguously valenced stimuli with varying degrees of self-relevance, may have contributed to inconsistent findings in the literature on the valence hypothesis. To control for these potential limitations, the current study assessed lateralised lexical decisions for positive and negative attachment words in 40 middle-aged male and female participants. Self-relevance was manipulated in two ways: by testing currently married compared with previously married individuals and by assessing self-relevance ratings individually for each word. Results replicated a left hemisphere advantage for lexical decisions and a processing advantage of emotional over neutral words but did not support the valence hypothesis. Positive attachment words yielded a processing advantage over neutral words in the right hemisphere, while emotional words (irrespective of valence) yielded a processing advantage over neutral words in the left hemisphere. Both self-relevance manipulations were unrelated to lateralised performance. The role of participant sex and age in emotion processing are discussed as potential modulators of the present findings.

  3. 卒中患者大脑半球语言认知N400差异性研究%Analysis of the difference of event-related potentials (ERP) N400 of language cognition in stroke patientsbetween left and right cerebral hemisphere in Chinese reading

    Institute of Scientific and Technical Information of China (English)

    韩静; 李华; 苏俊红


    目的:探讨脑卒中患者两半球语言认知N400差异性。方法:对20例首发单病灶脑卒中患者(其中左半球损伤者9例,右半球损伤者11例)和20例无脑损害的患者/健康体检者进行N400实验。比较两组N400差异波潜伏期、波幅的差异。结果:右半球损伤者较对照组Fz、Pz、T4点潜伏期延长,T4点波幅降低。右半球损伤者较左半球损伤者,Pz点潜伏期延长,反应时延长。结论:大脑右半球可能参与汉语言认知加工过程。%Objective Aimed to use event-related potentials ( ERP) N400 to explore the difference between left and right hemisphere. Methods 20 patients with single brain lesion and first episode stroke, which including 9 patients damaged at left hemisphere and 11 patients damaged at right hemisphere, and 20 normal controls were selected. They received the experiment of the N400 tests. The latency and amplitude of differential wave of N400 were compared. Results The latencies at Fz,Pz,T4 were longer and the amplitudes at T4 were lower in patients with right hemisphere lesion than in controls. The latencies at Pz and the reaction times were longer in patients with right hemisphere lesion than those with left hemisphere lesion. Conclusion The right hemisphere maybe participate in Chinese language processing.

  4. Mood disorders differ after left and right cerebral hemisphere injury%大脑左右半球损伤后情绪障碍差异的观察

    Institute of Scientific and Technical Information of China (English)

    魏英玲; 曲福玲; 段晓琴; 刘忠良; 罗媛媛; 袁望舒; 窦晓丽; 夏玲


    Objective To explore mood disorders after left and right cerebral hemisphere injury,to search for possible mechanisms and to provide the basis for designing rehabilitation protocols and assessing prognosis.Methods Fifty-one cases with brain injury were recruited from a rehabilitation center and divided into left and right hemisphere injury groups with 26 and 25 cases,respectively.Hamilton rating scale for depression (HRSD) scores were analyzed. Results The left hemisphere patients had significantly higher HRSD total scores and higher scores indicating 15 kinds of mood disorders (depression,feelings of guilt,suicidal thoughts etc.).Right hemisphere injury patients had significantly higher diurnal variation,depersonalization or derealization and paranoid symptoms. Conclusions The lateralization of the cerebral hemispheres may display itself in mood and emotion.After left or right hemisphere injury,the depression presentation is different,so treatment,prognosis assessment and psychological intervention should be different for left and right hemisphere injuries.%目的 探讨大脑左右半球损伤后情绪情感异常的不同表现、可能机制,以期能为临床上大脑损伤患者的心理及肢体功能障碍等康复治疗方案的设计、预后评价提供依据.方法 选取康复中心脑损伤患者51例,分为左侧脑半球损伤组(左脑损伤组)26例和右侧脑半球损伤组(右脑损伤组)25例,均进行汉密尔顿抑郁量表(HAMD)测试,最终对HAND总分、各分项得分及选项差异进行归纳、分析及总结.结果 左脑损伤组患者在抑郁总分及抑郁情绪、有罪感、自杀等l5个分项目方面较右脑损伤组患者得分高,差异有统计学意义(P<0.05,P<0.01).右脑损伤组患者在日夜变化、人格解体或现实解体、偏执症状等3个方面较左脑损伤组患者得分高,差异有统计学意义(P<0.05).结论 大脑半球的偏侧化效应也表现在情绪情感方面,左右两侧大脑

  5. The influence of sex hormones on brain lateralisation and cognitive performance

    NARCIS (Netherlands)

    Beking, Tess; Geuze, Reint; Groothuis, Ton; Kreukels, Baudewijntje


    Brain lateralization is the phenomenon that both hemispheres of the brain are specialised in different functions. Lateralization differs in strength and direction between individuals and among tasks within individuals, potentially affecting cognitive performance. There is debate to what extent indiv

  6. Brain function differences in language processing in children and adults with autism. (United States)

    Williams, Diane L; Cherkassky, Vladimir L; Mason, Robert A; Keller, Timothy A; Minshew, Nancy J; Just, Marcel Adam


    Comparison of brain function between children and adults with autism provides an understanding of the effects of the disorder and associated maturational differences on language processing. Functional imaging (functional magnetic resonance imaging) was used to examine brain activation and cortical synchronization during the processing of literal and ironic texts in 15 children with autism, 14 children with typical development, 13 adults with autism, and 12 adult controls. Both the children and adults with autism had lower functional connectivity (synchronization of brain activity among activated areas) than their age and ability comparison group in the left hemisphere language network during irony processing, and neither autism group had an increase in functional connectivity in response to increased task demands. Activation differences for the literal and irony conditions occurred in key language-processing regions (left middle temporal, left pars triangularis, left pars opercularis, left medial frontal, and right middle temporal). The children and adults with autism differed from each other in the use of some brain regions during the irony task, with the adults with autism having activation levels similar to those of the control groups. Overall, the children and adults with autism differed from the adult and child controls in (a) the degree of network coordination, (b) the distribution of the workload among member nodes, and (3) the dynamic recruitment of regions in response to text content. Moreover, the differences between the two autism age groups may be indicative of positive changes in the neural function related to language processing associated with maturation and/or educational experience.

  7. Regional brain shrinkage over two years: individual differences and effects of pro-inflammatory genetic polymorphisms. (United States)

    Persson, N; Ghisletta, P; Dahle, C L; Bender, A R; Yang, Y; Yuan, P; Daugherty, A M; Raz, N


    We examined regional changes in brain volume in healthy adults (N=167, age 19-79years at baseline; N=90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (Hc), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the Hc, CbH, In, OF, and PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants modified shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1β C-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFR C677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC, thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan.

  8. The neutral and affective verbal fluency in people with right, left or both hemisphere brain pathology [Fluencja słowna neutralna i afektywna u chorych z uszkodzeniem prawej, lewej lub obu półkul mózgu

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    Szepietowska, Ewa Małgorzata


    Full Text Available Aim. The comparison of neutral and affective fluency realisation in patients with right, left or both hemisphere brain damage and the control group, was the aim of our study. 31 healthy persona and 31 persons with vascular brain damage participated. (the left hemisphere (N = 11, right (N = 14 or both hemispheres (N = 6. Method. 4 fluency tasks were used: animals, “k” letter (the neutral tasks, pleasant and unpleasant (the affective tasks. The aim of our research was the assessment of the number of correct answers, number of mistakes, clusters as well as the switches between compliant and discordant with the type of the task. The level of depression as well as the level of linguistic abilities were considered in analyses. Results. The group of people with the CNS pathology generated less words and less clusters of both types (compliant and discordant with type of the task in comparison to healthy people. The character of CNS pathology did not differ the results, however we noted the tendencies to diverse realisation of affective fluency. In the neutral tasks persons generated more words than affective tasks independently of their clinical state, and they applied strategies compliant with the type of the task. Conclusions. The applying of the affective fluency can enrich the workshop of the clinical diagnosis. Tasks of this type engage other psychological and neuronal mechanisms than the traditional neutral fluency.

  9. Hemispheric Division of Labour in Reading (United States)

    Shillcock, Richard C.; McDonald, Scott A.


    We argue that the reading of words and text is fundamentally conditioned by the splitting of the fovea and the hemispheric division of the brain, and, furthermore, that the equitable division of labour between the hemispheres is a characteristic of normal visual word recognition. We report analyses of a representative corpus of the eye fixations…

  10. Differences in lateral hemispheric asymmetries of cerebral blood flow measured by SPECT in dementia of Alzheimer type

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, Nahoko (Niigata Univ. (Japan). School of Medicine)


    We studied 21 right-handed patients clinically diagnosed as dementia of Alzheimer type (8 men, 13 women; aged 53-85, mean 71.1 years). The average duration of symptoms was 2.7 years. Dementia ranged from mild to moderately severe. None had clinical or laboratory evidence of cerebro-vascular disease (Hachinski ischemic scores for all patients were 4 or below). All received the Wechsler Adult Intelligence Scale (WAIS), Mini-mental State Test (MMS) and Western Aphasia Battery (WAB, First Japanese edition, 1986). Regional cerebral blood flow was evaluated by single photon emission CT (SPECT) with [sup 123]I-N-isopropyl-p-iodoamphetamine ([sup 123]I-IMP), using the Matsuda's quantitative method. The subjects were divided into three groups on the basis of right-left hemispheric asymmetry of cerebral blood flow (lefthemispheric hypoperfusion (p<0.05). We concluded that cerebral blood flow asymmetry detected by SPECT was related significantly to the deficit of language and constructive function in patients with dementia of Alzheimer type. (author).

  11. Contralesional motor deficits after unilateral stroke reflect hemisphere-specific control mechanisms. (United States)

    Mani, Saandeep; Mutha, Pratik K; Przybyla, Andrzej; Haaland, Kathleen Y; Good, David C; Sainburg, Robert L


    We have proposed a model of motor lateralization, in which the left and right hemispheres are specialized for different aspects of motor control: the left hemisphere for predicting and accounting for limb dynamics and the right hemisphere for stabilizing limb position through impedance control mechanisms. Our previous studies, demonstrating different motor deficits in the ipsilesional arm of stroke patients with left or right hemisphere damage, provided a critical test of our model. However, motor deficits after stroke are most prominent on the contralesional side. Post-stroke rehabilitation has also, naturally, focused on improving contralesional arm impairment and function. Understanding whether contralesional motor deficits differ depending on the hemisphere of damage is, therefore, of vital importance for assessing the impact of brain damage on function and also for designing rehabilitation interventions specific to laterality of damage. We, therefore, asked whether motor deficits in the contralesional arm of unilateral stroke patients reflect hemisphere-dependent control mechanisms. Because our model of lateralization predicts that contralesional deficits will differ depending on the hemisphere of damage, this study also served as an essential assessment of our model. Stroke patients with mild to moderate hemiparesis in either the left or right arm because of contralateral stroke and healthy control subjects performed targeted multi-joint reaching movements in different directions. As predicted, our results indicated a double dissociation; although left hemisphere damage was associated with greater errors in trajectory curvature and movement direction, errors in movement extent were greatest after right hemisphere damage. Thus, our results provide the first demonstration of hemisphere specific motor control deficits in the contralesional arm of stroke patients. Our results also suggest that it is critical to consider the differential deficits induced by right

  12. Sex in the brain: hormones and sex differences. (United States)

    Marrocco, Jordan; McEwen, Bruce S


    Contrary to popular belief, sex hormones act throughout the entire brain of both males and females via both genomic and nongenomic receptors. Many neural and behavioral functions are affected by estrogens, including mood, cognitive function, blood pressure regulation, motor coordination, pain, and opioid sensitivity. Subtle sex differences exist for many of these functions that are developmentally programmed by hormones and by not yet precisely defined genetic factors, including the mitochondrial genome. These sex differences, and responses to sex hormones in brain regions and upon functions not previously regarded as subject to such differences, indicate that we are entering a new era in our ability to understand and appreciate the diversity of gender-related behaviors and brain functions.

  13. Is it a baby? Perceived age affects brain processing of faces differently in women and men. (United States)

    Proverbio, Alice Mado; Riva, Federica; Zani, Alberto; Martin, Eleonora


    It is known that infant faces stimulate visual and anterior brain regions belonging to the mesocortical limbic system (orbito-frontal cortex, anterior cingulate cortex, and nucleus accumbens) as well as the fusiform gyrus during face coding, suggesting a preferential response to baby schema. In the present investigation, faces of infants, children, and adults were presented to 40 male and female right-handed university students with technological objects (and inanimate scenarios to serve as targets) in a randomly mixed fashion. EEG was recorded from 128 scalp sites. In both sexes, the N1 response to infant faces was larger than the response to adult faces; however, the baby-specific N1 response was much larger in women than in men across the left hemisphere. The anterior N2 response to infants was greater than the response to children only in women, whereas the response to children of any age was larger than the response to adults in men. LORETA identified the intracranial sources of N2 response to infants in the left fusiform gyrus (FG), as well as the uncus, cingulate, and orbito-frontal cortices. The FG, the limbic, and especially the orbito-frontal sources were much larger in women than in men. The data suggest a sex difference in the brain response to faces of different ages and in the preferential response to infants, especially with regard to activation of the mesocorticolimbic system.

  14. Gender differences in brain serotonin transporter availability in panic disorder. (United States)

    Maron, Eduard; Tõru, Innar; Hirvonen, Jussi; Tuominen, Lauri; Lumme, Ville; Vasar, Veiko; Shlik, Jakov; Nutt, David J; Helin, Semi; Någren, Kjell; Tiihonen, Jari; Hietala, Jarmo


    The role of the serotonin (5-HT) system in the neurobiology and treatment of panic disorder (PD) remains unproven. Previously we detected lower brain 5-HT transporter (SERT) availability in PD, but the findings were preliminary and mainly limited to female patients. The aim of this study was to assess non-displaceable brain SERT binding potential (BP (ND)) in male and female patients with PD. The SERT BP (ND) was measured in groups of patients with PD (five males and six females) and matched healthy control subjects (12 males and 12 females) using positron emission tomography (PET) and [¹¹C]MADAM tracer. SERT BP (ND) were significantly higher in 13 of 20 studied brain regions, including several cortical and raphe areas, but lower in the hippocampus in males with PD as compared with healthy males. No significant differences in SERT BP (ND) were observed between female patients and controls. The results suggest gender-dependent regional differences in brain SERT availability and converge with previous PET findings of reduced 5-HT(1A) receptor binding in similar brain areas in PD. Distinctive functioning of the 5-HT system in males and females may underlie certain gender-dependent differences in expressions of PD.

  15. Different coexpressions of arthritis-relevant genes between different body organs and different brain regions in the normal mouse population. (United States)

    Cao, Yanhong; Huang, Yue; Wang, Lishi; Zhu, Jiaqian; Gu, Weikuan


    Structural changes in different parts of the brain in rheumatoid arthritis (RA) patients have been reported. RA is not regarded as a brain disease. Body organs such as spleen and lung produce RA-relevant genes. We hypothesized that the structural changes in the brain are caused by changes of gene expression in body organs. Changes in different parts of the brain may be affected by altered gene expressions in different body organs. This study explored whether an association between gene expressions of an organ or a body part varies in different brain structures. By examining the association of the 10 most altered genes from a mouse model of spontaneous arthritis in a normal mouse population, we found two groups of gene expression patterns between five brain structures and spleen. The correlation patterns between the prefrontal cortex, nucleus accumbens, and spleen were similar, while the associations between the other three parts of the brain and spleen showed a different pattern. Among overall patterns of the associations between body organs and brain structures, spleen and lung had a similar pattern, and patterns for kidney and liver were similar. Analysis of the five additional known arthritis-relevant genes produced similar results. Analysis of 10 nonrelevant-arthritis genes did not result in a strong association of gene expression or clearly segregated patterns. Our data suggest that abnormal gene expressions in different diseased body organs may influence structural changes in different brain parts.

  16. Unilateral hearing during development: hemispheric specificity in plastic reorganizations

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    Andrej eKral


    Full Text Available The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness. The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. The data revealed that effects of hearing experience were more pronounced when stimulating the hearing ear. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive

  17. A comparison of different models of stroke on behaviour and brain morphology. (United States)

    Gonzalez, C L R; Kolb, B


    We compared the effects of three models of permanent ischemia, as well as cortical aspiration, on behaviour and brain morphology. Rats received a stroke either by devascularization or by two different procedures of medial cerebral artery occlusion (MCAO; small vs. large). Animals were trained in a reaching task, forepaw asymmetry, forepaw inhibition, sunflower seed task and tongue extension. Behaviour was assessed 1 week after the lesion and at 2-week intervals for a total of 9 weeks. One week after the surgery all animals were severely impaired on all tasks and although they improved over time they only reached preoperative base lines on tongue extension. Animals with small MCAOs performed better in reaching and sunflower tasks; no other behavioural differences were detected among the groups. Pyramidal cells in forelimb and cingulate areas as well as spiny neurons of the striatum were examined for dendritic branching and spine density using a Golgi-Cox procedure. Each lesion type had a different impact on cell morphology. Overall, different changes (atrophy or hypertrophy) were observed with each kind of lesion and these changes were specific for the region (forelimb, cingulate, striatum) and the condition (intact vs. damaged hemisphere). These results suggest that: (i) different lesions to the motor cortex produce subtle differences in behaviour, and (ii) the method used to induce the lesion produces striking differences in cortical and subcortical plasticity.

  18. The Right Hemisphere in Aesthetic Perception

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    Bianca eBromberger


    Full Text Available Little about the neuropsychology of art perception and evaluation is known. Most neuropsychological approaches to art have focused on art production and have been anecdotal and qualitative. The field is in desperate need of quantitative methods if it is to advance. Here, we combine a quantitative approach to the assessment of art with modern voxel-lesion-symptom-mapping (VLSM methods to determine brain-behavior relationships in art perception. We hypothesized that perception of different attributes of art are likely to be disrupted by damage to different regions of the brain. Twenty participants with right hemisphere damage were given the Assessment of Art Attributes (AAA, which is designed to quantify judgments of descriptive attributes of visual art. Each participant rated 24 paintings on 6 conceptual attributes (depictive accuracy, abstractness, emotion, symbolism, realism, and animacy and 6 perceptual attributes (depth, color temperature, color saturation, balance, stroke, and simplicity and their interest in and preference for these paintings. Deviation scores were obtained for each brain-damaged participant for each attribute based on correlations with group average ratings from 30 age-matched healthy participants. Right hemisphere damage affected participants' judgments of abstractness, accuracy, and stroke quality. Damage to areas within different parts of the frontal parietal and lateral temporal cortices produced deviation in judgments in four of six conceptual attributes (abstractness, symbolism, realism and animacy. Of the formal attributes, only depth was affected by inferior prefrontal damage. No areas of brain damage were associated with deviations in interestingness or preference judgments. The perception of conceptual and formal attributes in artwork may in part dissociate from each other and from evaluative judgments. More generally, this approach demonstrates the feasibility of quantitative approaches to the neuropsychology of

  19. Dosha brain-types: A neural model of individual differences

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    Frederick T Travis


    Full Text Available This paper explores brain patterns associated with the three categories of regulatory principles of the body, mind, and behavior in Ayurveda, called Vata, Pitta, and Kapha dosha. A growing body of research has reported patterns of blood chemistry, genetic expression, physiological states, and chronic diseases associated with each dosha type. Since metabolic and growth factors are controlled by the nervous system, each dosha type should be associated with patterns of functioning of six major areas of the nervous system: The prefrontal cortex, the reticular activating system, the autonomic nervous system, the enteric nervous system, the limbic system, and the hypothalamus. For instance, the prefrontal cortex, which includes the anterior cingulate, ventral medial, and the dorsal lateral cortices, would exhibit a high range of functioning in the Vata brain-type leading to the possibility of being easily overstimulated. The Vata brain-type performs activity quickly. Learns quickly and forgets quickly. Their fast mind gives them an edge in creative problem solving. The Pitta brain-type reacts strongly to all challenges leading to purposeful and resolute actions. They never give up and are very dynamic and goal oriented. The Kapha brain-type is slow and steady leading to methodical thinking and action. They prefer routine and needs stimulation to get going. A model of dosha brain-types could provide a physiological foundation to understand individual differences. This model could help individualize treatment modalities to address different mental and physical dysfunctions. It also could explain differences in behavior seen in clinical as well as in normal populations.

  20. Brain metastases free survival differs between breast cancer subtypes (United States)

    Berghoff, A; Bago-Horvath, Z; De Vries, C; Dubsky, P; Pluschnig, U; Rudas, M; Rottenfusser, A; Knauer, M; Eiter, H; Fitzal, F; Dieckmann, K; Mader, R M; Gnant, M; Zielinski, C C; Steger, G G; Preusser, M; Bartsch, R


    Background: Brain metastases (BM) are frequently diagnosed in patients with HER-2-positive metastatic breast cancer; in addition, an increasing incidence was reported for triple-negative tumours. We aimed to compare brain metastases free survival (BMFS) of breast cancer subtypes in patients treated between 1996 until 2010. Methods: Brain metastases free survival was measured as the interval from diagnosis of extracranial breast cancer metastases until diagnosis of BM. HER-2 status was analysed by immunohistochemistry and reanalysed by fluorescent in situ hybridisation if a score of 2+ was gained. Oestrogen-receptor (ER) and progesterone-receptor (PgR) status was analysed by immunohistochemistry. Brain metastases free survival curves were estimated with the Kaplan–Meier method and compared with the log-rank test. Results: Data of 213 patients (46 luminal/124 HER-2/43 triple-negative subtype) with BM from breast cancer were available for the analysis. Brain metastases free survival differed significantly between breast cancer subtypes. Median BMFS in triple-negative tumours was 14 months (95% CI: 11.34–16.66) compared with 18 months (95% CI: 14.46–21.54) in HER-2-positive tumours (P=0.001) and 34 months (95% CI: 23.71–44.29) in luminal tumours (P=0.001), respectively. In HER-2-positive patients, co-positivity for ER and HER-2 prolonged BMFS (26 vs 15 m; P=0.033); in luminal tumours, co-expression of ER and PgR was not significantly associated with BMFS. Brain metastases free survival in patients with lung metastases was significantly shorter (17 vs 21 months; P=0.014). Conclusion: Brain metastases free survival in triple-negative breast cancer, as well as in HER-2-positive/ER-negative, is significantly shorter compared with HER-2/ER co-positive or luminal tumours, mirroring the aggressiveness of these breast cancer subtypes. PMID:22233926

  1. New Insights on Different Response of MDMA-Elicited Serotonin Syndrome to Systemic and Intracranial Administrations in the Rat Brain.

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    Ibrahim M Shokry

    Full Text Available In spite of the fact that systemic administration of MDMA elicits serotonin syndrome, direct intracranial administration fails to reproduce the effect. To reconcile these findings, it has been suggested that the cause of serotonin syndrome is attributed mainly to MDMA hepatic metabolites, and less likely to MDMA itself. Recently, however, this explanation has been challenged, and alternative hypotheses need to be explored. Here, we tested the hypothesis that serotonin syndrome is the result of excessive 5HT simultaneously in many brain areas, while MDMA administered intracranially fails to cause serotonin syndrome because it produces only a localized effect at the delivery site and not to other parts of the brain. This hypothesis was examined using adult male Sprague Dawley rats by comparing 5HT responses in the right and left hemispheric frontal cortices, right and left hemispheric diencephalons, and medullar raphe nucleus. Occurrence of serotonin syndrome was confirmed by measuring change in body temperature. Administration routes included intraperitoneal (IP, intracerebroventricular (ICV and reverse microdialysis. First, we found that IP administration caused excessive 5HT in all five sites investigated and induced hypothermia, suggesting the development of the serotonin syndrome. In contrast, ICV and reverse microdialysis caused excessive 5HT only in regions of delivery sites without changes in body-core temperature, suggesting the absence of the syndrome. Next, chemical dyes were used to trace differences in distribution and diffusion patterns between administration routes. After systemic administration, the dyes were found to be evenly distributed in the brain. However, the dyes administered through ICV or reverse microdialysis injection still remained in the delivery sites, poorly diffusing to the brain. In conclusion, intracranial MDMA administration in one area has no or little effect on other areas, which must be considered a plausible

  2. Hemisphere Susceptibility and Personality: a Replication Study (United States)

    Dimond, Stuart; Beaumont, Graham


    Author studied the capacity of the normal brain to carry out a paired-associate learning task by projecting the stimulus material to either the right or left hemisphere in order to establish if there was a lateral specialization for this type of learning in the normal brain. (Author/RK)

  3. Reading the Wrong Way with the Right Hemisphere

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    Ian J. Kirk


    Full Text Available Reading is a complex process, drawing on a variety of brain functions in order to link symbols to words and concepts. The three major brain areas linked to reading and phonological analysis include the left temporoparietal region, the left occipitotemporal region and the inferior frontal gyrus. Decreased activation of the left posterior language system in dyslexia is well documented but there is relatively limited attention given to the role of the right hemisphere. The current study investigated differences in right and left hemisphere activation between individuals with dyslexia and non-impaired readers in lexical decision tasks (regular words, irregular words, pseudowords during functional Magnetic Resonance Imaging (fMRI. Results revealed the expected hypo-activation in the left posterior areas in those with dyslexia but also areas of overactivation in the right hemisphere. During pseudoword decisions, for example, adults with dyslexia showed more right inferior occipital gyrus activation than controls. In general the increased activation of left-hemisphere language areas found in response to both regular and pseudowords was absent in dyslexics. Laterality indices showed that while controls showed left lateralised activation of the temporal lobe during lexical decision making, dyslexic readers showed right activation. Findings will inform theories of reading and will have implications for the design of reading interventions.

  4. A comparative autoradiography study in post mortem whole hemisphere human brain slices taken from Alzheimer patients and age-matched controls using two radiolabelled DAA1106 analogues with high affinity to the peripheral benzodiazepine receptor (PBR) system. (United States)

    Gulyás, Balázs; Makkai, Boglárka; Kása, Péter; Gulya, Károly; Bakota, Lidia; Várszegi, Szilvia; Beliczai, Zsuzsa; Andersson, Jan; Csiba, László; Thiele, Andrea; Dyrks, Thomas; Suhara, Tetsua; Suzuki, Kazutoshi; Higuchi, Makato; Halldin, Christer


    The binding of two radiolabelled analogues (N-(5-[125I]Iodo-2-phenoxyphenyl)-N-(2,5-dimethoxybenzyl)acetamide ([125I]desfluoro-DAA1106) and N-(5-[125I]Fluoro-2-phenoxyphenyl)-N-(2-[125I]Iodo-5-methoxybenzyl)acetamide ([125I]desmethoxy-DAA1106) of the peripheral benzodiazepine receptor (PBR) (or TSPO, 18kDa translocator protein) ligand DAA1106 was examined by in vitro autoradiography on human post mortem whole hemisphere brain slices obtained from Alzheimer's disease (AD) patients and age-matched controls. Both [(125)I]desfluoro-IDAA1106 and [(125)I]desmethoxy-IDAA1106 were effectively binding to various brain structures. The binding could be blocked by the unlabelled ligand as well as by other PBR specific ligands. With both radiolabelled compounds, the binding showed regional inhomogeneity and the specific binding values proved to be the highest in the hippocampus, temporal and parietal cortex, the basal ganglia and thalamus in the AD brains. Compared with age-matched control brains, specific binding in several brain structures (temporal and parietal lobes, thalamus and white matter) in Alzheimer brains was significantly higher, indicating that the radioligands can effectively label-activated microglia and the up-regulated PBR/TSPO system in AD. Complementary immunohistochemical studies demonstrated reactive microglia activation in the AD brain tissue and indicated that increased ligand binding coincides with increased regional microglia activation due to neuroinflammation. These investigations yield further support to the PBR/TSPO binding capacity of DAA1106 in human brain tissue, demonstrate the effective usefulness of its radio-iodinated analogues as imaging biomarkers in post mortem human studies, and indicate that its radiolabelled analogues, labelled with short half-time bioisotopes, can serve as prospective in vivo imaging biomarkers of activated microglia and the up-regulated PBR/TSPO system in the human brain.

  5. The Functional Organization of Trial-Related Activity in Lexical Processing after Early Left Hemispheric Brain Lesions: An Event-Related fMRI Study (United States)

    Fair, Damien A.; Choi, Alexander H.; Dosenbach, Yannic B. L.; Coalson, Rebecca S.; Miezin, Francis M.; Petersen, Steven E.; Schlaggar, Bradley L.


    Children with congenital left hemisphere damage due to perinatal stroke are capable of acquiring relatively normal language functions despite experiencing a cortical insult that in adults often leads to devastating lifetime disabilities. Although this observed phenomenon is accepted, its neurobiological mechanisms are not well characterized. In…

  6. General systems theory, brain organization, and early experiences. (United States)

    Denenberg, V H


    Three hypothetical brain processes--interhemispheric coupling, hemispheric activation, and interhemispheric inhibition--are derived from an equation characterizing general systems theory. To investigate these processes, experimental rats were reared under differing early experience conditions. When adult, they had their right or left neocortex lesioned, had a sham operation, or were left undisturbed. Interhemispheric coupling was measured by means of a correlation coefficient between the right and left hemispheres. The presence of a significant positive correlation is taken as evidence of a negative feedback loop between the hemispheres. In one experimental population, in which rats did not receive any extra stimulation in infancy, the correlation was not significantly different from zero, thus implying that the two hemispheres were operating independently. In another population, in which rats had received handling stimulation in infancy, the correlation coefficient was significant (0.543), indicating that the hemispheres were coupled in a systems arrangement. The processes of hemispheric activation and interhemispheric inhibition were assessed by comparing the mean performance of the two unilateral lesion groups and the group with intact brain. The two rat populations had different forms of brain organizations as measured by these processes. These analyses show that the behavior of the isolated hemisphere cannot be directly extrapolated to the behavior of the connected hemisphere. If there is hemispheric coupling via a negative feedback loop or if there is interhemispheric inhibition, then the disconnected hemisphere may show behaviors that are not evident in the normal connected condition.

  7. At the Frontier of Epigenetics of Brain Sex Differences

    Directory of Open Access Journals (Sweden)

    Margaret M Mccarthy


    Full Text Available The notion that epigenetics may play an important role in the establishment and maintenance of sex differences in the brain has garnered great enthusiasm but the reality in terms of actual advances have been slow. Two general approaches include the comparison of a particular epigenetic mark in males versus females and the inhibition of key epigenetic enzymes or co-factors to determine if this eliminates a particular sex difference in brain or behavior. The majority of emphasis has been on candidate genes such as steroid receptors. Only recently have more generalized survey type approaches been achieved and these promise to open new vista’s and accelerate discovery of important roles for DNA methylation, histone modification and microRNAs. Technical challenges abound and while not unique to this field will require novel thinking and new approaches by behavioral neuroendocrinogists.

  8. Different brains process numbers differently: structural bases of individual differences in spatial and nonspatial number representations. (United States)

    Krause, Florian; Lindemann, Oliver; Toni, Ivan; Bekkering, Harold


    A dominant hypothesis on how the brain processes numerical size proposes a spatial representation of numbers as positions on a "mental number line." An alternative hypothesis considers numbers as elements of a generalized representation of sensorimotor-related magnitude, which is not obligatorily spatial. Here we show that individuals' relative use of spatial and nonspatial representations has a cerebral counterpart in the structural organization of the posterior parietal cortex. Interindividual variability in the linkage between numbers and spatial responses (faster left responses to small numbers and right responses to large numbers; spatial-numerical association of response codes effect) correlated with variations in gray matter volume around the right precuneus. Conversely, differences in the disposition to link numbers to force production (faster soft responses to small numbers and hard responses to large numbers) were related to gray matter volume in the left angular gyrus. This finding suggests that numerical cognition relies on multiple mental representations of analogue magnitude using different neural implementations that are linked to individual traits.

  9. The effect of musical experience on hemispheric lateralization in musical feature processing. (United States)

    Ono, Kentaro; Nakamura, Akinori; Yoshiyama, Kenji; Kinkori, Takeshi; Bundo, Masahiko; Kato, Takashi; Ito, Kengo


    Music consists of a variety of spectral and temporal features. Generally, brain processing of these features is reported as being right hemisphere dominant. However, there are contradicting results as to whether musical experience affects hemispheric laterality or not. In the present study, we investigated the effect of musical experience on hemispheric lateralization of musical feature processing using magnetoencephalography (MEG). Mismatch fields (MMFs) were measured from 8 musicians and 8 nonmusicians in oddball tasks with four different musical features, including pitch, chord, timbre and rhythm. Regardless of the features, the MMFs showed right-hemispheric dominance in nonmusicians, whereas musicians showed symmetrical MMF amplitudes in both hemispheres. The electrical activity around the auditory cortex to the MMFs also supported the right-hemispheric dominance in nonmusicians and bilateral activation in musicians. Voxel-based morphometry did not detect any group differences around the auditory cortices. These results suggest that musical training changes the hemispheric roles for musical feature processing in the pre-attentive stage, and this functional alteration can occur without apparent anatomical changes.

  10. Peritumoral edema of meningiomas and metastatic brain tumors: differences in diffusion characteristics evaluated with diffusion-tensor MR imaging

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    Toh, Cheng-Hong; Wong, Alex M.-C; Wong, Ho-Fai; Wan, Yung-Liang [Chang Gung Memorial Hospital, Department of Medical Imaging and Intervention, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Wei, Kuo-Chen [Chang Gung Memorial Hospital, Department of Neurosurgery, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Ng, Shu-Hang [Chang Gung Memorial Hospital, Department of Medical Imaging and Intervention, Tao-Yuan (China); Chang Gung University, School of Medicine and Medical Technology, Tao-Yuan (China); Chang Gung Memorial Hospital, Molecular Image Center, Tao-Yuan (China)


    We prospectively compared the fractional anisotropy (FA) and mean diffusivity (MD) of the peritumoral edema of meningiomas and metastatic brain tumors with diffusion-tensor magnetic resonance (MR) imaging. The study protocol was approved by the local ethics committee, and written informed consent was obtained. Preoperative diffusion-tensor MR imaging was performed in 15 patients with meningiomas and 11 patients with metastatic brain tumors. Regions of interest (ROI) were placed in the peritumoral edema and normal-appearing white matter (NAWM) of the contralateral hemisphere to measure the FA and MD. The FA and MD ratios were calculated for each ROI in relation to the NAWM of the contralateral hemisphere. Changes in peritumoral MD and FA, in terms of primary values and ratios, were compared using a two-sample t-test; P < 0.05 was taken as indicating statistical significance. The mean MD values (x 10{sup -3} mm{sup 2}/s) of the peritumoral edema for metastases and meningiomas, respectively, were 0.902 {+-} 0.057 and 0.820 {+-} 0.094, the mean MD ratios were 220.3 {+-} 22.6 and 193.1 {+-} 23.4, the mean FA values were 0.146 {+-} 0.026 and 0.199 {+-} 0.052, and the mean FA ratios were 32.3 {+-} 5.9 and 46.0 {+-} 12.1. All the values were significantly different between metastases and meningiomas (MD values P = 0.016, MD ratios P = 0.006, FA values P = 0.005, FA ratios P = 0.002). The peritumoral edema of metastatic brain tumors and meningiomas show different MD and FA on diffusion-tensor MR imaging. (orig.)

  11. Structural connectivity asymmetry in the neonatal brain. (United States)

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


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

  12. Metabolic control of resting hemispheric cerebral blood flow is oxidative, not glycolytic


    Powers, William. J.; Videen, Tom O.; Markham, Joanne; Walter, Vonn; Perlmutter, Joel S.


    Although the close regional coupling of resting cerebral blood flow (CBF) with both cerebral metabolic rate of oxygen (CMRO2) and cerebral metabolic rate of glucose (CMRglc) within individuals is well documented, there are few data regarding the coupling between whole brain flow and metabolism among different subjects. To investigate the metabolic control of resting whole brain CBF, we performed multivariate analysis of hemispheric CMRO2, CMRglc, and other covariates as predictors of resting ...

  13. Cerebral specialization. [greater performance efficiency for certain mental abilities or processes by one cerebral hemisphere over another (United States)

    Morris, Robin D.; Hopkins, William D.; Rumbaugh, Duane M.


    The concept of greater performance efficiency for certain mental abilities or processes in one cerebral hemisphere rather than the other is referred to as 'cerebral lateralization'. The experimental paradigm for lateralization research involves the study of patients with one damaged hemisphere, which prevents their performance of a certain task or function; this approach, however, presents many difficulties in extrapolating to brain function in normal patients. Attention is presently given to gender differences in lateralization, cerebral asymmetries in other species, and the evolutionary bases of hemispheric specialization.

  14. Hemispheric specialization for linguistic processing of sung speech. (United States)

    Yelle, Serena K; Grimshaw, Gina M


    The two hemispheres of the brain play complementary roles in song perception, with the left hemisphere specialized for processing the linguistic aspects of song and the right hemisphere specialized for the processing of melody. However, very little is known about how language and melody interact. The present study tested the hypothesis that right hemisphere linguistic processing would be facilitated by the presence of melody. In a dichotic listening paradigm, participants (8 men, 43 women) performed a linguistic task while listening to spoken or sung speech. Contrary to the hypothesis, left hemisphere specialization for linguistic processing was identical whether the sentences were spoken or sung.

  15. Transcranial brain stimulation (TMS and tDCS for post-stroke aphasia rehabilitation: Controversies

    Directory of Open Access Journals (Sweden)

    Lucia Iracema Zanotto de Mendonça

    Full Text Available Transcranial brain stimulation (TS techniques have been investigated for use in the rehabilitation of post-stroke aphasia. According to previous reports, functional recovery by the left hemisphere improves recovery from aphasia, when compared with right hemisphere participation. TS has been applied to stimulate the activity of the left hemisphere or to inhibit homotopic areas in the right hemisphere. Various factors can interfere with the brain's response to TS, including the size and location of the lesion, the time elapsed since the causal event, and individual differences in the hemispheric language dominance pattern. The following questions are discussed in the present article: [a] Is inhibition of the right hemisphere truly beneficial?; [b] Is the transference of the language network to the left hemisphere truly desirable in all patients?; [c] Is the use of TS during the post-stroke subacute phase truly appropriate? Different patterns of neuroplasticity must occur in post-stroke aphasia.

  16. Is the brain of migraineurs "different" even in dreams? (United States)

    Lovati, C; DeAngeli, F; D'Amico, D; Giani, L; D'Alessandro, C M; Zardoni, M; Scaglione, V; Castoldi, D; Capiluppi, E; Curone, M; Bussone, G; Mariani, C


    Migraineurs brain is hyper-excitable and hypo-metabolic. Dreaming is a mental state characterized by hallucinatory features in which imagery, emotion, motor skills and memory are created de novo. To evaluate dreams in different kinds of headache. We included 219 controls; 148 migraineurs (66 with aura-MA, 82 without aura-MO); 45 tension type headache (TTH) patients. ICHD-II diagnostic criteria were used. Ad hoc questionnaire was used to evaluate oneiric activity. The Generalized Anxiety Disorder Questionnaire, and the Patient Health Questionnaire were administered to evaluate anxiety and mood. The prevalence of dreamers was similar in different groups. Frequency of visual and auditory dreams was not different between groups. Migraineurs, particularly MA, had an increased frequency of taste dreams (present in 19.6 % of controls, 40.9 % of MA, 23.2 % of MO, 11.1 % of TTH, p dreams (present in 20 % of controls, 36 % of MA, 35 % of MO and 20 % of TTH, p dreams among migraineurs seems to be specific, possibly reflecting a particular sensitivity of gustative and olfactory brain structures, as suggested by osmofobia and nausea, typical of migraine. This may suggest the role of some cerebral structures, such as amygdala and hypothalamus, which are known to be involved in migraine mechanisms as well in the biology of sleep and dreaming.

  17. Sex differences in the brain-an interplay of sex steroid hormones and sex chromosomes. (United States)

    Grgurevic, Neza; Majdic, Gregor


    Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies.

  18. Species differences in early patterning of the avian brain. (United States)

    McGowan, Luke; Kuo, Eric; Martin, Arnaud; Monuki, Edwin S; Striedter, Georg


    The telencephalon is proportionately larger in parrots than in galliformes (chicken-like birds), whereas the midbrain tectum is proportionately smaller. We here test the hypothesis that the adult species difference in midbrain proportion is due to an evolutionary change in early brain patterning. In particular, we compare the size of the early embryonic midbrain between parakeets (Melopsittacus undulatus) and bobwhite quail (Colinus virgianus) by examining the expression domains of transcription factors Pax6 and Gbx2, which are expressed in the forebrain and hindbrain, respectively. Because these expression domains form rostral and caudal borders with the presumptive midbrain when this region is specified (Hamburger-Hamilton stages 9-11), they allow us to measure and compare the sizes of a molecularly defined presumptive midbrain in the two species. Based on published data from older embryos, we predicted that the molecularly defined midbrain territory is significantly larger in quail than parakeets. Indeed, our data show that normalized midbrain length is 33% greater in quail and that the midbrain to forebrain ratio is 28% greater. This is strong evidence of a significant species difference in early brain patterning.

  19. Are soluble and membrane-bound rat brain acetylcholinesterase different

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    Andres, C.; el Mourabit, M.; Stutz, C.; Mark, J.; Waksman, A. (Centre de Neurochimie du C.N.R.S., Strasbourg, (France))


    Salt-soluble and detergent-soluble acetylcholinesterases (AChE) from adult rat brain were purified to homogeneity and studied with the aim to establish the differences existing between these two forms. It was found that the enzymatic activities of the purified salt-soluble AChE as well as the detergent-soluble AChE were dependent on the Triton X-100 concentration. Moreover, the interaction of salt-soluble AChE with liposomes suggests amphiphilic behaviour of this enzyme. Serum cholinesterase (ChE) did not bind to liposomes but its activity was also detergent-dependent. Detergent-soluble AChE remained in solution below critical micellar concentrations of Triton X-100. SDS polyacrylamide gel electrophoresis of purified, Biobeads-treated and iodinated detergent-soluble 11 S AChE showed, under non reducing conditions, bands of 69 kD, 130 kD and greater than 250 kD corresponding, respectively, to monomers, dimers and probably tetramers of the same polypeptide chain. Under reducing conditions, only a 69 kD band was detected. It is proposed that an amphiphilic environment stabilizes the salt-soluble forms of AChE in the brain in vivo and that detergent-soluble Biobeads-treated 11 S AChE possess hydrophobic domain(s) different from the 20 kD peptide already described.

  20. Age- and Brain Region-Specific Differences in Mitochondrial Bioenergetics in Brown Norway Rats (United States)

    U.S. Environmental Protection Agency — Differences in various mitochondrial bioenergetics parameters in different brain regions in different age groups. This dataset is associated with the following...

  1. Different climatic controls of soil δ13Corg in three mid-latitude regions of the Northern Hemisphere since the Last Glacial period

    Institute of Scientific and Technical Information of China (English)

    RAO ZhiGuo; ZHU ZhaoYu; ZHANG JiaWu


    Paleoecological records of soil δ13Corg from three regions in the middle latitudes of the Northern Hemisphere, including the Chinese Loess Plateau (CLP), the Great Plains and adjacent areas of North America and northwestern Europe, showed different variations since the Last Glacial period. An attempt was made to evaluate the causes for the difference in δ13Corg on the basis of the modern climatic data collected in these regions and of the modern C3 and C4 plant distributions. The analysis indicates that temperature, especially the growing season temperature, has a dominant control on the growth of C4 plants. When the mean annual or growing season temperatures are below the "threshold value", the growth of C4 plants is limited. When the temperature is above the "threshold value", C4 plants can grow under a wide range of precipitation. However, when the precipitation is high enough to favor the growth of trees, the proportions of C4 plants in local biomass will decline. The implicit control factor recovered by sedimentary records is consistent with the control factor on modern C3/C4 distribution. Pure C3 plants have been dominating the local biomass since the Last Glacial period in European loess region, mainly owing to the low local temperature. The increases in C4 plants from the late Pleistocene to the Holocene in the Chinese Loess Plateau, the Great Plains and adjacent areas, mainly reflect the influence of increasing temperature.

  2. Brain Size, IQ, and Racial-Group Differences: Evidence from Musculoskeletal Traits. (United States)

    Rushton, J. Philippe; Rushton, Elizabeth W.


    Correlated brain size differences with 37 musculoskeletal variables shown in evolutionary textbooks to change with brain size. Findings from a sample of more than 6,000 U.S. military personnel indicate that racial differences in brain size are securely established and are the most likely biological mediators of race differences in intelligence.…

  3. Brain size and visual environment predict species differences in paper wasp sensory processing brain regions (hymenoptera: vespidae, polistinae). (United States)

    O'Donnell, Sean; Clifford, Marie R; DeLeon, Sara; Papa, Christopher; Zahedi, Nazaneen; Bulova, Susan J


    The mosaic brain evolution hypothesis predicts that the relative volumes of functionally distinct brain regions will vary independently and correlate with species' ecology. Paper wasp species (Hymenoptera: Vespidae, Polistinae) differ in light exposure: they construct open versus enclosed nests and one genus (Apoica) is nocturnal. We asked whether light environments were related to species differences in the size of antennal and optic processing brain tissues. Paper wasp brains have anatomically distinct peripheral and central regions that process antennal and optic sensory inputs. We measured the volumes of 4 sensory processing brain regions in paper wasp species from 13 Neotropical genera including open and enclosed nesters, and diurnal and nocturnal species. Species differed in sensory region volumes, but there was no evidence for trade-offs among sensory modalities. All sensory region volumes correlated with brain size. However, peripheral optic processing investment increased with brain size at a higher rate than peripheral antennal processing investment. Our data suggest that mosaic and concerted (size-constrained) brain evolution are not exclusive alternatives. When brain regions increase with brain size at different rates, these distinct allometries can allow for differential investment among sensory modalities. As predicted by mosaic evolution, species ecology was associated with some aspects of brain region investment. Nest architecture variation was not associated with brain investment differences, but the nocturnal genus Apoica had the largest antennal:optic volume ratio in its peripheral sensory lobes. Investment in central processing tissues was not related to nocturnality, a pattern also noted in mammals. The plasticity of neural connections in central regions may accommodate evolutionary shifts in input from the periphery with relatively minor changes in volume.

  4. Brain differences between persistent and remitted attention deficit hyperactivity disorder. (United States)

    Mattfeld, Aaron T; Gabrieli, John D E; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Kotte, Amelia; Kagan, Elana; Whitfield-Gabrieli, Susan


    Previous resting state studies examining the brain basis of attention deficit hyperactivity disorder have not distinguished between patients who persist versus those who remit from the diagnosis as adults. To characterize the neurobiological differences and similarities of persistence and remittance, we performed resting state functional magnetic resonance imaging in individuals who had been longitudinally and uniformly characterized as having or not having attention deficit hyperactivity disorder in childhood and again in adulthood (16 years after baseline assessment). Intrinsic functional brain organization was measured in patients who had a persistent diagnosis in childhood and adulthood (n = 13), in patients who met diagnosis in childhood but not in adulthood (n = 22), and in control participants who never had attention deficit hyperactivity disorder (n = 17). A positive functional correlation between posterior cingulate and medial prefrontal cortices, major components of the default-mode network, was reduced only in patients whose diagnosis persisted into adulthood. A negative functional correlation between medial and dorsolateral prefrontal cortices was reduced in both persistent and remitted patients. The neurobiological dissociation between the persistence and remittance of attention deficit hyperactivity disorder may provide a framework for the relation between the clinical diagnosis, which indicates the need for treatment, and additional deficits that are common, such as executive dysfunctions.

