The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Pascale Mazzolapomietto - One of the best experts on this subject based on the ideXlab platform.
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blunted activation in right ventrolateral prefrontal cortex during motor response inhibition in Schizophrenia
Schizophrenia Research, 2007Co-Authors: A Kaladjian, Stephan Grimault, Jeanluc Anton, José M. Azorín, Regine Jeanningros, Pascale MazzolapomiettoAbstract:Abstract Objectives Previous functional magnetic resonance imaging (fMRI) studies have reported abnormal brain activation in individuals with Schizophrenia during performance of motor inhibition tasks. We aimed to clarify brain functional abnormalities related to motor response inhibition in Schizophrenia by using event-related fMRI in combination with a Go–NoGo task designed to control for non-inhibitory cognitive processes involved in task performance. Method We studied 21 schizophrenic patients and 21 healthy subjects, group-matched for age, sex, and performance accuracy on a Go–NoGo task during event-related fMRI. The task was designed so that Go and NoGo events were equally probable. Between-group activation differences were assessed using ANCOVAs with response time and IQ as covariates of non-interest. Results Compared to healthy subjects, schizophrenic patients exhibited a significant decrease in activation during motor response inhibition in the right ventrolateral prefrontal cortex (VLPFC) only. There were no areas of increased brain activation in patients compared to healthy subjects. Conclusions Schizophrenic patients demonstrate a blunted activation in the right VLPFC, a region known to play a critical role in motor response inhibition. Further research should ascertain the contribution of the VLPFC dysfunction to the impulsive behavior observed in Schizophrenia.
Shinichi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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pseudoautosomal region in Schizophrenia sex concordance of the affected sibpairs and the association study with dna markers
American Journal of Medical Genetics, 1993Co-Authors: Toru Ishida, Hiroshi Yoneda, Yasuhiro Nonomura, Yasuhiro Inayama, Yoshihiro Kono, T. Sakai, Shinichi KobayashiAbstract:To test a hypothesis that the pseudoautosomal region of the sex chromosomes contributes to the pathogenesis of Schizophrenia, we carried out the following studies: First, the sex concordant rates of 77 schizophrenic sibpairs were examined. Secondly, 46 schizophrenic patients and 150 healthy controls were tested for association with DXYS17, DXYS20, DXYS28, and MIC2 in the pseudoautosomal region. Sex concordant rates in sibpairs with Schizophrenia were not higher than would be expected by chance. No significant associations were found between four DNA markers we tested and Schizophrenia. These results did not support the hypothesis; however, linkage disequilibrium can only be detected if the marker and trait loci are located close enough. Linkage analyses in multiplex families need to be carried out before ruling out this region as a location for a gene for Schizophrenia. © 1993 Wiley-Liss, Inc.
A Kaladjian - One of the best experts on this subject based on the ideXlab platform.
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blunted activation in right ventrolateral prefrontal cortex during motor response inhibition in Schizophrenia
Schizophrenia Research, 2007Co-Authors: A Kaladjian, Stephan Grimault, Jeanluc Anton, José M. Azorín, Regine Jeanningros, Pascale MazzolapomiettoAbstract:Abstract Objectives Previous functional magnetic resonance imaging (fMRI) studies have reported abnormal brain activation in individuals with Schizophrenia during performance of motor inhibition tasks. We aimed to clarify brain functional abnormalities related to motor response inhibition in Schizophrenia by using event-related fMRI in combination with a Go–NoGo task designed to control for non-inhibitory cognitive processes involved in task performance. Method We studied 21 schizophrenic patients and 21 healthy subjects, group-matched for age, sex, and performance accuracy on a Go–NoGo task during event-related fMRI. The task was designed so that Go and NoGo events were equally probable. Between-group activation differences were assessed using ANCOVAs with response time and IQ as covariates of non-interest. Results Compared to healthy subjects, schizophrenic patients exhibited a significant decrease in activation during motor response inhibition in the right ventrolateral prefrontal cortex (VLPFC) only. There were no areas of increased brain activation in patients compared to healthy subjects. Conclusions Schizophrenic patients demonstrate a blunted activation in the right VLPFC, a region known to play a critical role in motor response inhibition. Further research should ascertain the contribution of the VLPFC dysfunction to the impulsive behavior observed in Schizophrenia.
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Blunted activation in right ventrolateral prefrontal cortex during motor response inhibition in Schizophrenia.
Schizophrenia research, 2007Co-Authors: A Kaladjian, Stephan Grimault, Jeanluc Anton, José M. Azorín, Regine Jeanningros, Pascale Mazzola-pomiettoAbstract:Previous functional magnetic resonance imaging (fMRI) studies have reported abnormal brain activation in individuals with Schizophrenia during performance of motor inhibition tasks. We aimed to clarify brain functional abnormalities related to motor response inhibition in Schizophrenia by using event-related fMRI in combination with a Go-NoGo task designed to control for non-inhibitory cognitive processes involved in task performance. We studied 21 schizophrenic patients and 21 healthy subjects, group-matched for age, sex, and performance accuracy on a Go-NoGo task during event-related fMRI. The task was designed so that Go and NoGo events were equally probable. Between-group activation differences were assessed using ANCOVAs with response time and IQ as covariates of non-interest. Compared to healthy subjects, schizophrenic patients exhibited a significant decrease in activation during motor response inhibition in the right ventrolateral prefrontal cortex (VLPFC) only. There were no areas of increased brain activation in patients compared to healthy subjects. Schizophrenic patients demonstrate a blunted activation in the right VLPFC, a region known to play a critical role in motor response inhibition. Further research should ascertain the contribution of the VLPFC dysfunction to the impulsive behavior observed in Schizophrenia.
