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Masayoshi Kurachi - One of the best experts on this subject based on the ideXlab platform.
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A follow-up MRI study of the Fusiform Gyrus and middle and inferior temporal gyri in schizophrenia spectrum.
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2011Co-Authors: Tsutomu Takahashi, Shi-yu Zhou, Kazue Nakamura, Ryoichiro Tanino, Atsushi Furuichi, Mikio Kido, Yasuhiro Kawasaki, Kyo Noguchi, Hikaru Seto, Masayoshi KurachiAbstract:Abstract While longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive gray matter reduction of the superior temporal Gyrus (STG) during the early phases of schizophrenia, it remains largely unknown whether other temporal lobe structures also exhibit similar progressive changes and whether these changes, if present, are specific to schizophrenia among the spectrum disorders. In this longitudinal MRI study, the gray matter volumes of the Fusiform, middle temporal, and inferior temporal gyri were measured at baseline and follow-up scans (mean inter-scan interval = 2.7 years) in 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. Both schizophrenia and schizotypal patients had a smaller Fusiform Gyrus than controls bilaterally at both time points, whereas no group difference was found in the middle and inferior temporal gyri. In the longitudinal comparison, the schizophrenia patients showed significant Fusiform Gyrus reduction (left, − 2.6%/year; right, − 2.3%/year) compared with schizotypal patients (left: − 0.4%/year; right: − 0.2%/year) and controls (left: 0.1%/year; right: 0.0%/year). However, the middle and inferior temporal gyri did not exhibit significant progressive gray matter change in all diagnostic groups. In the schizophrenia patients, a higher cumulative dose of antipsychotics during follow-up was significantly correlated with less severe gray matter reduction in the left Fusiform Gyrus. The annual gray matter loss of the Fusiform Gyrus did not correlate with that of the STG previously reported in the same subjects. Our findings suggest regional specificity of the progressive gray matter reduction in the temporal lobe structures, which might be specific to overt schizophrenia within the schizophrenia spectrum.
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temporal lobe gray matter in schizophrenia spectrum a volumetric mri study of the Fusiform Gyrus parahippocampal Gyrus and middle and inferior temporal gyri
Schizophrenia Research, 2006Co-Authors: Tsutomu Takahashi, Shi-yu Zhou, Ryoichiro Tanino, Yasuhiro Kawasaki, Hikaru Seto, Michio Suzuki, Hirofumi Hagino, Masayoshi KurachiAbstract:Abstract Although several brain morphologic studies have suggested abnormalities in the temporal regions to be a common indicator of vulnerability for the schizophrenia spectrum, less attention has been paid to temporal lobe structures other than the superior temporal Gyrus or the medial temporal region. In this study, we investigated the volume of gray matter in the Fusiform Gyrus, the parahippocampal Gyrus, the middle temporal Gyrus, and the inferior temporal Gyrus using magnetic resonance imaging in 39 schizotypal disorder patients, 65 schizophrenia patients, and 72 age and gender matched healthy control subjects. The anterior Fusiform Gyrus was significantly smaller in the schizophrenia patients than the control subjects but not in the schizotypal disorder patients, while the volume reduction of the posterior Fusiform Gyrus was common to both disorders. Volumes for the middle and inferior temporal gyri or the parahippocampal Gyrus did not differ between groups. These findings suggest that abnormalities in the posterior region of the Fusiform Gyrus are, as have been suggested for the superior temporal Gyrus or the amygdala/hippocampus, prominent among the temporal lobe structures as a common morphologic substrate for the schizophrenia spectrum, whereas more widespread alterations involving the anterior region might be associated with the development of full-blown schizophrenia.
Shi-yu Zhou - One of the best experts on this subject based on the ideXlab platform.
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A follow-up MRI study of the Fusiform Gyrus and middle and inferior temporal gyri in schizophrenia spectrum.