  5. Individual Differences in Hemispheric Specialization (United States)


    divided according to psychopathy ratings (high, medium, low) failed to differentiate among the groups thus tested. Sandel young aggressive boys. Journal of Educational Psychology, 69, 129-135. Hare, R.D., and McPherson, M. (1984). Psychopathy and perceptual...asymetry during verbal dlchotic listening. Journal of Abnormal Psychology, 93, Hare, R.C. (1979). Psychopathy and laterality of cerebral function

  6. Neuropsychological and brain volume differences in patients with left- and right-beginning corticobasal syndrome.

    Directory of Open Access Journals (Sweden)

    Kerstin Jütten

    Full Text Available BACKGROUND: Corticobasal Syndrome (CBS is a rare neurodegenerative syndrome characterized by unilaterally beginning frontoparietal and basal ganglia atrophy. The study aimed to prove the hypothesis that there are differences in hemispheric susceptibility to disease-related changes. METHODS: Two groups of CBS patients with symptoms starting either on the left or right body side were investigated. Groups consisted of four patients each and were matched for sex, age and disease duration. Patient groups and a group of eight healthy age-matched controls were analyzed using deformation field morphometry and neuropsychological testing. To further characterize individual disease progression regarding brain atrophy and neuropsychological performance, two female, disease duration-matched patients differing in initially impaired body side were followed over six months. RESULTS: A distinct pattern of neural atrophy and neuropsychological performance was revealed for both CBS: Patients with initial right-sided impairment (r-CBS revealed atrophy predominantly in frontoparietal areas and showed, except from apraxia, no other cognitive deficits. In contrast, patients with impairment of the left body side (l-CBS revealed more widespread atrophy, extending from frontoparietal to orbitofrontal and temporal regions; and apraxia, perceptional and memory deficits could be found. A similar pattern of morphological and neuropsychological differences was found for the individual disease progression in l-CBS and r-CBS single cases. CONCLUSIONS: For similar durations of disease, volumetric grey matter loss related to CBS pathology appeared earlier and progressed faster in l-CBS than in r-CBS. Cognitive impairment in r-CBS was characterized by apraxia, and additional memory and perceptional deficits for l-CBS.

  7. Comparing Different Classifiers in Sensory Motor Brain Computer Interfaces.

    Directory of Open Access Journals (Sweden)

    Hossein Bashashati

    Full Text Available A problem that impedes the progress in Brain-Computer Interface (BCI research is the difficulty in reproducing the results of different papers. Comparing different algorithms at present is very difficult. Some improvements have been made by the use of standard datasets to evaluate different algorithms. However, the lack of a comparison framework still exists. In this paper, we construct a new general comparison framework to compare different algorithms on several standard datasets. All these datasets correspond to sensory motor BCIs, and are obtained from 21 subjects during their operation of synchronous BCIs and 8 subjects using self-paced BCIs. Other researchers can use our framework to compare their own algorithms on their own datasets. We have compared the performance of different popular classification algorithms over these 29 subjects and performed statistical tests to validate our results. Our findings suggest that, for a given subject, the choice of the classifier for a BCI system depends on the feature extraction method used in that BCI system. This is in contrary to most of publications in the field that have used Linear Discriminant Analysis (LDA as the classifier of choice for BCI systems.

  8. Comparing Different Classifiers in Sensory Motor Brain Computer Interfaces. (United States)

    Bashashati, Hossein; Ward, Rabab K; Birch, Gary E; Bashashati, Ali


    A problem that impedes the progress in Brain-Computer Interface (BCI) research is the difficulty in reproducing the results of different papers. Comparing different algorithms at present is very difficult. Some improvements have been made by the use of standard datasets to evaluate different algorithms. However, the lack of a comparison framework still exists. In this paper, we construct a new general comparison framework to compare different algorithms on several standard datasets. All these datasets correspond to sensory motor BCIs, and are obtained from 21 subjects during their operation of synchronous BCIs and 8 subjects using self-paced BCIs. Other researchers can use our framework to compare their own algorithms on their own datasets. We have compared the performance of different popular classification algorithms over these 29 subjects and performed statistical tests to validate our results. Our findings suggest that, for a given subject, the choice of the classifier for a BCI system depends on the feature extraction method used in that BCI system. This is in contrary to most of publications in the field that have used Linear Discriminant Analysis (LDA) as the classifier of choice for BCI systems.

  9. Sex Differences in Serotonin 1 Receptor Binding in Rat Brain (United States)

    Fischette, Christine T.; Biegon, Anat; McEwen, Bruce S.


    Male and female rats exhibit sex differences in binding by serotonin 1 receptors in discrete areas of the brain, some of which have been implicated in the control of ovulation and of gonadotropin release. The sex-specific changes in binding, which occur in response to the same hormonal (estrogenic) stimulus, are due to changes in the number of binding sites. Castration alone also affects the number of binding sites in certain areas. The results lead to the conclusion that peripheral hormones modulate binding by serotonin 1 receptors. The status of the serotonin receptor system may affect the reproductive capacity of an organism and may be related to sex-linked emotional disturbances in humans.

  10. Rethinking a Right Hemisphere Deficit in ADHD (United States)

    Hale, T. Sigi; Loo, Sandra K.; Zaidel, Eran; Hanada, Grant; Macion, James; Smalley, Susan L.


    Introduction: Early observations from lesion studies suggested right hemisphere (RH) dysfunction in ADHD. However, a strictly right-lateralized deficit has not been well supported. An alternatively view suggests increased R greater than L asymmetry of brain function and abnormal interhemispheric interaction. If true, RH pathology in ADHD should…

  11. Alteration of Interictal Brain Activity in Patients with Temporal Lobe Epilepsy in the Left Dominant Hemisphere: A Resting-State MEG Study

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    Haitao Zhu


    Full Text Available Resting MEG activities were compared between patients with left temporal lobe epilepsy (LTLE and normal controls. Using SAMg2, the activities of MEG data were reconstructed and normalized. Significantly elevated SAMg2 signals were found in LTLE patients in the left temporal lobe and medial structures. Marked decreases of SAMg2 signals were found in the wide extratemporal lobe regions, such as the bilateral visual cortex. The study also demonstrated a positive correlation between the seizure frequency and brain activities of the abnormal regions after the multiple linear regression analysis. These results suggested that the aberrant brain activities not only were related to the epileptogenic zones, but also existed in other extratemporal regions in patients with LTLE. The activities of the aberrant regions could be further damaged with the increase of the seizure frequency. Our findings indicated that LTLE could be a multifocal disease, including complex epileptic networks and brain dysfunction networks.

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

    NARCIS (Netherlands)

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


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

  13. Brain Injury Differences in Frontal Impact Crash Using Different Simulation Strategies

    Directory of Open Access Journals (Sweden)

    Dao Li


    Full Text Available In the real world crashes, brain injury is one of the leading causes of deaths. Using isolated human head finite element (FE model to study the brain injury patterns and metrics has been a simplified methodology widely adopted, since it costs significantly lower computation resources than a whole human body model does. However, the degree of precision of this simplification remains questionable. This study compared these two kinds of methods: (1 using a whole human body model carried on the sled model and (2 using an isolated head model with prescribed head motions, to study the brain injury. The distribution of the von Mises stress (VMS, maximum principal strain (MPS, and cumulative strain damage measure (CSDM was used to compare the two methods. The results showed that the VMS of brain mainly concentrated at the lower cerebrum and occipitotemporal region close to the cerebellum. The isolated head modelling strategy predicted higher levels of MPS and CSDM 5%, while the difference is small in CSDM 10% comparison. It suggests that isolated head model may not equivalently reflect the strain levels below the 10% compared to the whole human body model.

  14. Hemispheric specialisation in haptic processing. (United States)

    Tomlinson, Simon P; Davis, Nick J; Morgan, Helen M; Bracewell, R Martyn


    This study investigated the organising principles of touch. We examined specialisations within the haptic system and their hemispheric distribution. Haptic processing consists of the integration of data from multiple sources to form a single percept. Previous research provides strong support for a hierarchical and functional distribution within haptic processing. We investigated hemispheric asymmetry in haptic discrimination of objects with differing textures and centres of mass. By analogy with vision it was hypothesised that participants would demonstrate a left-hand advantage for centre of mass discrimination (a 'global', presumed right hemisphere, judgement) and a right-hand advantage for surface texture judgements (a 'local', presumed left hemisphere discrimination). We found that left-handed participants showed these effects to a lesser degree than did the right-handers, consistent with the notion that left-handed people generally show weaker asymmetries in bimanual tasks. In a second experiment the effect of conflicting information on haptic percept formation was investigated. Following from the previous hypotheses it was predicted that participants would be more accurate with their right hands at judging conflicting surfaces. Contrary to predictions an advantage was demonstrated for the left hand for texture discrimination and for the right hand for centre of mass judgement.

  15. Brain switches utilitarian behavior: does gender make the difference?

    Directory of Open Access Journals (Sweden)

    Manuela Fumagalli

    Full Text Available Decision often implies a utilitarian choice based on personal gain, even at the expense of damaging others. Despite the social implications of utilitarian behavior, its neurophysiological bases remain largely unknown. To assess how the human brain controls utilitarian behavior, we delivered transcranial direct current stimulation (tDCS over the ventral prefrontal cortex (VPC and over the occipital cortex (OC in 78 healthy subjects. Utilitarian judgment was assessed with the moral judgment task before and after tDCS. At baseline, females provided fewer utilitarian answers than males for personal moral dilemmas (p = .007. In males, VPC-tDCS failed to induce changes and in both genders OC-tDCS left utilitarian judgments unchanged. In females, cathodal VPC-tDCS tended to decrease whereas anodal VPC-tDCS significantly increased utilitarian responses (p = .005. In males and females, reaction times for utilitarian responses significantly decreased after cathodal (p<.001 but not after anodal (p = .735 VPC-tDCS. We conclude that ventral prefrontal tDCS interferes with utilitarian decisions, influencing the evaluation of the advantages and disadvantages of each option in both sexes, but does so more strongly in females. Whereas cathodal tDCS alters the time for utilitarian reasoning in both sexes, anodal stimulation interferes more incisively in women, modifying utilitarian reasoning and the possible consequent actions. The gender-related tDCS-induced changes suggest that the VPC differentially controls utilitarian reasoning in females and in males. The gender-specific functional organization of the brain areas involved in utilitarian behavior could be a correlate of the moral and social behavioral differences between the two sexes.

  16. Brain Switches Utilitarian Behavior: Does Gender Make the Difference? (United States)

    Fumagalli, Manuela; Vergari, Maurizio; Pasqualetti, Patrizio; Marceglia, Sara; Mameli, Francesca; Ferrucci, Roberta; Mrakic-Sposta, Simona; Zago, Stefano; Sartori, Giuseppe; Pravettoni, Gabriella; Barbieri, Sergio; Cappa, Stefano; Priori, Alberto


    Decision often implies a utilitarian choice based on personal gain, even at the expense of damaging others. Despite the social implications of utilitarian behavior, its neurophysiological bases remain largely unknown. To assess how the human brain controls utilitarian behavior, we delivered transcranial direct current stimulation (tDCS) over the ventral prefrontal cortex (VPC) and over the occipital cortex (OC) in 78 healthy subjects. Utilitarian judgment was assessed with the moral judgment task before and after tDCS. At baseline, females provided fewer utilitarian answers than males for personal moral dilemmas (p = .007). In males, VPC-tDCS failed to induce changes and in both genders OC-tDCS left utilitarian judgments unchanged. In females, cathodal VPC-tDCS tended to decrease whereas anodal VPC-tDCS significantly increased utilitarian responses (p = .005). In males and females, reaction times for utilitarian responses significantly decreased after cathodal (p<.001) but not after anodal (p = .735) VPC-tDCS. We conclude that ventral prefrontal tDCS interferes with utilitarian decisions, influencing the evaluation of the advantages and disadvantages of each option in both sexes, but does so more strongly in females. Whereas cathodal tDCS alters the time for utilitarian reasoning in both sexes, anodal stimulation interferes more incisively in women, modifying utilitarian reasoning and the possible consequent actions. The gender-related tDCS-induced changes suggest that the VPC differentially controls utilitarian reasoning in females and in males. The gender-specific functional organization of the brain areas involved in utilitarian behavior could be a correlate of the moral and social behavioral differences between the two sexes. PMID:20111608

  17. 论汉字认知在促进儿童大脑两半球均衡发展中的作用%Role of Chinese characters cognition in promoting balanced development of both brain hemispheres in children

    Institute of Scientific and Technical Information of China (English)



    凝聚了汉民族高度智慧的汉字是一种“复脑文字”,它不仅内涵了丰富的民族文化基因,而且以其既能以形达意、又能以形表音的双向多重联想的表意性功能和极具视觉意象性的方块形特征,显示出在促进儿童大脑左右两半球均衡发展中的重要价值。%Chinese characters, which condense the wisdom of Chinese people, are a kind of “complex brain words” . Chinese characters bear the abundant connotations of national culture gene, possess the bi-directional associations between ideography and highly visualized squared shape, and play an important role in promoting the balanced develop-ment of both brain hemispheres in children.

  18. Brain Responses Differ to Faces of Mothers and Fathers (United States)

    Arsalidou, Marie; Barbeau, Emmanuel J.; Bayless, Sarah J.; Taylor, Margot J.


    We encounter many faces each day but relatively few are personally familiar. Once faces are familiar, they evoke semantic and social information known about the person. Neuroimaging studies demonstrate differential brain activity to familiar and non-familiar faces; however, brain responses related to personally familiar faces have been more rarely…

  19. Self-Organizing Individual Differences in Brain Development (United States)

    Lewis, Marc D.


    Brain development is self-organizing in that the unique structure of each brain evolves in unpredictable ways through recursive modifications of synaptic networks. In this article, I review mechanisms of neural change in real time and over development, and I argue that change at each of these time scales embodies principles of self-organizing…

  20. PTSD May Affect Boys, Girls Differently, Brain Scans Show (United States)

    ... area of the brain involved in emotion and empathy. This brain area was larger in boys with ... MedlinePlus Connect for EHRs For Developers U.S. National Library of ... and Human Services National Institutes of Health Page last updated on ...

  1. Southern hemisphere observations (United States)

    Orchiston, Wayne

    Because of insurmountable problems associated with absolute dating, the non-literate cultures of the Southern Hemisphere can contribute little to Applied Historical Astronomy, although Maori traditions document a possible supernova dating to the period 1000-1770 AD. In contrast, the abundant nineteenth century solar, planetary, cometary and stellar observational data provided by Southern Hemisphere professional and amateur observatories can serve as an invaluable mine of information for present-day astronomers seeking to incorporate historical data in their investigations.

  2. Hemispherical Laue camera (United States)

    Li, James C. M.; Chu, Sungnee G.


    A hemispherical Laue camera comprises a crystal sample mount for positioning a sample to be analyzed at the center of sphere of a hemispherical, X-radiation sensitive film cassette, a collimator, a stationary or rotating sample mount and a set of standard spherical projection spheres. X-radiation generated from an external source is directed through the collimator to impinge onto the single crystal sample on the stationary mount. The diffracted beam is recorded on the hemispherical X-radiation sensitive film mounted inside the hemispherical film cassette in either transmission or back-reflection geometry. The distances travelled by X-radiation diffracted from the crystal to the hemispherical film are the same for all crystal planes which satisfy Bragg's Law. The recorded diffraction spots or Laue spots on the film thereby preserve both the symmetry information of the crystal structure and the relative intensities which are directly related to the relative structure factors of the crystal orientations. The diffraction pattern on the exposed film is compared with the known diffraction pattern on one of the standard spherical projection spheres for a specific crystal structure to determine the orientation of the crystal sample. By replacing the stationary sample support with a rotating sample mount, the hemispherical Laue camera can be used for crystal structure determination in a manner previously provided in conventional Debye-Scherrer cameras.

  3. Concept and verbal ability as related to the cerebral hemispheres. (United States)

    Cook, N D


    A new theory of human brain function is outlined in terms of the cooperative interaction of the cerebral hemispheres. The well-established verbal, symbolic functions of the left hemisphere and the wholistic, spatial functions of the right hemisphere are seen as separate and independent manifestations of the normally integrated verbal-analytic (or "error detector") and conceptual (or "goal state") functions of the left and right, respectively. The relationship between the hemispheres is described in terms of the "goal-directed" system of cybernetics and then compared with related ideas previously presented by Dimond, Penfield, and Piaget.

  4. Hemispheric Asymmetries in the Activation and Monitoring of Memory Errors (United States)

    Giammattei, Jeannette; Arndt, Jason


    Previous research on the lateralization of memory errors suggests that the right hemisphere's tendency to produce more memory errors than the left hemisphere reflects hemispheric differences in semantic activation. However, all prior research that has examined the lateralization of memory errors has used self-paced recognition judgments. Because…

  5. Control of reach extent with the paretic and nonparetic arms after unilateral sensorimotor stroke: kinematic differences based on side of brain damage. (United States)

    Stewart, Jill Campbell; Gordon, James; Winstein, Carolee J


    Scaling of reach kinematics to targets that vary in distance is indicative of the use of planning and feedback-based adjustments. The control of reach extent, however, has not been reported for the paretic arm after stroke. The purpose of this study was to determine whether individuals post-stroke utilized planning (scaling acceleration magnitude) and feedback-based adjustments (scaling acceleration duration) to reach to targets that varied in distance. Individuals with mild-to-moderate motor impairment after stroke and nondisabled adults reached with both arms to targets presented at three distances (8, 16, 24 cm). Kinematic data were used to determine scaling of peak acceleration magnitude and duration to target distance and compared between arms (control, nonparetic, paretic). Despite differences in the magnitude of movement variables, individuals post-stroke utilized both planning and feedback-based adjustments to meet the demands of the task with the nonparetic and paretic arms in a similar manner as controls. However, there was variability in the use of planning with the paretic arm, some individuals utilized planning while others did not. After right brain damage, differences in reach control related to the specialized role this hemisphere plays in endpoint control were found in both arms; no hemisphere-specific changes were found after left brain damage (LBD). The appearance of hemispheric-specific effects after right but not LBD were not due to age, degree of motor impairment, or time post-stroke, but, instead, may be related to relative differences in visual-motor processing ability, lesion characteristics, or interhemispheric inhibition changes between groups.

  6. Is neuroinflammation in the injured spinal cord different than in the brain? Examining intrinsic differences between the brain and spinal cord. (United States)

    Zhang, B; Gensel, J C


    The field of neuroimmunology is rapidly advancing. There is a growing appreciation for heterogeneity, both in inflammatory composition and region-specific inflammatory responses. This understanding underscores the importance of developing targeted immunomodulatory therapies for treating neurological disorders. Concerning neurotrauma, there is a dearth of publications directly comparing inflammatory responses in the brain and spinal cord after injury. The question therefore remains as to whether inflammatory cells responding to spinal cord vs. brain injury adopt similar functions and are therefore amenable to common therapies. In this review, we address this question while revisiting and modernizing the conclusions from publications that have directly compared inflammation across brain and spinal cord injuries. By examining molecular differences, anatomical variations, and inflammatory cell phenotypes between the injured brain and spinal cord, we provide insight into how neuroinflammation relates to neurotrauma and into fundamental differences between the brain and spinal cord.

  7. Brain Signal Analysis Using Different Types of Music

    Directory of Open Access Journals (Sweden)

    Siti Ayuni Mohd Nasir


    Full Text Available Music is able to improve certain functions of human body physiologically and psychologically. Music also can improve attention, memory, and even mental math ability by listening to the music before performing any task. The purpose of this study is to study the relation between types of music and brainwaves signal that is differences in state of relaxation and attention states. The Electroencephalography (EEG signal was recorded using PowerLab, Dual Bio Amp and computer to observes and records the subject brain activity in three condition; before, during, and after listening to different types of music; Light, Rock, Mozart, Al-Quran recitation and Jazz. The brainwave reaction of the subjects is compared during these three conditions. The hypothesis of this study is; Beta wave is increased at attention state and decrease at relaxation state. To analyze the data, Labchart7 software was used. The EEG data that has been recorded is processed using Digital Filter and the features of EEG signal is extracted and recorded by Data Pad that included in Labchart7 software. Then, the data is analyzed from mean of group features and also the average amplitude of Alpha and Beta wave. The results from this study are; the attention state of students is increased (Beta increased while listening to Rock, AlQuran recitation and Mozart music when compared between during and before condition. Meanwhile, Beta wave is decreased while listening to Light and Jazz music thus showing the decrements of student’s state attention. Therefore, the result obtained may help students to choose better type of music or similar to help increases their concentration and focus while study.

  8. Associations between Family Adversity and Brain Volume in Adolescence: Manual vs. Automated Brain Segmentation Yields Different Results (United States)

    Lyden, Hannah; Gimbel, Sarah I.; Del Piero, Larissa; Tsai, A. Bryna; Sachs, Matthew E.; Kaplan, Jonas T.; Margolin, Gayla; Saxbe, Darby


    Associations between brain structure and early adversity have been inconsistent in the literature. These inconsistencies may be partially due to methodological differences. Different methods of brain segmentation may produce different results, obscuring the relationship between early adversity and brain volume. Moreover, adolescence is a time of significant brain growth and certain brain areas have distinct rates of development, which may compromise the accuracy of automated segmentation approaches. In the current study, 23 adolescents participated in two waves of a longitudinal study. Family aggression was measured when the youths were 12 years old, and structural scans were acquired an average of 4 years later. Bilateral amygdalae and hippocampi were segmented using three different methods (manual tracing, FSL, and NeuroQuant). The segmentation estimates were compared, and linear regressions were run to assess the relationship between early family aggression exposure and all three volume segmentation estimates. Manual tracing results showed a positive relationship between family aggression and right amygdala volume, whereas FSL segmentation showed negative relationships between family aggression and both the left and right hippocampi. However, results indicate poor overlap between methods, and different associations were found between early family aggression exposure and brain volume depending on the segmentation method used. PMID:27656121

  9. Northern Hemisphere forcing of Southern Hemisphere climate during the last deglaciation. (United States)

    He, Feng; Shakun, Jeremy D; Clark, Peter U; Carlson, Anders E; Liu, Zhengyu; Otto-Bliesner, Bette L; Kutzbach, John E


    According to the Milankovitch theory, changes in summer insolation in the high-latitude Northern Hemisphere caused glacial cycles through their impact on ice-sheet mass balance. Statistical analyses of long climate records supported this theory, but they also posed a substantial challenge by showing that changes in Southern Hemisphere climate were in phase with or led those in the north. Although an orbitally forced Northern Hemisphere signal may have been transmitted to the Southern Hemisphere, insolation forcing can also directly influence local Southern Hemisphere climate, potentially intensified by sea-ice feedback, suggesting that the hemispheres may have responded independently to different aspects of orbital forcing. Signal processing of climate records cannot distinguish between these conditions, however, because the proposed insolation forcings share essentially identical variability. Here we use transient simulations with a coupled atmosphere-ocean general circulation model to identify the impacts of forcing from changes in orbits, atmospheric CO(2) concentration, ice sheets and the Atlantic meridional overturning circulation (AMOC) on hemispheric temperatures during the first half of the last deglaciation (22-14.3 kyr BP). Although based on a single model, our transient simulation with only orbital changes supports the Milankovitch theory in showing that the last deglaciation was initiated by rising insolation during spring and summer in the mid-latitude to high-latitude Northern Hemisphere and by terrestrial snow-albedo feedback. The simulation with all forcings best reproduces the timing and magnitude of surface temperature evolution in the Southern Hemisphere in deglacial proxy records. AMOC changes associated with an orbitally induced retreat of Northern Hemisphere ice sheets is the most plausible explanation for the early Southern Hemisphere deglacial warming and its lead over Northern Hemisphere temperature; the ensuing rise in atmospheric CO(2

  10. Asymmetric auroral intensities in the Earth's Northern and Southern hemispheres (United States)

    Laundal, K. M.; Østgaard, N.


    It is commonly assumed that the aurora borealis (Northern Hemisphere) and aurora australis (Southern Hemisphere) are mirror images of each other because the charged particles causing the aurora follow the magnetic field lines connecting the two hemispheres. The particles are believed to be evenly distributed between the two hemispheres, from the source region in the equatorial plane of the magnetosphere. Although it has been shown that similar auroral features in the opposite hemispheres can be displaced tens of degree in longitude and that seasonal effects can cause differences in global intensity, the overall auroral patterns were still similar. Here we report observations that clearly contradict the common assumption about symmetric aurora: intense spots are seen at dawn in the Northern summer Hemisphere, and at dusk in the Southern winter Hemisphere. The asymmetry is interpreted in terms of inter-hemispheric currents related to seasons, which have been predicted but hitherto had not been seen.

  11. Divergent hemispheric reasoning strategies: reducing uncertainty versus resolving inconsistency (United States)

    Marinsek, Nicole; Turner, Benjamin O.; Gazzaniga, Michael; Miller, Michael B.


    Converging lines of evidence from diverse research domains suggest that the left and right hemispheres play distinct, yet complementary, roles in inferential reasoning. Here, we review research on split-brain patients, brain-damaged patients, delusional patients, and healthy individuals that suggests that the left hemisphere tends to create explanations, make inferences, and bridge gaps in information, while the right hemisphere tends to detect conflict, update beliefs, support mental set-shifts, and monitor and inhibit behavior. Based on this evidence, we propose that the left hemisphere specializes in creating hypotheses and representing causality, while the right hemisphere specializes in evaluating hypotheses, and rejecting those that are implausible or inconsistent with other evidence. In sum, we suggest that, in the domain of inferential reasoning, the left hemisphere strives to reduce uncertainty while the right hemisphere strives to resolve inconsistency. The hemispheres’ divergent inferential reasoning strategies may contribute to flexible, complex reasoning in the healthy brain, and disruption in these systems may explain reasoning deficits in the unhealthy brain. PMID:25374526

  12. Hyperlalia: A Right Cerebral Hemisphere Syndrome

    Directory of Open Access Journals (Sweden)

    Atsushi Yamadori


    Full Text Available We describe a new right hemispheric behavioural syndrome for which we propose the name “hyperlalia”. In a typical case an apparently unconcerned and expressionless patient is easily prompted to remarkable volubility with a content which is loose and incoherent. The voice is low and monotonous. All the lesions confirmed by computed tomography of the brain overlapped in the perisylvian area in the territory of the right middle cerebral artery. Loss of a subtle balance between the left hemispheric speech area and the corresponding area in the right hemisphere caused by acute damage of the right perisylvian area may have resulted in disinhibition of the speech function. Similarities and dissimilarities with the known pathology of talkativeness are also discussed.

  13. Hemispheric ultra-wideband antenna.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley


    This report begins with a review of reduced size ultra-wideband (UWB) antennas and the peculiar problems that arise when building a UWB antenna. It then gives a description of a new type of UWB antenna that resolves these problems. This antenna, dubbed the hemispheric conical antenna, is similar to a conventional conical antenna in that it uses the same inverted conical conductor over a ground plane, but it also uses a hemispheric dielectric fill in between the conductive cone and the ground plane. The dielectric material creates a fundamentally new antenna which is reduced in size and much more rugged than a standard UWB conical antenna. The creation of finite-difference time domain (FDTD) software tools in spherical coordinates, as described in SAND2004-6577, enabled this technological advance.

  14. Psychological differences between influence of temperament with the hemishere asymmetry of a brain on size of sensorymotor reactions of male and female cosmonauts (United States)

    Prisniakova, Lyudmila; Prisniakov, Volodymyr; Volkov, D. S.

    The purpose of research was definition and comparison of relative parameters of sensorimotor reactions with a choice depending on a level of lateral asymmetry of hemispheres of a brain at representatives of various types of temperament OF male and female cosmonauts . These parameters were by the bases for verification of theoretical dependence for the latent period of reaction in conditions of weightlessness and overloads. The hypothesis about influence of functional asymmetry on parameters of psychomotor in sensory-motor reactions was laid in a basis of experiment. Techniques of definition of individual characters of the sensori-motor asymmetries were used, and G. Ajzenk's questionnaire EPQ adapted by Prisniakova L. Time of sensorimotor reaction has significant distinctions between representatives of different types of temperament with a various level interchemishere asymmetry OF male and female cosmonauts. With increase in expressiveness of the right hemisphere time of reaction tends to reduction at representatives of all types of temperament, the number of erroneous reactions as a whole increases also a level of achievement tends to reduction. Results of time of sensorimotor reaction correspond with parameter L. Prisniakova which characterizes individual - psychological features. .Earlier the received experimental data of constant time of processing of the information in memory at a period of a sensorimotor reactions of the man and new results for women were used for calculation of these time constants for overloads distinct from terrestrial. These data enable to predict dynamics of behavior of cosmonauts with differing sex in conditions of flight in view of their individual characteristics connected with the hemisphere asymmetry of a brain and with by a various degree of lateralization.

  15. Association between Therapy Outcome and Right-Hemispheric Activation in Chronic Aphasia (United States)

    Richter, Maria; Miltner, Wolfgang H. R.; Straube, Thomas


    The role of the right hemisphere for language processing and successful therapeutic interventions in aphasic patients is a matter of debate. This study explored brain activation in right-hemispheric areas and left-hemispheric perilesional areas in response to language tasks in chronic non-fluent aphasic patients before and after constraint-induced…

  16. Task-free MRI predicts individual differences in brain activity during task performance

    NARCIS (Netherlands)

    Tavor, I.; Jones, O.P.; Mars, R.B.; Smith, S.M.; Behrens, T.E.J.; Jbabdi, S.


    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent

  17. Differences in brain function and changes with intervention in children with poor spelling and reading abilities. (United States)

    Gebauer, Daniela; Fink, Andreas; Kargl, Reinhard; Reishofer, Gernot; Koschutnig, Karl; Purgstaller, Christian; Fazekas, Franz; Enzinger, Christian


    Previous fMRI studies in English-speaking samples suggested that specific interventions may alter brain function in language-relevant networks in children with reading and spelling difficulties, but this research strongly focused on reading impaired individuals. Only few studies so far investigated characteristics of brain activation associated with poor spelling ability and whether a specific spelling intervention may also be associated with distinct changes in brain activity patterns. We here investigated such effects of a morpheme-based spelling intervention on brain function in 20 children with comparatively poor spelling and reading abilities using repeated fMRI. Relative to 10 matched controls, children with comparatively poor spelling and reading abilities showed increased activation in frontal medial and right hemispheric regions and decreased activation in left occipito-temporal regions prior to the intervention, during processing of a lexical decision task. After five weeks of intervention, spelling and reading comprehension significantly improved in the training group, along with increased activation in the left temporal, parahippocampal and hippocampal regions. Conversely, the waiting group showed increases in right posterior regions. Our findings could indicate an increased left temporal activation associated with the recollection of the new learnt morpheme-based strategy related to successful training.

  18. Behavioral and Physiological Findings of Gender Differences in Global-Local Visual Processing (United States)

    Roalf, David; Lowery, Natasha; Turetsky, Bruce I.


    Hemispheric asymmetries in global-local visual processing are well-established, as are gender differences in cognition. Although hemispheric asymmetry presumably underlies gender differences in cognition, the literature on gender differences in global-local processing is sparse. We employed event related brain potential (ERP) recordings during…

  19. Phase lags of solar hemispheric cycles

    CERN Document Server

    Muraközy, J


    The North-South asymmetry of solar activity is variable in time and strength. We analyse the long-term variation of the phase lags of hemispheric cycles and check a conjectured relationship between these phase lags and the hemispheric cycle strengths. Sunspot data are used from cycles 12-23 in which the separation of northern and southern hemispheres is possible. The centers of mass of the hemispheric cycle profiles were used to study the phase relations and relative strengths of the hemispheric cycles. This approach considers a cycle as a whole and disregards the short-term fluctuations of the cycle time profile. The phase of the hemispheric cycles shows an alternating variation: the northern cycle leads in 4 cycles and follows in 4 cycles. No significant relationship is found between the phase and strength differences of the hemispheric cycles. The period of 4+4 cycles appears to be close to the Gleissberg cycle and may provide a key to its physical background. It may raise a new aspect in the solar dynamo ...

  20. Human subcortical brain asymmetries in 15,847 people worldwide reveal effects of age and sex

    NARCIS (Netherlands)

    Zwiers, M.P.; Buitelaar, J.K.; Fernandez, G.S.E.; Flor, H.; Fouche, J.P.; Frouin, V.; Wolfers, T.; Fisher, S.E.; Francks, C.


    The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymm

  1. Methods of dichotic listening as a research methodology for hemispheric interaction.

    Directory of Open Access Journals (Sweden)

    Kovyazina M.S.


    Full Text Available Experimental data was obtained from a dichotic listening test by patients with unilateral brain lesions and corpus callosum pathology (agenesis, cysts, degenerative changes, etc. Efficiency index analysis shows that interhemispheric interaction in the audioverbal sphere depends to a greater extent on the right hemisphere state. The dichotic listening technique is not an informative means of studying hemispheric interaction, since it does not allow a clear distinction between hemispheric symptoms and symptoms of pathology of the corpus callosum. Thus, violations of hemispheric relations caused by disorders of the corpus callosum and cerebral hemispheres change worth more right hemisphere activity.

  2. Developmental differences in the brain response to unhealthy food cues

    NARCIS (Netherlands)

    Meer, van Floor; Laan, van der Laura N.; Charbonnier, Lisette; Viergever, Max A.; Adan, Roger A.H.; Smeets, Paul A.M.


    Background: Food cues are omnipresent and may trigger overconsumption. In the past 2 decades, the prevalence of childhood obesity has increased dramatically. Because children’s brains are still developing, especially in areas important for inhibition, children may be more susceptible than adults to

  3. Modeling of Brain Shift Phenomenon for Different Craniotomies and Solid Models

    Directory of Open Access Journals (Sweden)

    Alvaro Valencia


    Full Text Available This study investigates the effects of different solid models on predictions of brain shift for three craniotomies. We created a generic 3D brain model based on healthy human brain and modeled the brain parenchyma as single continuum and constrained by a practically rigid skull. We have used elastic model, hyperelastic 1st, 2nd, and 3rd Ogden models, and hyperelastic Mooney-Rivlin with 2- and 5-parameter models. A pressure on the brain surface at craniotomy region was applied to load the model. The models were solved with the finite elements package ANSYS. The predictions on stress and displacements were compared for three different craniotomies. The difference between the predictions of elastic solid model and a hyperelastic Ogden solid model of maximum brain displacement and maximum effective stress is relevant.

  4. Expression of alcoholism-relevant genes in the liver are differently correlated to different parts of the brain. (United States)

    Wang, Lishi; Huang, Yue; Jiao, Yan; Chen, Hong; Cao, Yanhong; Bennett, Beth; Wang, Yongjun; Gu, Weikuan


    The purpose of this study is to investigate whether expression profiles of alcoholism-relevant genes in different parts of the brain are correlated differently with those in the liver. Four experiments were conducted. First, we used gene expression profiles from five parts of the brain (striatum, prefrontal cortex, nucleus accumbens, hippocampus, and cerebellum) and from liver in a population of recombinant inbred mouse strains to examine the expression association of 10 alcoholism-relevant genes. Second, we conducted the same association analysis between brain structures and the lung. Third, using five randomly selected, nonalcoholism-relevant genes, we conducted the association analysis between brain and liver. Finally, we compared the expression of 10 alcoholism-relevant genes in hippocampus and cerebellum between an alcohol preference strain and a wild-type control. We observed a difference in correlation patterns in expression levels of 10 alcoholism-relevant genes between different parts of the brain with those of liver. We then examined the association of gene expression between alcohol dehydrogenases (Adh1, Adh2, Adh5, and Adh7) and different parts of the brain. The results were similar to those of the 10 genes. Then, we found that the association of those genes between brain structures and lung was different from that of liver. Next, we found that the association patterns of five alcoholism-nonrelevant genes were different from those of 10 alcoholism-relevant genes. Finally, we found that the expression level of 10 alcohol-relevant genes is influenced more in hippocampus than in cerebellum in the alcohol preference strain. Our results show that the expression of alcoholism-relevant genes in liver is differently associated with the expression of genes in different parts of the brain. Because different structural changes in different parts of the brain in alcoholism have been reported, it is important to investigate whether those structural differences in

  5. Spatial disorientation in right-hemisphere infarction.


    Meerwaldt, J D; van Harskamp, F


    Spatial orientation was tested with the rod orientation test. The subjects were 40 normal controls and 68 brain-damaged patients with cerebral infarcts. Patients in whom the lesion included the post-rolandic region of the right hemisphere performed worse than controls or patients with lesions at other sites. Patients with an exclusively postrolandic (usually occipital) lesion showed higher error rates than patients with a combined prerolandic and postrolandic lesion, but only for the visual p...

  6. Atypical right hemisphere specialization for object representations in an adolescent with specific language impairment

    Directory of Open Access Journals (Sweden)

    Timothy T. Brown


    Full Text Available Individuals with a diagnosis of specific language impairment (SLI show abnormal spoken language occurring alongside normal nonverbal abilities. Behaviorally, people with SLI exhibit diverse profiles of impairment involving phonological, grammatical, syntactic, and semantic aspects of language. In this study, we used a multimodal neuroimaging technique called anatomically constrained magnetoencephalography (aMEG to measure the dynamic functional brain organization of an adolescent with SLI. Using single-subject statistical maps of cortical activity, we compared this patient to a sibling and to a cohort of typically developing subjects during the performance of tasks designed to evoke semantic representations of concrete objects. Localized, real-time patterns of brain activity within the language impaired patient showed marked differences from the typical functional organization, with significant engagement of right hemisphere heteromodal cortical regions generally homotopic to the left hemisphere areas that usually show the greatest activity for such tasks. Functional neuroanatomical differences were evident at early sensoriperceptual processing stages and continued through later cognitive stages, observed specifically at latencies typically associated with semantic encoding operations. Our findings show with real-time temporal specificity evidence for an atypical right hemisphere specialization for the representation of concrete entities, independent of verbal motor demands. More broadly, our results demonstrate the feasibility and potential utility of using aMEG to characterize individual patient differences in the dynamic functional organization of the brain.

  7. Brain energy metabolism and blood flow differences in healthy aging

    DEFF Research Database (Denmark)

    Aanerud, Joel; Borghammer, Per; Chakravarty, M Mallar


    Cerebral metabolic rate of oxygen consumption (CMRO(2)), cerebral blood flow (CBF), and oxygen extraction fraction (OEF) are important indices of healthy aging of the brain. Although a frequent topic of study, changes of CBF and CMRO(2) during normal aging are still controversial, as some authors...... find decreases of both CBF and CMRO(2) but increased OEF, while others find no change, and yet other find divergent changes. In this reanalysis of previously published results from positron emission tomography of healthy volunteers, we determined CMRO(2) and CBF in 66 healthy volunteers aged 21 to 81......, and in the temporal cortex. Because of the inverse relation between OEF and capillary oxygen tension, increased OEF can compromise oxygen delivery to neurons, with possible perturbation of energy turnover. The results establish a possible mechanism of progression from healthy to unhealthy brain aging, as the regions...

  8. Inter-hemispheric competition relieved in both: hypotheses for autism and schizophrenia from problem theory. (United States)

    Burnand, Gordon


    A logical relationship exists among six general problems that people face in life. Using hope about something for its subjective probability, its expected likelihood, the problems form a series where the method of assessing hope changes in a simple manner from one problem to the next. The central hypothesis is that human beings exploit this. Brain structures and predispositions have evolved accordingly, leading to the hemispheres having different predispositions. The hemispheres are effectively joined at 5 months. Infants will then find that they engage in two unrelated activities. Typical infants label the activities in detail, using visual images, as part of gaining control over them. Hypotheses are: (a) autistic children fail labelling at the start, and hence they encounter uncontrolled competition between the hemispheres; (b) with some, serotonin abnormality impairs sensory information processing and hence the labelling; (c) with some, a delay in myelination from autoimmune effects disrupts labelling; (d) the likelihood of this 'delay autism' is reduced by long chain omega oils; (e) self-pressuring, which underlies taking on challenges and play like Hide and Seek, brings relief from the competition by raising the influence of one side; (f) the same left-right competition occurs in confused episodes and schizophrenia in vulnerable people who encounter pressures to use both hemispheres at the same time; (g) some symptoms raise the influence on one side ideationally. This leads to coherent theories of autism and schizophrenia. In both competition between the hemispheres is relieved primarily by self-pressuring, which raises influence on one side.

  9. Hemispheric preference in visuospatial processing: a complementary approach with fMRI and lesion studies. (United States)

    Ng, V W; Eslinger, P J; Williams, S C; Brammer, M J; Bullmore, E T; Andrew, C M; Suckling, J; Morris, R G; Benton, A L


    Historically, the left cerebral hemisphere has been considered specialized for language, whereas the right cerebral hemisphere is aligned with spatial processes. However, studies have called into question adherence to this model and suggested that both hemispheres participate in language and spatial cognition. Using functional Magnetic Resonance Imaging (fMRI) and human brain lesion studies, we determined whether these complementary techniques could clarify issues of hemispheric dominance. Using a modified Benton Judgement of Line Orientation (JLO) test, considered a relatively pure spatial processing task, we found robust and significant (p < 0.0005) bilateral superior parietal lobe activation on fMRI in ten right-handed male adult volunteers. This was corroborated by lesion data in a cohort of 17 patients who showed significant JLO impairments after either right or left parietal lobe damage, with right parietal damage associated with somewhat more severe deficit. Detailed wavelet analysis of the fMRI time-series did, however, reveal a more dominant role of the right parietal lobe in "kick-starting" the task. To our knowledge, this is a novel way of using fMRI to address functional hemispheric differences in a cognitive task that is known to have bilateral representation.

  10. Left hemisphere EEG coherence in infancy predicts infant declarative pointing and preschool epistemic language. (United States)

    Kühn-Popp, N; Kristen, S; Paulus, M; Meinhardt, J; Sodian, B


    Pointing plays a central role in preverbal communication. While imperative pointing aims at influencing another person's behavior, declarative gestures serve to convey epistemic information and to share interest in an object. Further, the latter are hypothesized to be a precursor ability of epistemic language. So far, little is known about their underlying brain maturation processes. Therefore, the present study investigated the relation between brain maturation processes and the production of imperative and declarative motives as well as epistemic language in N = 32 infants. EEG coherence scores were measured at 14 months, imperative and declarative point production at 15 months and epistemic language at 48 months. Results of correlational analyses suggest distinct behavioral and neural patterns for imperative and declarative pointing, with declarative pointing being associated with the maturation of the left hemisphere. Further, EEG coherence measures of the left hemisphere at 14 months and declarative pointing at 15 months are related to individual differences in epistemic language skills at 48 months, independently of child IQ. In regression analyses, coherence measures of the left hemisphere prove to be the most important predictor of epistemic language skills. Thus, neural processes of the left hemisphere seem particularly relevant to social communication.

  11. Computed tomographic findings in cerebral palsy: Analysis of hemisphere and lateral ventricular volume

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seoung Hwan; Kim, Hak Jin; Sol, Chang Hyo; Kim, Byung Soo [Pusan National University College of Medicine, Pusan (Korea, Republic of)


    Authors analysed the CT findings of 28 cerebral palsy patients at Pusan National University Hospital from January, 1984 to December, 1987. Volumes of hemispheres, lateral ventricles and paranchymes were measured in patients who showed no remarkable abnormality on CT film, and compared with those of normal control group. 1. Among the 28 cerebral palsy patients, there were 6 cases of diffuse atrophy in CT findings, and unilateral atrophy in 2 cases and encephalomalacia and diffuse white matter low density in 1 case and generalized symmetrical white matter low density in 1 case, but remaining 18 cases had no specific abnormal finding on CT. 2. Difference in volumes of brain parenchyma and lateral ventricles of each hemisphere was greater than that of control group. 3. There were more enlarged lateral ventricles and prominent unilateral brain atrophy in 18 cases of cerebral palsy who showed no specific abnormality on CT as compared with normal control group.

  12. Task-free MRI predicts individual differences in brain activity during task performance. (United States)

    Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S


    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.

  13. Acetamiprid Accumulates in Different Amounts in Murine Brain Regions

    Directory of Open Access Journals (Sweden)

    Hayato Terayama


    Full Text Available Neonicotinoids such as acetamiprid (ACE belong to a new and widely used single class of pesticides. Neonicotinoids mimic the chemical structure of nicotine and share agonist activity with the nicotine acetylcholine receptor (nAchR. Neonicotinoids are widely considered to be safe in humans; however, they have recently been implicated in a number of human health disorders. A wide range of musculoskeletal and neuromuscular disorders associated with high doses of neonicotinoids administered to animals have also been reported. Consequently, we used a mouse model to investigate the response of the central nervous system to ACE treatment. Our results show that exposure to ACE-containing water for three or seven days (decuple and centuple of no observable adverse effect level (NOAEL/day caused a decrease in body weight in 10-week old A/JJmsSlc (A/J mice. However, the treatments did not affect brain histology or expression of CD34. ACE concentrations were significantly higher in the midbrain of ACE-treated mice than that of the normal and vehicle groups. Expression levels of α7, α4, and β2 nAChRs were found to be low in the olfactory bulb and midbrain of normal mice. Furthermore, in the experimental group (centuple ACE-containing water for seven days, β2 nAChR expression decreased in many brain regions. Information regarding the amount of accumulated ACE and expression levels of the acetylcholine receptor in each region of the brain is important for understanding any clinical symptoms that may be associated with ACE exposure.

  14. Acetamiprid Accumulates in Different Amounts in Murine Brain Regions (United States)

    Terayama, Hayato; Endo, Hitoshi; Tsukamoto, Hideo; Matsumoto, Koichi; Umezu, Mai; Kanazawa, Teruhisa; Ito, Masatoshi; Sato, Tadayuki; Naito, Munekazu; Kawakami, Satoshi; Fujino, Yasuhiro; Tatemichi, Masayuki; Sakabe, Kou


    Neonicotinoids such as acetamiprid (ACE) belong to a new and widely used single class of pesticides. Neonicotinoids mimic the chemical structure of nicotine and share agonist activity with the nicotine acetylcholine receptor (nAchR). Neonicotinoids are widely considered to be safe in humans; however, they have recently been implicated in a number of human health disorders. A wide range of musculoskeletal and neuromuscular disorders associated with high doses of neonicotinoids administered to animals have also been reported. Consequently, we used a mouse model to investigate the response of the central nervous system to ACE treatment. Our results show that exposure to ACE-containing water for three or seven days (decuple and centuple of no observable adverse effect level (NOAEL)/day) caused a decrease in body weight in 10-week old A/JJmsSlc (A/J) mice. However, the treatments did not affect brain histology or expression of CD34. ACE concentrations were significantly higher in the midbrain of ACE-treated mice than that of the normal and vehicle groups. Expression levels of α7, α4, and β2 nAChRs were found to be low in the olfactory bulb and midbrain of normal mice. Furthermore, in the experimental group (centuple ACE-containing water for seven days), β2 nAChR expression decreased in many brain regions. Information regarding the amount of accumulated ACE and expression levels of the acetylcholine receptor in each region of the brain is important for understanding any clinical symptoms that may be associated with ACE exposure. PMID:27669271

  15. Conjugating Time and Frequency: Hemispheric Specialization, Acoustic Uncertainty, and the Mustached Bat

    Directory of Open Access Journals (Sweden)

    Stuart Dante Washington


    Full Text Available A prominent hypothesis of hemispheric specialization for human speech and music, states that the left and right auditory cortices (ACs are respectively specialized for precise calculation of two canonically-conjugate variables: time and frequency. This spectral-temporal asymmetry does not account for sex, brain-volume, or handedness, and is in opposition to closed-system hypotheses that restrict this asymmetry to humans. Mustached bats have smaller brains, but greater ethological pressures to develop such a spectral-temporal asymmetry, than humans. Using the Heisenberg-Gabor Limit (i.e., the mathematical basis of the spectral-temporal asymmetry to frame mustached bat literature, we show that recent findings in bat AC (1 support the notion that hemispheric specialization for speech and music is based on hemispheric differences in temporal and spectral resolution, (2 discredit closed-system, handedness, and brain-volume theories, (3 underscore the importance of sex differences, and (4 provide new avenues for phonological research.