Toshiya Murai - One of the best experts on this subject based on the ideXlab platform.
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anterior cingulate pathology and social cognition in Schizophrenia a study of gray matter white matter and sulcal morphometry
NeuroImage, 2007Co-Authors: Hironobu Fujiwara, Makiko Yamada, Kazuyuki Hirao, Chihiro Namiki, Hidenao Fukuyama, Takuji Hayashi, Mitsuaki Shimizu, Toshiya MuraiAbstract:Abstract The anterior cingulate gyrus (ACG) is a critical structure for social cognitive processing; the pathology of this structure might be a major source of social dysfunction in Schizophrenia. Multiple structural abnormalities of the ACG have been demonstrated in Schizophrenia including changes in gray matter volume, white matter microstructures and macroscopic sulcal morphology. However, the interrelationships among these different abnormalities have not been investigated. Thus, the relationship between structural abnormalities in the ACG and social cognition in Schizophrenia remains to be elucidated. Magnetic resonance imaging data were acquired at 3.0 T from 26 schizophrenic patients and 20 healthy participants. We performed anterior cingulate cortex (ACC) volumetry, evaluated diffusion tensor imaging of the anterior cingulum, analyzed paracingulate/cingulate sulcus (PCS/CS) morphology and investigated the interrelationships among these measures. We also investigated the association between ACG structural abnormalities and psychopathology, and the social cognition ability of schizophrenic patients as estimated by emotion attribution tasks. Compared with healthy subjects, schizophrenic patients exhibited reduced ACC volume, decreased fractional anisotropy in the anterior cingulum bilaterally and a poorly developed PCS/CS in the left hemisphere. No interrelationship was identified among these measures in the schizophrenic group. Schizophrenic patients performed poorly on emotion attribution tasks. Importantly, clinical symptoms and performance on emotion attribution subtasks were associated with ACC volumes and left PCS/CS variation in different ways. These results suggested that pathology of the ACC, anterior cingulum and PCS/CS is, at least partially, independent and has differential impacts on psychopathology and social cognitive impairment in Schizophrenia.
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Social cognition and frontal lobe pathology in Schizophrenia: a voxel-based morphometric study.
NeuroImage, 2007Co-Authors: Makiko Yamada, Kazuyuki Hirao, Chihiro Namiki, Takashi Hanakawa, Hidenao Fukuyama, Takuji Hayashi, Toshiya MuraiAbstract:Abstract Impaired social cognition in Schizophrenia is considered as the core contributor in the poor psychosocial functioning of schizophrenic patients. In this study, in order to better understand the neurobiological processes underlying social dysfunction in Schizophrenia, we investigated regional structural brain abnormalities and emotion-attribution abilities in these patients. Twenty schizophrenic patients and 20 group-matched healthy comparison participants underwent magnetic resonance imaging (MRI) and were examined for emotion-attribution abilities by using the Perception of Affect Task (PAT). Voxel-based morphometry (VBM) was applied to investigate regional brain structural alterations. Relative to the healthy participants, the schizophrenic patients exhibited reduced gray matter concentrations in the left superior temporal gyrus, the medial prefrontal cortex (MPFC), right anterior cingulate gyrus, bilateral ventrolateral prefrontal cortex, and right insula. The schizophrenic patients performed poorly on emotion-attribution tasks. Importantly, poor performance on emotion attribution to protagonists in social situations was found to be associated with reductions in gray matter in the MPFC of the patient group. This preliminary result suggests that in Schizophrenia, difficulties in understanding the emotional experiences of others are possible manifestations of structural abnormalities in the MPFC. This study provides the neurobiological correlates of social dysfunction in Schizophrenia and links structural abnormalities with impaired social cognitive abilities.
Toru Ishida - One of the best experts on this subject based on the ideXlab platform.
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pseudoautosomal region in Schizophrenia sex concordance of the affected sibpairs and the association study with dna markers
American Journal of Medical Genetics, 1993Co-Authors: Toru Ishida, Hiroshi Yoneda, Yasuhiro Nonomura, Yasuhiro Inayama, Yoshihiro Kono, T. Sakai, Shinichi KobayashiAbstract:To test a hypothesis that the pseudoautosomal region of the sex chromosomes contributes to the pathogenesis of Schizophrenia, we carried out the following studies: First, the sex concordant rates of 77 schizophrenic sibpairs were examined. Secondly, 46 schizophrenic patients and 150 healthy controls were tested for association with DXYS17, DXYS20, DXYS28, and MIC2 in the pseudoautosomal region. Sex concordant rates in sibpairs with Schizophrenia were not higher than would be expected by chance. No significant associations were found between four DNA markers we tested and Schizophrenia. These results did not support the hypothesis; however, linkage disequilibrium can only be detected if the marker and trait loci are located close enough. Linkage analyses in multiplex families need to be carried out before ruling out this region as a location for a gene for Schizophrenia. © 1993 Wiley-Liss, Inc.