Progress in Neuro-psychopharmacology & Biological Psychiatry, 2011Co-Authors: Tsutomu Takahashi, Shi-yu Zhou, Kazue Nakamura, Ryoichiro Tanino, Atsushi Furuichi, Mikio Kido, Yasuhiro Kawasaki, Kyo Noguchi, Hikaru Seto, Masayoshi KurachiAbstract:Abstract While longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive gray matter reduction of the superior temporal Gyrus (STG) during the early phases of schizophrenia, it remains largely unknown whether other temporal lobe structures also exhibit similar progressive changes and whether these changes, if present, are specific to schizophrenia among the spectrum disorders. In this longitudinal MRI study, the gray matter volumes of the Fusiform, middle temporal, and inferior temporal gyri were measured at baseline and follow-up scans (mean inter-scan interval = 2.7 years) in 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. Both schizophrenia and schizotypal patients had a smaller Fusiform Gyrus than controls bilaterally at both time points, whereas no group difference was found in the middle and inferior temporal gyri. In the longitudinal comparison, the schizophrenia patients showed significant Fusiform Gyrus reduction (left, − 2.6%/year; right, − 2.3%/year) compared with schizotypal patients (left: − 0.4%/year; right: − 0.2%/year) and controls (left: 0.1%/year; right: 0.0%/year). However, the middle and inferior temporal gyri did not exhibit significant progressive gray matter change in all diagnostic groups. In the schizophrenia patients, a higher cumulative dose of antipsychotics during follow-up was significantly correlated with less severe gray matter reduction in the left Fusiform Gyrus. The annual gray matter loss of the Fusiform Gyrus did not correlate with that of the STG previously reported in the same subjects. Our findings suggest regional specificity of the progressive gray matter reduction in the temporal lobe structures, which might be specific to overt schizophrenia within the schizophrenia spectrum.
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temporal lobe gray matter in schizophrenia spectrum a volumetric mri study of the Fusiform Gyrus parahippocampal Gyrus and middle and inferior temporal gyri
Schizophrenia Research, 2006Co-Authors: Tsutomu Takahashi, Shi-yu Zhou, Ryoichiro Tanino, Yasuhiro Kawasaki, Hikaru Seto, Michio Suzuki, Hirofumi Hagino, Masayoshi KurachiAbstract:Abstract Although several brain morphologic studies have suggested abnormalities in the temporal regions to be a common indicator of vulnerability for the schizophrenia spectrum, less attention has been paid to temporal lobe structures other than the superior temporal Gyrus or the medial temporal region. In this study, we investigated the volume of gray matter in the Fusiform Gyrus, the parahippocampal Gyrus, the middle temporal Gyrus, and the inferior temporal Gyrus using magnetic resonance imaging in 39 schizotypal disorder patients, 65 schizophrenia patients, and 72 age and gender matched healthy control subjects. The anterior Fusiform Gyrus was significantly smaller in the schizophrenia patients than the control subjects but not in the schizotypal disorder patients, while the volume reduction of the posterior Fusiform Gyrus was common to both disorders. Volumes for the middle and inferior temporal gyri or the parahippocampal Gyrus did not differ between groups. These findings suggest that abnormalities in the posterior region of the Fusiform Gyrus are, as have been suggested for the superior temporal Gyrus or the amygdala/hippocampus, prominent among the temporal lobe structures as a common morphologic substrate for the schizophrenia spectrum, whereas more widespread alterations involving the anterior region might be associated with the development of full-blown schizophrenia.
Timothy J Andrews - One of the best experts on this subject based on the ideXlab platform.
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distinct but overlapping patterns of response to words and faces in the Fusiform Gyrus
Cerebral Cortex, 2016Co-Authors: Richard J Harris, Grace E Rice, Andrew W Young, Timothy J AndrewsAbstract:: Converging evidence suggests that the Fusiform Gyrus is involved in the processing of both faces and words. We used fMRI to investigate the extent to which the representation of words and faces in this region of the brain is based on a common neural representation. In Experiment 1, a univariate analysis revealed regions in the Fusiform Gyrus that were only selective for faces and other regions that were only selective for words. However, we also found regions that showed both word-selective and face-selective responses, particularly in the left hemisphere. We then used a multivariate analysis to measure the pattern of response to faces and words. Despite the overlap in regional responses, we found distinct patterns of response to both faces and words in the left and right Fusiform Gyrus. In Experiment 2, fMR adaptation was used to determine whether information about familiar faces and names is integrated in the Fusiform Gyrus. Distinct regions of the Fusiform Gyrus showed adaptation to either familiar faces or familiar names. However, there was no adaptation to sequences of faces and names with the same identity. Taken together, these results provide evidence for distinct, but overlapping, neural representations for words and faces in the Fusiform Gyrus.
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Activity in the Fusiform Gyrus Predicts Conscious Perception of Rubin's Vase–Face Illusion
NeuroImage, 2002Co-Authors: Timothy J Andrews, Denis Schluppeck, Dave Homfray, Paul M. Matthews, Colin BlakemoreAbstract:We localized regions in the Fusiform Gyrus and superior temporal sulcus that were more active when subjects viewed photographs of real faces than when they viewed complex inanimate objects and other areas in the parahippocampal Gyrus and the lateral occipital lobe that showed more activity during the presentation of nonface objects. Event-related functional magnetic resonance imaging was then used to monitor activity in these extrastriate visual areas while subjects viewed Rubin's vase–face stimulus and indicated switches in perception. Since the spontaneous shifts in interpretation were too rapid for direct correlation with hemodynamic responses, each reported percept (faces or vase) was prolonged by suddenly adding subtle local contrast gradients (embossing) to one side or the other of the figure–ground boundary, stabilizing the percept. Under these conditions, only face-selective areas in the Fusiform Gyrus responded more strongly during the perception of faces. To control for effects of the physical change to Rubin's stimulus (i.e., addition of embossing), we compared activity when the face contours were embossed after the subject had just reported the onset of perception of either faces or vase. Activity in the Fusiform face area responded more strongly under the first condition, despite the fact that the physical stimulus sequences were identical. Moreover, on a trial-to-trial basis, the activity was statistically predictive of the subjects' responses, suggesting that the conscious perception of faces could be made explicit in this extrastriate visual area.