  16. Preliminary notes on brain weight variation across labrid fish species with different levels of cooperative behaviour

    Institute of Scientific and Technical Information of China (English)

    Marta C.SOARES; Gon(c)alo I.ANDR(E); José R.PAULA


    Brain size and weight vary tremendously in the animal kingdom.It has been suggested that brain structural development must evolve balanced between the advantages of dealing with greater social challenges and the energetic costs of maintaining and developing larger brains.Here we ask if interspecific differences in cooperative behaviour ( behaviour) are related to brain weight variations in four close-related species of Labrid fish:two are obligatory cleanerfish throughout their entire life (Labroides dimidiatus and L.bicolor),one facultative cleaner fish Labropsis australis and one last species that never engage in cleaning Labrichthys unilineatus.We first search for the link between the rate of species' cooperation and its relative brain weight,and finally,if the degree of social complexity and cooperation are reflected in the weight of its major brain substructures.Overall,no differences were found in relative brain weight (in relation to body weight) across species.Fine-scale differences were solely demonstrated for the facultative cleaner L.australis,at the brainstem level.Furthermore,data visual examination indicates that the average cerebellum and brainstem weights appear to be larger for L.dimidiatus.Because variation was solely found at specific brain areas (such as cerebellum and brainstem) and not for the whole brain weight values,it suggests that species social-ecological and cognitive demands may be directly contributing to a selective investment in relevant brain areas.This study provides first preliminary evidence that links potential differences in cognitive ability in cooperative behaviour to how these may mediate the evolution of brain structural development in non-mammal vertebrate groups [Current Zoology 61 (2):274-280,2015].

  17. Different Brain Wave Patterns and Cortical Control Abilities in Relation to Different Creative Potentials (United States)

    Li, Ying-Han; Tseng, Chao-Yuan; Tsai, Arthur Chih-Hsin; Huang, Andrew Chih-Wei; Lin, Wei-Lun


    Contemporary understanding of brain functions provides a way to probe into the mystery of creativity. However, the prior evidence regarding the relationship between creativity and brain wave patterns reveals inconsistent conclusions. One possible reason might be that the means of selecting creative individuals in the past has varied in each study.…

  18. Brain SCALE: brain structure and cognition: an adolescent longitudinal twin study into the genetic etiology of individual differences. (United States)

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


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

  19. Interspecies avian brain chimeras reveal that large brain size differences are influenced by cell-interdependent processes. (United States)

    Chen, Chun-Chun; Balaban, Evan; Jarvis, Erich D


    Like humans, birds that exhibit vocal learning have relatively delayed telencephalon maturation, resulting in a disproportionately smaller brain prenatally but enlarged telencephalon in adulthood relative to vocal non-learning birds. To determine if this size difference results from evolutionary changes in cell-autonomous or cell-interdependent developmental processes, we transplanted telencephala from zebra finch donors (a vocal-learning species) into Japanese quail hosts (a vocal non-learning species) during the early neural tube stage (day 2 of incubation), and harvested the chimeras at later embryonic stages (between 9-12 days of incubation). The donor and host tissues fused well with each other, with known major fiber pathways connecting the zebra finch and quail parts of the brain. However, the overall sizes of chimeric finch telencephala were larger than non-transplanted finch telencephala at the same developmental stages, even though the proportional sizes of telencephalic subregions and fiber tracts were similar to normal finches. There were no significant changes in the size of chimeric quail host midbrains, even though they were innervated by the physically smaller zebra finch brain, including the smaller retinae of the finch eyes. Chimeric zebra finch telencephala had a decreased cell density relative to normal finches. However, cell nucleus size differences between each species were maintained as in normal birds. These results suggest that telencephalic size development is partially cell-interdependent, and that the mechanisms controlling the size of different brain regions may be functionally independent.

  20. Interspecies avian brain chimeras reveal that large brain size differences are influenced by cell-interdependent processes.

    Directory of Open Access Journals (Sweden)

    Chun-Chun Chen

    Full Text Available Like humans, birds that exhibit vocal learning have relatively delayed telencephalon maturation, resulting in a disproportionately smaller brain prenatally but enlarged telencephalon in adulthood relative to vocal non-learning birds. To determine if this size difference results from evolutionary changes in cell-autonomous or cell-interdependent developmental processes, we transplanted telencephala from zebra finch donors (a vocal-learning species into Japanese quail hosts (a vocal non-learning species during the early neural tube stage (day 2 of incubation, and harvested the chimeras at later embryonic stages (between 9-12 days of incubation. The donor and host tissues fused well with each other, with known major fiber pathways connecting the zebra finch and quail parts of the brain. However, the overall sizes of chimeric finch telencephala were larger than non-transplanted finch telencephala at the same developmental stages, even though the proportional sizes of telencephalic subregions and fiber tracts were similar to normal finches. There were no significant changes in the size of chimeric quail host midbrains, even though they were innervated by the physically smaller zebra finch brain, including the smaller retinae of the finch eyes. Chimeric zebra finch telencephala had a decreased cell density relative to normal finches. However, cell nucleus size differences between each species were maintained as in normal birds. These results suggest that telencephalic size development is partially cell-interdependent, and that the mechanisms controlling the size of different brain regions may be functionally independent.

  1. Right hemisphere reading in a case of developmental deep dyslexia


    Funnell, Elaine; Pitchford, Nicola; de Haan, Bianca; Morgan, Paul


    The right hemisphere hypothesis of deep dyslexia has received support from functional imaging studies of acquired deep dyslexia following damage to the left cerebral hemisphere, but no imaging studies of cases of developmental deep dyslexia, in which brain damage is not suspected, have been reported. In this paper, we report the first evidence of right hyperactivation in an adult case of developmental deep dyslexia. Hyperactivation was observed in the right inferior frontal cortex during fMRI...

  2. Population differences in brain morphology and microstructure among Chinese, Malay, and Indian neonates.

    Directory of Open Access Journals (Sweden)

    Jordan Bai

    Full Text Available We studied a sample of 75 Chinese, 73 Malay, and 29 Indian healthy neonates taking part in a cohort study to examine potential differences in neonatal brain morphology and white matter microstructure as a function of ethnicity using both structural T2-weighted magnetic resonance imaging (MRI and diffusion tensor imaging (DTI. We first examined the differences in global size and morphology of the brain among the three groups. We then constructed the T2-weighted MRI and DTI atlases and employed voxel-based analysis to investigate ethnic differences in morphological shape of the brain from the T2-weighted MRI, and white matter microstructure measured by fractional anisotropy derived from DTI. Compared with Malay neonates, the brains of Indian neonates' tended to be more elongated in anterior and posterior axis relative to the superior-inferior axis of the brain even though the total brain volume was similar among the three groups. Although most anatomical regions of the brain were similar among Chinese, Malay, and Indian neonates, there were anatomical variations in the spinal-cerebellar and cortical-striatal-thalamic neural circuits among the three populations. The population-related brain regions highlighted in our study are key anatomical substrates associated with sensorimotor functions.

  3. Differences in {sup 99m}Tc-HMPAO brain SPET perfusion imaging between Tourette's syndrome and chronic tic disorder in children

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, N.-T.; Lee, B.-F. [Dept. of Nuclear Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan (Taiwan); Chang, Y.-C. [Dept. of Pediatrics, Kaohsiung Chang Kang Children' s Hospital, Kaohsiung, Taiwan (Taiwan); Huang, C.-C. [Dept. of Pediatrics, College of Medicine, National Cheng Kung University, Tainan (Taiwan); Wang, S.-T. [Dept. of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan (Taiwan)


    Early differential diagnosis between Tourette's syndrome and chronic tic disorder is difficult but important because both the outcome and the treatment of these two childhood-onset diseases are distinct. We assessed the sensitivity and specificity of brain single-photon emission tomography (SPET) perfusion imaging in distinguishing the two diseases, and characterized their different cerebral perfusion patterns. Twenty-seven children with Tourette's syndrome and 11 with chronic tic disorder (mean age 9.5 and 8.6 years, respectively) underwent brain SPET with technetium-99m hexamethylpropylene amine oxime (HMPAO). Visual interpretation and semi-quantitative analysis of SPET images were performed. On visual interpretation, 22 of 27 (82%) of the Tourette's syndrome group had lesions characterized by decreased perfusion. The left hemisphere was more frequently involved. None of the children with chronic tic disorder had a visible abnormality. Semi-quantitative analysis showed that, compared with children with chronic tic disorder, children with Tourette's syndrome had significantly lower perfusion in the left lateral temporal area and asymmetric perfusion in the dorsolateral frontal, lateral and medial temporal areas. In conclusion, using the visual approach, brain SPET perfusion imaging is sensitive and specific in differentiating Tourette's syndrome and chronic tic disorder. The perfusion difference between the two groups, demonstrated by semi-quantitative analysis, may be related more to the co-morbidity in Tourette's syndrome than to tics per se. (orig.)

  4. Preliminary Study on Delta-9-Tetrahydrocannabinol (∆9-THC: Hemispheric Lateralization with Behavioural Changes

    Directory of Open Access Journals (Sweden)

    Noor Azuin Suliman


    Full Text Available This study is designed inspired by the fact that there is an interhemisphere asymmetry of the brain region. A lot of researches studied in demonstrating the differences between right and left hemispheres of the brain. The objective of this preliminary study is to observe scientifically the effect of delta-9-tetrahydrocannabinol (∆9-THC on the hemispheric lateralization with behavioural changes. Two regions of brain are selected, prefrontal cortex and hippocampus. Behavioural tests, namely heat stress test and novel-object discrimination test (NOD, were done on day seven. The hippocampus and prefrontal cortex regions of the brain were preceded to Western Blot technique in detecting c-fos. As for behavioural tests, heat stress and NOD and c-fos on hippocampus did not show significant differences. Meanwhile, the prefrontal cortex shows significant difference with p < 0.01. With these findings, reasonable dosages of ∆9-THC should be used to have statistically significant differences effects on behavioural tests. 

  5. Neuromagnetic index of hemispheric asymmetry predicting long-term outcome in sudden hearing loss. (United States)

    Li, Lieber Po-Hung; Chen, Kuang-Chao; Lee, Po-Lei; Niddam, David M; Cheng, Chou-Ming; Chou, Chih-Cher; Hsieh, Jen-Chuen; Shiao, An-Suey


    The neuromagnetic index of hemispheric asymmetry in terms of ipsilateral/contralateral ratio at acute stage was previously revealed to prognosticate the 1-month hearing outcome of acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL), showing a dynamic relationship between top- and down-levels of auditory pathway. However, the prognostic effect of reorganization pattern for the long-term results remained elusive. This study aimed to probe the prognosticating relevance of hemispheric asymmetry to the hearing at chronic stage of ISSNHL. Using magnetoencephalography (MEG), inter-hemispheric differences in peak dipole of N100m responses to monaural tones were evaluated in 21 controls and 21 ISSNHL patients at initial and final (12 months later) stages. Predictive value of hemispheric asymmetry was assessed by correlating hearing level and ipsilateral/contralateral ratio (I/C) of N100m latency and amplitude. Healthy-side dominance of N100m was observed in ISSNHL initially, and remained in three final prognostic subgroups (complete, partial, and no recovery) of ISSNHL. The initial I/C(amplitude) on affected-ear stimulation strongly correlated with the hearing level of final stage in ISSNHL. However, there was no prognostic effect of hemispheric asymmetry pattern for the 12-month hearing improvement. The heterogeneity between neuromagnetic index and hearing levels possibly echoed different pathogeneses of ISSNHL. Since a restored hearing status did not necessarily lead toward a normal functional organization, the dynamics of hemispheric asymmetry could actually index a central resilient reorganization in the brain for sound processing in ISSNHL. Our finding showed not only a clinically relevant measure to predict final hearing of ISSNHL, but also a linkage between central plasticity and cochlear lesion. This finding suggests a new perspective, and perhaps new interventions, to diagnose and treat unilateral ISSNHL.

  6. Divergent structural brain abnormalities between different genetic subtypes of children with Prader–Willi syndrome


    Lukoshe, Akvile; White, Tonya; Schmidt, Marcus N.; van der Lugt, Aad; Hokken-Koelega, Anita C.


    Background Prader–Willi syndrome (PWS) is a complex neurogenetic disorder with symptoms that indicate not only hypothalamic, but also a global, central nervous system (CNS) dysfunction. However, little is known about developmental differences in brain structure in children with PWS. Thus, our aim was to investigate global brain morphology in children with PWS, including the comparison between different genetic subtypes of PWS. In addition, we performed exploratory cortical and subcortical foc...

  7. Superficial white matter: effects of age, sex, and hemisphere. (United States)

    Phillips, Owen R; Clark, Kristi A; Luders, Eileen; Azhir, Ramin; Joshi, Shantanu H; Woods, Roger P; Mazziotta, John C; Toga, Arthur W; Narr, Katherine L


    Structural and diffusion imaging studies demonstrate effects of age, sex, and asymmetry in many brain structures. However, few studies have addressed how individual differences might influence the structural integrity of the superficial white matter (SWM), comprised of short-range association (U-fibers), and intracortical axons. This study thus applied a sophisticated computational analysis approach to structural and diffusion imaging data obtained from healthy individuals selected from the International Consortium for Brain Mapping (ICBM) database across a wide adult age range (n=65, age: 18-74 years, all Caucasian). Fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) were sampled and compared at thousands of spatially matched SWM locations and within regions-of-interest to examine global and local variations in SWM integrity across age, sex, and hemisphere. Results showed age-related reductions in FA that were more pronounced in the frontal SWM than in the posterior and ventral brain regions, whereas increases in RD and AD were observed across large areas of the SWM. FA was significantly greater in left temporoparietal regions in men and in the posterior callosum in women. Prominent leftward FA and rightward AD and RD asymmetries were observed in the temporal, parietal, and frontal regions. Results extend previous findings restricted to the deep white matter pathways to demonstrate regional changes in the SWM microstructure relating to processes of demyelination and/or to the number, coherence, or integrity of axons with increasing age. SWM fiber organization/coherence appears greater in the left hemisphere regions spanning language and other networks, while more localized sex effects could possibly reflect sex-specific advantages in information strategies.

  8. Is hemispheric language dominance relevant in musical hallucinations? Two case reports. (United States)

    Evers, Stefan; Ellger, Tanja; Ringelstein, Erich B; Knecht, Stefan


    It has been suggested that musical hallucinations are often due to a focal brain lesion predominantly of right hemispheric pathologies. We report about two patients with musical hallucinations associated with a brain tumor of the right hemisphere. Although both patients were right-handed, one of them had a right hemispheric dominance for language as proven by the Wada test. The musical ability as measured by the Seashore test was not impaired. We conclude that the language dominance of the hemisphere is not primarily relevant for the development of musical hallucinations.

  9. New insights into differences in brain organization between Neanderthals and anatomically modern humans. (United States)

    Pearce, Eiluned; Stringer, Chris; Dunbar, R I M


    Previous research has identified morphological differences between the brains of Neanderthals and anatomically modern humans (AMHs). However, studies using endocasts or the cranium itself are limited to investigating external surface features and the overall size and shape of the brain. A complementary approach uses comparative primate data to estimate the size of internal brain areas. Previous attempts to do this have generally assumed that identical total brain volumes imply identical internal organization. Here, we argue that, in the case of Neanderthals and AMHs, differences in the size of the body and visual system imply differences in organization between the same-sized brains of these two taxa. We show that Neanderthals had significantly larger visual systems than contemporary AMHs (indexed by orbital volume) and that when this, along with their greater body mass, is taken into account, Neanderthals have significantly smaller adjusted endocranial capacities than contemporary AMHs. We discuss possible implications of differing brain organization in terms of social cognition, and consider these in the context of differing abilities to cope with fluctuating resources and cultural maintenance.

  10. A positron emission tomography analysis of glucose metabolism in Alzheimer's disease brain using [F-18] fluorodeoxyglucose : A parallel study with elemental concentrations

    NARCIS (Netherlands)

    Cutts, DA; Spyrou, NM; Maguire, RP; Stedman, JD; Leenders, KL


    Alzheimer's disease (AD) isa debilitating form of dementia which leads to impaired memory, thinking and behavior. This work examines elemental concentrations between "normal" and AD subjects as well as the hemispherical differences within the brain. Tissue samples from both hemispheres of the fronta

  11. Secondary hyperalgesia phenotypes exhibit differences in brain activation during noxious stimulation

    DEFF Research Database (Denmark)

    Asghar, Mohammad Sohail; Pereira, Manuel Pedro; Werner, Mads Utke;


    . To study differences in the propensity to develop central sensitization we examined differences in brain activity and anatomy according to individual phenotypical expression of secondary hyperalgesia by magnetic resonance imaging. Forty healthy volunteers received a first-degree burn-injury (47 °C, 7 min...... hyperalgesia areas after burn-injury. In addition, T1-weighted images were used to measure differences in gray-matter density in cortical and subcortical regions of the brain. We found significant differences in neuronal activity between high- and low-sensitization responders at baseline (before application...... in high-sensitization responders in comparison to low-sensitization responders. These findings suggest that brain-structure and neuronal activation to noxious stimulation differs according to secondary hyperalgesia phenotype. This indicates differences in central sensitization according to phenotype...

  12. Comparison of five different targeting ligands to enhance accumulation of liposomes into the brain. (United States)

    van Rooy, Inge; Mastrobattista, Enrico; Storm, Gert; Hennink, Wim E; Schiffelers, Raymond M


    In many different studies nanocarriers modified with targeting ligands have been used to target to the brain. Many ligands have been successful, but it is difficult to compare results from different studies to determine which targeting ligand is the best. Therefore, we selected five targeting ligands (transferrin, RI7217, COG133, angiopep-2, and CRM197) and compared their ability to target liposomes to the brain in vitro and in vivo. In vitro, only CRM197-modified liposomes were able to bind to murine endothelial cells (bEnd.3). Both CRM197 and RI7217-modified liposomes associated with human endothelial cells (hCMEC/D3). In vivo, uptake of targeted liposomes was tested at 12h after iv injection. For some of the ligands, additional time points of 1 and 6h were tested. Only the RI7217 was able to significantly enhance brain uptake in vivo at all time points. Uptake in the brain capillaries was up to 10 times higher compared to untargeted liposomes, and uptake in the brain parenchyma was up to 4.3 times higher. Additionally, these results show that many targeting ligands that have been described for brain targeting, do not target to the brain in vivo when coupled to a liposomal delivery vehicle.

  13. Uptake and biodistribution of rizatriptan to blood and brain following different routes of administration in rats. (United States)

    Wang, Chun; Quan, Li-Hui; Guo, Yi; Liu, Chun-Yu; Liao, Yong-Hong


    The objective of the present study was to investigate the biodistribution profiles of rizatriptan in the blood and brain of Wistar rats after peroral, subcutaneous, intranasal and intratracheal administration with a particular view to determining the applicability of inhalation delivery to achieve rapid and high availability of the drug in both blood and the brain. Following the intratracheal administration of the drug (4.0mg/kg) to the rats, the absolute bioavailability was found to be 91.2%, significantly higher than those from intranasal or peroral routes, and T(max) in plasma and brain was attained within 2 min, significantly shorter than the T(max) of intranasal ( approximately 10 min in both plasma and brain), subcutaneous (16.7 min in plasma and 22.5 min in brain) and peroral (30.0 min in plasma and 45.0 min in brain) administration. In addition, other pharmacokinetic parameters associated with rapid onset of action including AUC(plasma/brain) and C(max), of intratracheal instillated rizatriptan appeared also to be comparable or superior to those of other delivered routes. Although AUC(brain)/AUC(plasma) ratios after intranasal delivery (43.4%) differed significantly from the ratios shown after intratracheal instillation (23.2%), the AUC(brain 0-120 min) via the latter routes was slightly but not significantly higher than that from the former routes. The results in the present study indicated that pulmonary delivery of rizatriptan may achieve maximum plasma and brain concentrations significantly more rapidly compared with intranasal, subcutaneous and peroral administration and be a promising delivery method with extremely rapid onset of action in the pain relief of migraine.

  14. Brain Function Differences in Language Processing in Children and Adults with Autism



    Comparison of brain function between children and adults with autism provides an understanding of the effects of the disorder and associated maturational differences on language processing. Functional imaging (functional magnetic resonance imaging) was used to examine brain activation and cortical synchronization during the processing of literal and ironic texts in 15 children with autism, 14 children with typical development, 13 adults with autism, and 12 adult controls. Both the children an...

  15. Loss of T cells influences sex differences in behavior and brain structure. (United States)

    Rilett, Kelly C; Friedel, Miriam; Ellegood, Jacob; MacKenzie, Robyn N; Lerch, Jason P; Foster, Jane A


    Clinical and animal studies demonstrate that immune-brain communication influences behavior and brain function. Mice lacking T cell receptor β and δ chains were tested in the elevated plus maze, open field, and light-dark test and showed reduced anxiety-like behavior compared to wild type. Interestingly sex differences were observed in the behavioural phenotype of TCRβ-/-δ- mice. Specifically, female TCRβ-/-δ- mice spent more time in the light chamber compared to wild type females, whereas male TCRβ-/-δ- spent more time in the center of the open field compared to wild type males. In addition, TCRβ-/-δ- mice did not show sex differences in activity-related behaviors observed in WT mice. Ex vivo brain imaging (7 Tesla MRI) revealed volume changes in hippocampus, hypothalamus, amygdala, periaqueductal gray, and dorsal raphe and other brain regions between wild type and T cell receptor knockout mice. There was also a loss of sexual dimorphism in brain volume in the bed nucleus of the stria terminalis, normally the most sexually dimorphic region in the brain, in immune compromised mice. These data demonstrate the presence of T cells is important in the development of sex differences in CNS circuitry and behavior.

  16. Distribution of α-asarone in brain following three different routes of administration in rats. (United States)

    Lu, Jin; Fu, Tingming; Qian, Yuyi; Zhang, Qichun; Zhu, Huaxu; Pan, Linmei; Guo, Liwei; Zhang, Meng


    The goal of the present paper is to compare the distributions of α-asarone administered to rats through three different routes: oral, intravenous and intranasal. The concentrations of α-asarone in seven distinct brain regions, the olfactory bulb, cerebellum, hypothalamus, frontal cortex, striatum, hippocampus and medulla/pons as well as in plasma and cerebrospinal fluid (CSF), were determined by HPLC. The quantities of α-asarone accumulated in liver were measured to determine whether α-asarone could generate hepatotoxicity when administered via the three different routes. The results indicated that α-asarone could be absorbed via two different routes into the brain, after intranasal administration of dry powders. In the systemic route, α-asarone immediately entered the brain through the blood-brain barrier (BBB) after uptake into the circulatory system. In the olfactory bulb route, α-asarone traveled from the olfactory epithelium in the nasal cavity straight into brain tissue via the olfactory bulb. Furthermore, intranasal administration of α-asarone as a dry powder can ensure quick absorption and avoid excessive concentrations in the blood and liver, while achieving concentrations in the brain comparable to those attained by intravenous and oral administration routes.

  17. Prediction of brain maturity based on cortical thickness at different spatial resolutions. (United States)

    Khundrakpam, Budhachandra S; Tohka, Jussi; Evans, Alan C


    Several studies using magnetic resonance imaging (MRI) scans have shown developmental trajectories of cortical thickness. Cognitive milestones happen concurrently with these structural changes, and a delay in such changes has been implicated in developmental disorders such as attention-deficit/hyperactivity disorder (ADHD). Accurate estimation of individuals' brain maturity, therefore, is critical in establishing a baseline for normal brain development against which neurodevelopmental disorders can be assessed. In this study, cortical thickness derived from structural magnetic resonance imaging (MRI) scans of a large longitudinal dataset of normally growing children and adolescents (n=308), were used to build a highly accurate predictive model for estimating chronological age (cross-validated correlation up to R=0.84). Unlike previous studies which used kernelized approach in building prediction models, we used an elastic net penalized linear regression model capable of producing a spatially sparse, yet accurate predictive model of chronological age. Upon investigating different scales of cortical parcellation from 78 to 10,240 brain parcels, we observed that the accuracy in estimated age improved with increased spatial scale of brain parcellation, with the best estimations obtained for spatial resolutions consisting of 2560 and 10,240 brain parcels. The top predictors of brain maturity were found in highly localized sensorimotor and association areas. The results of our study demonstrate that cortical thickness can be used to estimate individuals' brain maturity with high accuracy, and the estimated ages relate to functional and behavioural measures, underscoring the relevance and scope of the study in the understanding of biological maturity.

  18. Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia

    NARCIS (Netherlands)

    Langen, C.D.; White, T.; Ikram, M.A.; Vernooij, M.W.; Niessen, W.J.


    Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significan

  19. Hypofractionated stereotactic radiotherapy for brain metastases. Results from three different dose concepts

    Energy Technology Data Exchange (ETDEWEB)

    Fahrig, A.; Grabenbauer, G.; Sauer, R. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Ganslandt, O. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Dept. of Neurosurgery of the Univ. of Erlangen (Germany); Lambrecht, U. [Dept. of Radiation Therapy and Novalis Shaped Beam Surgery Center of the Univ. of Erlangen (Germany); Div. of Medical Physics of the Dept. of Radiation Therapy of the Univ. of Erlangen (Germany); Kleinert, G.; Hamm, K. [Dept. for Stereotactic Neurosurgery and Radiosurgery, Helios Klinikum Erfurt (Germany)


    Purpose: To evaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (hfSRT) with three different dose concepts for irresectable brain metastases not amenable to radiosurgery (SRS) using non-invasive fixation of the skull. Patients and Methods: From 6/2000 to 6/2005, 150 patients with 228 brain metastases were treated at the dedicated stereotactic radiosurgery system Novalis trademark (BrainLAB, Feldkirchen, Germany) in two German treatment centers. Three different dose concepts were applied: 5 x 6-7 Gy (A: 72 brain metastases), 10 x 4 Gy (B: 59 brain metastases) and 7 x 5 Gy (C: 97 brain metastases). Median planning target volume (PTV) was 6.1 cm{sup 3} (range, 0.02-95.97). Results: Rates of complete remission (CR), partial remission (PR), no change (NC) and progressive disease (PD) were 42%, 30%, 21% and 7%, respectively (median follow-up 28 months). Median survival was 16 months. Survival at 6 and 12 months was 83% and 66%, respectively. Side effects were dependent on the PTV and on dose concept (median PTV in case of increasing edema or necrosis: 17 cm{sup 3}, A: 22%, C: 7%). HfSRT with 10 x 4 Gy (B) was well tolerated without side effects. Conclusion: Hypofractionated stereotactic radiotherapy is an effective and safe treatment. In case of brain metastases > 15 cm{sup 3} (diameter > 3 cm) and concerning toxicity, 10 x 4 Gy seem to be more advantageous than shorter fractionation with higher doses while 5 x 6-7 Gy and 7 x 5 Gy were followed by higher response rates. Further specification of tolerance doses and tolerance according to the different brain regions has to be done. (orig.)

  20. Spatial disorientation in right-hemisphere infarction. (United States)

    Meerwaldt, J D; van Harskamp, F


    Spatial orientation was tested with the rod orientation test. The subjects were 40 normal controls and 68 brain-damaged patients with cerebral infarcts. Patients in whom the lesion included the post-rolandic region of the right hemisphere performed worse than controls or patients with lesions at other sites. Patients with an exclusively postrolandic (usually occipital) lesion showed higher error rates than patients with a combined prerolandic and postrolandic lesion, but only for the visual part of the test. These patients were re-examined one year after the stroke. Most of them showed an incomplete recovery of spatial function. PMID:7119828

  1. Repeated stressful experiences differently affect brain dopamine receptor subtypes

    Energy Technology Data Exchange (ETDEWEB)

    Puglisi-Allegra, S.; Cabib, S. (Istituto di Psicobiologia e Psicofarmacologia (CNR), Roma (Italy)); Kempf, E.; Schleef, C. (Centre de Neurochimi, Strasbourg (Italy))


    The binding of tritiated spiperone (D2 antagonist) and tritiated SCH 23390 (D1 antagonist), in vivo, was investigated in the caudatus putamen (CP) and nucleus accumbens septi (NAS) of mice submitted to ten daily restraint stress sessions. Mice sacrificed 24 hr after the last stressful experience presented a 64% decrease of D2 receptor density (Bmax) but no changes in D1 receptor density in the NAS. In the CP a much smaller (11%) reduction of D2 receptor density was accompanied by a 10% increase of D1 receptors. These results show that the two types of dopamine (DA) receptors adapt in different or even opposite ways to environmental pressure, leading to imbalance between them.

  2. Comparison of regional gene expression differences in the brains of the domestic dog and human

    Directory of Open Access Journals (Sweden)

    Kennerly Erin


    Full Text Available Abstract Comparison of the expression profiles of 2,721 genes in the cerebellum, cortex and pituitary gland of three American Staffordshire terriers, one beagle and one fox hound revealed regional expression differences in the brain but failed to reveal marked differences among breeds, or even individual dogs. Approximately 85 per cent (42 of 49 orthologue comparisons of the regional differences in the dog are similar to those that differentiate the analogous human brain regions. A smaller percentage of human differences were replicated in the dog, particularly in the cortex, which may generally be evolving more rapidly than other brain regions in mammals. This study lays the foundation for detailed analysis of the population structure of transcriptional variation as it relates to cognitive and neurological phenotypes in the domestic dog.

  3. Individual differences in brain structure and resting brain function underlie cognitive styles: evidence from the Embedded Figures Test. (United States)

    Hao, Xin; Wang, Kangcheng; Li, Wenfu; Yang, Wenjing; Wei, Dongtao; Qiu, Jiang; Zhang, Qinglin


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

    Directory of Open Access Journals (Sweden)

    Yu Sun

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

  5. Phase analysis of sunspot group numbers on both solar hemispheres

    Institute of Scientific and Technical Information of China (English)

    Lin-Hua Deng; Zhong-Quan Qu; Xiao-Li Yan; Kai-Rang Wang


    Cross-correlation analysis and wavelet transform methods are proposed to investigate the phase relationship between the monthly sunspot group numbers in the solar northern and southern hemispheres.It is found that (1) the monthly sunspot group numbers in the northern hemisphere begin two months earlier than those in the southern one,which should lead to phase asynchrony between them but with a slight effect; (2) the Schwabe cycle length for the monthly sunspot group numbers in the two hemispheres obviously differs from each other,and the mean Schwabe cycle length of the monthly sunspot group numbers in the northern hemisphere is slightly larger than that in the southern one; (3) the monthly sunspot group numbers in the northern hemisphere precede those in the southern hemisphere during the years of about 1874-1927,after which,the southern hemisphere leads the northern hemisphere in the years 1928-1964,and then the northern hemisphere leads in time till the present.

  6. Effects of different concentrations of pollen extract on brain tissues of Oncorhynchus mykiss

    Institute of Scientific and Technical Information of China (English)

    Mehmet Fuat Gulhan; Hasan Akgul; Taner Dastan; Sevgi Durna Dastan; Zeliha Selamoglu Talas


    Objective: To determine the antioxidant capacities of pollen extract applied at different concentrations on biochemical parameters in brain tissues of rainbow trouts. Methods:parameters in brain tissues of fish treated at various concentrations of the pollen extract (0.5, 2.5, 5, 10, 20 and 30 mg/L) for 96 h. The malondialdehyde levels, total antioxidant status, total oxidant status, oxidative stress index and amounts of total free sulfhydryl groups were analyzed in fish brain. Results:The effective concentration of pollen was determined with some biochemical treated compared to control group (P Conclusions: To apply the pollen to fish reduces the detrimental effects and modulates oxidative status via activating antioxidant defense systems at brain tissue. As a result, pollen can be added up to 10 mg/L to the medium of rainbow trout to improve health of fish.

  7. Brain Metastases from Different Primary Carcinomas: an Evaluation of DSC MRI Measurements. (United States)

    Zhang, H; Zhang, G; Oudkerk, M


    This study evaluated the roles of different dynamic susceptibility contrast magnetic imaging (DSC MRI) measurements in discriminating between brain metastases derived from four common primary carcinomas. Thirty-seven patients with brain metastases were enrolled. Relative cerebral blood volume (rCBV), cerebral blood flow (rCBF) and relative mean transit time (rMTT) in both tumor and peritumoral edema were measured. Metastases were grouped by their primary tumor (lung, gastrointestinal, breast and renal cell carcinoma). DSC MRI measurements were compared between groups. Mean rCBV, rCBF, rMTT in tumor and peritumoral edema of all brain metastases (n=37) were 2.79 ± 1.73, 2.56 ± 2.11, 1.21 ± 0.48 and 1.05 ± 0.53, 0.86 ± 0.40, 1.99 ± 0.41, respectively. The tumoral rCBV (5.26 ± 1.89) and rCBF (5.32 ± 3.28) of renal metastases were greater than those of the other three metastases (P0.05). Evaluating various DSC MRI measurements can provide complementary hemodynamic information on brain metastases. The tumoral rCBV, rCBF and likely rMTT can help discriminate between brain metastases originating from different primary carcinomas. The peritumoral DSC MRI measurements had limited value in discriminating between brain metastases.

  8. Are boys and girls that different? An analysis of traumatic brain injury in children.

    LENUS (Irish Health Repository)

    Collins, Niamh C


    The Phillips Report on traumatic brain injury (TBI) in Ireland found that injury was more frequent in men and that gender differences were present in childhood. This study determined when gender differences emerge and examined the effect of gender on the mechanism of injury, injury type and severity and outcome.

  9. Can the Differences between Education and Neuroscience Be Overcome by Mind, Brain, and Education? (United States)

    Samuels, Boba M.


    The new field of Mind, Brain, and Education (MBE)--sometimes called educational neuroscience--is posited as a mediator between neuroscience and education. Several foundational concerns, however, can be raised about this emerging field. The differences between neuroscience and education are many, including differences in their histories,…

  10. Peculiarities of brain electric activity in young males and females of different creativity levels

    Directory of Open Access Journals (Sweden)

    Ermakov, Pavel N.


    Full Text Available This article shows that the peculiarities of divergent and convergent thinking in young males and females of various creativity levels are stipulated by a definite EEG frequency-and-spatial arrangement. Young males and females of mixed and left lateral arrangement profiles demonstrate an expressed activity of occipital, central, and temporal areas of both cerebral hemispheres. In young males and females of right LAP (lateral arrangement profile, connections are clearly localized in case of solution of both convergent and divergent tasks. Solution of divergent and convergent tasks may condition certain frequency-and-spatial arrangement of EEG in young males and females with different levels of academic progress and a different lateral arrangement profile (LAP.

  11. Brain activation patterns at exhaustion in rats that differ in inherent exercise capacity.

    Directory of Open Access Journals (Sweden)

    Teresa E Foley

    Full Text Available In order to further understand the genetic basis for variation in inherent (untrained exercise capacity, we examined the brains of 32 male rats selectively bred for high or low running capacity (HCR and LCR, respectively. The aim was to characterize the activation patterns of brain regions potentially involved in differences in inherent running capacity between HCR and LCR. Using quantitative in situ hybridization techniques, we measured messenger ribonuclease (mRNA levels of c-Fos, a marker of neuronal activation, in the brains of HCR and LCR rats after a single bout of acute treadmill running (7.5-15 minutes, 15° slope, 10 m/min or after treadmill running to exhaustion (15-51 minutes, 15° slope, initial velocity 10 m/min. During verification of trait differences, HCR rats ran six times farther and three times longer prior to exhaustion than LCR rats. Running to exhaustion significantly increased c-Fos mRNA activation of several brain areas in HCR, but LCR failed to show significant elevations of c-Fos mRNA at exhaustion in the majority of areas examined compared to acutely run controls. Results from these studies suggest that there are differences in central c-Fos mRNA expression, and potential brain activation patterns, between HCR and LCR rats during treadmill running to exhaustion and these differences could be involved in the variation in inherent running capacity between lines.

  12. The corpus callosum in primates: processing speed of axons and the evolution of hemispheric asymmetry (United States)

    Phillips, Kimberley A.; Stimpson, Cheryl D.; Smaers, Jeroen B.; Raghanti, Mary Ann; Jacobs, Bob; Popratiloff, Anastas; Hof, Patrick R.; Sherwood, Chet C.


    Interhemispheric communication may be constrained as brain size increases because of transmission delays in action potentials over the length of axons. Although one might expect larger brains to have progressively thicker axons to compensate, spatial packing is a limiting factor. Axon size distributions within the primate corpus callosum (CC) may provide insights into how these demands affect conduction velocity. We used electron microscopy to explore phylogenetic variation in myelinated axon density and diameter of the CC from 14 different anthropoid primate species, including humans. The majority of axons were less than 1 µm in diameter across all species, indicating that conduction velocity for most interhemispheric communication is relatively constant regardless of brain size. The largest axons within the upper 95th percentile scaled with a progressively higher exponent than the median axons towards the posterior region of the CC. While brain mass among the primates in our analysis varied by 97-fold, estimates of the fastest cross-brain conduction times, as conveyed by axons at the 95th percentile, varied within a relatively narrow range between 3 and 9 ms across species, whereas cross-brain conduction times for the median axon diameters differed more substantially between 11 and 38 ms. Nonetheless, for both size classes of axons, an increase in diameter does not entirely compensate for the delay in interhemispheric transmission time that accompanies larger brain size. Such biophysical constraints on the processing speed of axons conveyed by the CC may play an important role in the evolution of hemispheric asymmetry. PMID:26511047

  13. Metabolic control of resting hemispheric cerebral blood flow is oxidative, not glycolytic. (United States)

    Powers, William J; Videen, Tom O; Markham, Joanne; Walter, Vonn; Perlmutter, Joel S


    Although the close regional coupling of resting cerebral blood flow (CBF) with both cerebral metabolic rate of oxygen (CMRO(2)) and cerebral metabolic rate of glucose (CMRglc) within individuals is well documented, there are few data regarding the coupling between whole brain flow and metabolism among different subjects. To investigate the metabolic control of resting whole brain CBF, we performed multivariate analysis of hemispheric CMRO(2), CMRglc, and other covariates as predictors of resting CBF among 23 normal humans. The univariate analysis showed that only CMRO(2) was a significant predictor of CBF. The final multivariate model contained two additional terms in addition to CMRO(2): arterial oxygen content and oxygen extraction fraction. Notably, arterial plasma glucose concentration and CMRglc were not included in the final model. Our data demonstrate that the metabolic factor controlling hemispheric CBF in the normal resting brain is CMRO(2) and that CMRglc does not make a contribution. Our findings provide evidence for compartmentalization of brain metabolism into a basal component in which CBF is coupled to oxygen metabolism and an activation component in which CBF is controlled by another mechanism.

  14. Summary of high field diffusion MRI and microscopy data demonstrate microstructural aberration in chronic mild stress rat brain

    DEFF Research Database (Denmark)

    Khan, Ahmad Raza; Chuhutin, Andrey; Wiborg, Ove


    Abstract This data article describes a large, high resolution diffusion MRI data set from fixed rat brain acquired at high field strength. The rat brain samples consist of21adult rat brain hemispheres from animals exposed to chronic mild stress (anhedonic and resilient) and controls. Histology from...... amygdala of the same brain hemispheres is also included with three different stains: DiI and Hoechst stained microscopic images (confocal microscopy) andALDH1L1 antibody based immunohistochemistry.These stains may be used to evaluate neurite density (DiI), nuclear density (Hoechst) and astrocytic density...

  15. Moral values are associated with individual differences in regional brain volume. (United States)

    Lewis, Gary J; Kanai, Ryota; Bates, Timothy C; Rees, Geraint


    Moral sentiment has been hypothesized to reflect evolved adaptations to social living. If so, individual differences in moral values may relate to regional variation in brain structure. We tested this hypothesis in a sample of 70 young, healthy adults examining whether differences on two major dimensions of moral values were significantly associated with regional gray matter volume. The two clusters of moral values assessed were "individualizing" (values of harm/care and fairness) and "binding" (deference to authority, in-group loyalty, and purity/sanctity). Individualizing was positively associated with left dorsomedial pFC volume and negatively associated with bilateral precuneus volume. For binding, a significant positive association was found for bilateral subcallosal gyrus and a trend to significance for the left anterior insula volume. These findings demonstrate that variation in moral sentiment reflects individual differences in brain structure and suggest a biological basis for moral sentiment, distributed across multiple brain regions.

  16. Same task, different strategies: how brain networks can be influenced by memory strategy. (United States)

    Sanfratello, Lori; Caprihan, Arvind; Stephen, Julia M; Knoefel, Janice E; Adair, John C; Qualls, Clifford; Lundy, S Laura; Aine, Cheryl J


    Previous functional neuroimaging studies demonstrated that different neural networks underlie different types of cognitive processing by engaging participants in particular tasks, such as verbal or spatial working memory (WM) tasks. However, we report here that even when a WM task is defined as verbal or spatial, different types of memory strategies may be used to complete it, with concomitant variations in brain activity. We developed a questionnaire to characterize the type of strategy used by individual members in a group of 28 young healthy participants (18-25 years) during a spatial WM task. A cluster analysis was performed to differentiate groups. We acquired functional magnetoencephalography and structural diffusion tensor imaging measures to characterize the brain networks associated with the use of different strategies. We found two types of strategies were used during the spatial WM task, a visuospatial and a verbal strategy, and brain regions and time courses of activation differed between participants who used each. Task performance also varied by type of strategy used with verbal strategies showing an advantage. In addition, performance on neuropsychological tests (indices from Wechsler Adult Intelligence Scale-IV, Rey Complex Figure Test) correlated significantly with fractional anisotropy measures for the visuospatial strategy group in white matter tracts implicated in other WM and attention studies. We conclude that differences in memory strategy can have a pronounced effect on the locations and timing of brain activation and that these differences need further investigation as a possible confounding factor for studies using group averaging as a means for summarizing results.

  17. Physiological and psychological individual differences influence resting brain function measured by ASL perfusion. (United States)

    Kano, M; Coen, S J; Farmer, A D; Aziz, Q; Williams, S C R; Alsop, D C; Fukudo, S; O'Gorman, R L


    Effects of physiological and/or psychological inter-individual differences on the resting brain state have not been fully established. The present study investigated the effects of individual differences in basal autonomic tone and positive and negative personality dimensions on resting brain activity. Whole-brain resting cerebral perfusion images were acquired from 32 healthy subjects (16 males) using arterial spin labeling perfusion MRI. Neuroticism and extraversion were assessed with the Eysenck Personality Questionnaire-Revised. Resting autonomic activity was assessed using a validated measure of baseline cardiac vagal tone (CVT) in each individual. Potential associations between the perfusion data and individual CVT (27 subjects) and personality score (28 subjects) were tested at the level of voxel clusters by fitting a multiple regression model at each intracerebral voxel. Greater baseline perfusion in the dorsal anterior cingulate cortex (ACC) and cerebellum was associated with lower CVT. At a corrected significance threshold of p personality traits (amygdala, caudate, etc.) during active task processing. The resting brain state may therefore need to be taken into account when interpreting the neurobiology of individual differences in structural and functional brain activity.

  18. Electro-acupuncture at different acupoints modulating the relative specific brain functional network (United States)

    Fang, Jiliang; Wang, Xiaoling; Wang, Yin; Liu, Hesheng; Hong, Yang; Liu, Jun; Zhou, Kehua; Wang, Lei; Xue, Chao; Song, Ming; Liu, Baoyan; Zhu, Bing


    Objective: The specific brain effects of acupoint are important scientific concern in acupuncture. However, previous acupuncture fMRI studies focused on acupoints in muscle layer on the limb. Therefore, researches on acupoints within connective tissue at trunk are warranted. Material and Methods: Brain effects of acupuncture on abdomen at acupoints Guanyuan (CV4) and Zhongwan (CV12) were tested using fMRI on 21 healthy volunteers. The data acquisition was performed at resting state, during needle retention, electroacupuncture (EA) and post-EA resting state. Needling sensations were rated after every electroacupuncture (EA) procedure. The needling sensations and the brain functional activity and connectivity were compared between CV4 and CV12 using SPSS, SPM2 and the local and remote connectivity maps. Results and conclusion: EA at CV4 and CV12 induced apparent deactivation effects in the limbic-paralimbic-neocortical network. The default mode of the brain was modified by needle retention and EA, respectively. The functional brain network was significantly changed post EA. However, the minor differences existed between these two acupoints. The results demonstrated similarity between functional brain network mode of acupuncture modulation and functional circuits of emotional and cognitive regulation. Acupuncture may produce analgesia, anti-anxiety and anti-depression via the limbic-paralimbic-neocortical network (LPNN).

  19. Right Hemisphere Dominance for Emotion Processing in Baboons (United States)

    Wallez, Catherine; Vauclair, Jacques


    Asymmetries of emotional facial expressions in humans offer reliable indexes to infer brain lateralization and mostly revealed right hemisphere dominance. Studies concerned with oro-facial asymmetries in nonhuman primates largely showed a left-sided asymmetry in chimpanzees, marmosets and macaques. The presence of asymmetrical oro-facial…

  20. Lateral thinkers are not so laterally minded: hemispheric asymmetry, interaction, and creativity. (United States)

    Lindell, Annukka K


    The biological basis of creativity remains a topic of contention. A long-held view suggests that whereas the left hemisphere is intelligent and analytic, the right hemisphere is the source of all creativity. Consequently, activating the right hemisphere should enhance creative thinking, prompting a plethora of popular books hawking a right hemisphere solution to topics ranging from drawing, to money management, to sex. More recently, an alternate proposal has suggested that creativity is not a lateralised function; instead, creativity is argued to stem from the interaction and integration of information across both the left and right hemispheres. According to this view, individuals with greater interhemispheric communication and/or less-lateralised brains will evidence enhanced creative ability. This paper reviews the neural basis of creativity to determine whether creativity stems from activation of the right hemisphere, or from the interaction of both hemispheres. The relationship between creativity and psychopathology is also examined, evaluating the evidence for a causal link between disorders such as schizophrenia, hemispheric activation, and enhanced creativity. Although the research reviewed indicates greater right hemisphere activity during creative tasks, the interaction between many varied, often distant, cortical regions across both the left and right hemispheres is also a crucial component of creativity. This interaction facilitates the integration of a variety of separate cognitive abilities, fostering creative thinking. As such, creativity is better conceptualised as a distributed, rather than a purely lateralised, function; more lateral thinkers have less lateralised brains.

  1. Hospital acquired pneumonia is linked to right hemispheric peri-insular stroke.

    Directory of Open Access Journals (Sweden)

    André Kemmling

    Full Text Available PURPOSE: Hospital acquired pneumonia (HAP is a major complication of stroke. We sought to determine associations between infarction of specific brain regions and HAP. METHODS: 215 consecutive acute stroke patients with HAP (2003-2009 were carefully matched with 215 non-pneumonia controls by gender, then NIHSS, then age. Admission imaging and binary masks of infarction were registered to MNI-152 space. Regional atlas and voxel-based log-odds were calculated to assess the relationship between infarct location and the likelihood of HAP. An independently validated penalized conditional logistic regression model was used to identify HAP associated imaging regions. RESULTS: The HAP and control patients were well matched by gender (100%, age (95% within 5-years, NIHSS (98% within 1-point, infarct size, dysphagia, and six other clinical variables. Right hemispheric infarcts were more frequent in patients with HAP versus controls (43.3% vs. 34.0%, p = 0.054, whereas left hemispheric infarcts were more frequent in controls (56.7% vs. 44.7%, p = 0.012; there was no significant difference between groups in the rate of brainstem strokes (p = 1.0. Of the 10 most infarcted regions, only right insular cortex volume was different in HAP versus controls (20 vs. 12 ml, p = 0.02. In univariate analyses, the highest log-odds regions for pneumonia were right hemisphere, cerebellum, and brainstem. The best performing multivariate model selected 7 brain regions of infarction and 2 infarct volume-based variables independently associated with HAP. CONCLUSIONS: HAP is associated with right hemispheric peri-insular stroke. These associations may be related to autonomic modulation of immune mechanisms, supporting recent hypotheses of stroke mediated immune suppression.

  2. Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia


    Langen, Carolyn D.; Tonya White; Arfan Ikram, M.; Vernooij, Meike W.; Niessen, Wiro J.


    Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, "bi-modal comparison plots" show the distribution of uni- and bi-modal group differences and the relationshi...

  3. Biochemical markers of apoptosis in different parts of the brain during learning. (United States)

    Sherstnev, V V; Yurasov, V V; Storozheva, Z I; Gruden', M A; Yakovleva, N E


    Caspase-3 activity and the levels of DNA fragments of 200-600 and >4000 b.p. were estimated in the cerebellar vermis, the hippocampus, and the prefrontal cortex of the brains of adult rats four and 24 months after training to extinction of the acoustic startle reaction and conditioned fear. Differently timed changes in the levels of biochemical markers of apoptosis were seen to different extents in these brain areas after training. These changes were characterized by a decrease in caspase-3 activity in the cerebellar vermis and the hippocampus, with decreases in DNA fragmentation in the hippocampus and cerebral cortex and increases in measures of programmed cell death in the hypothalamus. These experimental data support the view that the apoptosis of cells in the mature brain is involved in the mechanisms of learning and memory.

  4. Communicating with the non-dominant hemisphere Implications for neurological rehabilitation

    Institute of Scientific and Technical Information of China (English)

    Fabricio Ferreira de Oliveira; Sheilla de Medeiros Correia Marin; Paulo Henrique Ferreira Bertolucci


    Aphasic syndromes usually result from injuries to the dominant hemisphere of the brain. Despite the fact that localization of language functions shows little interindividual variability, several brain areas are simultaneously activated when language tasks are undertaken. Mechanisms of language recovery after brain injury to the dominant hemisphere seem to be relatively stereotyped, including activations of perilesional areas in the acute phase and of homologues of language areas in the non-dominant hemisphere in the subacute phase, later returning to dominant hemisphere activation in the chronic phase. Plasticity mechanisms reopen the critical period of language development, more specifically in what leads to disinhibition of the non-dominant hemisphere when brain lesions affect the dominant hemisphere. The non-dominant hemisphere plays an important role during recovery from aphasia, but currently available rehabilitation therapies have shown limited results for efficient language improvement. Large-scale randomized controlled trials that evaluate well-defined interventions in patients with aphasia are needed for stimulation of neuroplasticity mechanisms that enhance the role of the non-dominant hemisphere for language recovery. Ineffective treatment approaches should be replaced by more promising ones and the latter should be evaluated for proper application. The data generated by such studies could substantiate evidence-based rehabilitation strategies for patients with aphasia.

  5. Stereological Volumetry of Cere-bral Hemispheres and Lateral Ventricles Using MRI in Schizophrenia Subtypes

    Directory of Open Access Journals (Sweden)

    H. Haghir


    Full Text Available Background/Objectives: The structural changes of brain (cerebral and lateral ventricles volumes in schizophrenia are controversial. This is partly due to the heterogenicity of the schizophrenia subtypes. In this study we compared the changes in the volumes of cerebral hemispheres and lateral ventricles in 3 subtypes of schizophrenia (paranoid, undifferentiated and residual with normal controls. Materials and Methods: 29 schizophrenia patients (21 men, 8 women of 3 subtypes of paranoid, undifferentiated, and residual (according to DMS-IV criteria were compared with 29 age- and gender-matched normal controls. All cases and controls underwent 3-D brain MRI of full coronal series, 1.5 mm slices without interslice gaps. The hemispheres and lateral ventricles were outlined and their volumes were calculated using Cavalieri’s Principle. The results were statistically analyzed. Results: The brain was slightly but insignificantly smaller in the schizophrenia patients. Only the residual subtype showed a significant reduction in cerebral and hemispheric volumes than controls (p<0.05. The volumes of right and left ventricle, separately and together were larger than controls (p<0.03. The ventricle-to-brain ratios (VBRs were greater in the cases (p<0.05. The paranoid subtype patients had larger ventricles and VBRs than controls (p<0.05. The lateral ventricle volumes and VBRs in the undifferentiated subtype were similar to the controls. In the residual subtypes, the ventricular volumes were similar to and the VBRs were larger than controls (p<0.05. Conclusion: Schizophrenia is a heterogeneous disorder regarding its symptoms and neuropathological changes. The patterns of change in the cerebral and ventricular volumes differed in the studied 3 subtypes.

  6. Attenuation of Oxidative Damage by Boerhaavia diffusa L. Against Different Neurotoxic Agents in Rat Brain Homogenate. (United States)

    Ayyappan, Prathapan; Palayyan, Salin Raj; Kozhiparambil Gopalan, Raghu


    Due to a high rate of oxidative metabolic activity in the brain, intense production of reactive oxygen metabolite occurs, and the subsequent generation of free radicals is implicated in the pathogenesis of traumatic brain injury, epilepsy, and ischemia as well as chronic neurodegenerative diseases. In the present study, protective effects of polyphenol rich ethanolic extract of Boerhaavia diffusa (BDE), a neuroprotective edible medicinal plant against oxidative stress induced by different neurotoxic agents, were evaluated. BDE was tested against quinolinic acid (QA), 3-nitropropionic acid (NPA), sodium nitroprusside (SNP), and Fe (II)/EDTA complex induced oxidative stress in rat brain homogenates. QA, NPA, SNP, and Fe (II)/EDTA treatment caused an increased level of thiobarbituric acid reactive substances (TBARS) in brain homogenates along with a decline in the activities of antioxidant enzymes. BDE treatment significantly decreased the production of TBARS (p tissues. Therefore, B. diffusa had high antioxidant potential that could inhibit the oxidative stress induced by different neurotoxic agents in brain. Since many of the neurological disorders are associated with free radical injury, these data may imply that B. diffusa, functioning as an antioxidant agent, may be beneficial for reducing various neurodegenerative complications.

  7. Contralesional motor deficits after unilateral stroke reflect hemisphere-specific control mechanisms


    Mani, Saandeep; Mutha, Pratik K.; Przybyla, Andrzej; Haaland, Kathleen Y.; Good, David C.; Sainburg, Robert L.


    We have proposed a model of motor lateralization, in which the left and right hemispheres are specialized for different aspects of motor control: the left hemisphere for predicting and accounting for limb dynamics and the right hemisphere for stabilizing limb position through impedance control mechanisms. Our previous studies, demonstrating different motor deficits in the ipsilesional arm of stroke patients with left or right hemisphere damage, provided a critical test of our model. However, ...

  8. A MEMS diamond hemispherical resonator (United States)

    Bernstein, J. J.; Bancu, M. G.; Cook, E. H.; Chaparala, M. V.; Teynor, W. A.; Weinberg, M. S.


    In this paper we report the fabrication of hemispherical polycrystalline diamond resonators fabricated on a novel high-temperature glass substrate. The hemispherical resonator gyroscope is one of the most accurate and rugged of the mechanical gyroscopes, and can be operated in either rate or whole-angle mode due to its high degree of symmetry. A fabrication sequence for creating extremely symmetric 3D MEMS hemispheres is presented. Mode shapes and frequencies obtained with a laser vibrometer are shown, as well as curves of Q versus pressure, and the dependence of frequency on anchor size. Fundamental mode frequency matching to gyroscope operation in whole-angle mode.

  9. Framing effects: the influence of handedness and access to right hemisphere processing. (United States)

    Stein, Jeannette M


    Changing how information is framed, such that the same critical information is cast in a positive or negative light, has a powerful impact on judgements and decision making. Research indicates that the influence of frames may be driven by participants' initial affective response and that the right hemisphere is sensitive to the emotional connotation of stimuli. While previous research tested the effects of hemispheric differences on framing effects by inducing asymmetrical activation, the current study explored how stable brain differences may account for differences in susceptibility to framing effects. Because mixed degree of handedness is associated with increased access to right hemisphere processes, mixed-handed participants were expected to be more susceptible to the effects of framing than strong-handed participants. Participants responded to the Asian disease problem and completed as assessment of handedness. Although mixed- and strong-handed participants were affected differently, the results were not consistent with the hypothesis. Mixed-handed participants conformed to risky choice framing effects when options were framed negatively and showed no effect of the positive frame. Strong-handed participants conformed to positively framed options and showed no effect of the negative frame. Possible explanations are discussed.

  10. Sex-based differences in brain alterations across chronic pain conditions. (United States)

    Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A


    Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current Mini-Review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex articles were identified from among 412 chronic pain neuroimaging articles. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared with male chronic pain patients: differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large-scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. © 2016 Wiley Periodicals, Inc.

  11. Time Perception in Severe Traumatic Brain Injury Patients: A Study Comparing Different Methodologies (United States)

    Mioni, G.; Mattalia, G.; Stablum, F.


    In this study, we investigated time perception in patients with traumatic brain injury (TBI). Fifteen TBI patients and 15 matched healthy controls participated in the study. Participants were tested with durations above and below 1s on three different temporal tasks that involved time reproduction, production, and discrimination tasks. Data…

  12. Twin-singleton differences in brain structure using structural equation modelling

    NARCIS (Netherlands)

    Pol, HEH; Posthuma, D; Baare, WFC; De Geus, EJC; Schnack, HG; van Haren, NEM; van Oel, CJ; Kahn, RS; Boomsma, DI


    Twin studies are important to investigate genetic influences on variation in human brain morphology in health and disease. However, the twin method has been criticized for its alleged non-generalizability due to differences in the intrauterine and family environment of twins, compared with singleton

  13. CMB-S4 and the Hemispherical Variance Anomaly

    CERN Document Server

    O'Dwyer, Marcio; Knox, Lloyd; Starkman, Glenn D


    Cosmic Microwave Background (CMB) full-sky temperature data show a hemispherical asymmetry in power nearly aligned with the Ecliptic. In real space, this anomaly can be quantified by the temperature variance in the northern and southern Ecliptic hemispheres. In this context, the northern hemisphere displays an anomalously low variance while the southern hemisphere appears unremarkable (consistent with expectations from the best-fitting theory, $\\Lambda$CDM). While this is a well established result in temperature, the low signal-to-noise ratio in current polarization data prevents a similar comparison. This will change with a proposed ground-based CMB experiment, CMB-S4. With that in mind, we generate realizations of polarization maps constrained by the temperature data and predict the distribution of the hemispherical variance in polarization considering two different sky coverage scenarios possible in CMB-S4: full Ecliptic north coverage and just the portion of the North that can be observed from a ground ba...

  14. Theories of inter-hemispheric interactions in aphasia: the role of tDCS in rehabilitation of post-stroke aphasia

    Directory of Open Access Journals (Sweden)

    Roy H Hamilton


    Full Text Available Mounting data from behavioral and neuroimaging studies have shown that the process of recovery from aphasia is largely driven by the reorganization of brain networks related to language. Evidence implicates a variety of potential mechanisms in this reorganization, some of which involve substantive changes in brain functional activity within and between cerebral hemispheres. These changes include intrahemispheric recruitment of perilesional left-hemisphere regions and transcallosal interhemispheric interactions between lesioned left-hemisphere language areas and homologous regions in the right hemisphere. With respect to the role of the right hemisphere, it is debated whether interhemispheric interactions are beneficial or deleterious to recovering language networks. Recent years have also seen the emergence of noninvasive brain stimulation techniques such as transcranial magnetic stimulation (TMS and transcranial direct current stimulation (tDCS as potential novel treatments for post-stroke aphasia. Because these techniques are predicated on either focal excitation or inhibition of brain areas, characterization of the functional roles of the left and right hemispheres and transcallosal interactions in aphasia recovery is of central importance to the development and refinement of stimulation-based therapies. However, most treatment studies involving noninvasive brain stimulation in aphasia have tacitly accepted the interhemispheric inhibition model, in which right hemisphere activity interferes with language recovery that is mediated by left hemisphere perisylvian regions. Based on this account, many studies in aphasia involving TMS and tDCS have adopted one of two approaches consistent with the model: left hemisphere excitation or right hemisphere inhibition. In this presentation, we will review both clinical and cognitive neuroscience evidence that elucidates different hemispheric mechanisms that influence recovery from aphasia after stroke

  15. Features of microelement maintenance in rat's brain tissues at experimental hypoxia of different degree.

    Directory of Open Access Journals (Sweden)

    Tarasova I.V.


    Full Text Available Features of microelement maintenance (iron, zinc, copper, manganese, and cobalt, conditionally toxic chrome and toxic lead were studied in newborn rat's brain tissues at experimental hypoxia of different degree. Tissues of newborn rat’s brain are characterized by high level of saturation and considerable dynamism of microelement maintenance. Till the end of the first week of life, the maintenance of these microelements decreases in 1,5 – 10 times. The level of the toxic lead decreases more than in 2,5 times. The hypoxia of easy degree of newborn rats invokes reduction cobalt level 3 times, iron level 2 times, manganese – on 27,65 %, chrome – on 25,84%, zinc – on 16,43%. It means that considerable deficiency and disbalance of microelement maintenance rat's brain tissues. The heavy degree of hypoxia is characterized by further increase of deficiency and disbalance of microelements.


    Kovalchuk, Yu P; Prischepa, I V; Si, U; Nedzvetsky, V S; Kot, Y G; Persky, E E; Ushakova, G A


    The chronic effects of low doses of cadmium on the distribution of soluble and filament forms of glial fibrillary acidic protein (GFAP) and their polypeptide fragments in different parts of the rat brain were investigated. Obtained results showed dose-dependent effect of cadmium on the soluble form of GFAP and more pronounced effect on the filament form and composition of the polypeptide fragments of the protein in the rat brain. Prolonged intoxication by cadmium ions in a dose of 1.0 μg/kg of body weight induced a significant decrease in soluble GFAP and an increase in the filament form in the rat brain, pointing to the development of reactive astrogliosis and the risk of neurodegeneration.

  17. Expression of alpha-synuclein in different brain parts of adult and aged rats. (United States)

    Adamczyk, A; Solecka, J; Strosznajder, J B


    The synucleins are a family of presynaptic proteins that are abundant in neurons and include alpha-, beta, and gamma-synuclein. Alpha-synuclein (ASN) is involved in several neurodegenerative age-related disorders but its relevance in physiological aging is unknown. In the present study we investigated the expression of ASN mRNA and protein in the different brain parts of the adult (4-month-old) and aged (24-month-old) rats by using RT-PCR technique and Western blot, respectively. Our results indicated that mRNA expression and immunoreactivity of ASN is similar in brain cortex, hippocampus and striatum but markedly lower in cerebellum comparing to the other brain parts. Aging lowers ASN mRNA expression in striatum and cerebellum by about 40%. The immunoreactivity of ASN in synaptic plasma membranes (SPM) from aged brain cortex, hippocampus and cerebellum is significantly lower comparing to adult by 39%, 24% and 65%, respectively. Beta-synuclein (BSN) was not changed in aged brain comparing to adult. Age-related alteration of ASN may affect the nerve terminals structure and function.

  18. Propofol Affects Different Human Brain Regions Depending on Depth of Sedation

    Institute of Scientific and Technical Information of China (English)

    Xiang Quan; Tie-hu Ye; Si-fang Lin; Liang Zou; Shou-yuan Tian


    Objective To investigate the effect of propofol on brain regions at different sedation levels and the association between changes in brain region activity and loss of consciousness using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) and bispectral index (BIS) monitoring. Methods Forty-eight participants were enrolled at Peking Union Medical College Hospital from October 2011 to March 2012 and randomly assigned to a mild or a deep sedation group using computer- generated random numbers. Preliminary tests were performed a week prior to scanning to determine target effect site concentrations based on BIS and concomitant Observer's Assessment of Alertness/Sedation scores while under propofol. Within one week of the preliminary tests where propofol dose-response was established, BOLD-fMRI was conducted to examine brain activation with the subject awake, and with propofol infusion at the sedation level. Results Mild propofol sedation inhibited left inferior parietal lobe activation. Deep sedation inhibited activation of the left insula, left superior temporal gyrus, and right middle temporal gyrus. Compared with mild sedation, deep propofol sedation inhibited activation of the left thalamus, precentral gyrus, anterior cingulate, and right basal nuclei. Conclusion Mild and deep propofol sedation are associated with inhibition of different brain regions, possibly explaining differences in the respective loss of consciousness processes.

  19. Psychoacoustic tinnitus loudness and tinnitus-related distress show different associations with oscillatory brain activity.

    Directory of Open Access Journals (Sweden)

    Tobias Balkenhol

    Full Text Available BACKGROUND: The phantom auditory perception of subjective tinnitus is associated with aberrant brain activity as evidenced by magneto- and electroencephalographic studies. We tested the hypotheses (1 that psychoacoustically measured tinnitus loudness is related to gamma oscillatory band power, and (2 that tinnitus loudness and tinnitus-related distress are related to distinct brain activity patterns as suggested by the distinction between loudness and distress experienced by tinnitus patients. Furthermore, we explored (3 how hearing impairment, minimum masking level, and (4 psychological comorbidities are related to spontaneous oscillatory brain activity in tinnitus patients. METHODS AND FINDINGS: Resting state oscillatory brain activity recorded electroencephalographically from 46 male tinnitus patients showed a positive correlation between gamma band oscillations and psychoacoustic tinnitus loudness determined with the reconstructed tinnitus sound, but not with the other psychoacoustic loudness measures that were used. Tinnitus-related distress did also correlate with delta band activity, but at electrode positions different from those associated with tinnitus loudness. Furthermore, highly distressed tinnitus patients exhibited a higher level of theta band activity. Moreover, mean hearing loss between 0.125 kHz and 16 kHz was associated with a decrease in gamma activity, whereas minimum masking levels correlated positively with delta band power. In contrast, psychological comorbidities did not express significant correlations with oscillatory brain activity. CONCLUSION: Different clinically relevant tinnitus characteristics show distinctive associations with spontaneous brain oscillatory power. Results support hypothesis (1, but exclusively for the tinnitus loudness derived from matching to the reconstructed tinnitus sound. This suggests to preferably use the reconstructed tinnitus spectrum to determine psychoacoustic tinnitus loudness

  20. Brain functional connectivity changes in children that differ in impulsivity temperamental trait. (United States)

    Inuggi, Alberto; Sanz-Arigita, Ernesto; González-Salinas, Carmen; Valero-García, Ana V; García-Santos, Jose M; Fuentes, Luis J


    Impulsivity is a core personality trait forming part of normal behavior and contributing to adaptive functioning. However, in typically developing children, altered patterns of impulsivity constitute a risk factor for the development of behavioral problems. Since both pathological and non-pathological states are commonly characterized by continuous transitions, we used a correlative approach to investigate the potential link between personality and brain dynamics. We related brain functional connectivity of typically developing children, measured with magnetic resonance imaging at rest, with their impulsivity scores obtained from a questionnaire completed by their parents. We first looked for areas within the default mode network (DMN) whose functional connectivity might be modulated by trait impulsivity. Then, we calculated the functional connectivity among these regions and the rest of the brain in order to assess if impulsivity trait altered their relationships. We found two DMN clusters located at the posterior cingulate cortex and the right angular gyrus which were negatively correlated with impulsivity scores. The whole-brain correlation analysis revealed the classic network of correlating and anti-correlating areas with respect to the DMN. The impulsivity trait modulated such pattern showing that the canonical anti-phasic relation between DMN and action-related network was reduced in high impulsive children. These results represent the first evidence that the impulsivity, measured as personality trait assessed through parents' report, exerts a modulatory influence over the functional connectivity of resting state brain networks in typically developing children. The present study goes further to connect developmental approaches, mainly based on data collected through the use of questionnaires, and behavioral neuroscience, interested in how differences in brain structure and functions reflect in differences in behavior.

  1. Altered regional connectivity reflecting effects of different anaesthesia protocols in the mouse brain. (United States)

    Wu, Tong; Grandjean, Joanes; Bosshard, Simone C; Rudin, Markus; Reutens, David; Jiang, Tianzi


    Studies in mice using resting-state functional magnetic resonance imaging (rs-fMRI) have provided opportunities to investigate the effects of pharmacological manipulations on brain function and map the phenotypes of mouse models of human brain disorders. Mouse rs-fMRI is typically performed under anaesthesia, which induces both regional suppression of brain activity and disruption of large-scale neural networks. Previous comparative studies using rodents investigating various drug effects on long-distance functional connectivity (FC) have reported agent-specific FC patterns, however, effects of regional suppression are sparsely explored. Here we examined changes in regional connectivity under six different anaesthesia conditions using mouse rs-fMRI with the goal of refining the framework of understanding the brain activation under anaesthesia at a local level. Regional homogeneity (ReHo) was used to map local synchronization in the brain, followed by analysis of several brain areas based on ReHo maps. The results revealed high local coherence in most brain areas. The primary somatosensory cortex and caudate-putamen showed agent-specific properties. Lower local coherence in the cingulate cortex was observed under medetomidine, particularly when compared to the combination of medetomidine and isoflurane. The thalamus was associated with retained local coherence across anaesthetic levels and multiple nuclei. These results show that anaesthesia induced by the investigated anaesthetics through different molecular targets promote agent-specific regional connectivity. In addition, ReHo is a data-driven method with minimum user interaction, easy to use and fast to compute. Given that examination of the brain at a local level is widely applied in human rs-fMRI studies, our results show its sensitivity to extract information on varied neuronal activity under six different regimens relevant to mouse functional imaging. These results, therefore, will inform future rs

  2. Hypothalamic digoxin, hemispheric chemical dominance, and peptic ulcer disease. (United States)

    Kurup, Ravi Kumar; Kurup, Parameswara Achutha


    The isoprenoid pathway produces three key metabolites--endogenous digoxin-like factor (EDLF) (membrane sodium-potassium ATPase inhibitor and regulator of neurotransmitter transport), ubiquinone (free radical scavenger), and dolichol (regulator of glycoconjugate metabolism). The pathway was assessed in peptic ulcer and acid peptic disease and its relation to hemispheric dominance studied. The activity of HMG CoA reductase, serum levels of EDLF, magnesium, tryptophan catabolites, and tyrosine catabolites were measured in acid peptic disease, right hemispheric dominant, left hemispheric dominant, and bihemispheric dominant individuals. All the patients with peptic ulcer disease were right-handed/left hemispheric dominant by the dichotic listening test. The pathway was upregulated with increased EDLF synthesis in peptic ulcer disease (PUD). There was increase in tryptophan catabolites and reduction in tyrosine catabolites in these patients. The ubiquinone levels were low and free radical production increased. Dolichol and glycoconjugate levels were increased and lysosomal stability reduced in patients with acid peptic disease (APD). There was increase in cholesterol:phospholipid ratio with decreased glyco conjugate levels in membranes of patients with PUD. Acid peptic disease represents an elevated EDLF state which can modulate gastric acid secretion and the structure of the gastric mucous barrier. It can also lead to persistence of Helicobacter pylori infection. The biochemical pattern obtained in peptic ulcer disease is similar to those obtained in left-handed/right hemispheric chemically dominant individuals. But all the patients with peptic ulcer disease were right-handed/left hemispheric dominant by the dichotic listen ing test. Hemispheric chemical dominance has no correlation with handedness or the dichotic listening test. Peptic ulcer disease occurs in right hemispheric chemically dominant individuals and is a reflection of altered brain function.

  3. Why size matters: differences in brain volume account for apparent sex differences in callosal anatomy: the sexual dimorphism of the corpus callosum. (United States)

    Luders, Eileen; Toga, Arthur W; Thompson, Paul M


    Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum.

  4. Compression of the North Hemisphere derived from space geodesy

    Institute of Scientific and Technical Information of China (English)

    金双根; 朱文耀


    The convergent and divergent velocities of active plate boundaries in the North Hemisphere are obtained with space geodetic data. The relative motions of adjacent plates in north-south direction are almost convergent; the spreading rates of the north mid-Atlantic ridge are smaller than the south mid-Atlantic ridge; the closed differences of the baseline length rates between stations on different plates along the latitudinal circle of 7.7(, 23.3o, 34.8o, 42.0o and 51.0o are all negative. All these show that the North Hemisphere is a compressive hemisphere.

  5. Gradient changes of bilateral cerebral hemisphere pressure in patients with lateral hemisphere injury%一侧大脑损伤患者两侧半球压力梯度的变化

    Institute of Scientific and Technical Information of China (English)

    姜启周; 裘五四; 方蓉; 徐海松


    Objective To investigate the gradient changes of bilateral cerebral hemisphere pressure after lateral hemisphere injury and observe their effects on craniotomy. Methods Twenty-four patients with cerebral contusion and subdural intracerebral hematoma were included in this study. All patients received brain parenehyma pressure (BPP) monitoring by introducing optic fibro sensor into each cerebral hemisphere via the frontal lobe. All patients underwent surgical craniotomy for evacuation of space occupying lesions such as cerebral hemisphere contusion, subdural and/or intracerebral hematoma.Preoperative and postoperative BPP data at different time points were recorded and analyzed. Results Preoperative BPP value of the injured hemispheres was significantly higher than that of the other hemisphere (P < 0. 01 ). There was no significant statistical difference upon BPP value at 0, 24 and 48 hours after operation between both hemispheres ( P > 0.05 ). The postoperative BPP value of bilateral hemispheres was lower than the preoperative one. Conclusions BPP monitoring sensors should be introduced into the injured hemisphere so that the valuable information can be timely showed. When the cerebral hemisphere has lesions after brain injury, such lesion becomes the source of elevated intracranial pressure and can result in bilateral hemisphere pressure gradient. Craniotomy can not only effectively lower the intracranial pressure, but also eliminate the BPP gradient, which contritbutes to reposition of the oppressed brain tissue.%目的 了解一侧大脑损伤后两侧半球压力梯度的变化及开颅手术的影响.方法 选择24例一侧大脑额、颞叶脑挫伤、硬膜下脑内血肿的患者,CT显示伤侧有占位效应、中线向对侧移位.入院后即分别于两侧额部钻颅置入光导纤维传感器行两侧大脑半球脑组织压(BPP)监护,所有患者都接受开颅血肿清除手术.分别于术前、术后收集两侧大脑

  6. Volumetric hemispheric ratio as a useful tool in personality psychology. (United States)

    Montag, Christian; Schoene-Bake, Jan-Christoph; Wagner, Jan; Reuter, Martin; Markett, Sebastian; Weber, Bernd; Quesada, Carlos M


    The present study investigates the link between volumetric hemispheric ratios (VHRs) and personality measures in N=267 healthy participants using Eysenck's Personality Inventory-Revised (EPQ-R) and the BIS/BAS scales. A robust association between extraversion and VHRs was observed for gray matter in males but not females. Higher gray matter volume in the left than in the right hemisphere was associated with higher extraversion in males. The results are discussed in the context of positive emotionality and laterality of the human brain.

  7. Adaptability of language-related brain network in a low-grade glioma patient

    Institute of Scientific and Technical Information of China (English)

    Olivera Sveljo; Katarina Koprivsek; Milos Lucic


    Because functional magnetic resonance imaging can be used for dynamic observation of functional cortical changes after brain injuries, we followed up functional magnetic resonance imaging manifestationsof a language-related brain network in a low -grade glioma patient. Disease progressionand therapy during a 3-year period were followed up at different time points: before and after reoperation,after radiation therapy, and 1 year after irradiation. During the whole 3-year follow -up period,the patient exhibited no neurological deficits while functional magnetic resonance imaging revealeddifferent topologies of the language-related brain network. During disease progression and after irradiation,the language-related brain network was extended or completely transferred to the nondominant(right) hemisphere. In addition, after reoperation and 1 year after irradiation, languageareas were primarily found in the language dominant (left) hemisphere. Our results suggest a highlevel of adaptability of the language-related cortical network of the bilateral hemispheres in thislow -grade glioma patient.

  8. Discrimination of different brain metastases and primary CNS lymphomas using morphologic criteria and diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bette, S.; Wiestler, B.; Huber, T.; Boeckh-Behrens, T.; Zimmer, C.; Kirschke, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuroradiology; Delbridge, C. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neuropathology; Meyer, B.; Gempt, J. [Technical University Munich, Klinikum rechts der Isar (Germany). Dept. of Neurosurgery


    Brain metastases are a common complication of cancer and occur in about 15-40% of patients with malignancies. The aim of this retrospective study was to differentiate between metastases from different primary tumors/CNS lymphyomas using morphologic criteria, fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Morphologic criteria such as hemorrhage, cysts, pattern of contrast enhancement and location were reported in 200 consecutive patients with brain metastases/primary CNS lymphomas. FA and ADC values were measured in regions of interest (ROIs) placed in the contrast-enhancing tumor part, the necrosis and the non-enhancing peritumoral region (NEPTR). Differences between histopathological subtypes of metastases were analyzed using non-parametric tests, decision trees and hierarchical clustering analysis. Significant differences were found in morphologic criteria such as hemorrhage or pattern of contrast enhancement. In diffusion measurements, significant differences between the different tumor entities were only found in ADC analyzed in the contrast-enhancing tumor part. Among single tumor entities, primary CNS lymphomas showed significantly lower median ADC values in the contrast-enhancing tumor part (ADC{sub lymphoma} 0.92 [0.83-1.07] vs. ADC{sub no} {sub lymphoma} 1.35 [1.10-1.64] P=0.001). Further differentiation between types of metastases was not possible using FA and ADC. There were morphologic differences among the main subtypes of brain metastases/CNS lymphomas. However, due to a high variability of common types of metastases and low specificity, prospective differentiation remained challenging. DTI including FA and ADC was not a reliable tool for differentiation between different histopathological subtypes of brain metastases except for CNS lymphomas showing lower ADC values. Biopsy, surgery and staging remain essential for diagnosis.

  9. Brain activity in advantageous and disadvantageous situations: implications for reward/punishment sensitivity in different situations.

    Directory of Open Access Journals (Sweden)

    Guangheng Dong

    Full Text Available OBJECTIVE: This study modeled win and lose trials in a simple gambling task to examine the effect of entire win-lose situations (WIN, LOSS, or TIE on single win/lose trials and related neural underpinnings. METHODS: The behavior responses and brain activities of 17 participants were recorded by an MRI scanner while they performed a gambling task. Different conditions were compared to determine the effect of the task on the behavior and brain activity of the participants. Correlations between brain activity and behavior were calculated to support the imaging results. RESULTS: In win trials, LOSS caused less intense posterior cingulate activity than TIE. In lose trials, LOSS caused more intense activity in the right superior temporal gyrus, bilateral superior frontal gyrus, bilateral anterior cingulate, bilateral insula cortex, and left orbitofrontal cortex than WIN and TIE. CONCLUSIONS: The experiences of the participants in win trials showed great similarity among different win-lose situations. However, the brain activity and behavior responses of the participants in lose trials indicated that they experienced stronger negative emotion in LOSS. The participants also showed an increased desire to win in LOSS than in WIN or TIE conditions.

  10. The effects of different hyperbaric oxygen manipulations in rats after traumatic brain injury. (United States)

    Yang, Yang; Zhang, Yong-Gang; Lin, Guo-An; Xie, He-Qiu; Pan, Hai-Tao; Huang, Ben-Qing; Liu, Ji-Dong; Liu, Hui; Zhang, Nan; Li, Li; Chen, Jian-Hua


    The protective effects of hyperbaric oxygenation following traumatic brain injury have been widely investigated; however, few studies have made systematic comparisons between the different hyperbaric oxygenation manipulations and their corresponding effects. In this study, male Sprague-Dawley rats were observed at 4h, 15d and 75d after traumatic brain injury. The effects of the different hyperbaric oxygenation manipulations on the rats were compared based on morphological, molecular biological and behavioral tests. Our results showed that hyperbaric oxygenation inhibited cell apoptosis in the rat hippocampus and improved their physiological functions. The effects observed in the hyperbaric oxygen-early group were better than the hyperbaric oxygen-delayed group, and the hyperbaric oxygen-early-delayed group demonstrated the best effects among all the groups. Our results showed the hyperbaric oxygenation was recommended early and delayed post-traumatic brain injury and exposure to hyperbaric oxygenation should be prolonged. These findings provide new ideal therapeutic insight for the clinical treatment of traumatic brain injury.

  11. Western Hemisphere Knowledge Partnerships (United States)

    Malone, T. F.


    , and application of knowledge concerning the nature of -- and interaction among -- matter, living organisms, energy, information, and human behavior. This strategy calls for innovative partnerships among the physical, biological, health, and social sciences, engineering, and the humanities. New kinds of partnership must also be forged among academia, business and industry, governments, and nongovernmental organizations. Geophysicists can play an important role in these partnerships. A focus for these partnerships is to manage the individual economic productivity that drives both human development and global change. As world population approaches stability during the twenty-first century, individual economic productivity will be the critical link between the human and the natural systems on planet Earth. AGU is among a core group of individuals and institutions proposing Western Hemisphere Knowledge Partnerships (WHKP) to test the hypothesis that knowledge, broadly construed, is an important organizing principle in choosing a path into the future. The WHKP agenda includes: (1) life-long learning, (2) the health and resilience of natural ecosystems, (3) eco-efficiency in economic production and consumption, (4) extension of national income accounts, (5) environmentally benign sources of energy, (6) delivery of health care, (7) intellectual property rights, and (8) networks for action by local communities.Collaboratories and distance education technologies will be major tools. A panel of experts will explore this proposal.

  12. Different brain circuits underlie motor and perceptual representations of temporal intervals

    DEFF Research Database (Denmark)

    Bueti, Doemnica; Walsh, Vincent; Frith, Christopher


    conditions, we explored commonalities and differences in brain areas involved in reproduction and estimation of temporal intervals. The basal ganglia and the cerebellum were commonly active in both temporal tasks, consistent with suggestions that perception and production of time are subserved by the same......In everyday life, temporal information is used for both perception and action, but whether these two functions reflect the operation of similar or different neural circuits is unclear. We used functional magnetic resonance imaging to investigate the neural correlates of processing temporal...... information when either a motor or a perceptual representation is used. Participants viewed two identical sequences of visual stimuli and used the information differently to perform either a temporal reproduction or a temporal estimation task. By comparing brain activity evoked by these tasks and control...

  13. The DNA methylome and transcriptome of different brain regions in schizophrenia and bipolar disorder.

    Directory of Open Access Journals (Sweden)

    Yun Xiao

    Full Text Available Extensive changes in DNA methylation have been observed in schizophrenia (SC and bipolar disorder (BP, and may contribute to the pathogenesis of these disorders. Here, we performed genome-scale DNA methylation profiling using methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq on two brain regions (including frontal cortex and anterior cingulate in 5 SC, 7 BP and 6 normal subjects. Comparing with normal controls, we identified substantial differentially methylated regions (DMRs in these two brain regions of SC and BP. To our surprise, different brain regions show completely distinct distributions of DMRs across the genomes. In frontal cortex of both SC and BP subjects, we observed widespread hypomethylation as compared to normal controls, preferentially targeting the terminal ends of the chromosomes. In contrast, in anterior cingulate, both SC and BP subjects displayed extensive gain of methylation. Notably, in these two brain regions of SC and BP, only a few DMRs overlapped with promoters, whereas a greater proportion occurs in introns and intergenic regions. Functional enrichment analysis indicated that important psychiatric disorder-related biological processes such as neuron development, differentiation and projection may be altered by epigenetic changes located in the intronic regions. Transcriptome analysis revealed consistent dysfunctional processes with those determined by DMRs. Furthermore, DMRs in the same brain regions from SC and BP could successfully distinguish BP and/or SC from normal controls while differentially expressed genes could not. Overall, our results support a major role for brain-region-dependent aberrant DNA methylation in the pathogenesis of these two disorders.

  14. Corticospinal state variability and hemispheric asymmetries in motivational tendencies

    NARCIS (Netherlands)

    Schutter, D.J.L.G.; Hofman, D.; Hoppenbrouwers, S.S.; Kenemans, J.L.


    This transcranial magnetic stimulation (TMS) study examined interrelations between asymmetrical hemispheric differences in the degree of variability of corticospinal excitability levels and motivational tendencies. The relative standard deviation in motor evoked potentials (MEP) to single pulse TMS

  15. Optical vortex beam transmission with different OAM in scattering beads and brain tissue media (United States)

    Wang, W. B.; Shi, Lingyan; Lindwasser, Lukas; Marque, Paulo; Lavery, M. P. J.; Alfano, R. R.


    Light transmission of Laguerre Gaussian (LG) vortex beams with different orbital angular momentum (OAM) values (L) in scattering beads and mouse brain tissue media were experimentally investigated for the first time in comparison with Gaussian (G) beams. The LG beams with different OAM were generated using a spatial light modulator (SLM) in reflection mode. The scattering beads media consist of various sizes and concentrations of latex beads in water solutions. The transmissions of LG and G beams through scattering beads and brain tissue media were measured with different ratios of sample thicknesses (z) to scattering mean free path (ls) of the turbid media, z/ls. The results indicate that within the ballistic region where z/ls is small, the LG and G beams show no significant difference, while in the diffusive region where z/ls is higher, the vortex beams show higher transmission than G beams. In the diffusive region, the LG beams with higher L values show higher transmission than the beams with lower L values due to the eigen channels in the media. The transition points from the ballistic to diffusive regions for different scattering beads and brain tissue media were studied.

  16. Scrapie strains retain their distinctive characteristics following passages of homogenates from different brain regions and spleen. (United States)

    Carp, R I; Meeker, H; Sersen, E


    The molecular basis of differences among scrapie strains is unknown. The prion theory posits that there are differences in the conformation of the host protease-resistant protein (PrP) molecules and that these differences are responsible for scrapie strains. A corollary of this theory is that the origin of host PrP variation resides in different neuronal cell types. To assess this concept, preparations from three brain regions (cerebrum, cerebellum and olfactory bulb) and from spleen were passaged in C57BL mice by intracerebral injection. After three passages of three scrapie strains in this manner, homogenates of each brain region and spleen were tested for several of the characteristics that distinguish the three strains: (1) the rank order of incubation periods in C57BL mice, (2) induction of obesity in SJL mice and (3) comparative incubation periods in mice with three genotypes for the scrapie incubation period marker. Analysis revealed that virtually all of the criteria that distinguished the three strains prior to passages of the three brain regions and spleen were retained after this series of passages. This finding argues against cellular-based PrP differences providing a basis for strain specificity.

  17. Prognostic implications of total hemispheric glucose metabolism ratio in cerebro-cerebellar diaschisis

    DEFF Research Database (Denmark)

    Segtnan, Eivind Antonsen; Grupe, Peter; Jarden, Jens Ole


    PURPOSE: Diaschisis denotes brain dysfunction remote from a focal brain lesion. We have quantified diaschisis and investigated its prognostic value in glioma. METHODS AND MATERIAL: We compared 50 (18)F-FDG-PET-CT studies collected prospectively from 14 patients with supratentorial glioma (5 men...... and 9 women aged 35-77 years) with 10 single scans from healthy controls aged 43-75 years. Dedicated 3D-segmentation software was used to obtain total hemispheric glucose metabolic ratios (THGr) by dividing total hemispheric (18)F-fluorodeoxyglucose (FDG) uptake in each diaschitic hemisphere, i.......e., the ipsilateral cerebral hemisphere (THGr(Ce)) and the contralateral cerebellar hemisphere (THGr(Cb)), to its respective contralateral side. Receiver operating characteristic (ROC) analysis was performed to determine optimal cut-offs for combinations of THGr(Ce) and THGr(Cb). Two independent observers obtained...

  18. Evidence of hemispheric specialization in marmosets (Callithrix penicillata using tympanic membrane thermometry

    Directory of Open Access Journals (Sweden)

    C. Tomaz


    Full Text Available Recent studies have employed tympanic thermometry to assess lateralization of cognitive and emotional functions in primates. However, no studies using this technique have investigated the possibility of hemispheric specialization in New World monkeys. Therefore, the aim of the present study was to investigate tympanic membrane (TM temperature asymmetries and their possible correlation with stress responses in marmosets (Callithrix penicillata. Infrared TM thermometry was completed bilaterally in 24 animals (14 males and 10 females during a stressful situation of capture and restraint. There were no significant differences between gender. A significant negative correlation was observed between TM temperature of the right ear and the number of captures (r = -0.633; P<0.001. Subjects with a more frequent previous history of captures (5 to 9 captures; N = 11 showed lower TM temperature when compared to those with fewer previous captures (1 to 4 captures; N = 13. No differences were observed for the left TM temperature. These results suggest that under intense emotional challenge (capture and restraint there is a stronger activation of the neural structures situated in the right brain hemisphere. Taken together, the data reveal for the first time evidence of hemispheric specialization in emotional physiological processing in a New World monkey.

  19. Differences in brain activation between tremor- and nontremor-dominant Parkinson disease. (United States)

    Prodoehl, Janey; Planetta, Peggy J; Kurani, Ajay S; Comella, Cynthia L; Corcos, Daniel M; Vaillancourt, David E


    OBJECTIVE To compare differences in functional brain activity between tremor- and nontremor-dominant subtypes of Parkinson disease (PD) using functional magnetic resonance imaging. DESIGN In our study, patients with tremor-dominant PD and those with nontremor-dominant PD performed a grip task, and the results obtained were compared using voxelwise analysis. Areas of the brain that were significantly different were then examined using a region-of-interest analysis to compare these patients with healthy controls. Voxel-based morphometry was used to determine macroscopic differences in gray and white matter volume between patient groups. SETTING University-affiliated research institution. PARTICIPANTS A total of 20 drug-naive patients with PD (10 with tremor-dominant PD and 10 with nontremor-dominant PD) and a total of 20 healthy controls. MAIN OUTCOME MEASURES Blood oxygenation level-dependent activation and percent signal change. RESULTS Robust findings across both voxelwise and region-of-interest analyses showed that, compared with patients with tremor-dominant PD, patients with nontremor-dominant PD had reduced activation in the ipsilateral dorsolateral prefrontal cortex, the globus pallidus interna, and the globus pallidus externa. Region-of-interest analyses confirmed that patients with nontremor-dominant PD had reduced activity in the ipsilateral dorsolateral prefrontal cortex, the globus pallidus interna, and the globus pallidus externa compared with patients with tremor-dominant PD and healthy controls. Patients with tremor-dominant PD had increased activity in the contralateral dorsolateral prefrontal cortex compared with patients with nontremor-dominant PD and healthy controls. These results could not be explained by differences in gray or white matter volume. CONCLUSIONS Reduced brain activity occurs in the prefrontal cortex and globus pallidus of patients with nontremor-dominant PD compared with both patients with tremor-dominant PD and healthy controls

  20. Detection of electroporation-induced membrane permeabilization states in the brain using diffusion-weighted MRI

    DEFF Research Database (Denmark)

    Mahmood, Faisal; Hansen, Rasmus H; Agerholm-Larsen, Birgit


    (DW-MRI) as a quantitative method for detecting EP-induced membrane permeabilization of brain tissue using a rat brain model. MATERIAL AND METHODS: Fifty-four anesthetized Sprague-Dawley male rats were electroporated in the right hemisphere, using different voltage levels to induce no permeabilization......-induced permeabilization of brain tissue and to some extent of differentiating NP, TMP and PMP using appropriate scan timing....

  1. East-West differences in perception of brain death. Review of history, current understandings, and directions for future research. (United States)

    Yang, Qing; Miller, Geoffrey


    The concept of brain death as equivalent to cardiopulmonary death was initially conceived following developments in neuroscience, critical care, and transplant technology. It is now a routine part of medicine in Western countries, including the United States. In contrast, Eastern countries have been reluctant to incorporate brain death into legislation and medical practice. Several countries, most notably China, still lack laws recognizing brain death and national medical standards for making the diagnosis. The perception is that Asians are less likely to approve of brain death or organ transplant from brain dead donors. Cultural and religious traditions have been referenced to explain this apparent difference. In the West, the status of the brain as home to the soul in Enlightenment philosophy, combined with pragmatism and utilitarianism, supports the concept of brain death. In the East, the integration of body with spirit and nature in Buddhist and folk beliefs, along with the Confucian social structure that builds upon interpersonal relationships, argues against brain death. However, it is unclear whether these reasoning strategies are explicitly used when families and medical providers are faced with acknowledging brain death. Their decisions are more likely to involve a prioritization of values and a rationalization of intuitive responses. Why and whether there might be differences between East and West in the acceptance of the brain death concept requires further empirical testing, which would help inform policy-making and facilitate communication between providers and patients from different cultural and ethnic backgrounds.

  2. Caffeine improves left hemisphere processing of positive words.

    Directory of Open Access Journals (Sweden)

    Lars Kuchinke

    Full Text Available A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

  3. Age-Related Differences in the Brain Areas outside the Classical Language Areas among Adults Using Category Decision Task (United States)

    Cho, Yong Won; Song, Hui-Jin; Lee, Jae Jun; Lee, Joo Hwa; Lee, Hui Joong; Yi, Sang Doe; Chang, Hyuk Won; Berl, Madison M.; Gaillard, William D.; Chang, Yongmin


    Older adults perform much like younger adults on language. This similar level of performance, however, may come about through different underlying brain processes. In the present study, we evaluated age-related differences in the brain areas outside the typical language areas among adults using a category decision task. Our results showed that…

  4. Regional Differences in Brain Volume Predict the Acquisition of Skill in a Complex Real-Time Strategy Videogame (United States)

    Basak, Chandramallika; Voss, Michelle W.; Erickson, Kirk I.; Boot, Walter R.; Kramer, Arthur F.


    Previous studies have found that differences in brain volume among older adults predict performance in laboratory tasks of executive control, memory, and motor learning. In the present study we asked whether regional differences in brain volume as assessed by the application of a voxel-based morphometry technique on high resolution MRI would also…

  5. Doses delivered to normal brain under different treatment protocols at Brookhaven National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Capala, J.; Coderre, J.A.; Liu, H.B. [and others


    As of October 31, 1996, 23 glioblastoma multiforme patients underwent BNCT under several treatment protocols at the Brookhaven Medical Research Reactor. For treatment planning and dosimetry purposes, these protocols may be divided into four groups. The first group comprises protocols that used an 8-cm collimator and allowed a peak normal brain dose of 10.5 Gy-Eq to avolume of 1 cm{sup 3} were the thermal neutron flux was maximal (even if it happened to be in the tumor volume). The second group differs from the first in that it allowed a peak normal brain dose of 12.6 Gy-Eq. The protocols of the third and fourth groups allowed the prescribed peak normal brain dose of 12.6 Gy-Eq to be outside of the tumor volume, used a 12-cm collimator and, respectively, uni- or bilateral irradiations. We describe the treatment planning procedures and report the doses delivered to various structures of the brain.

  6. Inhibition of acetylcholinesterase and different ATPases by a novel phosphorothionate (RPR-II) in rat brain. (United States)

    Rahman, M F; Siddiqui, M K; Jamil, K


    A novel phosphorothionate (2-butenoic acid-3-(diethoxy phosphinothioyl)-methyl ester (RPR-II), synthesized at the Indian Institute of Chemical Technology, Hyderabad, targets its effect on rat brain acetylcholinesterase (AChE) and Na(+)-K(+), Mg(2+), and Ca(2+) ATPases, as evident in this investigation. Three subchronic doses 0.014 (low), 0.028 (medium), and 0.042 (high) mg kg(-1) were administered to rats daily for a period of 90 days RPR-II caused statistically significant dose- and time-dependent inhibition in brain AChE and also in Na(+)-K(+), Mg(2+), and Ca(2+) ATPases in both male and female rats after 45 and 90 days of treatment. The low dose was generally insignificant while the medium and high doses were significantly effective. Females were more susceptible than males with regard to brain AChE, Na(+)-K(+), and Mg(2+) ATPases, which indicates sexual dimorphism in the treated rats. Interestingly, after 28 days post-treatment, recovery of these enzymes was observed. The relative sensitivities of these enzymes indicated that brain AChE was more sensitive than any of the ATPases, but among the ATPases Na(+)-K(+) ATPase was more susceptible than Ca(2+) or Mg(2+) ATPases. This compound, besides inhibiting the target of organophosphates, AChE, also inhibited different ATPases, suggesting both synaptic transmission and nerve conduction were affected.

  7. Targeting different pathophysiological events after traumatic brain injury in mice: Role of melatonin and memantine. (United States)

    Kelestemur, Taha; Yulug, Burak; Caglayan, Ahmet Burak; Beker, Mustafa Caglar; Kilic, Ulkan; Caglayan, Berrak; Yalcin, Esra; Gundogdu, Reyhan Zeynep; Kilic, Ertugrul


    The tissue damage that emerges during traumatic brain injury (TBI) is a consequence of a variety of pathophysiological events, including free radical generation and over-activation of N-methyl-d-aspartate-type glutamate receptors (NMDAR). Considering the complex pathophysiology of TBI, we hypothesized that combination of neuroprotective compounds, targeting different events which appear during injury, may be a more promising approach for patients. In this context, both NMDAR antagonist memantine and free radical scavenger melatonin are safe in humans and promising agents for the treatment of TBI. Herein, we examined the effects of melatonin administered alone or in combination with memantine on the activation of signaling pathways, injury development and DNA fragmentation. Both compounds reduced brain injury moderately and the density of DNA fragmentation significantly. Notably, melatonin/memantine combination decreased brain injury and DNA fragmentation significantly, which was associated with reduced p38 and ERK-1/2 phosphorylation. As compared with melatonin and memantine groups, SAPK/JNK-1/2 phosphorylation was also reduced in melatonin/memantine combined animals. In addition, melatonin, memantine and their combination decreased iNOS activity significantly. Here, we provide evidence that melatonin/memantine combination protects brain from traumatic injury, which was associated with decreased DNA fragmentation, p38 phosphorylation and iNOS activity.

  8. Effects of different fixatives on the TrkB-immunoreactivity in rat brain

    Institute of Scientific and Technical Information of China (English)

    张富兴; 黎振航; 李金莲; 岑国欣; 陈应城


    Objective: To find out an effective fixative in immunohistochemistry for high-affinity neurotrophin receptor-tyrosine kinase (Trk) B. Methods: Comparing the results from four groups of adult rats which were fixed by different fixatives before the brain sections were processed for TrkB immunohistochemistry. Results: In the four groups, TrkB immunoreactive cells were observed throughout the whole brain, but the intensity of immunoreactive cells and the background staining exhibited a marked difference among the groups. Conclusion: Using 0.3%-0.5% paraformaldehyde in 75% saturated picric acid 0.1 mol/L di-sodium hydrogen phosphate buffer as the fixative may yield the best quality of TrkB immunoreactivity.

  9. Determination of hemispheric emotional valence in individual subjects: A new approach with research and therapeutic implications

    Directory of Open Access Journals (Sweden)

    Polcari Ann


    Full Text Available Abstract Background Much has been theorized about the emotional properties of the hemispheres. Our review of the dominant hypotheses put forth by Schore, Joseph, Davidson, and Harmon-Jones on hemispheric emotional valences (HEV shows that none are supported by robust data. Instead, we propose that individual's hemispheres are organized to have differing HEVs that can be lateralized in either direction. Methods Probe auditory evoked potentials (AEP recorded during a neutral and an upsetting memory were used to assess HEV in 28 (20 F right-handed subjects who were either victims of childhood maltreatment (N = 12 or healthy controls. In a sub-population, we determined HEV by emotional response to lateral visual field stimulation (LVFS, in which vision is limited to one, then the other hemifield. We compare a number of morphometric and functional brain measures between individuals who have right-negative versus left-negative HEV. Results Using AEPs to determine HEV, we found 62% of controls and 67% of maltreated subjects had right negative HEV. There was a strong interaction between HEV-laterality and gender, which together accounted for 60% of individual variability in total grey matter volume (GMV. HEV-laterality was associated with differences in hippocampal volume, amygdala/hippocampal ratios, and measures of verbal, visual and global memory. HEV-laterality was associated also with different constellations of symptoms comparing maltreated subjects to controls. Emotional response to LVFS provided a convenient and complementary measure of HEV-laterality that correlated significantly with the HEVs determined by AEPs. Conclusion Our findings suggest that HEV-laterality, like handedness or gender, is an important individual difference with significant implications for brain and behavioral research, and for guiding lateralized treatments such as rTMS.

  10. Associations between insulin action and integrity of brain microstructure differ with familial longevity and with age

    Directory of Open Access Journals (Sweden)

    Abimbola A. Akintola


    Full Text Available Impaired glucose metabolism and type 2 diabetes have been associated with cognitive decline, dementia, and with structural and functional brain features. However, it is unclear whether these associations differ in individuals that differ in familial longevity or age. Here, we investigated the association between parameters of glucose metabolism and microstructural brain integrity in offspring of long-lived families (offspring and controls; and age categories thereof. From the Leiden Longevity Study, 132 participants underwent oral glucose tolerance test to assess glycemia (fasted glucose and glucose area-under-the-curve (AUC, insulin resistance (fasted insulin, AUCinsulin, and homeostatic model assessment of insulin resistance (HOMA-IR, and pancreatic Beta cell secretory capacity (insulinogenic index. 3Tesla MRI and Magnetization Transfer (MT imaging MT-ratio peak-height was used to quantify differences in microstructural brain parenchymal tissue homogeneity that remain invisible on conventional MRI. Analyses were performed in offspring and age-matched controls, with and without stratification for age.In the full offspring group only, reduced peak-height in grey and white matter was inversely associated with AUCinsulin, fasted insulin, HOMA-IR and insulinogenic-index (all p65 years: in younger controls, significantly stronger inverse associations were observed between peak-height and fasted glucose, AUCglucose, fasted insulin, AUCinsulin and HOMA-IR in grey matter; and for AUCglucose, fasted insulin and HOMA-IR in white matter (all P-interaction<0.05. Although the strength of the associations tended to attenuate with age in the offspring group, the difference between age groups was not statistically significant. Thus, associations between impaired insulin action and reduced microstructural brain parenchymal tissue homogeneity were stronger in offspring compared to controls, and seemed to diminish with age.

  11. Trajectories of brain aging in middle-aged and older adults: regional and individual differences. (United States)

    Raz, Naftali; Ghisletta, Paolo; Rodrigue, Karen M; Kennedy, Kristen M; Lindenberger, Ulman


    The human brain changes with age. However, the rate and the trajectories of change vary among the brain regions and among individuals, and the reasons for these differences are unclear. In a sample of healthy middle-aged and older adults, we examined mean volume change and individual differences in the rate of change in 12 regional brain volumes over approximately 30 months. In addition to the baseline assessment, there were two follow-ups, 15 months apart. We observed significant average shrinkage of the hippocampus, entorhinal cortex, orbital-frontal cortex, and cerebellum in each of the intervals. Shrinkage of the hippocampus accelerated with time, whereas shrinkage of the caudate nucleus, prefrontal subcortical white matter, and corpus callosum emerged only at the second follow-up. Throughout both assessment intervals, the mean volumes of the lateral prefrontal and primary visual cortices, putamen, and pons did not change. Significant individual differences in shrinkage rates were observed in the lateral prefrontal cortex, the cerebellum, and all the white matter regions throughout the study, whereas additional regions (medial-temporal structures, the insula, and the basal ganglia) showed significant individual variation in change during the second follow-up. No individual variability was noted in the change of orbital frontal and visual cortices. In two white matter regions, we were able to identify factors associated with individual differences in brain shrinkage. In corpus callosum, shrinkage rate was greater in persons with hypertension, and in the pons, women and carriers of the ApoEepsilon4 allele exhibited declines not noted in the whole sample.

  12. Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

    Directory of Open Access Journals (Sweden)

    Caroline Clouard

    Full Text Available This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d. infusions of 15% glucose (F(Glu, lithium chloride (F(LiCl, or saline (control treatment, F(NaCl. One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl than the F(NaCl or F(Glu meals. During the two-choice tests performed one and five weeks later, the F(NaCl and F(Glu foods were significantly preferred over the F(LICl food even in the absence of i.d. infusions. Surprisingly, the F(NaCl food was also preferred over the F(Glu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

  13. Handedness is related to neural mechanisms underlying hemispheric lateralization of face processing (United States)

    Frässle, Stefan; Krach, Sören; Paulus, Frieder Michel; Jansen, Andreas


    While the right-hemispheric lateralization of the face perception network is well established, recent evidence suggests that handedness affects the cerebral lateralization of face processing at the hierarchical level of the fusiform face area (FFA). However, the neural mechanisms underlying differential hemispheric lateralization of face perception in right- and left-handers are largely unknown. Using dynamic causal modeling (DCM) for fMRI, we aimed to unravel the putative processes that mediate handedness-related differences by investigating the effective connectivity in the bilateral core face perception network. Our results reveal an enhanced recruitment of the left FFA in left-handers compared to right-handers, as evidenced by more pronounced face-specific modulatory influences on both intra- and interhemispheric connections. As structural and physiological correlates of handedness-related differences in face processing, right- and left-handers varied with regard to their gray matter volume in the left fusiform gyrus and their pupil responses to face stimuli. Overall, these results describe how handedness is related to the lateralization of the core face perception network, and point to different neural mechanisms underlying face processing in right- and left-handers. In a wider context, this demonstrates the entanglement of structurally and functionally remote brain networks, suggesting a broader underlying process regulating brain lateralization.

  14. Effect of manganese on the concentration of amino acids in different regions of the rat brain. (United States)

    Lipe, G W; Duhart, H; Newport, G D; Slikker, W; Ali, S F


    The present study was designed to determine if chronic exposure of weanlings and adult rats to Mn produces significant alterations in amino acid concentrations in different regions of the rat brain. Weanling (30 day old) and adult (90 day old) male rats were exposed to 10 and 20 mg Mn/kg body weight per day, by gavage, for 30 days. Forty-eight hours after the last dose, animals were sacrificed by decapitation and brains were dissected into different regions to determine the concentration of amino acids by HPLC/EC. A dose dependent decrease in body weight gain was found in the adult, but not in the weanling rats. Significant increases occurred in concentrations of aspartate, glutamate, glutamine, taurine and gamma-aminobutyric acid (GABA) in the cerebellum of the adult rats dosed with 20 mg/kg per day, Mn. A significant decrease in the concentration of glutamine was observed in caudate nucleus and hippocampus of weanling rats dosed with 10 mg/kg, Mn. These data suggest that chronic Mn exposure can produce a decrease in body weight gain in adult rats and alterations in amino acids in different regions of weanling and adult rat brains.

  15. Evaluating fMRI methods for assessing hemispheric language dominance in healthy subjects

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    Baciu, Monica [Laboratoire de Psychologie et NeuroCognition, UMR 5105 CNRS, Universite Pierre Mendes-France, F38040 Grenoble Cedex 09 (France)]. E-mail:; Juphard, Alexandra [Laboratoire de Psychologie et NeuroCognition, UMR 5105 CNRS, Universite Pierre Mendes-France, F38040 Grenoble Cedex 09 (France); Cousin, Emilie [Laboratoire de Psychologie et NeuroCognition, UMR 5105 CNRS, Universite Pierre Mendes-France, F38040 Grenoble Cedex 09 (France); Bas, Jean Francois Le [Unite IRM, CHU Grenoble (France)


    We evaluated two methods for quantifying the hemispheric language dominance in healthy subjects, by using a rhyme detection (deciding whether couple of words rhyme) and a word fluency (generating words starting with a given letter) task. One of methods called 'flip method' (FM) was based on the direct statistical comparison between hemispheres' activity. The second one, the classical lateralization indices method (LIM), was based on calculating lateralization indices by taking into account the number of activated pixels within hemispheres. The main difference between methods is the statistical assessment of the inter-hemispheric difference: while FM shows if the difference between hemispheres' activity is statistically significant, LIM shows only that if there is a difference between hemispheres. The robustness of LIM and FM was assessed by calculating correlation coefficients between LIs obtained with each of these methods and manual lateralization indices MLI obtained with Edinburgh inventory. Our results showed significant correlation between LIs provided by each method and the MIL, suggesting that both methods are robust for quantifying hemispheric dominance for language in healthy subjects. In the present study we also evaluated the effect of spatial normalization, smoothing and 'clustering' (NSC) on the intra-hemispheric location of activated regions and inter-hemispheric asymmetry of the activation. Our results have shown that NSC did not affect the hemispheric specialization but increased the value of the inter-hemispheric difference.

  16. Preliminary Study of Brain Glucose Metabolism Changes in Patients with Lung Cancer of Different Histological Types

    Institute of Scientific and Technical Information of China (English)

    Wei-Ling Li; Chang Fu; Ang Xuan; Da-Peng Shi; Yong-Ju Gao; Jie Zhang; Jun-Ling Xu


    Background:Cerebral glucose metabolism changes are always observed in patients suffering from malignant tumors.This preliminary study aimed to investigate the brain glucose metabolism changes in patients with lung cancer of different histological types.Methods:One hundred and twenty patients with primary untreated lung cancer,who visited People's Hospital of Zhengzhou University from February 2012 to July 2013,were divided into three groups based on histological types confirmed by biopsy or surgical pathology,which included adenocarcinoma (52 cases),squamous cell carcinoma (43 cases),and small-cell carcinoma (25 cases).The whole body 18F-fluorodeoxyglucose (1 8F-FDG) positron emission tomography (PET)/computed tomography (CT) of these cases was retrospectively studied.The brain PET data of three groups were analyzed individually using statistical parametric maps (SPM) software,with 50 age-matched and gender-matched healthy controls for comparison.Results:The brain resting glucose metabolism in all three lung cancer groups showed regional cerebral metabolic reduction.The hypo-metabolic cerebral regions were mainly distributed at the left superior and middle frontal,bilateral superior and middle temporal and inferior and middle temporal gyrus.Besides,the hypo-metabolic regions were also found in the right inferior parietal lobule and hippocampus in the small-cell carcinoma group.The area of the total hypo-metabolic cerebral regions in the small-cell carcinoma group (total voxel value 3255) was larger than those in the adenocarcinoma group (total voxel value 1217) and squamous cell carcinoma group (total voxel value 1292).Conclusions:The brain resting glucose metabolism in patients with lung cancer shows regional cerebral metabolic reduction and the brain hypo-metabolic changes are related to the histological types of lung cancer.

  17. Metabolic enhancer piracetam attenuates rotenone induced oxidative stress: a study in different rat brain regions. (United States)

    Verma, Dinesh Kumar; Joshi, Neeraj; Raju, Kunumuri Sivarama; Wahajuddin, Muhammad; Singh, Rama Kant; Singh, Sarika


    Piracetam is clinically being used nootropic drug but the details of its neuroprotective mechanism are not well studied. The present study was conducted to assess the effects of piracetam on rotenone induced oxidative stress by using both ex vivo and in vivo test systems. Rats were treated with piracetam (600 mg/kg b.w. oral) for seven constitutive days prior to rotenone administration (intracerebroventricular, 12 µg) in rat brain. Rotenone induced oxidative stress was assessed after 1 h and 24 h of rotenone administration. Ex vivo estimations were performed by using two experimental designs. In one experimental design the rat brain homogenate was treated with rotenone (1 mM, 2 mM and 4 mM) and rotenone+piracetam (10 mM) for 1 h. While in second experimental design the rats were pretreated with piracetam for seven consecutive days. On eighth day the rats were sacrificed, brain homogenate was prepared and treated with rotenone (1 mM, 2 mM and 4mM) for 1h. After treatment the glutathione (GSH) and malondialdehyde (MDA) levels were estimated in brain homogenate. In vivo study showed that pretreatment of piracetam offered significant protection against rotenone induced decreased GSH and increased MDA level though the protection was region specific. But the co-treatment of piracetam with rotenone did not offer significant protection against rotenone induced oxidative stress in ex vivo study. Whereas ex vivo experiments in rat brain homogenate of piracetam pretreated rats, showed the significant protection against rotenone induced oxidative stress. Findings indicated that pretreatment of piracetam significantly attenuated the rotenone induced oxidative stress though the protection was region specific. Piracetam treatment to rats led to its absorption and accumulation in different brain regions as assessed by liquid chromatography mass spectrometry/mass spectrometry. In conclusion, study indicates the piracetam is able to enhance the antioxidant capacity in brain cells


    Directory of Open Access Journals (Sweden)

    Rebeca Diez-Alarcia


    Full Text Available Cannabinoid receptors are able to couple to different families of G-proteins when activated by an agonist drug. It has been suggested that different intracellular responses may be activated depending on the ligand. The goal of the present study was to characterize the pattern of G protein subunit stimulation triggered by three different cannabinoid ligands, THC, WIN55212-2 and ACEA in mouse brain cortex.Stimulation of the [35S]GTPS binding coupled to specific immunoprecipitation with antibodies against different subtypes of G proteins (Gαi1, Gαi2, Gαi3, Gαo, Gαz, Gαs, Gαq/11, and Gα12/13, in the presence of Δ9-THC, WIN55212-2 and ACEA (submaximal concentration 10 µM was determined by Scintillation Proximity Assay (SPA technique in mouse cortex of wild type, CB1 knock-out, CB2 knock-out and CB1/CB2 double knock-out mice. Results show that, in mouse brain cortex, cannabinoid agonists are able to significantly stimulate not only the classical inhibitory Gαi/o subunits but also other G subunits like Gαz, Gαq/11, and Gα12/13. Moreover, the specific pattern of G protein subunit activation is different depending on the ligand. In conclusion, our results demonstrate that, in mice brain native tissue, different exogenous cannabinoid ligands are able to selectively activate different inhibitory and non-inhibitory Gα protein subtypes, through the activation of CB1 and/or CB2 receptors. Results of the present study may help to understand the specific molecular pathways involved in the pharmacological effects of cannabinoid-derived drugs.

  19. Biased Agonism of Three Different Cannabinoid Receptor Agonists in Mouse Brain Cortex (United States)

    Diez-Alarcia, Rebeca; Ibarra-Lecue, Inés; Lopez-Cardona, Ángela P.; Meana, Javier; Gutierrez-Adán, Alfonso; Callado, Luis F.; Agirregoitia, Ekaitz; Urigüen, Leyre


    Cannabinoid receptors are able to couple to different families of G proteins when activated by an agonist drug. It has been suggested that different intracellular responses may be activated depending on the ligand. The goal of the present study was to characterize the pattern of G protein subunit stimulation triggered by three different cannabinoid ligands, Δ9-THC, WIN55212-2, and ACEA in mouse brain cortex. Stimulation of the [35S]GTPγS binding coupled to specific immunoprecipitation with antibodies against different subtypes of G proteins (Gαi1, Gαi2, Gαi3, Gαo, Gαz, Gαs, Gαq/11, and Gα12/13), in the presence of Δ9-THC, WIN55212-2 and ACEA (submaximal concentration 10 μM) was determined by scintillation proximity assay (SPA) technique in mouse cortex of wild type, CB1 knock-out, CB2 knock-out and CB1/CB2 double knock-out mice. Results show that, in mouse brain cortex, cannabinoid agonists are able to significantly stimulate not only the classical inhibitory Gαi/o subunits but also other G subunits like Gαz, Gαq/11, and Gα12/13. Moreover, the specific pattern of G protein subunit activation is different depending on the ligand. In conclusion, our results demonstrate that, in mice brain native tissue, different exogenous cannabinoid ligands are able to selectively activate different inhibitory and non-inhibitory Gα protein subtypes, through the activation of CB1 and/or CB2 receptors. Results of the present study may help to understand the specific molecular pathways involved in the pharmacological effects of cannabinoid-derived drugs. PMID:27867358

  20. Hemispheric Asymmetry of Endogenous Neural Oscillations in Young Children: Implications for Hearing Speech In Noise. (United States)

    Thompson, Elaine C; Woodruff Carr, Kali; White-Schwoch, Travis; Tierney, Adam; Nicol, Trent; Kraus, Nina


    Speech signals contain information in hierarchical time scales, ranging from short-duration (e.g., phonemes) to long-duration cues (e.g., syllables, prosody). A theoretical framework to understand how the brain processes this hierarchy suggests that hemispheric lateralization enables specialized tracking of acoustic cues at different time scales, with the left and right hemispheres sampling at short (25 ms; 40 Hz) and long (200 ms; 5 Hz) periods, respectively. In adults, both speech-evoked and endogenous cortical rhythms are asymmetrical: low-frequency rhythms predominate in right auditory cortex, and high-frequency rhythms in left auditory cortex. It is unknown, however, whether endogenous resting state oscillations are similarly lateralized in children. We investigated cortical oscillations in children (3-5 years; N = 65) at rest and tested our hypotheses that this temporal asymmetry is evident early in life and facilitates recognition of speech in noise. We found a systematic pattern of increasing leftward asymmetry for higher frequency oscillations; this pattern was more pronounced in children who better perceived words in noise. The observed connection between left-biased cortical oscillations in phoneme-relevant frequencies and speech-in-noise perception suggests hemispheric specialization of endogenous oscillatory activity may support speech processing in challenging listening environments, and that this infrastructure is present during early childhood.

  1. Apraxia and spatial inattention dissociate in left hemisphere stroke. (United States)

    Timpert, David C; Weiss, Peter H; Vossel, Simone; Dovern, Anna; Fink, Gereon R


    Theories of lateralized cognitive functions propose a dominance of the left hemisphere for motor control and of the right hemisphere for spatial attention. Accordingly, spatial attention deficits (e.g., neglect) are more frequently observed after right-hemispheric stroke, whereas apraxia is a common consequence of left-hemispheric stroke. Clinical reports of spatial attentional deficits after left hemisphere (LH) stroke also exist, but are often neglected. By applying parallel analysis (PA) and voxel-based lesion-symptom mapping (VLSM) to data from a comprehensive neuropsychological assessment of 74 LH stroke patients, we here systematically investigate the relationship between spatial inattention and apraxia and their neural bases. PA revealed that apraxic (and language comprehension) deficits loaded on one common component, while deficits in attention tests were explained by another independent component. Statistical lesion analyses with the individual component scores showed that apraxic (and language comprehension) deficits were significantly associated with lesions of the left superior longitudinal fascicle (SLF). Data suggest that in LH stroke spatial attention deficits dissociate from apraxic (and language comprehension) deficits. These findings contribute to models of lateralised cognitive functions in the human brain. Moreover, our findings strongly suggest that LH stroke patients should be assessed systematically for spatial attention deficits so that these can be included in their rehabilitation regime.

  2. Association between the increase in brain temperature and physical performance at different exercise intensities and protocols in a temperate environment. (United States)

    Kunstetter, A C; Wanner, S P; Madeira, L G; Wilke, C F; Rodrigues, L O C; Lima, N R V


    There is evidence that brain temperature (T brain) provides a more sensitive index than other core body temperatures in determining physical performance. However, no study has addressed whether the association between performance and increases in T brain in a temperate environment is dependent upon exercise intensity, and this was the primary aim of the present study. Adult male Wistar rats were subjected to constant exercise at three different speeds (18, 21, and 24 m/min) until the onset of volitional fatigue. T brain was continuously measured by a thermistor inserted through a brain guide cannula. Exercise induced a speed-dependent increase in T brain, with the fastest speed associated with a higher rate of T brain increase. Rats subjected to constant exercise had similar T brain values at the time of fatigue, although a pronounced individual variability was observed (38.7-41.7°C). There were negative correlations between the rate of T brain increase and performance for all speeds that were studied. These results indicate that performance during constant exercise is negatively associated with the increase in T brain, particularly with its rate of increase. We then investigated how an incremental-speed protocol affected the association between the increase in T brain and performance. At volitional fatigue, T brain was lower during incremental exercise compared with the T brain resulting from constant exercise (39.3 ± 0.3 vs 40.3 ± 0.1°C; Pbrain increase and performance was observed. These findings suggest that the influence of T brain on performance under temperate conditions is dependent on exercise protocol.

  3. Brain activation evoked by erotic films varies with different menstrual phases: an fMRI study. (United States)

    Zhu, Xun; Wang, Xiaoying; Parkinson, Carolyn; Cai, Chengxu; Gao, Song; Hu, Peicheng


    In humans, fluctuating hormone levels throughout the menstrual cycle are believed to regulate many cyclical sexual behaviors and motivational processes. However, there is a dearth of research investigating the neural correlates of this phenomenon. We used functional magnetic resonance imaging to identify brain regions involved in sexual arousal's regulatory process. Fifteen female participants were scanned while viewing erotic film excerpts at three time points during a single menstrual cycle: ovulation, menstruation, and at one additional time point. Tripled two-group differences analysis revealed that significant activation in the comparison was observed in non-ovulatory phases of the menstrual cycle in parts of the right inferior frontal gyrus, right lateral occipital cortex, and left postcentral gyrus, as well as in the bilateral superior parietal lobule. Thus, our results indicate that brain activity differs in the ovulatory phase of the menstrual cycle compared to during other menstrual phases. This finding provides neurological evidence for the ovulatory cycle's modulation of the processing of the sexual arousal in female human brain.

  4. 大脑半球不对称性对急性脑梗死的影响%Influence of Hemispheric Asymmetry on Acute Ischemic Stroke

    Institute of Scientific and Technical Information of China (English)

    路雅宁; 于贤谨


    There is brain anatomy and function difference for the left and right hemispheres in the human brain. Numerous stud-ies have showed that there is the differences between left and right-hemispheric strokes, particularly in functional outcome, NIHSS score and imaging findings. New assement of the NIHSS toward left-hemispheric function is widely accepted. But the impact of hem-ispheric lateralization on clinical outcome is still unclear.%人的双侧大脑半球存在解剖学与功能性差异。有研究已经明确左侧大脑半球卒中和右侧大脑半球卒中存在差异,特别是在神经功能缺损、美国国立卫生研究院神经功能缺损评分( National Institutes of Health Stroke Scale, NIHSS)以及影像学检查等方面存在差异。 NIHSS评分偏重于对左侧大脑半球脑梗死评估等已经成为目前共识,但目前不同侧大脑半球对急性脑梗死的临床以及预后的具体影响仍存在着争议。

  5. Differences in brain 5-HT transporter dissociation rates among animal species

    Energy Technology Data Exchange (ETDEWEB)

    Erreboe, I.; Plenge, P.; Mellerup, E.T. [Univ. of Copenhagen, Dept. of Pharmacology, Lab. of Neuropsychiatry, Copenhagen (Denmark)


    The potential of using receptor-ligand dissociation rates as a model for investigating molecular changes in receptors was tested using the dissociation of [{sup 3}H]citalopram, [{sup 3}H]paroxetine and [{sup 3}H]imipramine from the brain 5-HT transporter of four different species (mouse, rat, pig and man). Since the dissociation rates of each of the three ligands differed in most of the species investigated, receptor-ligand dissociation rate constants would seem to be a sensitive measure of receptor conformation. The model could be useful in the search of structural variation in receptors whether attributable to genetic factors or to posttranslational modification. (au) (12 refs.).

  6. Species differences in brain gene expression profiles associated with adult behavioral maturation in honey bees

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    Robinson Gene E


    Full Text Available Abstract Background Honey bees are known for several striking social behaviors, including a complex pattern of behavioral maturation that gives rise to an age-related colony division of labor and a symbolic dance language, by which successful foragers communicate the location of attractive food sources to their nestmates. Our understanding of honey bees is mostly based on studies of the Western honey bee, Apis mellifera, even though there are 9–10 other members of genus Apis, showing interesting variations in social behavior relative to A. mellifera. To facilitate future in-depth genomic and molecular level comparisons of behavior across the genus, we performed a microarray analysis of brain gene expression for A. mellifera and three key species found in Asia, A. cerana, A. florea and A. dorsata. Results For each species we compared brain gene expression patterns between foragers and adult one-day-old bees on an A. mellifera cDNA microarray and calculated within-species gene expression ratios to facilitate cross-species analysis. The number of cDNA spots showing hybridization fluorescence intensities above the experimental threshold was reduced by an average of 16% in the Asian species compared to A. mellifera, but an average of 71% of genes on the microarray were available for analysis. Brain gene expression profiles between foragers and one-day-olds showed differences that are consistent with a previous study on A. mellifera and were comparable across species. Although 1772 genes showed significant differences in expression between foragers and one-day-olds, only 218 genes showed differences in forager/one-day-old expression between species (p Conclusion We conclude that the A. mellifera cDNA microarray can be used effectively for cross-species comparisons within the genus. Our results indicate that there is a widespread conservation of the molecular processes in the honey bee brain underlying behavioral maturation. Species differences in

  7. Sex differences in associations of arginine vasopressin and oxytocin with resting-state functional brain connectivity. (United States)

    Rubin, Leah H; Yao, Li; Keedy, Sarah K; Reilly, James L; Bishop, Jeffrey R; Carter, C Sue; Pournajafi-Nazarloo, Hossein; Drogos, Lauren L; Tamminga, Carol A; Pearlson, Godfrey D; Keshavan, Matcheri S; Clementz, Brett A; Hill, Scot K; Liao, Wei; Ji, Gong-Jun; Lui, Su; Sweeney, John A


    Oxytocin (OT) and arginine vasopressin (AVP) exert robust and sexually dimorphic influences on cognition and emotion. How these hormones regulate relevant functional brain systems is not well understood. OT and AVP serum concentrations were assayed in 60 healthy individuals (36 women). Brain functional networks assessed with resting-state functional magnetic resonance imaging (rs-fMRI) were constructed with graph theory-based approaches that characterize brain networks as connected nodes. Sex differences were demonstrated in rs-fMRI. Men showed higher nodal degree (connectedness) and efficiency (information propagation capacity) in left inferior frontal gyrus (IFG) and bilateral superior temporal gyrus (STG) and higher nodal degree in left rolandic operculum. Women showed higher nodal betweenness (being part of paths between nodes) in right putamen and left inferior parietal gyrus (IPG). Higher hormone levels were associated with less intrinsic connectivity. In men, higher AVP was associated with lower nodal degree and efficiency in left IFG (pars orbitalis) and left STG and less efficiency in left IFG (pars triangularis). In women, higher AVP was associated with lower betweenness in left IPG, and higher OT was associated with lower nodal degree in left IFG (pars orbitalis). Hormones differentially correlate with brain networks that are important for emotion processing and cognition in men and women. AVP in men and OT in women may regulate orbital frontal cortex connectivity, which is important in emotion processing. Hormone associations with STG and pars triangularis in men and parietal cortex in women may account for well-established sex differences in verbal and visuospatial abilities, respectively. © 2016 Wiley Periodicals, Inc.

  8. Topological organization of functional brain networks in healthy children: differences in relation to age, sex, and intelligence.

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    Kai Wu

    Full Text Available Recent studies have demonstrated developmental changes of functional brain networks derived from functional connectivity using graph theoretical analysis, which has been rapidly translated to studies of brain network organization. However, little is known about sex- and IQ-related differences in the topological organization of functional brain networks during development. In this study, resting-state fMRI (rs-fMRI was used to map the functional brain networks in 51 healthy children. We then investigated the effects of age, sex, and IQ on economic small-world properties and regional nodal properties of the functional brain networks. At a global level of whole networks, we found significant age-related increases in the small-worldness and local efficiency, significant higher values of the global efficiency in boys compared with girls, and no significant IQ-related difference. Age-related increases in the regional nodal properties were found predominately in the frontal brain regions, whereas the parietal, temporal, and occipital brain regions showed age-related decreases. Significant sex-related differences in the regional nodal properties were found in various brain regions, primarily related to the default mode, language, and vision systems. Positive correlations between IQ and the regional nodal properties were found in several brain regions related to the attention system, whereas negative correlations were found in various brain regions primarily involved in the default mode, emotion, and language systems. Together, our findings of the network topology of the functional brain networks in healthy children and its relationship with age, sex, and IQ bring new insights into the understanding of brain maturation and cognitive development during childhood and adolescence.

  9. On the Relationship between Right- brain and Left- brain Dominance and Reading Comprehension Test Performance of Iranian EFL Learners

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    Hassan Soleimani


    Full Text Available A tremendous amount of works have been conducted by psycholinguistics to identify hemisphere processing during second/ foreign language learning, or in other words to investigate the role of the brain hemisphere dominance in language performance of learners. Most of these researches have focused on single words and word pairs (e.g., Anaki et al., 1998; Arzouan et. al., 2007; Faust & Mahal, 2007 or simple sentences (Rapp et al., 2007; Kacinik & Chiarello, 2007, and it has been discovered that there is an advantage of right hemisphere for metaphors and an
    advantage of left hemisphere for literal text. But the present research was designed to study Iranian EFL learners' performance in different reading tasks, so there could be differences between the consequences of the former research and the results of the present study due to the context. Here left-brain and right-brain dominance was investigated in 60 individuals (20 right-handed and 10 left-handed male, 20 right-handed and 10 left-handed female via the Edinburg Handedness Questionnaire (EHQ. The research results suggested that the right-handed learners who are supposed to be left-brain outperformed the left-handed ones; and regarding participant's gender, male learners outperformed female learners on reading comprehension test tasks.

  10. Variation of space radiation exposure inside spherical and hemispherical geometries

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    Lin, Z.W. [Department of Physics, East Carolina University, C-209 Howell Science Complex, Greenville, NC 27858-4353 (United States); National Space Science and Technology Center, University of Alabama in Huntsville, Huntsville, AL 35805 (United States)], E-mail:; Baalla, Y. [University of Tennessee Space Institute, Tullahoma, TN 37388 (United States); Townsend, L.W. [Department of Nuclear Engineering, University of Tennessee at Knoxville, Knoxville, TN 37996 (United States)


    We calculate the space radiation exposure to blood-forming organs everywhere inside a hemispherical dome that represents a lunar habitat. We derive the analytical pathlength distribution from any point inside a hemispherical or a spherical shell. Because the average pathlength increases with the distance from the center, the center of the hemispherical dome on the lunar surface has the largest radiation exposure while locations on the inner surface of the dome have the lowest exposure. This conclusion differs from an earlier study on a hemispherical dome but agrees with another earlier study on a spherical-shell shield. We also find that the reduction in the radiation exposure from the center to the inner edge of the dome can be as large as a factor of 3 or more for the radiation from solar particle events while being smaller for the radiation from galactic cosmic rays.

  11. Developmental dyslexia: dysfunction of a left hemisphere reading network

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    Fabio eRichlan


    Full Text Available This mini-review summarizes and integrates findings from recent meta-analyses and original neuroimaging studies on functional brain abnormalities in dyslexic readers. Surprisingly, there is little empirical support for the standard neuroanatomical model of developmental dyslexia, which localizes the primary phonological decoding deficit in left temporo-parietal regions. Rather, recent evidence points to a dysfunction of a left hemisphere reading network, which includes occipito-temporal, inferior frontal, and inferior parietal regions.

  12. Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

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    Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew [The University of Melbourne, Departments of Medicine and Neurology, Melbourne Brain Centre rate at The Royal Melbourne Hospital, Parkville, Victoria (Australia); Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M. [The University of Melbourne, Department of Radiology, The Royal Melbourne Hospital, Parkville (Australia); Churilov, Leonid [The University of Melbourne, The Florey Institute of Neurosciences and Mental Health, Parkville (Australia); Parsons, Mark W. [University of Newcastle and Hunter Medical Research Institute, Priority Research Centre for Translational Neuroscience and Mental Health, Newcastle (Australia)


    Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

  13. Seasonal and regional differences in gene expression in the brain of a hibernating mammal.

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    Christine Schwartz

    Full Text Available Mammalian hibernation presents a unique opportunity to study naturally occurring neuroprotection. Hibernating ground squirrels undergo rapid and extreme physiological changes in body temperature, oxygen consumption, and heart rate without suffering neurological damage from ischemia and reperfusion injury. Different brain regions show markedly different activity during the torpor/arousal cycle: the cerebral cortex shows activity only during the periodic returns to normothermia, while the hypothalamus is active over the entire temperature range. Therefore, region-specific neuroprotective strategies must exist to permit this compartmentalized spectrum of activity. In this study, we use the Illumina HiSeq platform to compare the transcriptomes of these two brain regions at four collection points across the hibernation season: April Active, October Active, Torpor, and IBA. In the cerebral cortex, 1,085 genes were found to be differentially expressed across collection points, while 1,063 genes were differentially expressed in the hypothalamus. Comparison of these transcripts indicates that the cerebral cortex and hypothalamus implement very different strategies during hibernation, showing less than 20% of these differentially expressed genes in common. The cerebral cortex transcriptome shows evidence of remodeling and plasticity during hibernation, including transcripts for the presynaptic cytomatrix proteins bassoon and piccolo, and extracellular matrix components, including laminins and collagens. Conversely, the hypothalamic transcriptome displays upregulation of transcripts involved in damage response signaling and protein turnover during hibernation, including the DNA damage repair gene RAD50 and ubiquitin E3 ligases UBR1 and UBR5. Additionally, the hypothalamus transcriptome also provides evidence of potential mechanisms underlying the hibernation phenotype, including feeding and satiety signaling, seasonal timing mechanisms, and fuel

  14. The brain structure correlates of individual differences in trait mindfulness: a voxel-based morphometry study. (United States)

    Lu, H; Song, Y; Xu, M; Wang, X; Li, X; Liu, J


    Mindfulness is the state of being attentive to and aware of what is taking place in the present, which is beneficial for reducing stress-related symptoms and improving mental and physical health. Previous studies have demonstrated that meditation practice can improve individuals' mindfulness through modifying functions and structures of multiple brain regions, including the anterior cingulate cortex (ACC), insula, fronto-limbic network, posterior cingulate cortex (PCC), and temporal-parietal junction. However, little is known about the neuroanatomical correlates of trait mindfulness. In the current study, we used voxel-based morphometry to investigate the neural correlates of individual differences in trait mindfulness by correlating the gray matter (GM) volume of each voxel across the whole brain with trait mindfulness measured by the Mindful Attention Awareness Scale in a large sample of young adults (N=247). We found that individuals who were more mindful of the present had greater GM volume in the right hippocampus/amygdala and bilateral ACC, but less GM volume in bilateral PCC and the left orbitofrontal cortex. These results suggest that trait mindfulness is associated with brain regions involved in executive attention, emotion regulation, and self-referential processing, through which mindfulness may exert its beneficial effects on psychological and physical well-being.


    Hoss, Andrew G.; Lagomarsino, Valentina N.; Frank, Samuel; Hadzi, Tiffany C.; Myers, Richard H.; Latourelle, Jeanne C.


    Background Biomarkers for Huntington’s disease (HD) progression could accelerate therapeutic developments and improve patient care. Brain microRNAs (miRNA) relating to clinical features of HD may represent a potential HD biomarker in blood. Objective Examine candidate miRNAs in plasma to determine if changes observed in HD brains are detectable in peripheral samples. Methods Four miRNA from 26 manifest HD, 4 asymptomatic HD gene carriers and 8 controls were quantified in plasma using RT-qPCR. Linear regression was used to assess miRNA levels across control, asymptomatic gene carriers and manifest patients. Results miR-10b-5p (p= 0.0068) and miR-486-5p (p= 0.044) were elevated in HD plasma. miR-10b-5p was decreased in asymptomatic gene carriers as compared to HD patients (p= 0.049), but no difference between asymptomatic gene carriers and controls was observed (p= 0.24). Conclusions These findings suggest miRNA changes observed in HD brain may be detectable in plasma and have potential clinical utility. PMID:26573701

  16. Differences between in vitro and in vivo degradation of LHRH by rat brain and other organs

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    Carone, F.A.; Stetler-Stevenson, M.A.; May, V.; LaBarbera, A.; Flouret, G.


    Homogenates of brain, pituitary, liver, lung, ovary, and testes were incubated with (different times intervals, metabolites 2, 3, 4, and 5, and in some instances 7 and 9, appeared to form simultaneously and were detectable at 10 min. Neither metabolite 6 nor other larger metabolites formed initially as dominant degradation products. The findings suggest cleavage of LHRH by the simultaneous action of several endopeptidases. After a single vascular transit of (/sup 3/H)LHRH, metabolites were determined in the venous blood of liver, lung, and brain of rats in vivo. There were no metabolites of (/sup 3/H)LHRH in venous blood liver and lung; however, metabolites 2-4 present in venous blood of the brain. Incubation of rat anterior pituitary cells with (/sup 3/H)LHRH yielded metabolites 1-4 but not metabolites 5 or 9 as in homogenates. Incubation of (/sup 3/H)LHRH with porcine follicular granulosa cells resulted in the generation of metabolites 2-7 and 9, similar to the profile in homogenates. Thus, since homogenates contain enzymes of disrupted cells, they do not always reflect mechanisms for in vivo hydrolysis of circulating LHRH. Brain degraded 12.1% of LHRH during a single vascular transit and may account for substantial degradation of the circulating hormone.

  17. Individual differences in true and false memory retrieval are related to white matter brain microstructure. (United States)

    Fuentemilla, Lluís; Càmara, Estela; Münte, Thomas F; Krämer, Ulrike M; Cunillera, Toni; Marco-Pallarés, Josep; Tempelmann, Claus; Rodriguez-Fornells, Antoni


    We sometimes vividly remember things that did not happen, a phenomenon with general relevance, not only in the courtroom. It is unclear to what extent individual differences in false memories are driven by anatomical differences in memory-relevant brain regions. Here we show in humans that microstructural properties of different white matter tracts as quantified using diffusion tensor imaging are strongly correlated with true and false memory retrieval. To investigate these hypotheses, we tested a large group of participants in a version of the Deese-Roediger-McDermott paradigm (recall and recognition) and subsequently obtained diffusion tensor images. A voxel-based whole-brain level linear regression analysis was performed to relate fractional anisotropy to indices of true and false memory recall and recognition. True memory was correlated to diffusion anisotropy in the inferior longitudinal fascicle, the major connective pathway of the medial temporal lobe, whereas a greater proneness to retrieve false items was related to the superior longitudinal fascicle connecting frontoparietal structures. Our results show that individual differences in white matter microstructure underlie true and false memory performance.

  18. Differences between oral and written calculation: evidence from cognitive neuropsychology from six brain-damaged patients

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    María P. Salguero-Alcañiz


    Full Text Available Introduction: The study of patients with acquired brain injury shows the existence of several double dissociations in the calculation system. In this paper, we focus on the double dissociation observed between oral and written calculation. Method: Instrument: Battery of Evaluation and Numerical Processing and Calculation. Participants: Six patients with acquired brain injury who have different alterations in the processing of numbers and calculations. Data analysis: Difference of proportions. Results: MC and BET have impaired the written calculation but they preserve oral calculation (addition, subtraction and multiplication. The same is observed in MNL for addition and multiplication and in PP for subtraction. The reverse pattern is observed in IRS and ACH who have alterations in written calculation but preserve oral calculation (in multiplication and subtraction, respectively. Conclusions: The results demonstrate the functional independence of oral and written calculation. This could indicate that the calculation system is not unitary and responsible for any calculation task, but a multicomponential system involving different processes and of a different nature.

  19. Sex/gender differences in the brain and cognition in schizophrenia. (United States)

    Mendrek, Adrianna; Mancini-Marïe, Adham


    The early conceptualizations of schizophrenia have noted some sex/gender differences in epidemiology and clinical expression of the disorder. Over the past few decades, the interest in differences between male and female patients has expanded to encompass brain morphology and neurocognitive function. Despite some variability and methodological shortcomings, a few patterns emerge from the available literature. Most studies of gross neuroanatomy show more enlarged ventricles and smaller frontal lobes in men than in women with schizophrenia; finding reflecting normal sexual dimorphism. In comparison, studies of brain asymmetry and specific corticolimbic structures, suggest a disturbance in normal sexual dimorphism. The neurocognitive findings are somewhat consistent with this picture. Studies of cognitive functions mediated by the lateral frontal network tend to show sex differences in patients which are in the same direction as those observed in the general population, whereas studies of processes mediated by the corticolimbic system more frequently reveal reversal of normal sexual dimorphisms. These trends are faint and future research would need to delineate neurocognitive differences between men and women with various subtypes of schizophrenia (e.g., early versus late onset), while taking into consideration hormonal status and gender of tested participants.

  20. Cognitive alterations in motor imagery process after left hemispheric ischemic stroke.

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    Jing Yan

    Full Text Available BACKGROUND: Motor imagery training is a promising rehabilitation strategy for stroke patients. However, few studies had focused on the neural mechanisms in time course of its cognitive process. This study investigated the cognitive alterations after left hemispheric ischemic stroke during motor imagery task. METHODOLOGY/PRINCIPAL FINDINGS: Eleven patients with ischemic stroke in left hemisphere and eleven age-matched control subjects participated in mental rotation task (MRT of hand pictures. Behavior performance, event-related potential (ERP and event-related (desynchronization (ERD/ERS in beta band were analyzed to investigate the cortical activation. We found that: (1 The response time increased with orientation angles in both groups, called "angle effect", however, stoke patients' responses were impaired with significantly longer response time and lower accuracy rate; (2 In early visual perceptual cognitive process, stroke patients showed hypo-activations in frontal and central brain areas in aspects of both P200 and ERD; (3 During mental rotation process, P300 amplitude in control subjects decreased while angle increased, called "amplitude modulation effect", which was not observed in stroke patients. Spatially, patients showed significant lateralization of P300 with activation only in contralesional (right parietal cortex while control subjects showed P300 in both parietal lobes. Stroke patients also showed an overall cortical hypo-activation of ERD during this sub-stage; (4 In the response sub-stage, control subjects showed higher ERD values with more activated cortical areas particularly in the right hemisphere while angle increased, named "angle effect", which was not observed in stroke patients. In addition, stroke patients showed significant lower ERD for affected hand (right response than that for unaffected hand. CONCLUSIONS/SIGNIFICANCE: Cortical activation was altered differently in each cognitive sub-stage of motor imagery after

  1. Neuromagnetic index of hemispheric asymmetry prognosticating the outcome of sudden hearing loss.

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    Lieber Po-Hung Li

    Full Text Available The longitudinal relationship between central plastic changes and clinical presentations of peripheral hearing impairment remains unknown. Previously, we reported a unique plastic pattern of "healthy-side dominance" in acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL. This study aimed to explore whether such hemispheric asymmetry bears any prognostic relevance to ISSNHL along the disease course. Using magnetoencephalography (MEG, inter-hemispheric differences in peak dipole amplitude and latency of N100m to monaural tones were evaluated in 21 controls and 21 ISSNHL patients at two stages: initial and fixed stage (1 month later. Dynamics/Prognostication of hemispheric asymmetry were assessed by the interplay between hearing level/hearing gain and ipsilateral/contralateral ratio (I/C of N100m latency and amplitude. Healthy-side dominance of N100m amplitude was observed in ISSNHL initially. The pattern changed with disease process. There is a strong correlation between the hearing level at the fixed stage and initial I/C(amplitude on affected-ear stimulation in ISSNHL. The optimal cut-off value with the best prognostication effect for the hearing improvement at the fixed stage was an initial I/C(latency on affected-ear stimulation of 1.34 (between subgroups of complete and partial recovery and an initial I/C(latency on healthy-ear stimulation of 0.76 (between subgroups of partial and no recovery, respectively. This study suggested that a dynamic process of central auditory plasticity can be induced by peripheral lesions. The hemispheric asymmetry at the initial stage bears an excellent prognostic potential for the treatment outcomes and hearing level at the fixed stage in ISSNHL. Our study demonstrated that such brain signature of central auditory plasticity in terms of both N100m latency and amplitude at defined time can serve as a prognostication predictor for ISSNHL. Further studies are needed to explore the long

  2. Neuromagnetic index of hemispheric asymmetry prognosticating the outcome of sudden hearing loss. (United States)

    Li, Lieber Po-Hung; Shiao, An-Suey; Chen, Kuang-Chao; Lee, Po-Lei; Niddam, David M; Chang, Shyue-Yih; Hsieh, Jen-Chuen


    The longitudinal relationship between central plastic changes and clinical presentations of peripheral hearing impairment remains unknown. Previously, we reported a unique plastic pattern of "healthy-side dominance" in acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL). This study aimed to explore whether such hemispheric asymmetry bears any prognostic relevance to ISSNHL along the disease course. Using magnetoencephalography (MEG), inter-hemispheric differences in peak dipole amplitude and latency of N100m to monaural tones were evaluated in 21 controls and 21 ISSNHL patients at two stages: initial and fixed stage (1 month later). Dynamics/Prognostication of hemispheric asymmetry were assessed by the interplay between hearing level/hearing gain and ipsilateral/contralateral ratio (I/C) of N100m latency and amplitude. Healthy-side dominance of N100m amplitude was observed in ISSNHL initially. The pattern changed with disease process. There is a strong correlation between the hearing level at the fixed stage and initial I/C(amplitude) on affected-ear stimulation in ISSNHL. The optimal cut-off value with the best prognostication effect for the hearing improvement at the fixed stage was an initial I/C(latency) on affected-ear stimulation of 1.34 (between subgroups of complete and partial recovery) and an initial I/C(latency) on healthy-ear stimulation of 0.76 (between subgroups of partial and no recovery), respectively. This study suggested that a dynamic process of central auditory plasticity can be induced by peripheral lesions. The hemispheric asymmetry at the initial stage bears an excellent prognostic potential for the treatment outcomes and hearing level at the fixed stage in ISSNHL. Our study demonstrated that such brain signature of central auditory plasticity in terms of both N100m latency and amplitude at defined time can serve as a prognostication predictor for ISSNHL. Further studies are needed to explore the long-term temporal scenario

  3. An ERP investigation of the co-development of hemispheric lateralization of face and word recognition. (United States)

    Dundas, Eva M; Plaut, David C; Behrmann, Marlene


    The adult human brain would appear to have specialized and independent neural systems for the visual processing of words and faces. Extensive evidence has demonstrated greater selectivity for written words in the left over right hemisphere, and, conversely, greater selectivity for faces in the right over left hemisphere. This study examines the emergence of these complementary neural profiles, as well as the possible relationship between them. Using behavioral and neurophysiological measures, in adults, we observed the standard finding of greater accuracy and a larger N170 ERP component in the left over right hemisphere for words, and conversely, greater accuracy and a larger N170 in the right over the left hemisphere for faces. We also found that although children aged 7-12 years revealed the adult hemispheric pattern for words, they showed neither a behavioral nor a neural hemispheric superiority for faces. Of particular interest, the magnitude of their N170 for faces in the right hemisphere was related to that of the N170 for words in their left hemisphere. These findings suggest that the hemispheric organization of face recognition and of word recognition does not develop independently, and that word lateralization may precede and drive later face lateralization. A theoretical account for the findings, in which competition for visual representations unfolds over the course of development, is discussed.

  4. The influence of sex differences and individual task performance on brain activation during planning. (United States)

    Unterrainer, J M; Ruff, C C; Rahm, B; Kaller, C P; Spreer, J; Schwarzwald, R; Halsband, U


    Several studies have attempted to identify the neuronal basis of sex differences in cognition. However, group differences in cognitive ability rather than genuine neurocognitive differences between the sexes may account for their results. Here, we compare with functional magnetic resonance imaging the relation between gender, individual task performance, and planning-related brain activation. Men and women preselected to display identical performance scores showed a strong relation between individual task performance and activation of the right dorsolateral prefrontal and right inferior parietal cortex activation during a visuospatial planning task. No gender-specific activations were found. However, a different pattern emerged when subjects had to execute the motor responses to the problems. Better performance was associated with right dorsolateral prefrontal and right parahippocampal activations, and females exhibited a stronger right hippocampal activation than males. These findings underline that an individual's performance level rather than his or her sex largely determines the neuronal activation patterns during higher-level cognition.

  5. Regional brain differences in cortical thickness, surface area and subcortical volume in individuals with Williams syndrome.

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    Shashwath A Meda

    Full Text Available Williams syndrome (WS is a rare genetic neurodevelopmental disorder characterized by increased non-social anxiety, sensitivity to sounds and hypersociability. Previous studies have reported contradictory findings with regard to regional brain variation in WS, relying on only one type of morphological measure (usually volume in each study. The present study aims to contribute to this body of literature and perhaps elucidate some of these discrepancies by examining concurrent measures of cortical thickness, surface area and subcortical volume between WS subjects and typically-developing (TD controls. High resolution MRI scans were obtained on 31 WS subjects and 50 typically developing control subjects. We derived quantitative regional estimates of cortical thickness, cortical surface area, and subcortical volume using FreeSurfer software. We evaluated between-group ROI differences while controlling for total intracranial volume. In post-hoc exploratory analyses within the WS group, we tested for correlations between regional brain variation and Beck Anxiety Inventory scores. Consistent with our hypothesis, we detected complex patterns of between-group cortical variation, which included lower surface area in combination with greater thickness in the following cortical regions: post central gyrus, cuneus, lateral orbitofrontal cortex and lingual gyrus. Additional cortical regions showed between-group differences in one (but not both morphological measures. Subcortical volume was lower in the basal ganglia and the hippocampus in WS versus TD controls. Exploratory correlations revealed that anxiety scores were negatively correlated with gray matter surface area in insula, OFC, rostral middle frontal, superior temporal and lingual gyrus. Our results were consistent with previous reports showing structural alterations in regions supporting the socio-affective and visuospatial impairments in WS. However, we also were able to effectively capture novel and

  6. Regional brain differences in cortical thickness, surface area and subcortical volume in individuals with Williams syndrome. (United States)

    Meda, Shashwath A; Pryweller, Jennifer R; Thornton-Wells, Tricia A


    Williams syndrome (WS) is a rare genetic neurodevelopmental disorder characterized by increased non-social anxiety, sensitivity to sounds and hypersociability. Previous studies have reported contradictory findings with regard to regional brain variation in WS, relying on only one type of morphological measure (usually volume) in each study. The present study aims to contribute to this body of literature and perhaps elucidate some of these discrepancies by examining concurrent measures of cortical thickness, surface area and subcortical volume between WS subjects and typically-developing (TD) controls. High resolution MRI scans were obtained on 31 WS subjects and 50 typically developing control subjects. We derived quantitative regional estimates of cortical thickness, cortical surface area, and subcortical volume using FreeSurfer software. We evaluated between-group ROI differences while controlling for total intracranial volume. In post-hoc exploratory analyses within the WS group, we tested for correlations between regional brain variation and Beck Anxiety Inventory scores. Consistent with our hypothesis, we detected complex patterns of between-group cortical variation, which included lower surface area in combination with greater thickness in the following cortical regions: post central gyrus, cuneus, lateral orbitofrontal cortex and lingual gyrus. Additional cortical regions showed between-group differences in one (but not both) morphological measures. Subcortical volume was lower in the basal ganglia and the hippocampus in WS versus TD controls. Exploratory correlations revealed that anxiety scores were negatively correlated with gray matter surface area in insula, OFC, rostral middle frontal, superior temporal and lingual gyrus. Our results were consistent with previous reports showing structural alterations in regions supporting the socio-affective and visuospatial impairments in WS. However, we also were able to effectively capture novel and complex

  7. Sex differences in brain aromatase activity: genomic and non-genomic controls

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    Jacques eBalthazart


    Full Text Available Aromatization of testosterone into estradiol in the preoptic area plays a critical role in the activation of male copulation in quail and in many other vertebrate species. Aromatase expression in quail and in other birds is higher than in rodents and other mammals, which has facilitated the study of the controls and functions of this enzyme. Over relatively long time periods (days to months, brain aromatase activity and transcription are markedly (4-6 fold increased by genomic actions of sex steroids. Initial work indicated that the preoptic aromatase activity is higher in males than in females and it was hypothesized that this differential production of estrogen could be a critical factor responsible for the lack of behavioral activation in females. Subsequent studies revealed, however, that this enzymatic sex difference might contribute but is not sufficient to explain the sex difference in behavior. Studies of aromatase activity, immunoreactivity and mRNA concentrations revealed that sex differences observed when measuring enzymatic activity are not necessarily observed when one measures mRNA concentrations. Discrepancies potentially reflect post-translational controls of the enzymatic activity. Aromatase activity in quail brain homogenates is rapidly inhibited by phosphorylation processes. Similar rapid inhibitions occur in hypothalamic explants maintained in vitro and exposed to agents affecting intracellular calcium concentrations or to glutamate agonists. Rapid changes in aromatase activity have also been observed in vivo following sexual interactions or exposure to short-term restraint stress and these rapid changes in estrogen production modulate expression of male sexual behaviors. These data suggest that brain estrogens display most if not all characteristics of neuromodulators if not neurotransmitters. Many questions remain however concerning the mechanisms controlling these rapid changes in estrogen production and their behavioral

  8. Neuropragmatics: Extralinguistic pragmatic ability is better preserved in left-hemisphere-damaged patients than in right-hemisphere-damaged patients. (United States)

    Cutica, Ilaria; Bucciarelli, Monica; Bara, Bruno G


    The aim of the present study is to compare the pragmatic ability of right- and left-hemisphere-damaged patients excluding the possible interference of linguistic deficits. To this aim, we study extralinguistic communication, that is communication performed only through gestures. The Cognitive Pragmatics Theory provides the theoretical framework: it predicts a gradient of difficulty in the comprehension of different pragmatic phenomena, that should be valid independently of the use of language or gestures as communicative means. An experiment involving 10 healthy individuals, 10 right- and 9 left-hemisphere-damaged patients, shows that pragmatic performance is better preserved in left-hemisphere-damaged (LHD) patients than in right-hemisphere-damaged (RHD) patients.

  9. Healthy children show gender differences in correlations between nonverbal cognitive ability and brain activation during visual perception. (United States)

    Asano, Kohei; Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Thyreau, Benjamin; Asano, Michiko; Takeuchi, Hikaru; Kawashima, Ryuta


    Humans perceive textual and nontextual information in visual perception, and both depend on language. In childhood education, students exhibit diverse perceptual abilities, such that some students process textual information better and some process nontextual information better. These predispositions involve many factors, including cognitive ability and learning preference. However, the relationship between verbal and nonverbal cognitive abilities and brain activation during visual perception has not yet been examined in children. We used functional magnetic resonance imaging to examine the relationship between nonverbal and verbal cognitive abilities and brain activation during nontextual visual perception in large numbers of children. A significant positive correlation was found between nonverbal cognitive abilities and brain activation in the right temporoparietal junction, which is thought to be related to attention reorienting. This significant positive correlation existed only in boys. These findings suggested that male brain activation differed from female brain activation, and that this depended on individual cognitive processes, even if there was no gender difference in behavioral performance.

  10. Structural and functional brain changes related to different types of physical activity across the life span. (United States)

    Voelcker-Rehage, Claudia; Niemann, Claudia


    Physical activity has been shown to improve cognitive functioning. Research has largely focused on cognitive facilitation by cardiovascular exercise in older adults. Only few studies have investigated younger age groups or other types of physical activity. In this paper we review and summarize common results found in recent studies of metabolic (i.e. cardiovascular and resistance) and coordinative exercise. Findings from human motor learning are utilized to complement results on coordinative exercise. Results show that both types of exercise affect the brain differently. We propose possible mechanisms by which physical activity facilitates cognitive performance by briefly reviewing microscopic structural changes in animal research. Lastly, we highlight open research questions.

  11. Abnormal Asymmetry of Brain Connectivity in Schizophrenia


    Ribolsi, Michele; Zafiris J Daskalakis; Siracusano, Alberto; Koch, Giacomo


    Recently, a growing body of data has revealed that beyond a dysfunction of connectivity among different brain areas in schizophrenia patients (SCZ), there is also an abnormal asymmetry of functional connectivity compared with healthy subjects. The loss of the cerebral torque and the abnormalities of gyrification, with an increased or more complex cortical folding in the right hemisphere may provide an anatomical basis for such aberrant connectivity in SCZ. Furthermore, diffusion tensor imagin...

  12. Effects of different kinds of acute stress on nerve growth factor content in rat brain. (United States)

    von Richthofen, Sita; Lang, Undine E; Hellweg, Rainer


    Nerve growth factor (NGF) has several effects on the central nervous system; on the one hand NGF fosters survival and function of cholinergic neurons of the basal forebrain, on the other hand this protein is implicated in the stress response of the hypothalamic-pituitary-adrenocortical axis (HPAA). In this study we tested the influence of threatening and painful stress treatments in three different intensities as well as forced motoric activity on NGF content in different brain areas in adult rats. We found that threatening treatment with or without painful stimuli was followed by a significant decrease of NGF concentration in the amygdala (44.5%; P=0.03) and the frontal cortex (-45.5%; P=0.02). We also observed that after stress of forced motoric activity NGF content in the frontal cortex (-32%; P=0.01) and the hippocampus (-32%; P=0.006) was significantly reduced. Thus, NGF content in distinct brain regions is decreased, following different forms of acute stress. This might be relevant for the pathophysiological understanding of psychiatric diseases, such as depression, which are associated with stress.

  13. Different protocols of treadmill exercise induce distinct neuroplastic effects in rat brain motor areas. (United States)

    Real, Caroline C; Garcia, Priscila C; Britto, Luiz R G; Pires, Raquel S


    A variety of exercise protocols have been used to promote experimental neuroplasticity. However, the plastic brain responses generated by several aspects of training (types, frequency, regimens, duration) remain undetermined. The aim of this study was to compare the plastic changes in the glutamatergic system and synaptic proteins in motor cortex, striatum and cerebellum promoted by two different treadmill exercise regimens. The present study analyzed by immunohistochemistry and Western blotting the expression of the subunits of AMPA receptors (GluA1 and GluA2/3) and synaptic proteins (synapsin I and synaptophysin) in adult male Wistar rat brains. The animals were divided into animals subjected to two different frequencies of aerobic exercise groups and sedentary animals. The exercise groups were: intermittent treadmill exercise (ITE) - animals that exercised 3 times a week (every other day) during four weeks, and continuous treadmill exercise (CTE) - animals that exercised every day during four weeks. Our results reveal that different protocols of treadmill exercise were able to promote distinct synaptic reorganization processes among the exercised groups. In general, the intermittent exercise regimen induced a higher expression of presynaptic proteins, whereas the continuous exercise regimen increased postsynaptic GluA1 and GluA2/3 receptors.

  14. Interleukin-1 exerts distinct actions on different cell types of the brain in vitro

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    Ying An


    Full Text Available Ying An, Qun Chen, Ning QuanDepartment of Oral Biology, Ohio State University, Columbus, OH, USAAbstract: Interleukin-1 (IL-1 is a critical neuroinflammatory mediator in the central nervous system (CNS. In this study, we investigated the effect of IL-1 on inducing inflammation-related gene expression in three astrocyte, two microglial, and one brain endothelial cell line. Interleukin-1 beta (IL-1β is found to be produced by the two microglial cell lines constitutively, but these cells do not respond to IL-1β stimulation. The three astrocyte cell lines responded to IL-1ß stimulation by expressing MCP-1, CXCL-1, and VCAM-1, but different subtypes of astrocytes exhibited different expression profiles after IL-1β stimulation. The brain endothelial cells showed strongest response to IL-1β by producing MCP-1, CXCL-1, VCAM-1, ICAM-1, IL-6, and COX-2 mRNA. The induction of endothelial COX-2 mRNA is shown to be mediated by p38 MAPK pathway, whereas the induction of other genes is mediated by the NF-κB pathway. These results demonstrate that IL-1 exerts distinct cell type-specific action in CNS cells and suggest that IL-1-mediated neuroinflammation is the result of the summation of multiple responses from different cell types in the CNS to IL-1.Keywords: astrocyte, microglia, endothelial cells, signal transduction pathways, gene expression 

  15. Gender differences in brain development in Chinese children and adolescents: a structural MRI study (United States)

    Guo, Xiaojuan; Jin, Zhen; Chen, Kewei; Peng, Danling; Yao, Li


    Using optimized voxel-based morphometry (VBM), this study systematically investigated gender differences in brain development through magnetic resonance imaging (MRI) data in 158 Chinese normal children and adolescents aged 7.26 to 22.80 years (mean age 15.03+/-4.70 years, 78 boys and 80 girls). Gender groups were matched for measures of age, handedness, education level. The customized brain templates, including T I-weighted image and gray matter (GM)/white matter (WM)/cerebro-spinal fluid (CSF) prior probability maps, were created from all participants. Results showed that the total intracranial volume (TIV), global absolute GM and global WM volume in girls were significantly smaller than those in boys. The hippocampus grew faster in girls than that in boys, but the amygdala grew faster in boys than that in girls. The rate of regional GM decreases with age was steeper in the left superior parietal lobule, bilateral inferior parietal lobule, left precuneus, and bilateral supramarginal gyrus in boys compared to girls, which was possibly related to better spatial processing ability in boys. Regional GM volumes were greater in bilateral superior temporal gyrus, bilateral inferior frontal gyrus and bilateral middle frontal gyrus in girls. Regional WM volumes were greater in the left temporal lobe, right inferior parietal and bilateral middle frontal gyrus in girls. The gender differences in the temporal and frontal lobe maybe be related to better language ability in girls. These findings may aid in understanding the differences in cognitive function between boys and girls.

  16. Non-conjugate aurora and inter hemispheric currents (United States)

    Reistad, J. P.; Østgaard, N.; Laundal, K. M.; Oksavik, K.


    We look at large scale auroral features using global imagers to obtain simultaneous pictures of both the southern and northern auroral ovals in the ultra violet part of the spectra. During the years 2001 and 2002 the IMAGE satellite was in a favourable position for imaging the aurora borealis (Northern Hemisphere) and the POLAR satellite with its large field-of-view VIS Earth camera had a sporadic coverage of the aurora australis (Southern Hemisphere). In total 19 hours of simultaneous global imaging from different seasons are analysed searching for non-conjugacy in the night side sector. By non-conjugate aurora we mean auroral features appearing in one hemisphere only, or significant differences in intensity between the hemispheres for the same auroral feature. We suggest that our observed large scale asymmetries can be explained in terms of inter hemispheric currents (IHC). Coherent with our earlier findings, we list three possible candidates for producing such inter hemispheric currents based on observations. 1) Hemispherical differences in the solar wind dynamo due to IMF Bx and tilt angle producing different strength of region 1 currents in the conjugate he mispheres, 2) Hemispherical differences in conductivity controlled by the tilt angle only giving rise to IHC on closed field lines, and 3) Field-aligned current components induced by the penetration of the IMF By into the closed magnetosphere. Most of the observed non-conjugate aurora in our dataset can be explained by these candidates only. The IMF By penetration candidate is considered closer. We search for evidence in our data that IMF By 0) can induce an IHC producing stronger aurora on the polar boundary in the Northern (Southern) Hemisphere. Also a second IHC component are predicted from the theory, mapping to the equatorward part of the oval and opposite directed along the magnetic field lines. Using a much larger dataset for one hemisphere only, we show whether these predicted currents can be

  17. Asymmetry of the Brain: Development and Implications. (United States)

    Duboc, Véronique; Dufourcq, Pascale; Blader, Patrick; Roussigné, Myriam


    Although the left and right hemispheres of our brains develop with a high degree of symmetry at both the anatomical and functional levels, it has become clear that subtle structural differences exist between the two sides and that each is dominant in processing specific cognitive tasks. As the result of evolutionary conservation or convergence, lateralization of the brain is found in both vertebrates and invertebrates, suggesting that it provides significant fitness for animal life. This widespread feature of hemispheric specialization has allowed the emergence of model systems to study its development and, in some cases, to link anatomical asymmetries to brain function and behavior. Here, we present some of what is known about brain asymmetry in humans and model organisms as well as what is known about the impact of environmental and genetic factors on brain asymmetry development. We specifically highlight the progress made in understanding the development of epithalamic asymmetries in zebrafish and how this model provides an exciting opportunity to address brain asymmetry at different levels of complexity.

  18. Early left-hemispheric dysfunction of face processing in congenital prosopagnosia: an MEG study.

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    Christian Dobel

    Full Text Available BACKGROUND: Congenital prosopagnosia is a severe face perception impairment which is not acquired by a brain lesion and is presumably present from birth. It manifests mostly by an inability to recognise familiar persons. Electrophysiological research has demonstrated the relevance to face processing of a negative deflection peaking around 170 ms, labelled accordingly as N170 in the electroencephalogram (EEG and M170 in magnetoencephalography (MEG. The M170 was shown to be sensitive to the inversion of faces and to familiarity--two factors that are assumed to be crucial for congenital prosopagnosia. In order to locate the cognitive dysfunction and its neural correlates, we investigated the time course of neural activity in response to these manipulations. METHODOLOGY: Seven individuals with congenital prosopagnosia and seven matched controls participated in the experiment. To explore brain activity with high accuracy in time, we recorded evoked magnetic fields (275 channel whole head MEG while participants were looking at faces differing in familiarity (famous vs. unknown and orientation (upright vs. inverted. The underlying neural sources were estimated by means of the least square minimum-norm-estimation (L2-MNE approach. PRINCIPAL FINDINGS: The behavioural data corroborate earlier findings on impaired configural processing in congenital prosopagnosia. For the M170, the overall results replicated earlier findings, with larger occipito-temporal brain responses to inverted than upright faces, and more right- than left-hemispheric activity. Compared to controls, participants with congenital prosopagnosia displayed a general decrease in brain activity, primarily over left occipitotemporal areas. This attenuation did not interact with familiarity or orientation. CONCLUSIONS: The study substantiates the finding of an early involvement of the left hemisphere in symptoms of prosopagnosia. This might be related to an efficient and overused featural

  19. To modulate or not to modulate: differing results in uniquely shaped Williams syndrome brains. (United States)

    Eckert, Mark A; Tenforde, Adam; Galaburda, Albert M; Bellugi, Ursula; Korenberg, Julie R; Mills, Debra; Reiss, Allan L


    Voxel based morphometry (VBM) studies of Williams syndrome (WS) have demonstrated remarkably consistent findings of reduced posterior parietal gray matter compared to typical controls. Other WS VBM findings have been inconsistent, however. In particular, different findings have been reported for hypothalamus and orbitofrontal gray matter regions. We examined a sample of 8 WS and 9 control adults and show that the hypothalamus and orbitofrontal cortex results depend on whether the images undergo Jacobian modulation. Deformation based morphometry (DBM) analysis demonstrated that major brain shape differences between the groups accounted for the Jacobian modulated gray matter findings. These results indicate that cautious interpretations of modulated gray matter findings are warranted when there are gross shape and size differences between experimental groups. This study demonstrates the importance of methodological choices towards understanding a disorder like WS, but also highlights the consistency of parietal lobe, orbitofrontal, and midbrain findings for this disorder across methodologies, participants, and research groups.

  20. Behavioral and brain pattern differences between acting and observing in an auditory task

    Directory of Open Access Journals (Sweden)

    Ventouras Errikos M


    Full Text Available Abstract Background Recent research has shown that errors seem to influence the patterns of brain activity. Additionally current notions support the idea that similar brain mechanisms are activated during acting and observing. The aim of the present study was to examine the patterns of brain activity of actors and observers elicited upon receiving feedback information of the actor's response. Methods The task used in the present research was an auditory identification task that included both acting and observing settings, ensuring concurrent ERP measurements of both participants. The performance of the participants was investigated in conditions of varying complexity. ERP data were analyzed with regards to the conditions of acting and observing in conjunction to correct and erroneous responses. Results The obtained results showed that the complexity induced by cue dissimilarity between trials was a demodulating factor leading to poorer performance. The electrophysiological results suggest that feedback information results in different intensities of the ERP patterns of observers and actors depending on whether the actor had made an error or not. The LORETA source localization method yielded significantly larger electrical activity in the supplementary motor area (Brodmann area 6, the posterior cingulate gyrus (Brodmann area 31/23 and the parietal lobe (Precuneus/Brodmann area 7/5. Conclusion These findings suggest that feedback information has a different effect on the intensities of the ERP patterns of actors and observers depending on whether the actor committed an error. Certain neural systems, including medial frontal area, posterior cingulate gyrus and precuneus may mediate these modulating effects. Further research is needed to elucidate in more detail the neuroanatomical and neuropsychological substrates of these systems.

  1. Timing of developmental sequences in different brain structures: physiological and pathological implications. (United States)

    Dehorter, N; Vinay, L; Hammond, C; Ben-Ari, Y


    The developing brain is not a small adult brain. Voltage- and transmitter-gated currents, like network-driven patterns, follow a developmental sequence. Studies initially performed in cortical structures and subsequently in subcortical structures have unravelled a developmental sequence of events in which intrinsic voltage-gated calcium currents are followed by nonsynaptic calcium plateaux and synapse-driven giant depolarising potentials, orchestrated by depolarizing actions of GABA and long-lasting NMDA receptor-mediated currents. The function of these early patterns is to enable heterogeneous neurons to fire and wire together rather than to code specific modalities. However, at some stage, behaviourally relevant activities must replace these immature patterns, implying the presence of programmed stop signals. Here, we show that the developing striatum follows a developmental sequence in which immature patterns are silenced precisely when the pup starts locomotion. This is mediated by a loss of the long-lasting NMDA-NR2C/D receptor-mediated current and the expression of a voltage-gated K(+) current. At the same time, the descending inputs to the spinal cord become fully functional, accompanying a GABA/glycine polarity shift and ending the expression of developmental patterns. Therefore, although the timetable of development differs in different brain structures, the g sequence is quite similar, relying first on nonsynaptic events and then on synaptic oscillations that entrain large neuronal populations. In keeping with the 'neuroarcheology' theory, genetic mutations or environmental insults that perturb these developmental sequences constitute early signatures of developmental disorders. Birth dating developmental disorders thus provides important indicators of the event that triggers the pathological cascade leading ultimately to disease.

  2. Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia.

    Directory of Open Access Journals (Sweden)

    Carolyn D Langen

    Full Text Available Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, "bi-modal comparison plots" show the distribution of uni- and bi-modal group differences and the relationship between structure and function. Differences between brain lobes are visualized using "worm plots". Group differences in connections are examined with an existing visualization, the "connectogram". These visualizations were evaluated in two proof-of-concept studies: (1 middle-aged versus elderly subjects; and (2 patients with schizophrenia versus controls. Each included two measures derived from diffusion weighted images and two from functional magnetic resonance images. The structural measures were minimum cost path between two anatomical regions according to the "Statistical Analysis of Minimum cost path based Structural Connectivity" method and the average fractional anisotropy along the fiber. The functional measures were Pearson's correlation and partial correlation of mean regional time series. The relationship between structure and function was similar in both studies. Uni-modal group differences varied greatly between connectivity types. Group differences were identified in both studies globally, within brain lobes and between regions. In the aging study, minimum cost path was highly effective in identifying group differences on all levels; fractional anisotropy and mean correlation showed smaller differences on the brain lobe and regional levels. In the schizophrenia study, minimum cost path and fractional anisotropy showed differences on the global level and within brain lobes; mean correlation showed small differences on the lobe level. Only

  3. Western Hemisphere Defense Policy Statement (United States)


    El Salvador, Guatemala, Honduras , Paraguay, Peru and Uruguay have contributed to or led multi-national security operations and United Nations (UN...impact on regional and global peace and security and reflect the new realities of defense cooperation in the hemisphere. Working with Canada and...Mexico, DoD remains prepared to deter and defeat direct threats to our homeland. We partner with Canada on regional security issues such as an evolving

  4. The Effect of Playing Different Musical Instruments on Arm Asymmetry (United States)

    Kaya, E. Erdem


    Between the two hemispheres of the brain, structural and functional differences are called cerebral lateralization that can affect the skill performance of both arms in a different way, which is called handedness. Approximately 90% of people are right-handed and they use the right hand for most skillful activities. Interestingly, recent studies…

  5. Hemispheric Laterality in Music and Math (United States)

    Szirony, Gary Michael; Burgin, John S.; Pearson, L. Carolyn


    Hemispheric laterality may be a useful concept in teaching, learning, training, and in understanding more about human development. To address this issue, a measure of hemispheric laterality was compared to musical and mathematical ability. The Human Information Processing Survey (HIPS) instrument, designed to measure hemispheric laterality, was…

  6. Regional differences in gene expression and promoter usage in aged human brains

    KAUST Repository

    Pardo, Luba M.


    To characterize the promoterome of caudate and putamen regions (striatum), frontal and temporal cortices, and hippocampi from aged human brains, we used high-throughput cap analysis of gene expression to profile the transcription start sites and to quantify the differences in gene expression across the 5 brain regions. We also analyzed the extent to which methylation influenced the observed expression profiles. We sequenced more than 71 million cap analysis of gene expression tags corresponding to 70,202 promoter regions and 16,888 genes. More than 7000 transcripts were differentially expressed, mainly because of differential alternative promoter usage. Unexpectedly, 7% of differentially expressed genes were neurodevelopmental transcription factors. Functional pathway analysis on the differentially expressed genes revealed an overrepresentation of several signaling pathways (e.g., fibroblast growth factor and wnt signaling) in hippocampus and striatum. We also found that although 73% of methylation signals mapped within genes, the influence of methylation on the expression profile was small. Our study underscores alternative promoter usage as an important mechanism for determining the regional differences in gene expression at old age.

  7. Different brain structures associated with artistic and scientific creativity: a voxel-based morphometry study (United States)

    Shi, Baoguo; Cao, Xiaoqing; Chen, Qunlin; Zhuang, Kaixiang; Qiu, Jiang


    Creativity is the ability to produce original and valuable ideas or behaviors. In real life, artistic and scientific creativity promoted the development of human civilization; however, to date, no studies have systematically investigated differences in the brain structures responsible for artistic and scientific creativity in a large sample. Using voxel-based morphometry (VBM), this study identified differences in regional gray matter volume (GMV) across the brain between artistic and scientific creativity (assessed by the Creative Achievement Questionnaire) in 356 young, healthy subjects. The results showed that artistic creativity was significantly negatively associated with the regional GMV of the supplementary motor area (SMA) and anterior cingulate cortex (ACC). In contrast, scientific creativity was significantly positively correlated with the regional GMV of the left middle frontal gyrus (MFG) and left inferior occipital gyrus (IOG). Overall, artistic creativity was associated with the salience network (SN), whereas scientific creativity was associated with the executive attention network and semantic processing. These results may provide an effective marker that can be used to predict and evaluate individuals’ creative performance in the fields of science and art. PMID:28220826

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

  9. The brain functional networks associated to human and animal suffering differ among omnivores, vegetarians and vegans. (United States)

    Filippi, Massimo; Riccitelli, Gianna; Falini, Andrea; Di Salle, Francesco; Vuilleumier, Patrik; Comi, Giancarlo; Rocca, Maria A


    Empathy and affective appraisals for conspecifics are among the hallmarks of social interaction. Using functional MRI, we hypothesized that vegetarians and vegans, who made their feeding choice for ethical reasons, might show brain responses to conditions of suffering involving humans or animals different from omnivores. We recruited 20 omnivore subjects, 19 vegetarians, and 21 vegans. The groups were matched for sex and age. Brain activation was investigated using fMRI and an event-related design during observation of negative affective pictures of human beings and animals (showing mutilations, murdered people, human/animal threat, tortures, wounds, etc.). Participants saw negative-valence scenes related to humans and animals, alternating with natural landscapes. During human negative valence scenes, compared with omnivores, vegetarians and vegans had an increased recruitment of the anterior cingulate cortex (ACC) and inferior frontal gyrus (IFG). More critically, during animal negative valence scenes, they had decreased amygdala activation and increased activation of the lingual gyri, the left cuneus, the posterior cingulate cortex and several areas mainly located in the frontal lobes, including the ACC, the IFG and the middle frontal gyrus. Nonetheless, also substantial differences between vegetarians and vegans have been found responding to negative scenes. Vegetarians showed a selective recruitment of the right inferior parietal lobule during human negative scenes, and a prevailing activation of the ACC during animal negative scenes. Conversely, during animal negative scenes an increased activation of the inferior prefrontal cortex was observed in vegans. These results suggest that empathy toward non conspecifics has different neural representation among individuals with different feeding habits, perhaps reflecting different motivational factors and beliefs.

  10. Short and Long-Term Analysis and Comparison of Neurodegeneration and Inflammatory Cell Response in the Ipsilateral and Contralateral Hemisphere of the Neonatal Mouse Brain after Hypoxia/Ischemia

    Directory of Open Access Journals (Sweden)

    Kalpana Shrivastava


    Full Text Available Understanding the evolution of neonatal hypoxic/ischemic is essential for novel neuroprotective approaches. We describe the neuropathology and glial/inflammatory response, from 3 hours to 100 days, after carotid occlusion and hypoxia (8% O2, 55 minutes to the C57/BL6 P7 mouse. Massive tissue injury and atrophy in the ipsilateral (IL hippocampus, corpus callosum, and caudate-putamen are consistently shown. Astrogliosis peaks at 14 days, but glial scar is still evident at day 100. Microgliosis peaks at 3–7 days and decreases by day 14. Both glial responses start at 3 hours in the corpus callosum and hippocampal fissure, to progressively cover the degenerating CA field. Neutrophils increase in the ventricles and hippocampal vasculature, showing also parenchymal extravasation at 7 days. Remarkably, delayed milder atrophy is also seen in the contralateral (CL hippocampus and corpus callosum, areas showing astrogliosis and microgliosis during the first 72 hours. This detailed and long-term cellular response characterization of the ipsilateral and contralateral hemisphere after H/I may help in the design of better therapeutic strategies.

  11. Phenological changes in the southern hemisphere.

    Directory of Open Access Journals (Sweden)

    Lynda E Chambers

    Full Text Available Current evidence of phenological responses to recent climate change is substantially biased towards northern hemisphere temperate regions. Given regional differences in climate change, shifts in phenology will not be uniform across the globe, and conclusions drawn from temperate systems in the northern hemisphere might not be applicable to other regions on the planet. We conduct the largest meta-analysis to date of phenological drivers and trends among southern hemisphere species, assessing 1208 long-term datasets from 89 studies on 347 species. Data were mostly from Australasia (Australia and New Zealand, South America and the Antarctic/subantarctic, and focused primarily on plants and birds. This meta-analysis shows an advance in the timing of spring events (with a strong Australian data bias, although substantial differences in trends were apparent among taxonomic groups and regions. When only statistically significant trends were considered, 82% of terrestrial datasets and 42% of marine datasets demonstrated an advance in phenology. Temperature was most frequently identified as the primary driver of phenological changes; however, in many studies it was the only climate variable considered. When precipitation was examined, it often played a key role but, in contrast with temperature, the direction of phenological shifts in response to precipitation variation was difficult to predict a priori. We discuss how phenological information can inform the adaptive capacity of species, their resilience, and constraints on autonomous adaptation. We also highlight serious weaknesses in past and current data collection and analyses at large regional scales (with very few studies in the tropics or from Africa and dramatic taxonomic biases. If accurate predictions regarding the general effects of climate change on the biology of organisms are to be made, data collection policies focussing on targeting data-deficient regions and taxa need to be financially

  12. Intrinsic Brain Activity Responsible for Sex Differences in Shyness and Social Anxiety (United States)

    Yang, Xun; Zhou, Ming; Lama, Sunima; Chen, Lizhou; Hu, Xinyu; Wang, Song; Chen, Taolin; Shi, Yan; Huang, Xiaoqi; Gong, Qiyong


    Male and female show significant differences in important behavioral features such as shyness, yet the neural substrates of these differences remain poorly understood. Previous neuroimaging studies have demonstrated that both shyness and social anxiety in healthy subjects are associated with increased activation in the fronto-limbic and cognitive control areas. However, it remains unknown whether these brain abnormalities would be shared by different genders. Therefore, in the current study, we used resting-state fMRI (r-fMRI) to investigate sex differences in intrinsic cerebral activity that may contribute to shyness and social anxiety. Sixty subjects (28 males, 32 females) participated in r-fMRI scans, and the amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF) were used to measure the spontaneous regional cerebral activity in all subjects. We first compared the differences between male and female both in the ALFF and fALFF and then we also examined the whole brain correlation between the ALFF/fALFF and the severity of shyness as well as social anxiety by genders. Referring to shyness measure, we found a significant positive correlation between shyness scores (CBSS) and ALFF/fALFF value in the frontoparietal control network and a negative correlation in the cingulo-insular network in female; while in male, there is no such correlation. For the social anxiety level, we found positive correlations between Leibowitz Social Anxiety Scale (LSAS) scores and spontaneous activity in the frontal-limbic network in male and negative correlation between the frontal-parietal network; however, such correlation was not prominent in female. This pattern suggests that shy female individuals engaged a proactive control process, driven by a positive association with activity in frontoparietal network and negative association in cingulo-insular network, whereas social anxiety males relied more on a reactive control process, driven by a positive correlation of

  13. rTMS of the unaffected hemisphere transiently reduces contralesional visuospatial hemineglect. (United States)

    Oliveri, M; Bisiach, E; Brighina, F; Piazza, A; La Bua, V; Buffa, D; Fierro, B


    To verify the role of interhemispheric influences on manifestations of neglect, the authors investigated the effects of a transient repetitive transcranial magnetic stimulation (rTMS)-induced disruption of the unaffected hemisphere on contralesional visuospatial neglect in two left- and five right-brain-damaged patients. Parietal rTMS of the unaffected hemisphere during the execution of a computerized task of bisected line's length judgment transiently decreased the magnitude of neglect as expressed in the number of errors.

  14. Brain regional differences in CB1 receptor adaptation and regulation of transcription. (United States)

    Lazenka, M F; Selley, D E; Sim-Selley, L J


    Cannabinoid CB1 receptors (CB1Rs) are expressed throughout the brain and mediate the central effects of cannabinoids, including Δ(9)-tetrahydrocannabinol (THC), the main psychoactive constituent of marijuana. Repeated THC administration produces tolerance to cannabinoid-mediated effects, although the magnitude of tolerance varies by effect. Consistent with this observation, CB1R desensitization and downregulation, as well as induction of immediate early genes (IEGs), vary by brain region. Zif268 and c-Fos are induced in the forebrain after acute THC administration. Phosphorylation of the cAMP response-element binding protein (CREB) is increased in a region-specific manner after THC administration. Results differ between acute versus repeated THC injection, and suggest that tolerance to IEG activation might develop in some regions. Repeated THC treatment produces CB1R desensitization and downregulation in the brain, although less adaption occurs in the striatum as compared to regions such as the hippocampus. Repeated THC treatment also induces expression of ΔFosB, a very stable isoform of FosB, in the striatum. Transgenic expression of ∆FosB in the striatum enhances the rewarding effects of several drugs, but its role in THC-mediated effects is not known. The inverse regional relationship between CB1R desensitization and ∆FosB induction suggests that these adaptations might inhibit each other, although this possibility has not been investigated. The differential regional expression of individual IEGs by acute or repeated THC administration suggests that regulation of target genes and effects on CB1R signaling will contribute to the behavioral effects of THC.

  15. Subcortical brain volume differences in participants with attention deficit hyperactivity disorder in children and adults

    DEFF Research Database (Denmark)

    Hoogman, Martine; Bralten, Janita; Hibar, Derrek P


    BACKGROUND: Neuroimaging studies have shown structural alterations in several brain regions in children and adults with attention deficit hyperactivity disorder (ADHD). Through the formation of the international ENIGMA ADHD Working Group, we aimed to address weaknesses of previous imaging studies...... compared with controls in the mega-analysis. There was no difference in volume size in the pallidum (p=0·95) and thalamus (p=0·39) between people with ADHD and controls. Exploratory lifespan modelling suggested a delay of maturation and a delay of degeneration, as effect sizes were highest in most...... and adults for the pallidum (p=0·79) or thalamus (p=0·89). Case-control differences in adults were non-significant (all p>0·03). Psychostimulant medication use (all p>0·15) or symptom scores (all p>0·02) did not influence results, nor did the presence of comorbid psychiatric disorders (all p>0...

  16. A tensor-based morphometry analysis of regional differences in brain volume in relation to prenatal alcohol exposure

    Directory of Open Access Journals (Sweden)

    E.M. Meintjes


    Full Text Available Reductions in brain volumes represent a neurobiological signature of fetal alcohol spectrum disorders (FASD. Less clear is how regional brain tissue reductions differ after normalizing for brain size differences linked with FASD and whether these profiles can predict the degree of prenatal exposure to alcohol. To examine associations of regional brain tissue excesses/deficits with degree of prenatal alcohol exposure and diagnosis with and without correction for overall brain volume, tensor-based morphometry (TBM methods were applied to structural imaging data from a well-characterized, demographically homogeneous sample of children diagnosed with FASD (n = 39, 9.6–11.0 years and controls (n = 16, 9.5–11.0 years. Degree of prenatal alcohol exposure was significantly associated with regionally pervasive brain tissue reductions in: (1 the thalamus, midbrain, and ventromedial frontal lobe, (2 the superior cerebellum and inferior occipital lobe, (3 the dorsolateral frontal cortex, and (4 the precuneus and superior parietal lobule. When overall brain size was factored out of the analysis on a subject-by-subject basis, no regions showed significant associations with alcohol exposure. FASD diagnosis was associated with a similar deformation pattern, but few of the regions survived FDR correction. In data-driven independent component analyses (ICA regional brain tissue deformations successfully distinguished individuals based on extent of prenatal alcohol exposure and to a lesser degree, diagnosis. The greater sensitivity of the continuous measure of alcohol exposure compared with the categorical diagnosis across diverse brain regions underscores the dose dependence of these effects. The ICA results illustrate that profiles of brain tissue alterations may be a useful indicator of prenatal alcohol exposure when reliable historical data are not available and facial features are not apparent.

  17. Cross-hemispheric collaboration and segregation associated with task difficulty as revealed by structural and functional connectivity. (United States)

    Davis, Simon W; Cabeza, Roberto


    Although it is known that brain regions in one hemisphere may interact very closely with their corresponding contralateral regions (collaboration) or operate relatively independent of them (segregation), the specific brain regions (where) and conditions (how) associated with collaboration or segregation are largely unknown. We investigated these issues using a split field-matching task in which participants matched the meaning of words or the visual features of faces presented to the same (unilateral) or to different (bilateral) visual fields. Matching difficulty was manipulated by varying the semantic similarity of words or the visual similarity of faces. We assessed the white matter using the fractional anisotropy (FA) measure provided by diffusion tensor imaging (DTI) and cross-hemispheric communication in terms of fMRI-based connectivity between homotopic pairs of cortical regions. For both perceptual and semantic matching, bilateral trials became faster than unilateral trials as difficulty increased (bilateral processing advantage, BPA). The study yielded three novel findings. First, whereas FA in anterior corpus callosum (genu) correlated with word-matching BPA, FA in posterior corpus callosum (splenium-occipital) correlated with face-matching BPA. Second, as matching difficulty intensified, cross-hemispheric functional connectivity (CFC) increased in domain-general frontopolar cortex (for both word and face matching) but decreased in domain-specific ventral temporal lobe regions (temporal pole for word matching and fusiform gyrus for face matching). Last, a mediation analysis linking DTI and fMRI data showed that CFC mediated the effect of callosal FA on BPA. These findings clarify the mechanisms by which the hemispheres interact to perform complex cognitive tasks.

  18. Anosognosia in patients with acute hemispheric ischemic stroke

    Directory of Open Access Journals (Sweden)

    V. N. Grigoryeva


    Full Text Available Objective: to investigate the frequency of anosognosia (a deficit of self-awareness, its anatomic correlates associated with other neuropsychological and neurological disorders in acute hemispheric ischemic stroke (IS.Patients and methods 150 patients (83 men and 67 women; mean age, 63.0±9.3 years with acute hemispheric IS were examined. All the patients underwent neurological, neuroimaging, and neuropsychological (by the procedure described by A.R. Luria examinations. neuropsychological investigations. Anosognosia was diagnosed using the Dysexecutive Questionnaire (DEX and the authors' procedure involving a scale to measure impaired self-rating of motor abilities and a scale to measure impaired self-rating of cognitive abilities in everyday life.Results and discussion. In the acute period of hemispheric IS, reduced self-awareness of motor and cognitive abilities was noted in 14% of the patients and unawareness of only cognitive abilities was recorded in 15%. Patients with anosognosia and cognitive dysfunction (ACD and those with anosognosia and motor dysfunction (AMD had right-sided hemispheric IS more frequently (76% while this was not found in patients with isolated ACD. The development of anosognosia for paralysis and paresis was favored by the large sizes of an ischemic focus that involved a few lobes in the posterior regions of the brain although no lesions were found in the anosognosia-specific anatomical regions. ACD and AMD proved to be associated with unilateral spatial and tactile neglect and obvious regulatory dysfunction. 

  19. Mercury distribution and speciation in different brain regions of beluga whales (Delphinapterus leucas)

    Energy Technology Data Exchange (ETDEWEB)

    Ostertag, Sonja K., E-mail: [Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, British Columbia, V2N 4Z9 (Canada); Stern, Gary A., E-mail: [Freshwater Institute, Fisheries and Oceans Canada, Winnipeg, Manitoba, R3T 2N6 (Canada); Centre for Earth Observation Science, Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada); Wang, Feiyue, E-mail: [Centre for Earth Observation Science, Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada); Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada); Lemes, Marcos, E-mail: [Centre for Earth Observation Science, Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada); Chan, Hing Man, E-mail: [Center for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, 1N 6N5 (Canada)


    The toxicokinetics of mercury (Hg) in key species of Arctic ecosystem are poorly understood. We sampled five brain regions (frontal lobe, temporal lobe, cerebellum, brain stem and spinal cord) from beluga whales (Delphinapterus leucas) harvested in 2006, 2008, and 2010 from the eastern Beaufort Sea, Canada, and measured total Hg (HgT) and total selenium (SeT) by inductively coupled plasma mass spectrometry (ICP-MS), mercury analyzer or cold vapor atomic absorption spectrometry, and the chemical forms using a high performance liquid chromatography ICP-MS. At least 14% of the beluga whales had HgT concentrations higher than the levels of observable adverse effect (6.0 mg kg{sup −1} wet weight (ww)) in primates. The concentrations of HgT differed between brain regions; median concentrations (mg kg{sup −1} ww) were 2.34 (0.06 to 22.6, 81) (range, n) in temporal lobe, 1.84 (0.12 to 21.9, 77) in frontal lobe, 1.84 (0.05 to 16.9, 83) in cerebellum, 1.25 (0.02 to 11.1, 77) in spinal cord and 1.32 (0.13 to 15.2, 39) in brain stem. Total Hg concentrations in the cerebellum increased with age (p < 0.05). Between 35 and 45% of HgT was water-soluble, of which, 32 to 41% was methyl mercury (MeHg) and 59 to 68% was labile inorganic Hg. The concentration of MeHg (range: 0.03 to 1.05 mg kg{sup −1} ww) was positively associated with HgT concentration, and the percent MeHg (4 to 109%) decreased exponentially with increasing HgT concentration in the spinal cord, cerebellum, frontal lobe and temporal lobe. There was a positive association between SeT and HgT in all brain regions (p < 0.05) suggesting that Se may play a role in the detoxification of Hg in the brain. The concentration of HgT in the cerebellum was significantly associated with HgT in other organs. Therefore, HgT concentrations in organs that are frequently sampled in bio-monitoring studies could be used to estimate HgT concentrations in the cerebellum, which is the target organ of MeHg toxicity. - Highlights:

  20. The brain adjusts grip forces differently according to gravity and inertia: a parabolic flight experiment. (United States)

    White, Olivier


    In everyday life, one of the most frequent activities involves accelerating and decelerating an object held in precision grip. In many contexts, humans scale and synchronize their grip force (GF), normal to the finger/object contact, in anticipation of the expected tangential load force (LF), resulting from the combination of the gravitational and the inertial forces. In many contexts, GF and LF are linearly coupled. A few studies have examined how we adjust the parameters-gain and offset-of this linear relationship. However, the question remains open as to how the brain adjusts GF regardless of whether LF is generated by different combinations of weight and inertia. Here, we designed conditions to generate equivalent magnitudes of LF by independently varying mass and movement frequency. In a control experiment, we directly manipulated gravity in parabolic flights, while other factors remained constant. We show with a simple computational approach that, to adjust GF, the brain is sensitive to how LFs are produced at the fingertips. This provides clear evidence that the analysis of the origin of LF is performed centrally, and not only at the periphery.

  1. Duration of exclusive breastfeeding is associated with differences in infants' brain responses to emotional body expressions. (United States)

    Krol, Kathleen M; Rajhans, Purva; Missana, Manuela; Grossmann, Tobias


    Much research has recognized the general importance of maternal behavior in the early development and programing of the mammalian offspring's brain. Exclusive breastfeeding (EBF) duration, the amount of time in which breastfed meals are the only source of sustenance, plays a prominent role in promoting healthy brain and cognitive development in human children. However, surprisingly little is known about the influence of breastfeeding on social and emotional development in infancy. In the current study, we examined whether and how the duration of EBF impacts the neural processing of emotional signals by measuring electro-cortical responses to body expressions in 8-month-old infants. Our analyses revealed that infants with high EBF experience show a significantly greater neural sensitivity to happy body expressions than those with low EBF experience. Moreover, regression analyses revealed that the neural bias toward happiness or fearfulness differs as a function of the duration of EBF. Specifically, longer breastfeeding duration is associated with a happy bias, whereas shorter breastfeeding duration is associated with a fear bias. These findings suggest that breastfeeding experience can shape the way in which infants respond to emotional signals.

  2. Diffusion tensor imaging differences relate to memory deficits in diffuse traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Roig Teresa


    Full Text Available Abstract Background Memory is one of the most impaired functions after traumatic brain injury (TBI. We used diffusion tensor imaging (DTI to determine the structural basis of memory deficit. We correlated fractional anisotropy (FA of the fasciculi connecting the main cerebral regions that are involved in declarative and working memory functions. Methods Fifteen patients with severe and diffuse TBI and sixteen healthy controls matched by age and years of education were scanned. The neuropsychological assessment included: Letter-number sequencing test (LNS, 2-back task, digit span (forwards and backwards and the Rivermead profilet. DTI was analyzed by a tract-based spatial statics (TBSS approach. Results Whole brain DTI analysis showed a global decrease in FA values that correlated with the 2-back d-prime index, but not with the Rivermead profile. ROI analysis revealed positive correlations between working memory performance assessed by 2-back d-prime and superior longitudinal fasciculi, corpus callosum, arcuate fasciculi and fornix. Declarative memory assessed by the Rivermead profile scores correlated with the fornix and the corpus callosum. Conclusions Diffuse TBI is associated with a general decrease of white matter integrity. Nevertheless deficits in specific memory domains are related to different patterns of white matter damage.

  3. Brains of verbal memory specialists show anatomical differences in language, memory and visual systems. (United States)

    Hartzell, James F; Davis, Ben; Melcher, David; Miceli, Gabriele; Jovicich, Jorge; Nath, Tanmay; Singh, Nandini Chatterjee; Hasson, Uri


    We studied a group of verbal memory specialists to determine whether intensive oral text memory is associated with structural features of hippocampal and lateral-temporal regions implicated in language processing. Professional Vedic Sanskrit Pandits in India train from childhood for around 10years in an ancient, formalized tradition of oral Sanskrit text memorization and recitation, mastering the exact pronunciation and invariant content of multiple 40,000-100,000 word oral texts. We conducted structural analysis of gray matter density, cortical thickness, local gyrification, and white matter structure, relative to matched controls. We found massive gray matter density and cortical thickness increases in Pandit brains in language, memory and visual systems, including i) bilateral lateral temporal cortices and ii) the anterior cingulate cortex and the hippocampus, regions associated with long and short-term memory. Differences in hippocampal morphometry matched those previously documented for expert spatial navigators and individuals with good verbal working memory. The findings provide unique insight into the brain organization implementing formalized oral knowledge systems.

  4. Evaluation method for in situ electric field in standardized human brain for different transcranial magnetic stimulation coils (United States)

    Iwahashi, Masahiro; Gomez-Tames, Jose; Laakso, Ilkka; Hirata, Akimasa


    This study proposes a method to evaluate the electric field induced in the brain by transcranial magnetic stimulation (TMS) to realize focal stimulation in the target area considering the inter-subject difference of the brain anatomy. The TMS is a non-invasive technique used for treatment/diagnosis, and it works by inducing an electric field in a specific area of the brain via a coil-induced magnetic field. Recent studies that report on the electric field distribution in the brain induced by TMS coils have been limited to simplified human brain models or a small number of detailed human brain models. Until now, no method has been developed that appropriately evaluates the coil performance for a group of subjects. In this study, we first compare the magnetic field and the magnetic vector potential distributions to determine if they can be used as predictors of the TMS focality derived from the electric field distribution. Next, the hotspots of the electric field on the brain surface of ten subjects using six coils are compared. Further, decisive physical factors affecting the focality of the induced electric field by different coils are discussed by registering the computed electric field in a standard brain space for the first time, so as to evaluate coil characteristics for a large population of subjects. The computational results suggest that the induced electric field in the target area cannot be generalized without considering the morphological variability of the human brain. Moreover, there was no remarkable difference between the various coils, although focality could be improved to a certain extent by modifying the coil design (e.g., coil radius). Finally, the focality estimated by the electric field was more correlated with the magnetic vector potential than the magnetic field in a homogeneous sphere.

  5. Measurement of blood-brain barrier permeability with t1-weighted dynamic contrast-enhanced MRI in brain tumors: a comparative study with two different algorithms. (United States)

    Bergamino, Maurizio; Saitta, Laura; Barletta, Laura; Bonzano, Laura; Mancardi, Giovanni Luigi; Castellan, Lucio; Ravetti, Jean Louis; Roccatagliata, Luca


    The purpose of this study was to assess the feasibility of measuring different permeability parameters with T1-weighted dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in order to investigate the blood brain-barrier permeability associated with different brain tumors. The Patlak algorithm and the extended Tofts-Kety model were used to this aim. Twenty-five adult patients with tumors of different histological grades were enrolled in this study. MRI examinations were performed at 1.5 T. Multiflip angle, fast low-angle shot, and axial 3D T1-weighted images were acquired to calculate T1 maps, followed by a DCE acquisition. A region of interest was placed within the tumor of each patient to calculate the mean value of different permeability parameters. Differences in permeability measurements were found between different tumor grades, with higher histological grades characterized by higher permeability values. A significant difference in transfer constant (K (trans)) values was found between the two methods on high-grade tumors; however, both techniques revealed a significant correlation between the histological grade of tumors and their K (trans) values. Our results suggest that DCE acquisition is feasible in patients with brain tumors and that K (trans) maps can be easily obtained by these two algorithms, even if the theoretical model adopted could affect the final results.

  6. Neuropsychiatric aspects of severe brain injuries

    Directory of Open Access Journals (Sweden)

    O. S. Zaitsev


    Full Text Available The state-of-the-art of Russian neuropsychiatry and priority developments in different psychopathological syndromes in severe brain injuries are assessed. Many cognitive and emotional impairments are explained in terms of the idea on the organization of psychic activity over time. It is emphasized that to achieve the premorbid levels of an interhemispheric interaction and functional asymmetry of the cerebral hemispheres affords psychic activity recovery. The experience in investigating, classifying, and treating various mental disorders occurring after severe brain injuries is generalized. The basic principles of psychopharmacotherapy and rehabilitation of victims are stated.

  7. Inter-hemispheric asymmetry of Pedersen conductance (United States)

    Deng, Y.; Lu, Y.; Sheng, C.; Yue, X.


    Ionospheric conductance is very important to the magnetosphere-ionosphere coupling in the high latitude region, since it connects the polar cap potential with the currents. Meanwhile, the altitudinal distribution of Pederson conductance gives us a rough idea about the altitudinal distribution of Joule heating at high latitudes. Based on the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites observations of electron density profiles from 2009-2014, Pedersen conductivity has been calculated. A climatologic study of the height-integrated Pedersen conductivities in both E (100-150 km) and F (150-600 km) regions and their ratio in different seasons, solar and geomagnetic conditions have been conducted. A significant inter-hemispheric asymmetry is identified in the seasonal variation. Meanwhile, the conductance in both regions and the conductance ratio show a strong dependence on F10.7 and Ap indices. This result will strongly help our understanding of the inter-hemispheric difference in the high-latitude electrodynamics.

  8. The role of different cues in the brain mechanism on visual spatial attention

    Institute of Scientific and Technical Information of China (English)

    SONG Weiqun; LUO Yuejia; CHI Song; JI Xunming; LING Feng; ZHAO Lun; WANG Maobin; SHI Jiannong


    The visual spatial attention mechanism in the brain was studied in 16 young subjects through the visual search paradigm of precue-target by the event-related potential (ERP) technique, with the attentive ranges cued by different scales of Chinese character and region cues. The results showed that the response time for Chinese character cues was much longer than that for region cues especially for small region cues. With the exterior interferences, the target stimuli recognition under region cues was much quicker than that under Chinese character cues. Compared with that under region cues, targets under Chinese character cues could lead to increase of the posterior P1,decrease of the N1 and increase of the P2. It should also be noted that the differences between region cues and Chinese character cues were affected by the interference types. Under exterior interferences, no significant difference was found between region cues and Chinese character cues; however, it was not the case under the interior interferences. Considering the difference between the exterior interferences and the interior interferences, we could conclude that with the increase of difficulty in target recognition there was obvious difference in the consumption of anterior frontal resources by target stimuli under the two kinds of cues.

  9. Education Quality, Reading Recognition, and Racial Differences in the Neuropsychological Outcome from Traumatic Brain Injury (United States)

    Silverberg, Noah D.; Hanks, Robin A.; Tompkins, Season C.


    Ethnically diverse examinees tend to perform lower on neuropsychological tests. The practice of adjusting normative comparisons for the education level and/or race to prevent overpathologizing low scores is problematic. Education quality, as measured by reading recognition, appears to be a more accurate benchmark for premorbid functioning in certain populations. The present study aimed to extend this line of research to traumatic brain injury (TBI). We hypothesized that a measure of reading recognition, the Wechsler Test of Adult Reading (WTAR), would account for racial differences in neuropsychological performance after TBI. Fifty participants (72% African American, 28% Caucasian) with moderate to severe TBI underwent neuropsychological testing at 1-year post-injury. Reading recognition accounted for all the same variance in neuropsychological performance as race and education (together), as well as considerable additional variance. Estimation of premorbid functioning in African Americans with TBI could be refined by considering reading recognition. PMID:23858087

  10. Postnatal experiences influence how the brain integrates information from different senses

    Directory of Open Access Journals (Sweden)

    Barry E Stein


    Full Text Available Sensory Processing Disorder (SPD is characterized by anomalous reactions to, and integration of, sensory cues. Although the underlying etiology of SPD is unknown, one brain region likely to reflect these sensory and behavioral anomalies is the Superior Colliculus (SC; a structure involved in the synthesis of information from multiple sensory modalities and the control of overt orientation responses. In this review we describe normal functional properties of this structure, the manner in which its individual neurons integrate cues from different senses, and the overt SC-mediated behaviors that are believed to manifest this “multisensory integration.” Of particular interest here is how SC neurons develop their capacity to engage in multisensory integration during early postnatal life as a consequence of early sensory experience, and that it is the intimate communication between cortex and the midbrain makes this developmental process possible.

  11. Beauty and the brain: culture, history and individual differences in aesthetic appreciation. (United States)

    Jacobsen, Thomas


    Human aesthetic processing entails the sensation-based evaluation of an entity with respect to concepts like beauty, harmony or well-formedness. Aesthetic appreciation has many determinants ranging from evolutionary, anatomical or physiological constraints to influences of culture, history and individual differences. There are a vast number of dynamically configured neural networks underlying these multifaceted processes of aesthetic appreciation. In the current challenge of successfully bridging art and science, aesthetics and neuroanatomy, the neuro-cognitive psychology of aesthetics can approach this complex topic using a framework that postulates several perspectives, which are not mutually exclusive. In this empirical approach, objective physiological data from event-related brain potentials and functional magnetic resonance imaging are combined with subjective, individual self-reports.

  12. Serum brain-derived neurotrophic factor levels in different neurological diseases. (United States)

    Ventriglia, Mariacarla; Zanardini, Roberta; Bonomini, Cristina; Zanetti, Orazio; Volpe, Daniele; Pasqualetti, Patrizio; Gennarelli, Massimo; Bocchio-Chiavetto, Luisella


    Consistent evidence indicates the involvement of the brain-derived neurotrophic factor (BDNF) in neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). In the present study, we compared serum BDNF in 624 subjects: 266 patients affected by AD, 28 by frontotemporal dementia (FTD), 40 by Lewy body dementia (LBD), 91 by vascular dementia (VAD), 30 by PD, and 169 controls. Our results evidenced lower BDNF serum levels in AD, FTD, LBD, and VAD patients (P benzodiazepines (P = 0.020). In conclusion, our results support the role of BDNF alterations in neurodegenerative mechanisms common to different forms of neurological disorders and underline the importance of including drug treatment in the analyses to avoid confounding effects.

  13. Education quality, reading recognition, and racial differences in the neuropsychological outcome from traumatic brain injury. (United States)

    Silverberg, Noah D; Hanks, Robin A; Tompkins, Season C


    Ethnically diverse examinees tend to perform lower on neuropsychological tests. The practice of adjusting normative comparisons for the education level and/or race to prevent overpathologizing low scores is problematic. Education quality, as measured by reading recognition, appears to be a more accurate benchmark for premorbid functioning in certain populations. The present study aimed to extend this line of research to traumatic brain injury (TBI). We hypothesized that a measure of reading recognition, the Wechsler Test of Adult Reading (WTAR), would account for racial differences in neuropsychological performance after TBI. Fifty participants (72% African American, 28% Caucasian) with moderate to severe TBI underwent neuropsychological testing at 1-year post-injury. Reading recognition accounted for all the same variance in neuropsychological performance as race and education (together), as well as considerable additional variance. Estimation of premorbid functioning in African Americans with TBI could be refined by considering reading recognition.




    This article shows that the peculiarities of divergent and convergent thinking in young males and females of various creativity levels are stipulated by a definite EEG frequency-and-spa-tial arrangement. Young males and females of mixed and left lateral arrangement profiles demonstrate an expressed activity of occipital, central, and temporal areas of both cerebral hemispheres. In young males and females of right LAP (lateral arrangement profile), connections are clearly localized in case of ...

  15. Gene Regulatory Network Analysis Reveals Differences in Site-specific Cell Fate Determination in Mammalian Brain

    Directory of Open Access Journals (Sweden)

    Gokhan eErtaylan


    Full Text Available Neurogenesis - the generation of new neurons - is an ongoing process that persists in the adult mammalian brain of several species, including humans. In this work we analyze two discrete brain regions: the subventricular zone (SVZ lining the walls of the lateral ventricles; and the subgranular zone (SGZ of the dentate gyrus of the hippocampus in mice and shed light on the SVZ and SGZ specific neurogenesis. We propose a computational model that relies on the construction and analysis of region specific gene regulatory networks from the publicly available data on these two regions. Using this model a number of putative factors involved in neuronal stem cell (NSC identity and maintenance were identified. We also demonstrate potential gender and niche-derived differences based on cell surface and nuclear receptors via Ar, Hif1a and Nr3c1.We have also conducted cell fate determinant analysis for SVZ NSC populations to Olfactory Bulb interneurons and SGZ NSC populations to the granule cells of the Granular Cell Layer. We report thirty-one candidate cell fate determinant gene pairs, ready to be validated. We focus on Ar - Pax6 in SVZ and Sox2 - Ncor1 in SGZ. Both pairs are expressed and localized in the suggested anatomical structures as shown by in situ hybridization and found to physically interact.Finally, we conclude that there are fundamental differences between SGZ and SVZ neurogenesis. We argue that these regulatory mechanisms are linked to the observed differential neurogenic potential of these regions. The presence of nuclear and cell surface receptors in the region specific regulatory circuits indicate the significance of niche derived extracellular factors, hormones and region specific factors such as the oxygen sensitivity, dictating SGZ and SVZ specific neurogenesis.

  16. Flavour exposures after conditioned aversion or preference trigger different brain processes in anaesthetised pigs. (United States)

    Gaultier, A; Meunier-Salaün, M C; Malbert, C H; Val-Laillet, D


    We describe the behavioural consequences of conditioned flavour aversion and preference in pigs and have investigated the brain circuits involved in the representation of flavours with different hedonic values. The study was performed on eight 30-kg pigs. (i) Animals were negatively conditioned to an F- flavour added to a meal followed by LiCl intraduodenal (i.d.) injection, and positively conditioned to an F+ flavour added to a meal followed by NaCl i.d. injection. F+ and F- were thyme or cinnamon flavours. After each conditioning, the behavioural activities were recorded; (ii) One and 5 weeks later, animals were subjected to three two-choice food tests to investigate their preferences between F+, F- and a novel flavour (O); and (iii) Anaesthetised animals were subjected to three SPECT brain imaging sessions: control situation (no flavour) and exposure to F+ and to F-. The negative reinforcement induced a physical malaise and visceral illness. After a positive reinforcement, animals showed playing or feeding motivation and quietness. F+ was significantly preferred over O and F-, and O was significantly preferred over F-. Both F- and F+ induced some metabolic differences in neural circuits involved in sensory associative processes, learning and memory, emotions, reward and feeding motivation. Exposure to F+ induced a higher activity in corticolimbic and reward-related areas, while F- induced a deactivation of the basal nuclei and limbic thalamic nuclei. This study reveals the unconscious cognitive dimension evoked by food flavours according to the individual experience, and highlights the importance of the food sensory image on hedonism and anticipatory eating behaviour.

  17. Natural selection constrains personality and brain gene expression differences in Atlantic salmon (Salmo salar). (United States)

    Thörnqvist, Per-Ove; Höglund, Erik; Winberg, Svante


    In stream-spawning salmonid fishes there is a considerable variation in the timing of when fry leave the spawning nests and establish a feeding territory. The timing of emergence from spawning nests appears to be related to behavioural and physiological traits, e.g. early emerging fish are bolder and more aggressive. In the present study, emerging Atlantic salmon (Salmo salar L.) alevins were sorted into three fractions: early, intermediate and late emerging. At the parr stage, behaviour, stress responses, hindbrain monoaminergic activity and forebrain gene expression were explored in fish from the early and late emerging fractions (first and last 25%). The results show that when subjected to confinement stress, fish from the late emerging fraction respond with a larger activation of the brain serotonergic system than fish from the early fraction. Similarly, in late emerging fish, stress resulted in elevated expression of mRNA coding for serotonin 1A receptors (5-HT1A), GABA-A receptor-associated protein and ependymin, effects not observed in fish from the early emerging fraction. Moreover, fish from the early emerging fraction displayed bolder behaviour than their late emerging littermates. Taken together, these results suggest that time of emergence, boldness and aggression are linked to each other, forming a behavioural syndrome in juvenile salmon. Differences in brain gene expression between early and late emerging salmon add further support to a relationship between stress coping style and timing of emergence. However, early and late emerging salmon do not appear to differ in hypothalamus-pituitary-interrenal (HPI) axis reactivity, another characteristic of divergent stress coping styles.

  18. The diminishing dominance of the dominant hemisphere: Language fMRI in focal epilepsy. (United States)

    Tailby, Chris; Abbott, David F; Jackson, Graeme D


    "Which is the dominant hemisphere?" is a question that arises frequently in patients considered for neurosurgery. The concept of the dominant hemisphere implies uniformity of language lateralisation throughout the brain. It is increasingly recognised that this is not the case in the healthy control brain, and it is especially not so in neurological diseases such as epilepsy. In the present work we adapt our published objective lateralisation method (based on the construction of laterality curves) for use with sub-lobar cortical, subcortical and cerebellar regions of interest (ROIs). We apply this method to investigate regional lateralisation of language activation in 12 healthy controls and 18 focal epilepsy patients, using three different block design language fMRI paradigms, each tapping different aspects of language processing. We compared lateralisation within each ROI across tasks, and investigated how the quantity of data collected affected the ability to robustly estimate laterality across ROIs. In controls, lateralisation was stronger, and the variance across individuals smaller, in cortical ROIs, particularly in the Inferior Frontal (Broca) region. Lateralisation within temporal ROIs was dependent on the nature of the language task employed. One of the healthy controls was left lateralised anteriorly and right lateralised posteriorly. Consistent with previous work, departures from normality occurred in ~ 15-50% of focal epilepsy patients across the different ROIs, with atypicality most common in the Lateral Temporal (Wernicke) region. Across tasks and ROIs the absolute magnitude of the laterality estimate increased and its across participant variance decreased as more cycles of task and rest were included, stabilising at ~ 4 cycles (~ 4 min of data collection). Our data highlight the importance of considering language as a complex task where lateralisation varies at the subhemispheric scale. This is especially important for presurgical planning for

  19. Partition of bispyridinium oximes (trimedoxime and K074) administered in therapeutic doses into different parts of the rat brain. (United States)

    Karasova, Jana Zdarova; Zemek, Filip; Bajgar, Jiri; Vasatova, Martina; Prochazka, Petr; Novotny, Ladislav; Kuca, Kamil


    The penetration of acetylcholinesterase reactivators (oximes) into the central nervous system is typically restricted by the blood-brain barrier. Although oximes are highly hydrophilic compounds, some contradictory results confirming permeation into the brain exist. The aim of this study is to verify the penetration of oximes through the blood-brain barrier and to detect their levels achieved in different brain regions 60 min after the administration. It was confirmed that oximes are able to penetrate into the brain after injection of therapeutic doses corresponding with 5% of LD(50). The level in whole brain was 0.58% for trimedoxime and 0.85% for the experimental drug oxime K074 as the percentage of their plasma concentration. The highest concentration was found in frontal cortex (trimedoxime 2.27%; oxime K074 0.95%) and lowest in basal ganglia (trimedoxime 0.86%; oxime K074 0.42%). Entry of oximes into the brain is minimal, but some low reactivation effect should be expected. The reactivation potency of oximes might be higher or lower, depending on the real oxime concentration in a given area.

  20. Species differences in blood-brain barrier transport of three positron emission tomography radioligands with emphasis on P-glycoprotein transport

    DEFF Research Database (Denmark)

    Syvänen, Stina; Lindhe, Orjan; Palner, Mikael;


    Species differences occur in the brain concentrations of drugs, but the reasons for these differences are not yet apparent. This study was designed to compare brain uptake of three radiolabeled P-glycoprotein (P-gp) substrates across species using positron emission tomography. Brain concentration...

  1. Species differences in blood-brain barrier transport of three positron emission tomography radioligands with emphasis on P-glycoprotein transport

    DEFF Research Database (Denmark)

    Syvanen, S.; Lindhe, O.; Palner, M.;


    Species differences occur in the brain concentrations of drugs, but the reasons for these differences are not yet apparent. This study was designed to compare brain uptake of three radiolabeled P-glycoprotein (P-gp) substrates across species using positron emission tomography. Brain concentrations...

  2. The Hemispheric Sign Rule of Current Helicity during the Rising Phase of Cycle 23

    Indian Academy of Sciences (India)

    S. D. Bao; G. X. Ai; H. Q. Zhang


    We compute the signs of two different current helicity parameters (i.e., best and ) for 87 active regions during the rise of cycle 23. The results indicate that 59% of the active regions in the northern hemisphere have negative best and 65% in the southern hemisphere have positive. This is consistent with that of the cycle 22. However, the helicity parameter shows a weaker opposite hemispheric preference in the new solar cycle. Possible reasons are discussed.

  3. Neuropathological similarities and differences between schizophrenia and bipolar disorder: a flow cytometric postmortem brain study.

    Directory of Open Access Journals (Sweden)

    Yoshitaka Hayashi

    Full Text Available Recent studies suggest that schizophrenia (SCH and bipolar disorder (BPD may share a similar etiopathology. However, their precise neuropathological natures have rarely been characterized in a comprehensive and quantitative fashion. We have recently developed a rapid, quantitative cell-counting method for frozen unfixed postmortem brains using a flow cytometer. In the present study, we not only counted stained nuclei, but also measured their sizes in the gray matter of frontopolar cortices (FPCs and inferior temporal cortices (ITCs from patients with SCH or BPD, as well as in that from normal controls. In terms of NeuN(+ neuronal nuclei size, particularly in the reduced densities of small NeuN(+ nuclei, we found abnormal distributions present in the ITC gray matter of both patient groups. These same abnormalities were also found in the FPCs of SCH patients, whereas in the FPCs of BPD patients, a reduction in oligodendrocyte lineage (olig2(+ cells was much more common. Surprisingly, in the SCH FPC, normal left-greater-than-right asymmetry in neural nuclei densities was almost completely reversed. In the BPD FPC, this asymmetry, though not obvious, differed significantly from that in the SCH FPC. These findings indicate that while similar neuropathological abnormalities are shared by patients with SCH or BPD, differences also exist, mainly in the FPC, which may at least partially explain the differences observed in many aspects in these disorders.

  4. Brain responses to audiovisual speech mismatch in infants are associated with individual differences in looking behaviour. (United States)

    Kushnerenko, Elena; Tomalski, Przemyslaw; Ballieux, Haiko; Ribeiro, Helena; Potton, Anita; Axelsson, Emma L; Murphy, Elizabeth; Moore, Derek G


    Research on audiovisual speech integration has reported high levels of individual variability, especially among young infants. In the present study we tested the hypothesis that this variability results from individual differences in the maturation of audiovisual speech processing during infancy. A developmental shift in selective attention to audiovisual speech has been demonstrated between 6 and 9 months with an increase in the time spent looking to articulating mouths as compared to eyes (Lewkowicz & Hansen-Tift. (2012) Proc. Natl Acad. Sci. USA, 109, 1431-1436; Tomalski et al. (2012) Eur. J. Dev. Psychol., 1-14). In the present study we tested whether these changes in behavioural maturational level are associated with differences in brain responses to audiovisual speech across this age range. We measured high-density event-related potentials (ERPs) in response to videos of audiovisually matching and mismatched syllables /ba/ and /ga/, and subsequently examined visual scanning of the same stimuli with eye-tracking. There were no clear age-specific changes in ERPs, but the amplitude of audiovisual mismatch response (AVMMR) to the combination of visual /ba/ and auditory /ga/ was strongly negatively associated with looking time to the mouth in the same condition. These results have significant implications for our understanding of individual differences in neural signatures of audiovisual speech processing in infants, suggesting that they are not strictly related to chronological age but instead associated with the maturation of looking behaviour, and develop at individual rates in the second half of the first year of life.

  5. Evaluation of different EEG acquisition systems concerning their suitability for building a brain-computer interface

    Directory of Open Access Journals (Sweden)

    Andreas Pinegger


    Full Text Available One important aspect in non-invasive brain-computer interface (BCI research is to acquire the electroencephalogram (EEG in a proper way. From an end-user perspective this means with maximum comfort and without any extra inconveniences (e.g., washing the hair. Whereas from a technical perspective, the signal quality has to be optimal to make the BCI work effectively and efficiently.In this work we evaluated three different commercially available EEG acquisition systems that differ in the type of electrode (gel-, water-, and dry-based, the amplifier technique, and the data transmission method. Every system was tested regarding three different aspects, namely, technical, BCI effectiveness and efficiency (P300 communication and control, and user satisfaction (comfort.We found that the water-based system had the lowest short circuit noise level, the hydrogel-based system had the highest P300 spelling accuracies, and the dry electrode system caused the least inconveniences.Therefore, building a reliable BCI is possible with all evaluated systems and it is on the user to decide which system meets the given requirements best.


    Institute of Scientific and Technical Information of China (English)

    Xu Jin; Li Wenwen; Zheng Chongxun; Jing Guixia; Liu Xueliang


    Objective To detect the change of brain activity under different depth of anesthesia (DOA)noninvasively. Methods The Lempel-Ziv complexity C(n) was used to analyze EEG and its four components (delta,theta, alpha, beta), which was recorded from SD rats under different DOA. The relationship between C(n) and DOA was studied. Results The C(n) of EEG will decrease while the depth of anesthesia increasing and vice versa. It can be used to detect the change of DOA sensitively. Compared with power spectrum, the change of C(n) is opposite to that of power spectru,. Only the C(n) of delta rhythm has obvious variations induced by the change of DOA, and the variations of delta is as similar as the EEG's. Conclusion The study shows that the desynchronized EEG is replaced by the synchronized EEG when rat goes into anesthesia state from awake, that is just the reason why complexity and power spectrum appear corresponding changes under different DOA. C(n) of delta rhythm dynamic change leads to the change of EEG, and the delta rhythm is the dominant rhythm during anesthesia for rats.

  7. Gender differences of brain activity in the conflicts based on implicit self-esteem.

    Directory of Open Access Journals (Sweden)

    Reiko Miyamoto

    Full Text Available There are gender differences in global and domain-specific self-esteem and the incidence of some psychiatric disorders related to self-esteem, suggesting that there are gender differences in the neural basis underlying one's own self-esteem. We investigated gender differences in the brain activity while subjects (14 males and 12 females performed an implicit self-esteem task, using fMRI. While ventromedial prefrontal cortex (vmPFC was significantly activated in females, medial and dorsomedial PFC (dmPFC were activated in males in the incongruent condition (self = negative compared with the congruent condition (self = positive. Additionally, scores on the explicit self-esteem test were negatively correlated with vmPFC activity in females and positively correlated with dmPFC activity in males. Furthermore, the functional relationships among the regions found by direct gender comparisons were discussed based on the somatic-marker model. These showed that, compared to males, females more firmly store even the incongruent associations as part of their schematic self-knowledge, and such associations automatically activate the neural networks for emotional response and control, in which vmPFC plays a central role. This may explain female cognitive/behavioral traits; females have more tendency to ruminate more often than males, which sometimes results in a prolonged negative affect.

  8. The Production of Linguistic Prosodic Structures in Subjects with Right Hemisphere Damage (United States)

    Walker, Judy Perkins; Pelletier, Rebecca; Reif, Lindsay


    This study examined the right hemisphere contribution to the production of linguistic prosody where acoustic features of prosodic structures in different linguistic contexts were examined accompanied by perceptual judgements. When control and right hemisphere damaged (RHD) subjects were asked to produce lexical stress differences (Experiment 1),…

  9. Hemispheric specialization and independence for word recognition: a comparison of three computational models. (United States)

    Weems, Scott A; Reggia, James A


    Two findings serve as the hallmark for hemispheric specialization during lateralized lexical decision. First is an overall word advantage, with words being recognized more quickly and accurately than non-words (the effect being stronger in response latency). Second, a right visual field advantage is observed for words, with little or no hemispheric differences in the ability to identify non-words. Several theories have been proposed to account for this difference in word and non-word recognition, some by suggesting dual routes of lexical access and others by incorporating separate, and potentially independent, word and non-word detection mechanisms. We compare three previously proposed cognitive theories of hemispheric interactions (callosal relay, direct access, and cooperative hemispheres) through neural network modeling, with each network incorporating different means of interhemispheric communication. When parameters were varied to simulate left hemisphere specialization for lexical decision, only the cooperative hemispheres model showed both a consistent left hemisphere advantage for word recognition but not non-word recognition, as well as an overall word advantage. These results support the theory that neural representations of words are more strongly established in the left hemisphere through prior learning, despite open communication between the hemispheres during both learning and recall.

  10. Assessment of murine brain tissue shrinkage caused by different histological fixatives using magnetic resonance and computed tomography imaging. (United States)

    Wehrl, Hans F; Bezrukov, Ilja; Wiehr, Stefan; Lehnhoff, Mareike; Fuchs, Kerstin; Mannheim, Julia G; Quintanilla-Martinez, Leticia; Kohlhofer, Ursula; Kneilling, Manfred; Pichler, Bernd J; Sauter, Alexander W


    Especially for neuroscience and the development of new biomarkers, a direct correlation between in vivo imaging and histology is essential. However, this comparison is hampered by deformation and shrinkage of tissue samples caused by fixation, dehydration and paraffin embedding. We used magnetic resonance (MR) imaging and computed tomography (CT) imaging to analyze the degree of shrinkage on murine brains for various fixatives. After in vivo imaging using 7 T MRI, animals were sacrificed and the brains were dissected and immediately placed in different fixatives, respectively: zinc-based fixative, neutral buffered formalin (NBF), paraformaldehyde (PFA), Bouin-Holland fixative and paraformaldehyde-lysine-periodate (PLP). The degree of shrinkage based on mouse brain volumes, radiodensity in Hounsfield units (HU), as well as non-linear deformations were obtained. The highest degree of shrinkage was observed for PLP (68.1%, P brain shrinkage and only small deformations and is therefore recommended for in vivo ex vivo comparison studies.

  11. Differences in functional brain connectivity alterations associated with cerebral amyloid deposition in amnestic mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Dahyun eYi


    Full Text Available Despite potential implications for the early detection of impending AD, very little is known about the differences of large scale brain networks between amnestic MCI (aMCI with high cerebral amyloid beta protein (Aβ deposition (i.e., aMCI+ and aMCI with no or very little Aβ deposition (i.e., aMCI-. We first aimed to extend the current literature on altering intrinsic functional connectivity (FC of the default mode network (DMN and salience network (SN from CN to AD dementia. Second, we further examined the differences of the DMN and the SN between aMCI-, aMCI+, and CN. Forty-three older adult (12 CN, 10 aMCI+, 10 aMCI-, and 11 AD dementia subjects were included. All participants received clinical and neuropsychological assessment, resting state functional MRI, structural MRI, and Pittsburgh compound-B-PET scans. FC data were preprocessed using Multivariate Exploratory Linear Optimized Decomposition into Independent Components of FSL. Group comparisons were carried out using the dual-regression approach. In addition, to verify presence of grey matter (GM volume changes with intrinsic functional network alterations, Voxel Based Morphometry was performed on the acquired T1-weighted data. As expected, AD dementia participants exhibited decreased FC in the DMN compared to CN (in precuneus and cingulate gyrus. The degree of alteration in the DMN in aMCI+ compared to CN was intermediate to that of AD. In contrast, aMCI- exhibited increased FC in the DMN compared to CN (in precuneus as well as aMCI+. In terms of the SN, aMCI- exhibited decreased FC compared to both CN and aMCI+ particularly in the inferior frontal gyrus. FC within the SN in aMCI+ and AD did not differ from CN. Compared to CN, aMCI- showed atrophy in bilateral superior temporal gyri whereas aMCI+ showed atrophy in right precuneus. The results indicate that despite of the similarity in cross-sectional cognitive features aMCI- has quite different functional brain connectivity compared to

  12. Right hemisphere involvement in depression: toward a neuropsychological theory of negative affective experiences. (United States)

    Otto, M W; Yeo, R A; Dougher, M J


    Several lines of inquiry provide converging evidence for a critical role for the right cerebral hemisphere in negative affective experiences. This research includes the assessment of affective consequences of both focal cerebral lesions and pharmacological inactivation of one or the other hemisphere, as well as experimental and physiological techniques assessing differential hemispheric activation. The specific nature of right hemispheric involvement is conceptualized as a tendency to become activated by aversive experiences, and once activated, to process stimuli in a manner consistent with the right hemisphere's more negative affective tone. A theory of right hemisphere involvement in depressive affect is presented in detail and its relevance to clinical phenomena, e.g., the co-occurrence of depression and pain, and sex differences in depression, is examined, as is congruence with cognitive theories of depression.

  13. Classification of hemispheric monthly mean stratospheric potential vorticity fields

    Directory of Open Access Journals (Sweden)

    R. Huth

    Full Text Available Monthly mean NCEP reanalysis potential vorticity fields at the 650 K isentropic level over the Northern and Southern Hemispheres between 1979 and 1997 were studied using multivariate analysis tools. Principal component analysis in the T-mode was applied to demonstrate the validity of such statistical techniques for the study of stratospheric dynamics and climatology. The method, complementarily applied to both the raw and anomaly fields, was useful in determining and classifying the characteristics of winter and summer PV fields on both hemispheres, in particular, the well-known differences in the behaviour and persistence of the polar vortices. It was possible to identify such features as sudden warming events in the Northern Hemisphere and final warming dates in both hemispheres. The stratospheric impact of other atmospheric processes, such as volcanic eruptions, also identified though the results, must be viewed at this stage as tentative. An interesting change in behaviour around 1990 was detected over both hemispheres.

    Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; general circulation; climatology

  14. Dosimetric comparison between 3DCRT and IMRT using different multileaf collimators in the treatment of brain tumors. (United States)

    Ding, Meisong; Newman, Francis; Chen, Changhu; Stuhr, Kelly; Gaspar, Laurie E


    We investigated the differences between 3-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT), and the impact of collimator leaf-width on IMRT plans for the treatment of nonspherical brain tumors. Eight patients treated by 3DCRT with Novalis were selected. We developed 3 IMRT plans with different multileaf collimators (Novalis m3, Varian MLC-120, and Varian MLC-80) with the same treatment margins, number of beams, and gantry positions as in the 3DCRT treatment plans. Treatment planning utilized the BrainLAB treatment planning system. For each patient, the dose constraints and optimization parameters remained identical for all plans. The heterogeneity index, the percentage target coverage, critical structures, and normal tissue volumes receiving 50% of the prescription dose were calculated to compare the dosimetric difference. Equivalent uniform dose (EUD) and tumor control probability (TCP) were also introduced to evaluate the radiobiological effect for different plans. We found that IMRT significantly improved the target dose homogeneity compared to the 3DCRT. However, IMRT showed the same radiobiological effect as 3DCRT. For the brain tumors adjacent to (or partially overlapping with) critical structures, IMRT dramatically spared the volume of the critical structures to be irradiated. In IMRT plans, the smaller collimator leaf width could reduce the volume of critical structures irradiated to the 50% level for those partially overlapping with the brain tumors. For relatively large and spherical brain tumors, the smaller collimator leaf widths give no significant benefit.

  15. Analysis of the protein network of cholesterol homeostasis in different brain regions: an age and sex dependent perspective. (United States)

    Segatto, Marco; Di Giovanni, Annalaura; Marino, Maria; Pallottini, Valentina


    Although a great knowledge about the patho-physiological roles of cholesterol metabolism perturbation in several organs has been reached, scarce information is available on the regulation of cholesterol homeostasis in the brain where this lipid is involved in the maintenance of several of neuronal processes. Currently, no study is available in literature dealing how and if sex and age may modulate the major proteins involved in the regulatory network of cholesterol levels in different brain regions. Here, we investigated the behavior of 3-hydroxy 3-methylglutaryl coenzyme A reductase (HMGR) and low-density lipoprotein receptor (LDLr) in adult (3-month-old) and aged (12-month-old) male and female rats. The analyses were performed in four different brain regions: cortex, brain stem, hippocampus, and cerebellum which represent brain areas characterized by different neuronal cell types, metabolism, cytoarchitecture and white matter composition. The results show that in hippocampus HMGR is lower (30%) in adult female rats than in age-matched males. Differences in LDLr expression are also observable in old females with respect to age-matched males: the protein levels increase (40%) in hippocampus and decrease (20%) in cortex, displaying different mechanisms of regulation. The mechanism underlying the observed modifications are ascribable to Insig-1 and SREBP-1 modulation. The obtained data demonstrate that age- and sex-related differences in cholesterol homeostasis maintenance exist among brain regions, such as the hippocampus and the prefrontal cortex, important for learning, memory and affection. Some of these differences could be at the root of marked gender disparities observed in clinical disease incidence, manifestation, and prognosis.

  16. Differences in parent and teacher rating of everyday executive function in pediatric brain tumor survivors. (United States)

    Wochos, G C; Semerjian, C H; Walsh, K S


    We aimed to compare executive function (EF) outcomes in pediatric brain tumor (BT) survivors compared with healthy children (HC) across multiple settings. This retrospective cross-sectional study of BT survivors and age- and gender-matched HC analyzed scale patterns of parent and teacher ratings of EF (Behavior Ratings of Executive Function; BRIEF). We also analyzed relationships between groups and raters (parent/teacher) and clinical elevations across EF domains on the BRIEF. Group differences in aspects of EF emerged from parent ratings in working memory (WM), while significant interactions from teacher ratings emerged on nearly all EF scales. Parents reported impaired cognitive/behavioral flexibility in the BT group four times more than parents of HC. Teachers rated survivors significantly more poorly as a group on the majority of EF domains, and indicated clinical impairment in cognitive/behavioral flexibility, emotional regulation, self-starting/initiation, WM, and planning and organization (P/O) four to ten times more often than the teachers of HC. Overall, teacher ratings of EF impairment in pediatric BT survivors were significantly greater than parent ratings, who reported far fewer EF problems. Possible explanations for inter-rater discrepancies include potential reporting bias/response shift in parents and/or differences in EF demands across settings.

  17. Characterising the Analgesic Effect of Different Targets for Deep Brain Stimulation in Trigeminal Anaesthesia Dolorosa (United States)

    Sims-Williams, Hugh P.; Javed, Shazia; Pickering, Anthony E.; Patel, Nikunj K.


    Background Several deep brain stimulation (DBS) targets have been explored for the alleviation of trigeminal anaesthesia dolorosa. We aimed to characterise the analgesia produced from the periaqueductal grey (PAG) and centromedian-parafascicular (CmPf) nucleus using a within-subject design. Method We report a case series of 3 subjects implanted with PAG and CmPf DBS systems for the treatment of anaesthesia dolorosa. At follow-up, testing of onset and offset times, magnitude, and thermal and mechanical sensitivity was performed. Results The mean pain score of the cohort was acutely reduced by 56% (p effective at different stimulation frequencies and were not antagonistic in effect. Conclusion The mechanisms by which stimulation at these two targets produces analgesia are likely to be different. Certain pain qualities may respond more favourably to specific targets. Knowledge of onset and offset times for the targets can guide optimisation of stimulation settings. The use of more than one stimulation target may be beneficial and should be considered in anaesthesia dolorosa patients. PMID:27322524

  18. Brain Functional Connectivity is Different during VoluntaryConcentric and Eccentric Muscle Contraction

    Directory of Open Access Journals (Sweden)

    Wan X Yao


    Full Text Available Previous studies report greater activation in the cortical motor network in controlling eccentric contraction (EC than concentric contraction (CC of human skeletal muscles despite lower activation level of the muscle associated with EC. It is unknown, however, whether the strength of functional coupling between the primary motor cortex (M1 and other involved areas in the brain differs as voluntary movements are controlled by a network of regions in the primary, secondary and association cortices. Examining fMRI-based functional connectivity (FC offers an opportunity to measure strength of such coupling. To address the question, we examined functional MRI (fMRI data acquired during EC and CC (20 contractions each with similar movement distance and speed of the right first dorsal interosseous (FDI muscle in 11 young (20-32 years and healthy individuals and estimated FC between the M1 and a number of cortical regions in the motor control network. The major findings from the behavioral and fMRI-based FC analysis were that (1 no significant differences were seen in movement distance, speed and stability between the EC and CC; (2 significantly stronger mean FC was found for CC than EC. Our finding provides novel insights for a better understanding of the control mechanisms underlying voluntary movements produced by EC and CC. The finding is potentially helpful for guiding the development of targeted sport training and/or therapeutic programs for performance enhancement and injury prevention.

  19. Electrophysiological dynamic brain connectivity during symbolic magnitude comparison in children with different mathematics achievement levels. (United States)

    Gómez-Velázquez, Fabiola R; Vélez-Pérez, Hugo; Espinoza-Valdez, Aurora; Romo-Vazquez, Rebeca; Salido-Ruiz, Ricardo A; Ruiz-Stovel, Vanessa; Gallardo-Moreno, Geisa B; González-Garrido, Andrés A; Berumen, Gustavo


    Children with mathematical difficulties usually have an impaired ability to process symbolic representations. Functional MRI methods have suggested that early frontoparietal connectivity can predict mathematic achievements; however, the study of brain connectivity during numerical processing remains unexplored. With the aim of evaluating this in children with different math proficiencies, we selected a sample of 40 children divided into two groups [high achievement (HA) and low achievement (LA)] according to their arithmetic scores in the Wide Range Achievement Test, 4th ed.. Participants performed a symbolic magnitude comparison task (i.e. determining which of two numbers is numerically larger), with simultaneous electrophysiological recording. Partial directed coherence and graph theory methods were used to estimate and depict frontoparietal connectivity in both groups. The behavioral measures showed that children with LA performed significantly slower and less accurately than their peers in the HA group. Significantly higher frontocentral connectivity was found in LA compared with HA; however, when the connectivity analysis was restricted to parietal locations, no relevant group differences were observed. These findings seem to support the notion that LA children require greater memory and attentional efforts to meet task demands, probably affecting early stages of symbolic comparison.

  20. Qualitatively different coding of symbolic and nonsymbolic numbers in the human brain. (United States)

    Lyons, Ian M; Ansari, Daniel; Beilock, Sian L


    Are symbolic and nonsymbolic numbers coded differently in the brain? Neuronal data indicate that overlap in numerical tuning curves is a hallmark of the approximate, analogue nature of nonsymbolic number representation. Consequently, patterns of fMRI activity should be more correlated when the representational overlap between two numbers is relatively high. In bilateral intraparietal sulci (IPS), for nonsymbolic numbers, the pattern of voxelwise correlations between pairs of numbers mirrored the amount of overlap in their tuning curves under the assumption of approximate, analogue coding. In contrast, symbolic numbers showed a flat field of modest correlations more consistent with discrete, categorical representation (no systematic overlap between numbers). Directly correlating activity patterns for a given number across formats (e.g., the numeral "6" with six dots) showed no evidence of shared symbolic and nonsymbolic number-specific representations. Overall (univariate) activity in bilateral IPS was well fit by the log of the number being processed for both nonsymbolic and symbolic numbers. IPS activity is thus sensitive to numerosity regardless of format; however, the nature in which symbolic and nonsymbolic numbers are encoded is fundamentally different.

  1. Modeling and verification of hemispherical solar still using ANSYS CFD

    Energy Technology Data Exchange (ETDEWEB)

    Panchal, Hitesh N. [KSV University, Gujarat Power Engineering and Research Institute, Mehsana (India); Shah, P.K. [Silver Oak College of Engineering and Technology, Ahmedabad, Gujarat (India)


    In every efficient solar still design, water temperature, vapor temperature and distillate output, and difference between water temperature and inner glass cover temperatures are very important. Here, two dimensional three phase model of hemispherical solar still is made for evaporation as well as condensation process in ANSYS CFD. Simulation results like water temperature, vapor temperature, distillate output compared with actual experimental results of climate conditions of Mehsana (latitude of 23° 59’ and longitude of 72° 38) of hemispherical solar still. Water temperature and distillate output were good agreement with actual experimental results. Study shows that ANSYS-CFD is very powerful as well as efficient tool for design, comparison purpose of hemispherical solar still.

  2. Differences in distribution and regulation of astrocytic aquaporin-4 in human and rat hydrocephalic brain

    DEFF Research Database (Denmark)

    Skjolding, Anders Daehli; Holst, Anders Vedel; Broholm, Helle


    findings to human pathophysiology. This study compares expression of aquaporin-4 in hydrocephalic human brain with human controls and hydrocephalic rat brain. Methods:  Cortical biopsies from patients with chronic hydrocephalus (n=29) were sampled secondary to planned surgical intervention. Aquaporin-4...

  3. Brain Imaging and rTMS Studies of Individual Differences in Cognitive Processing (United States)


    Triple Helix Organization Lecture at Carnegie Mellon University, November 3, 2011, Pittsburgh, Pennsylvania. Neuroscience perspectives on comprehension...unavailability during a language task provides a model of the brain’s naturally occurring response to brain trauma, such as a stroke- induced focal lesion or a

  4. Two different gene loci related to the spatial patterning of brain ventricle in vertebrate

    Institute of Scientific and Technical Information of China (English)

    LUO Minna; LI Bingxia; TONG Ying; ZHAO Shufang; LUO Chen


    Observations on living embryonic brains and the microstructure of brain ventricle of goldfish revealed that there are two brain ventricle phenotypes in gynogenetic haploid embryos. One phenotype is as normal as that of the control inbreeding diploid embryos,which has normal differentiated forebrain, midbrain and hindbrain. Another phenotype is obviously abnormal, the brain patterning is irregular, and no distinct brain ventricle can be observed. The ratio of haploid embryos with normal brain pattern to that with abnormal brain pattern is 1:3. This ratio indicates that there are two gene loci involved in the spatial patterning of the brain ventricle. Since the possibility that deleterious recessive mutant alleles exist on both of the two gene loci had been excluded in this experiment, the phenotype represented the expressional state rather than the genotype of these two genes. Therefore, the ratio of 1∶ 3 suggests that the expressing probability for each copy of the two genes is 50%, and the regulatory mechanism of the expression is based on two sets of chromosomes, controlled by the rule of the diploid-dependent regulatory mechanism.

  5. Quasi-static axisymmetric eversion hemispherical domes made of elastomers (United States)

    Kabrits, Sergey A.; Kolpak, Eugeny P.


    The paper considers numerical solution for the problem of quasi-static axisymmetric eversion of a spherical shell (hemisphere) under action of external pressure. Results based on the general nonlinear theory of shells made of elastomers, proposed by K. F. Chernykh. It is used two models of shells based on the hypotheses of the Kirchhoff and Timoshenko, modified K.F. Chernykh for the case of hyperelastic rubber-like material. The article presents diagrams of equilibrium states of eversion hemispheres for both models as well as the shape of the shell at different points in the diagram.

  6. Mercuric chloride-induced reactive oxygen species and its effect on antioxidant enzymes in different regions of rat brain. (United States)

    Hussain, S; Rodgers, D A; Duhart, H M; Ali, S F


    The present study was undertaken to determine if in vitro exposure to mercuric chloride produces reactive oxygen species (ROS) in the synaptosomes prepared from various regions of rat brain. The effects of in vivo exposure to mercury on antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in different regions of rat brain were also investigated. Adult male Sprague-Dawley (CD) rats were dosed with 0, 1, 2.0 or 4.0 mg HgCl2/kg body weight, for 7 days. One week after the last dose, animals were sacrificed by decapitation, their brains were removed and dissected and frozen in dry ice prior to measuring the activities of these enzymes. The results demonstrated that in vitro exposure to mercury produced a concentration-dependent increase of ROS in different regions of the rat brain. In vivo exposure to mercury produced a significant decrease of total SOD, Cu, Zn-SOD and Mn-SOD activities in the cerebellum of rats treated with different doses of mercury. SOD activity did not vary significantly in cerebral cortex and brain stem. GPx activity declined in a dose-dependent manner in the cerebellum with a significant reduction in animals receiving the 4 mg HgCl2/kg body weight. The activity of GPx increased in the brain stem while unchanged in the cerebral cortex. The results demonstrate that inorganic mercury decreased SOD activity significantly in the cerebellum while GPx activity was affected in both cerebellum and brain stem. Therefore, it can be concluded that oxidative stress may contribute to the development of neurodegenerative disorders caused by mercury intoxication.

  7. Electroformation of uranium hemispherical shells

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, S.L.; Redey, L.; Vandegrift, G.F.; Vissers, D.R.


    This effort was directed at developing an electrochemical process for forming uniform and dendrite-free deposits of uranium from molten salts. This process is to be used for the electroformation of free-standing hemispherical shells of uranium for nuclear applications. Electrodeposition of uranium onto a substrate was accomplished with a fused chloride mixture containing 42 wt% UCl{sub 3} and a fused chloride-fluoride mixture containing 4 wt % UF{sub 4}. Under pulsed potential control at 504{degree}C, the chloride-fluoride mixture yielded the widest range of plating conditions for which dendrites could be avoided. Bipolar current pulse plating with both electrolytes gave good results, and successful application of this technique to a large tubular cathode has been demonstrated. 24 refs., 10 figs.

  8. Multi-modal magnetic resonance imaging in the acute and sub-acute phase of mild traumatic brain injury: can we see the difference? (United States)

    Toth, Arnold; Kovacs, Noemi; Perlaki, Gabor; Orsi, Gergely; Aradi, Mihaly; Komaromy, Hedvig; Ezer, Erzsebet; Bukovics, Peter; Farkas, Orsolya; Janszky, Jozsef; Doczi, Tamas; Buki, Andras; Schwarcz, Attila


    Advanced magnetic resonance imaging (MRI) methods were shown to be able to detect the subtle structural consequences of mild traumatic brain injury (mTBI). The objective of this study was to investigate the acute structural alterations and recovery after mTBI, using diffusion tensor imaging (DTI) to reveal axonal pathology, volumetric analysis, and susceptibility weighted imaging (SWI) to detect microhemorrhage. Fourteen patients with mTBI who had computed tomography with negative results underwent MRI within 3 days and 1 month after injury. High resolution T1-weighted imaging, DTI, and SWI, were performed at both time points. A control group of 14 matched volunteers were also examined following the same imaging protocol and time interval. Tract-Based Spatial Statistics (TBSS) were performed on DTI data to reveal group differences. T1-weighted images were fed into Freesurfer volumetric analysis. TBSS showed fractional anisotropy (FA) to be significantly (corrected p<0.05) lower, and mean diffusivity (MD) to be higher in the mTBI group in several white matter tracts (FA=40,737; MD=39,078 voxels) compared with controls at 72 hours after injury and still 1month later for FA. Longitudinal analysis revealed significant change (i.e., normalization) of FA and MD over 1 month dominantly in the left hemisphere (FA=3408; MD=7450 voxels). A significant (p<0.05) decrease in cortical volumes (mean 1%) and increase in ventricular volumes (mean 3.4%) appeared at 1 month after injury in the mTBI group. SWI did not reveal microhemorrhage in our patients. Our findings present dynamic micro- and macrostructural changes occurring in the acute to sub-acute phase in mTBI, in very mildly injured patients lacking microhemorrhage detectable by SWI. These results underscore the importance of strictly defined image acquisition time points when performing MRI studies on patients with mTBI.

  9. Describing different brain computer interface systems through a unique model: a UML implementation. (United States)

    Quitadamo, Lucia Rita; Marciani, Maria Grazia; Cardarilli, Gian Carlo; Bianchi, Luigi


    All the protocols currently implemented in brain computer interface (BCI) experiments are characterized by different structural and temporal entities. Moreover, due to the lack of a unique descriptive model for BCI systems, there is not a standard way to define the structure and the timing of a BCI experimental session among different research groups and there is also great discordance on the meaning of the most common terms dealing with BCI, such as trial, run and session. The aim of this paper is to provide a unified modeling language (UML) implementation of BCI systems through a unique dynamic model which is able to describe the main protocols defined in the literature (P300, mu-rhythms, SCP, SSVEP, fMRI) and demonstrates to be reasonable and adjustable according to different requirements. This model includes a set of definitions of the typical entities encountered in a BCI, diagrams which explain the structural correlations among them and a detailed description of the timing of a trial. This last represents an innovation with respect to the models already proposed in the literature. The UML documentation and the possibility of adapting this model to the different BCI systems built to date, make it a basis for the implementation of new systems and a mean for the unification and dissemination of resources. The model with all the diagrams and definitions reported in the paper are the core of the body language framework, a free set of routines and tools for the implementation, optimization and delivery of cross-platform BCI systems.

  10. Different inhibition of acetylcholinesterase in selected parts of the rat brain following intoxication with VX and Russian VX. (United States)

    Hajek, Petr; Bajgar, Jiri; Slizova, Dasa; Krs, Otakar; Kuca, Kamil; Capek, Lukas; Fusek, Josef


    Differences between acetylcholinesterase (AChE) inhibition in the brain structures following VX and RVX exposure are not known as well as information on the possible correlation of biochemical and histochemical methods detecting AChE activity. Therefore, inhibition of AChE in different brain parts detected by histochemical and biochemical techniques was compared in rats intoxicated with VX and RVX. AChE activities in defined brain regions 30 min after treating rats with VX and Russian VX intramuscularly (1.0 x LD(50)) were determined by using biochemical and histochemical methods. AChE inhibition was less expressed for RVX, in comparison with VX. Frontal cortex and pontomedullar areas containing ncl. reticularis has been found as the most sensitive areas for the action of VX. For RVX, these structures were determined to be frontal cortex, dorsal septum, and hippocampus, respectively. Histochemical and biochemical results were in good correlation (R(xy) = 0.8337). Determination of AChE activity in defined brain structures was a more sensitive parameter for VX or RVX exposure than the determination of AChE activity in the whole-brain homogenate. This activity represents a "mean" of the activities in different structures. Thus, AChE activity is the main parameter investigated in studies searching for target sites following nerve-agent poisoning contributing to better understanding of toxicodynamics of nerve agents.

  11. From the Left to the Right: How the Brain Compensates Progressive Loss of Language Function (United States)

    Thiel, Alexander; Habedank, Birgit; Herholz, Karl; Kessler, Josef; Winhuisen, Lutz; Haupt, Walter F.; Heiss, Wolf-Dieter


    In normal right-handed subjects language production usually is a function of the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this function. Sometimes, but not always, areas of the right hemisphere which are homologous to language areas of the…

  12. Differences on Brain Connectivity in Adulthood Are Present in Subjects with Iron Deficiency Anemia in Infancy (United States)

    Algarin, Cecilia; Karunakaran, Keerthana Deepti; Reyes, Sussanne; Morales, Cristian; Lozoff, Betsy; Peirano, Patricio; Biswal, Bharat


    Iron deficiency continues to be the most prevalent micronutrient deficit worldwide. Since iron is involved in several processes including myelination, dopamine neurotransmission and neuronal metabolism, the presence of iron deficiency anemia (IDA) in infancy relates to long-lasting neurofunctional effects. There is scarce data regarding whether these effects would extend to former iron deficient anemic human adults. Resting state functional magnetic resonance imaging (fMRI) is a novel technique to explore patterns of functional connectivity. Default Mode Network (DMN), one of the resting state networks, is deeply involved in memory, social cognition and self-referential processes. The four core regions consistently identified in the DMN are the medial prefrontal cortex, posterior cingulate/retrosplenial cortex and left and right inferior parietal cortex. Therefore to investigate the DMN in former iron deficient anemic adults is a particularly useful approach to elucidate de long term effects on functional brain. We conducted this research to explore the connection between IDA in infancy and altered patterns of resting state brain functional networks in young adults. Resting-state fMRI studies were performed to 31 participants that belong to a follow-up study since infancy. Of them, 14 participants were former iron deficient anemic in infancy and 17 were controls, with mean age of 21.5 years (±1.5) and 54.8% were males. Resting-state fMRI protocol was used and the data was analyzed using the seed based connectivity statistical analysis to assess the DMN. We found that compared to controls, former iron deficient anemic subjects showed posterior DMN decreased connectivity to the left posterior cingulate cortex (PCC), whereas they exhibited increased anterior DMN connectivity to the right PCC. Differences between groups were also apparent in the left medial frontal gyrus, with former iron deficient anemic participants having increased connectivity with areas included

  13. Asymmetric field-aligned currents in the conjugate hemispheres (United States)

    Reistad, J. P.; Ostgaard, N.; Oksavik, K.; Laundal, K. M.


    Earlier studies using simultaneous imaging from space of the Aurora Borealis (Northern Hemisphere) and Aurora Australis (Southern Hemisphere) have revealed that the aurora can experience a high degree of asymmetry between the two hemispheres. Using 19 hours of simultaneous global imaging from both hemispheres (IMAGE satellite in north and Polar satellite in south) in conjunction with the entire IMAGE WIC database, we investigate the importance of various mechanisms thought to generate the asymmetries seen in global imaging. In terms of asymmetric or interhemispheric field-aligned currents, three candidate mechanisms have been suggested: 1) Hemispheric differences in solar wind dynamo efficiency mainly controlled by IMF Bx leading to asymmetric region 1 currents; 2) conductivity differences in conjugate areas; and 3) penetration of IMF By into the closed magnetosphere possibly generating a pair of oppositely directed interhemispheric currents. From the 19 hour conjugate dataset we find that the solar wind dynamo is likely to be the most important controlling mechanism for asymmetric bright aurora in the polar part of the nightside oval. Here we present statistical analyses of candidates 1) and 3). Using the entire IMAGE WIC database, a statistical analysis of the auroral brightness distribution along and across the Northern Hemisphere oval is carried out. For each candidate, two extreme cases (+/- IMF Bx for 1) and +/- IMF By for 3)) are compared during times non-favorable for the other two mechanisms. Our results indicate that solar wind dynamo induced currents play an important role for the nightside auroral brightness in an average sense. Also, signatures of interhemispheric currents due to IMF By penetration are seen in our statistics, although this effect is somehow weaker.

  14. An experimental study on the mechanical properties of rat brain tissue using different stress-strain definitions. (United States)

    Karimi, Alireza; Navidbakhsh, Mahdi


    There are different stress-strain definitions to measure the mechanical properties of the brain tissue. However, there is no agreement as to which stress-strain definition should be employed to measure the mechanical properties of the brain tissue at both the longitudinal and circumferential directions. It is worth knowing that an optimize stress-strain definition of the brain tissue at different loading directions may have implications for neuronavigation and surgery simulation through haptic devices. This study is aimed to conduct a comparative study on different results are given by the various definitions of stress-strain and to recommend a specific definition when testing brain tissues. Prepared cylindrical samples are excised from the parietal lobes of rats' brains and experimentally tested by applying load on both the longitudinal and circumferential directions. Three stress definitions (second Piola-Kichhoff stress, engineering stress, and true stress) and four strain definitions (Almansi-Hamel strain, Green-St. Venant strain, engineering strain, and true strain) are used to determine the elastic modulus, maximum stress and strain. The highest non-linear stress-strain relation is observed for the Almansi-Hamel strain definition and it may overestimate the elastic modulus at different stress definitions at both the longitudinal and circumferential directions. The Green-St. Venant strain definition fails to address the non-linear stress-strain relation using different definitions of stress and triggers an underestimation of the elastic modulus. The results suggest the application of the true stress-true strain definition for characterization of the brain tissues mechanics since it gives more accurate measurements of the tissue's response using the instantaneous values.

  15. Hemispheric lateralization of motor thresholds in relation to stuttering.

    Directory of Open Access Journals (Sweden)

    Per A Alm

    Full Text Available Stuttering is a complex speech disorder. Previous studies indicate a tendency towards elevated motor threshold for the left hemisphere, as measured using transcranial magnetic stimulation (TMS. This may reflect a monohemispheric motor system impairment. The purpose of the study was to investigate the relative side-to-side difference (asymmetry and the absolute levels of motor threshold for the hand area, using TMS in adults who stutter (n = 15 and in controls (n = 15. In accordance with the hypothesis, the groups differed significantly regarding the relative side-to-side difference of finger motor threshold (p = 0.0026, with the stuttering group showing higher motor threshold of the left hemisphere in relation to the right. Also the absolute level of the finger motor threshold for the left hemisphere differed between the groups (p = 0.049. The obtained results, together with previous investigations, provide support for the hypothesis that stuttering tends to be related to left hemisphere motor impairment, and possibly to a dysfunctional state of bilateral speech motor control.

  16. Bilateral cerebral hemispheric infarction associated with sildenafil citrate (Viagra) use. (United States)

    Kim, K-K; Kim, D G; Ku, Y H; Lee, Y J; Kim, W-C; Kim, O J; Kim, H S


    Sildenafil citrate (Viagra) is one of the frequently prescribed drugs for men with erectile dysfunction. We describe a 52-year-old man with bilateral middle cerebral artery (MCA) territory infarction after sildenafil use. He ingested 100 mg of sildenafil and about 1 h later, he complained of chest discomfort, palpitation and dizziness followed by mental obtundation, global aphasia and left hemiparesis. Brain magnetic resonance imaging documented acute bilateral hemispheric infarction, and cerebral angiography showed occluded bilateral MCA. Despite significant bilateral MCA stenosis and cerebral infarction, systemic hypotension persisted for a day. We presume that cerebral infarction was caused by cardioembolism with sildenafil use.

  17. Regional differences in the expression of brain-derived neurotrophic factor (BDNF) pro-peptide, proBDNF and preproBDNF in the brain confer stress resilience. (United States)

    Yang, Bangkun; Yang, Chun; Ren, Qian; Zhang, Ji-Chun; Chen, Qian-Xue; Shirayama, Yukihiko; Hashimoto, Kenji


    Using learned helplessness (LH) model of depression, we measured protein expression of brain-derived neurotrophic factor (BDNF) pro-peptide, BDNF precursors (proBDNF and preproBDNF) in the brain regions of LH (susceptible) and non-LH rats (resilience). Expression of preproBDNF, proBDNF and BDNF pro-peptide in the medial prefrontal cortex of LH rats, but not non-LH rats, was significantly higher than control rats, although expression of these proteins in the nucleus accumbens of LH rats was significantly lower than control rats. This study suggests that regional differences in conversion of BDNF precursors into BDNF and BDNF pro-peptide by proteolytic cleavage may contribute to stress resilience.

  18. Different Brain Responses to Pain and Its Expectation in the Dental Chair. (United States)

    Racek, A J; Hu, X; Nascimento, T D; Bender, M C; Khatib, L; Chiego, D; Holland, G R; Bauer, P; McDonald, N; Ellwood, R P; DaSilva, A F


    A dental appointment commonly prompts fear of a painful experience, yet we have never fully understood how our brains react to the expectation of imminent tooth pain once in a dental chair. In our study, 21 patients with hypersensitive teeth were tested using nonpainful and painful stimuli in a clinical setting. Subjects were tested in a dental chair using functional near-infrared spectroscopy to measure cortical activity during a stepwise cold stimulation of a hypersensitive tooth, as well as nonpainful control stimulation on the same tooth. Patients' sensory-discriminative and emotional-cognitive cortical regions were studied through the transition of a neutral to a painful stimulation. In the putative somatosensory cortex contralateral to the stimulus, 2 well-defined hemodynamic peaks were detected in the homuncular orofacial region: the first peak during the nonpainful phase and a second peak after the pain threshold was reached. Moreover, in the upper-left and lower-right prefrontal cortices, there was a significant active hemodynamic response in only the first phase, before the pain. Subsequently, the same prefrontal cortical areas deactivated after a painful experience had been reached. Our study indicates for the first time that pain perception and expectation elicit different hemodynamic cortical responses in a dental clinical setting.

  19. Differences in brain circuitry for appetitive and reactive aggression as revealed by realistic auditory scripts

    Directory of Open Access Journals (Sweden)

    James Kenneth Moran


    Full Text Available Aggressive behavior is thought to divide into two motivational elements: The first being a self-defensively motivated aggression against threat and a second, hedonically motivated ‘appetitive’ aggression. Appetitive aggression is the less understood of the two, often only researched within abnormal psychology. Our approach is to understand it as a universal and adaptive response, and examine the functional neural activity of ordinary men (N=50 presented with an imaginative listening task involving a murderer describing a kill. We manipulated motivational context in a between-subjects design to evoke appetitive or reactive aggression, against a neutral control, measuring activity with Magnetoencephalography (MEG. Results show differences in left frontal regions in delta (2-5 Hz and alpha band (8-12 Hz for aggressive conditions and right parietal delta activity differentiating appetitive and reactive aggression. These results validate the distinction of reward-driven appetitive aggression from reactive aggression in ordinary populations at the level of functional neural brain circuitry.

  20. Functional brain networks related to individual differences in human intelligence at rest. (United States)

    Hearne, Luke J; Mattingley, Jason B; Cocchi, Luca


    Intelligence is a fundamental ability that sets humans apart from other animal species. Despite its importance in defining human behaviour, the neural networks responsible for intelligence are not well understood. The dominant view from neuroimaging work suggests that intelligent performance on a range of tasks is underpinned by segregated interactions in a fronto-parietal network of brain regions. Here we asked whether fronto-parietal interactions associated with intelligence are ubiquitous, or emerge from more widespread associations in a task-free context. First we undertook an exploratory mapping of the existing literature on functional connectivity associated with intelligence. Next, to empirically test hypotheses derived from the exploratory mapping, we performed network analyses in a cohort of 317 unrelated participants from the Human Connectome Project. Our results revealed a novel contribution of across-network interactions between default-mode and fronto-parietal networks to individual differences in intelligence at rest. Specifically, we found that greater connectivity in the resting state was associated with higher intelligence scores. Our findings highlight the need to broaden the dominant fronto-parietal conceptualisation of intelligence to encompass more complex and context-specific network dynamics.

  1. Three Types of Cortical Layer 5 Neurons That Differ in Brain-wide Connectivity and Function. (United States)

    Kim, Euiseok J; Juavinett, Ashley L; Kyubwa, Espoir M; Jacobs, Matthew W; Callaway, Edward M


    Cortical layer 5 (L5) pyramidal neurons integrate inputs from many sources and distribute outputs to cortical and subcortical structures. Previous studies demonstrate two L5 pyramid types: cortico-cortical (CC) and cortico-subcortical (CS). We characterize connectivity and function of these cell types in mouse primary visual cortex and reveal a new subtype. Unlike previously described L5 CC and CS neurons, this new subtype does not project to striatum [cortico-cortical, non-striatal (CC-NS)] and has distinct morphology, physiology, and visual responses. Monosynaptic rabies tracing reveals that CC neurons preferentially receive input from higher visual areas, while CS neurons receive more input from structures implicated in top-down modulation of brain states. CS neurons are also more direction-selective and prefer faster stimuli than CC neurons. These differences suggest distinct roles as specialized output channels, with CS neurons integrating information and generating responses more relevant to movement control and CC neurons being more important in visual perception.

  2. Serum Brain-Derived Neurotrophic Factor Levels in Different Neurological Diseases

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    Mariacarla Ventriglia


    Full Text Available Consistent evidence indicates the involvement of the brain-derived neurotrophic factor (BDNF in neurodegenerative disorders such as Alzheimer's disease (AD and Parkinson’s disease (PD. In the present study, we compared serum BDNF in 624 subjects: 266 patients affected by AD, 28 by frontotemporal dementia (FTD, 40 by Lewy body dementia (LBD, 91 by vascular dementia (VAD, 30 by PD, and 169 controls. Our results evidenced lower BDNF serum levels in AD, FTD, LBD, and VAD patients (P<0.001 and a higher BDNF concentration in patients affected by PD (P=0.045. Analyses of effects of pharmacological treatments suggested significantly higher BDNF serum levels in patients taking mood stabilizers/antiepileptics (P=0.009 and L-DOPA (P<0.001 and significant reductions in patients taking benzodiazepines (P=0.020. In conclusion, our results support the role of BDNF alterations in neurodegenerative mechanisms common to different forms of neurological disorders and underline the importance of including drug treatment in the analyses to avoid confounding effects.

  3. Using deep belief network modelling to characterize differences in brain morphometry in schizophrenia (United States)

    Pinaya, Walter H. L.; Gadelha, Ary; Doyle, Orla M.; Noto, Cristiano; Zugman, André; Cordeiro, Quirino; Jackowski, Andrea P.; Bressan, Rodrigo A.; Sato, João R.


    Neuroimaging-based models contribute to increasing our understanding of schizophrenia pathophysiology and can reveal the underlying characteristics of this and other clinical conditions. However, the considerable variability in reported neuroimaging results mirrors the heterogeneity of the disorder. Machine learning methods capable of representing invariant features could circumvent this problem. In this structural MRI study, we trained a deep learning model known as deep belief network (DBN) to extract features from brain morphometry data and investigated its performance in discriminating between healthy controls (N = 83) and patients with schizophrenia (N = 143). We further analysed performance in classifying patients with a first-episode psychosis (N = 32). The DBN highlighted differences between classes, especially in the frontal, temporal, parietal, and insular cortices, and in some subcortical regions, including the corpus callosum, putamen, and cerebellum. The DBN was slightly more accurate as a classifier (accuracy = 73.6%) than the support vector machine (accuracy = 68.1%). Finally, the error rate of the DBN in classifying first-episode patients was 56.3%, indicating that the representations learned from patients with schizophrenia and healthy controls were not suitable to define these patients. Our data suggest that deep learning could improve our understanding of psychiatric disorders such as schizophrenia by improving neuromorphometric analyses.

  4. EEG Bands of Wakeful Rest, Slow-Wave and Rapid-Eye-Movement Sleep at Different Brain Areas in Rats (United States)

    Jing, Wei; Wang, Yanran; Fang, Guangzhan; Chen, Mingming; Xue, Miaomiao; Guo, Daqing; Yao, Dezhong; Xia, Yang


    Accumulating evidence reveals that neuronal oscillations with various frequency bands in the brain have different physiological functions. However, the frequency band divisions in rats were typically based on empirical spectral distribution from limited channels information. In the present study, functionally relevant frequency bands across vigilance states and brain regions were identified using factor analysis based on 9 channels EEG signals recorded from multiple brain areas in rats. We found that frequency band divisions varied both across vigilance states and brain regions. In particular, theta oscillations during REM sleep were subdivided into two bands, 5–7 and 8–11 Hz corresponding to the tonic and phasic stages, respectively. The spindle activities of SWS were different along the anterior-posterior axis, lower oscillations (~16 Hz) in frontal regions and higher in parietal (~21 Hz). The delta and theta activities co-varied in the visual and auditory cortex during wakeful rest. In addition, power spectra of beta oscillations were significantly decreased in association cortex during REM sleep compared with wakeful rest. These results provide us some new insights into understand the brain oscillations across vigilance states, and also indicate that the spatial factor should not be ignored when considering the frequency band divisions in rats. PMID:27536231

  5. Total hemispherical emissivity of Inconel 718

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    Keller, Benjamin P.; Nelson, Shawn E.; Walton, Kyle L.; Ghosh, Tushar K.; Tompson, Robert V.; Loyalka, Sudarshan K., E-mail:


    Highlights: • We have measured the total hemispherical emissivity for Inconel 718 from about 600–1250 K. • Oxidation in air at 1073 K resulted in an increase in emissivity. • Sandblasting of Inconel 718 was also observed to increase the emissivity. • Coating of graphite powder onto the ‘as-received’ Inconel 718 showed no increase in the emissivity. • Coating of graphite powder onto the 220 grit sandblasted Inconel 718 did show an increase in emissivity. - Abstract: Total hemispherical emissivity for Inconel 718 was measured in anticipation of its application in Very High Temperature Gas Reactors (VHTRs). A majority of current emissivity data for Inconel 718 is in the form of spectral measurements. The data presented here were obtained with an experimental apparatus based on the standard ASTM C835-06 for total hemispherical emittance. Measurements of Inconel 718 were made for four different surface types including: (i) ‘as-received’ from the manufacturer, (ii) oxidized in air and humidified helium, (iii) sandblasted with aluminum oxide powder, and (iv) with a thin coating of nuclear grade graphite powder (grade NGB-18). The emissivity for the ‘as-received’ sample ranged from 0.21 to 0.28 in the temperature interval from 760 K to 1275 K. Oxidation in air at 1073 K resulted in an increase in emissivity into the range from 0.2 at 650 K to 0.52 at 1200 K. There was no dependence on the oxidation times studied here. Oxidation with humidified helium at 1073 K produced less of an increase in emissivity than the oxidation in air but there was an increase up to the range from 0.2 at 600 K to 0.35 at 1200 K. Sandblasting of Inconel 718 was also observed to increase the emissivity up to the range from 0.43 at 780 K to 0.53 at 1270 K when 60 grit sized powder was used and up to the range from 0.45 at 683 K to 0.57 at 1267 K when 120 and 220 grit sized powders were used. Coating of graphite powder onto the ‘as-received’ Inconel 718 showed no increase

  6. The Cost of Action Miscues: Hemispheric Asymmetries (United States)

    Shenal, Brian V.; Hinze, Stephan; Heilman, Kenneth M.


    Adaptive behaviors require preparation and when necessary inhibition or alteration of actions. The right hemisphere has been posited to be dominant for preparatory motor activation. This experiment was designed to learn if there are hemispheric asymmetries in the control of altered plans of actions. Cues, both valid and invalid, which indicate the…

  7. Some growth factors in neoplastic tissues of brain tumors of different histological structure

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    O. I. Kit


    -β1 (BenderMedSystem, Austria.Results. We have found both common and distinctive features in the content of growth factors in neoplastic tissues of different histological structure and corresponding peritumoral areas. Common metabolic features of glioblastomas, brain metastases and meningiomas include various increase in the level of VEGF-A, VEGF-R1, VEGF-C, IFR-1, IFR-2 and VEGF-C/VEGF-R3 index ratio. Differences included the fact that the level of VEGF-R3 and TGF-β1 did not increase in the benign tumor, while the level of EGF and VEGF-A/VEGF-R1 index ratio were below the control values in contrast to the values of malignant tumors.Conclusions• In the neoplastic tissues of glioblastomas and peritumoral area there is a strong positive correlation between the level of VEGF-A with the level of EGF, IGF-1, IGF-II and TGF-β1.• In the metastatic tissue there is a strong positive correlation between the level of VEGF-A with the level of EGF, IGF-1, IGF-II and TGF-β1. However, correlations had a different nature in the peritumoral zone tissues near to metastases: there was a strong positive correlation of VEGF-A level with TGF-β1 only, while there was a strong negative correlation with the level of IGF-1 and IGF-II, there were no correlations with EGF level.• In meningioma tissues VEGF-A levels correlated only with the level of insulin-like growth factors: there was a strong positive correlation with IGF-1 and IGF-II, correlation has been found with the level of EGF and TGF-β1.• In descending order VEGF-C was detected in glioblastoma tissue, in metastatic tumors, meningiomas, peritumoral zones of glioblastomas and metastases. However, in all of these samples the level of the studied factor significantly exceeded the value in intact brain tissue. VEGFR-3 level was elevated in glioblastoma tissue only. 

  8. Influence of age on brain edema formation, secondary brain damage and inflammatory response after brain trauma in mice.

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    Ralph Timaru-Kast

    Full Text Available After traumatic brain injury (TBI elderly patients suffer from higher mortality rate and worse functional outcome compared to young patients. However, experimental TBI research is primarily performed in young animals. Aim of the present study was to clarify whether age affects functional outcome, neuroinflammation and secondary brain damage after brain trauma in mice. Young (2 months and old (21 months male C57Bl6N mice were anesthetized and subjected to a controlled cortical impact injury (CCI on the right parietal cortex. Animals of both ages were randomly assigned to 15 min, 24 h, and 72 h survival. At the end of the observation periods, contusion volume, brain water content, neurologic function, cerebral and systemic inflammation (CD3+ T cell migration, inflammatory cytokine expression in brain and lung, blood differential cell count were determined. Old animals showed worse neurological function 72 h after CCI and a high mortality rate (19.2% compared to young (0%. This did not correlate with histopathological damage, as contusion volumes were equal in both age groups. Although a more pronounced brain edema formation was detected in old mice 24 hours after TBI, lack of correlation between brain water content and neurological deficit indicated that brain edema formation is not solely responsible for age-dependent differences in neurological outcome. Brains of old naïve mice were about 8% smaller compared to young naïve brains, suggesting age-related brain atrophy with possible decline in plasticity. Onset of cerebral inflammation started earlier and primarily ipsilateral to damage in old mice, whereas in young mice inflammation was delayed and present in both hemispheres with a characteristic T cell migration pattern. Pulmonary interleukin 1β expression was up-regulated after cerebral injury only in young, not aged mice. The results therefore indicate that old animals are prone to functional deficits and strong ipsilateral cerebral

  9. Theory of mind and pragmatic understanding following right hemisphere damage. (United States)

    Siegal, M; Carrington, J; Radel, M


    It has been maintained that 3-year-olds' difficulties in correctly predicting the undesired outcome of false beliefs reflects difficulties in interpreting the implications of conversations rather than a conceptual limitation in their theory of mind. As the right hemisphere has been seen to be responsible for the interpretation of the pragmatic aspects of communication, right-hemisphere-damaged (RHD) and left-hemisphere-damaged (LHD) adult patients in our study were compared on their ability to correctly draw inferences in false belief tasks. The RHD but not the LHD patients were found to have difficulties similar to those of young children in understanding the conversational implications test questions. Most reported that a central story character would look for a pet in the place where it was really located instead of where the character believed it was located. However, when then asked in a control question where the pet really was, the RHD patients often switched their answer to the test question and referred to the believed location. Removal of the need to infer the questioner's meaning enabled both RHD and LHD subjects to make correct false belief predictions. The results are discussed in terms of the effects of brain damage on spatial memory and the pragmatic demands of theory of mind tasks.

  10. The influence of sex chromosome aneuploidy on brain asymmetry. (United States)

    Rezaie, Roozbeh; Daly, Eileen M; Cutter, William J; Murphy, Declan G M; Robertson, Dene M W; DeLisi, Lynn E; Mackay, Clare E; Barrick, Thomas R; Crow, Timothy J; Roberts, Neil


    The cognitive deficits present in individuals with sex chromosome aneuploidies suggest that hemispheric differentiation of function is determined by an X-Y homologous gene [Crow (1993); Lancet 342:594-598]. In particular, females with Turner's syndrome (TS) who have only one X-chromosome exhibit deficits of spatial ability whereas males with Klinefelter's syndrome (KS) who possess a supernumerary X-chromosome are delayed in acquiring words. Since spatial and verbal abilities are generally associated with right and left hemispheric function, such deficits may relate to anomalies of cerebral asymmetry. We therefore applied a novel image analysis technique to investigate the relationship between sex chromosome dosage and structural brain asymmetry. Specifically, we tested Crow's prediction that the magnitude of the brain torque (i.e., a combination of rightward frontal and leftward occipital asymmetry) would, as a function of sex chromosome dosage, be respectively decreased in TS women and increased in KS men, relative to genotypically normal controls. We found that brain torque was not significantly different in TS women and KS men, in comparison to controls. However, TS women exhibited significantly increased leftward brain asymmetry, restricted to the posterior of the brain and focused on the superior temporal and parietal-occipital association cortex, while KS men showed a trend for decreased brain asymmetry throughout the frontal lobes. The findings suggest that the number of sex chromosomes influences the development of brain asymmetry not simply to modify the torque but in a complex pattern along the antero-posterior axis.


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    Amani Abdelrazag Elfaki


    Full Text Available Advances in neuroimaging have enabled studies of specific neuroanatomical abnormalities with relevance to schizophrenia. This study quantified structural alterations on brain magnetic resonance (MR images of patients with schizophrenia. MR brain imaging was done on 88 control and 57 schizophrenic subjects and Dicom images were analyzed with ImageJ software. The brain volume was estimated with the planimetric stereological technique. The volume fraction of brain structures was also estimated. The results showed that, the mean volume of right, left, and total hemispheres in controls were 551, 550, and 1101 cm³, respectively. The mean volumes of right, left, and total hemispheres in schizophrenics were 513, 512, and 1026 cm³, respectively. The schizophrenics’ brains were smaller than the controls (p < 0.05. The mean volume of total white matter of controls (516 cm³ was bigger than the schizophrenics’ volume (451 cm³, (p < 0.05. The volume fraction of total white matter was also lower in schizophrenics (p < 0.05. Volume fraction of the lateral ventricles was higher in schizophrenics (p < 0.05. According to the findings, the volumes of schizophrenics’ brain were smaller than the controls and the volume fractional changes in schizophrenics showed sex dependent differences. We conclude that stereological analysis of MR brain images is useful for quantifying schizophrenia related structural changes.

  12. Functional Magnetic Resonance Imaging of Different Genders in the Activation of Brain Emotional Centers

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    L. Podsiadło


    Full Text Available Background/Objective: The main aim of this study"nwas to reveal gender differences in the localization"nof brain emotional centers for positive and negative"nstimuli."nPatients and Methods: Forty right-handed young"nvolunteers (age range, 18-36 years, 21 men and 19"nwomen were examined using MR 1.5 T Signa Horizon"n(GEMS. Functional images were acquired using a"nspin-echo echoplanar sequence sensitive to blood"noxygenation level dependent (BOLD contrast, with"nthe following parameters: TR=3000 ms, TE= 60 ms,"nFOV=2821 cm, matrix 9696,1 NEX. For emotion induction, affectively negative, positive and neutral"npictures were used. Positive and negative cues were"ntaken from the International Affecive Picture System"n(IAPS. There were two runs, in the first run subjects"nsaw only negatively valenced pictures, during the"nsecond run only positive pictures were shown."nResults: For positive stimuli, the greatest differences"nin activation in women compared to men were"ndetected in the right superior temporal gyrus. For"nnegative stimuli, the greatest differences in activation"nin women compared to men were detected in the left"nthalamus. For positive stimuli, the greatest differences"nin activation in men compared to women were"ndetected in the bilateral occipital lobes as well as the"nbilateral fusiform gyrus. For negative stimuli, the"ngreatest differences in activation in men compared to"nwomen were detected in the left insula."nConclusion: There are statistically significant"ndifferences in activation of the emotional centers"nbetween females and males for the positive and"ndenoised, extracted and visualized. Follow-up CT"nexam and/or clinical pictures confirmed or excluded"nthe diagnosis. Based on preliminary results and"nconcluded efficiency limitations additional postprocessing"nbased on curvelets decomposition and"nimproved segmentation of stroke susceptible regions"nhas been designed and performed later on for selected"nexaminations regarded as

  13. Behavioral Laterality of the Brain: Support for the Binary Construct of Hemisity

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    Bruce Eldine Morton


    Full Text Available Three terms define brain behavioral laterality: Hemispheric dominance identifies the cerebral hemisphere producing one’s first language. Hemispheric asymmetry locates the brain side of non-language skills. A third term is needed to describe a person’s binary thinking, learning, and behaving styles. Since the 1950s split-brain studies, evidence has accumulated that individuals with right or left brain behavioral orientations (RPs or LPs exist. Originally, hemisphericity sought, but failed, to confirm the existence of such individual differences, due to its assertion that each individual lay somewhere on a gradient between competing left and right brain extremes. Recently, hemisity, a more accurate behavioral laterality context, has emerged. It posits that one’s behavioral laterality is binary: i.e., inherently either right or left brain-oriented. This insight enabled the quantitative determination of right or left behavioral laterality of thousands of subjects. MRI scans of right and left brain-oriented groups revealed two neuroanatomical differences. The first was an asymmetry of an executive element in the anterior cingulate cortex. This provided hemisity both a rationale and a primary standard. RPs and LPs gave opposite answers to many behavioral preference either-or, forced choice questions. This showed that several sex vs. hemisity traits are being conflated by society. Such was supported by the second neuroanatomical difference between the hemisity subtypes, that RPs of either sex had up to three times larger corpus callosi than LPs. Individuals of the same hemisity but opposite sex had more personality traits in common than those of the same sex but different hemisity. Although hemisity subtypes were equally represented in the general population, the process of higher education and career choice caused substantial hemisity sorting among the professions. Hemisity appears to be a valid and promising area for quantitative research of

  14. Implementation of different histochemical methods in diagnostics of brain Aspergillosis in turkey chicks

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    Kureljušić Branislav


    Full Text Available Aspergillosis is a frequent fungal disease in different species of birds and mammals caused by fungi of the genus Aspergillus. It is characterized by inflammatory changes primarily in the respiratory system, even though it sometimes takes on a generalized form when several organ systems are affected. Mucotic-granulomatous meningoencephalitis with a predominant localization in the cerebellum has been described in turkeys, ducks and geese. Within this paper, examinations have been performed on a flock of broiler turkeys aged 12 days who had sustained evident neurological disorders in the form of ataxy, torticollis, paresis, and paralysis of the hind extremities and wings. In three of the ten autopsied chicks the macroscopic findings indicated granulomatous encephalitis of the cerebellum. A white-coloured granuloma, around 3mm in diameter, was situated cranioventrally and was clearly visible on the sagital section of the cerebellum. Mucological examinations of the cerebellum lesion resulted in the isolation of the fungi Aspergillus fumigatus. Haematoxylin-eosin (HE, Grocott and PAS methods were used for the evaluation of histopathological changes and proving Aspergillus fumigatusa hyphae. The microscopic examination of brain tissue sections stained with the HE method revealed the existence of a granuloma with a centrally placed necrotic area. The necrotic area was infiltrated with heterophilic granulocytes and surrounded by macrophage, giant cells and lymphocytes. A connective tissue capsule was located on the periphery of the granuloma. The fungi hyphae, as integral parts of the granuloma, were difficult to observe, and in some samples stained using the HE method they could not be seen at all. On the other hand, sections stanied using the Grocott and PAS methods showed prominent septed and branched hyphae in different parts of the granuloma. With the objective of making an etiological diagnosis of mucotic diseases, it is necessary to apply several

  15. Does the reading of different orthographies produce distinct brain activity patterns? An ERP study.

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    Irit Bar-Kochva

    Full Text Available Orthographies vary in the degree of transparency of spelling-sound correspondence. These range from shallow orthographies with transparent grapheme-phoneme relations, to deep orthographies, in which these relations are opaque. Only a few studies have examined whether orthographic depth is reflected in brain activity. In these studies a between-language design was applied, making it difficult to isolate the aspect of orthographic depth. In the present work this question was examined using a within-subject-and-language investigation. The participants were speakers of Hebrew, as they are skilled in reading two forms of script transcribing the same oral language. One form is the shallow pointed script (with diacritics, and the other is the deep unpointed script (without diacritics. Event-related potentials (ERPs were recorded while skilled readers carried out a lexical decision task in the two forms of script. A visual non-orthographic task controlled for the visual difference between the scripts (resulting from the addition of diacritics to the pointed script only. At an early visual-perceptual stage of processing (~165 ms after target onset, the pointed script evoked larger amplitudes with longer latencies than the unpointed script at occipital-temporal sites. However, these effects were not restricted to orthographic processing, and may therefore have reflected, at least in part, the visual load imposed by the diacritics. Nevertheless, the results implied that distinct orthographic processing may have also contributed to these effects. At later stages (~340 ms after target onset the unpointed script elicited larger amplitudes than the pointed one with earlier latencies. As this latency has been linked to orthographic-linguistic processing and to the classification of stimuli, it is suggested that these differences are associated with distinct lexical processing of a shallow and a deep orthography.

  16. Socially-mediated differences in brain monoamines in rainbow trout: effects of trace metal contaminants

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    Sloman, Katherine A. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA (United Kingdom)]. E-mail:; Lepage, Olivier [Evolutionary Biology Centre, Department of Comparative Physiology, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden); Rogers, Joseph T. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ont., L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ont., L8S 4K1 (Canada); Winberg, Svante [Evolutionary Biology Centre, Department of Comparative Physiology, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)


    Monoaminergic systems play a crucial role in linking behaviour and physiology. Here the physiological and behavioural effects of metal exposure in relation to monoaminergic systems were considered by exposing rainbow trout dyads, demonstrating stable dominance relationships, to cadmium or lead. Fish exposed to 4 {mu}g l{sup -1} cadmium accumulated more cadmium at the gill than fish held in control water. Fish exposed to 7 {mu}g l{sup -1} cadmium had higher gill, liver and kidney cadmium concentrations. No significant lead accumulation was seen after exposure to 46 {mu}g l{sup -1} for 48 h but exposure to 325 {mu}g l{sup -1} lead caused an increase in gill, liver and kidney lead concentrations. Brain accumulation of both cadmium and lead was only seen after exposure to the highest concentrations. Exposure to 4 or 7 {mu}g l{sup -1} cadmium, or 46 or 325 {mu}g l{sup -1} lead for 48 h did not disrupt established dominance hierarchies. As expected with this stable behavioural situation, in control pairs, animals of different social status displayed different physiological profiles. Subordinate fish had higher concentrations of circulating plasma cortisol and telencephalic 5-hydroxyindoleacetic acid/5-hydroxytryptamine (serotonin) (5-HIAA/5-HT) ratios. However, these physiological profiles were affected by metal exposure, with a trend towards higher serotonergic activity in dominant fish. Dominants exposed to 325 {mu}g l{sup -1} lead had significantly higher hypothalamic 5-HIAA/5-HT ratios when compared with subordinates. The results demonstrate that if stable social hierarchies are established in control water they may not be affected by exposure to cadmium and lead although physiological changes may be evident.

  17. Brain regional differences in CB1 receptor adaptation and regulation of transcription


    Lazenka, M.F.; Selley, D.E.; Sim-Selley, L J


    Cannabinoid CB1 receptors (CB1Rs) are expressed throughout the brain and mediate the central effects of cannabinoids, including Δ9-tetrahydrocannabinol (THC), the main psychoactive constituent of marijuana. Repeated THC administration produces tolerance to cannabinoid-mediated effects, although the magnitude of tolerance varies by effect. Consistent with this observation, CB1R desensitization and downregulation, as well induction of immediate early genes (IEGs), varies by brain region. Zif268...

  18. Understanding actions of others: the electrodynamics of the left and right hemispheres. A high-density EEG neuroimaging study.

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    Stephanie Ortigue

    Full Text Available BACKGROUND: When we observe an individual performing a motor act (e.g. grasping a cup we get two types of information on the basis of how the motor act is done and the context: what the agent is doing (i.e. grasping and the intention underlying it (i.e. grasping for drinking. Here we examined the temporal dynamics of the brain activations that follow the observation of a motor act and underlie the observer's capacity to understand what the agent is doing and why. METHODOLOGY/PRINCIPAL FINDINGS: Volunteers were presented with two-frame video-clips. The first frame (T0 showed an object with or without context; the second frame (T1 showed a hand interacting with the object. The volunteers were instructed to understand the intention of the observed actions while their brain activity was recorded with a high-density 128-channel EEG system. Visual event-related potentials (VEPs were recorded time-locked with the frame showing the hand-object interaction (T1. The data were analyzed by using electrical neuroimaging, which combines a cluster analysis performed on the group-averaged VEPs with the localization of t