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activity in the Fusiform Gyrus predicts conscious perception of rubin s vase face illusion
NeuroImage, 2002Co-Authors: Timothy J Andrews, Denis Schluppeck, Dave Homfray, Paul M. Matthews, Colin BlakemoreAbstract:We localized regions in the Fusiform Gyrus and superior temporal sulcus that were more active when subjects viewed photographs of real faces than when they viewed complex inanimate objects and other areas in the parahippocampal Gyrus and the lateral occipital lobe that showed more activity during the presentation of nonface objects. Event-related functional magnetic resonance imaging was then used to monitor activity in these extrastriate visual areas while subjects viewed Rubin's vase–face stimulus and indicated switches in perception. Since the spontaneous shifts in interpretation were too rapid for direct correlation with hemodynamic responses, each reported percept (faces or vase) was prolonged by suddenly adding subtle local contrast gradients (embossing) to one side or the other of the figure–ground boundary, stabilizing the percept. Under these conditions, only face-selective areas in the Fusiform Gyrus responded more strongly during the perception of faces. To control for effects of the physical change to Rubin's stimulus (i.e., addition of embossing), we compared activity when the face contours were embossed after the subject had just reported the onset of perception of either faces or vase. Activity in the Fusiform face area responded more strongly under the first condition, despite the fact that the physical stimulus sequences were identical. Moreover, on a trial-to-trial basis, the activity was statistically predictive of the subjects' responses, suggesting that the conscious perception of faces could be made explicit in this extrastriate visual area.
Bruno Rossion - One of the best experts on this subject based on the ideXlab platform.
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Intracerebral electrical stimulation of the right anterior Fusiform Gyrus elicits a transient face-specific impairment in recognizing famous people
Neurophysiologie Clinique-clinical Neurophysiology, 2019Co-Authors: Angélique Volfart, Louis Maillard, Bruno Rossion, Jacques JonasAbstract:Background While the role of posterior temporal regions in face recognition has been largely demonstrated, the importance of the anterior temporal lobe (ATL) is still underestimated, especially because fMRI suffers from a signal dropout in this region. A recent intracranial case study by Jonas et al. (2015) has shown that electrical stimulation of the right anterior Fusiform Gyrus elicited a transient inability to recognize faces. However, because only naming tasks were used, it was hard to distinguish between a face-specific impairment or a naming/semantic deficit. Objectives Here we report the case of a patient (DN) who was implanted with SEEG electrodes in the right ATL. Methods During electrical stimulation, DN was asked to perform famous face and name pointing tasks, which did not require verbal outputs and allowed the direct comparison between two different types of famous stimuli (faces and names). Results Following electrical stimulation of the right anterior Fusiform Gyrus, DN was unable to point the famous face among 2 unfamiliar face distractors. Interestingly, stimulation at these critical contacts did not affect the detection of a famous name among 2 unfamiliar name distractors. Moreover, significant intracerebral face-selective responses and responses to famous faces were found at the critical contacts of stimulation using paradigms of fast periodic visual stimulation. Conclusion Altogether, these findings suggest that the transient inability to recognize famous faces following electrical stimulation of the right anterior Fusiform Gyrus is specific to face stimuli and provide new evidence for the role of this region in familiar face recognition.
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Beyond the core face-processing network: Intracerebral stimulation of a face-selective area in the right anterior Fusiform Gyrus elicits transient prosopagnosia
Cortex, 2015Co-Authors: Jacques Jonas, Bruno Rossion, Hélène Brissart, Solène Frismand, Corentin Jacques, Gabriela Hossu, Sophie Colnat-coulbois, Hervé Vespignani, Jean-pierre Vignal, Louis MaillardAbstract:According to neuropsychological evidence, a distributed network of regions of the ventral visual pathway - from the lateral occipital cortex to the temporal pole - supports face recognition. However, functional magnetic resonance imaging (fMRI) studies have generally confined ventral face-selective areas to the posterior section of the occipito-temporal cortex, i.e., the inferior occipital Gyrus occipital face area (OFA) and the posterior and middle Fusiform Gyrus Fusiform face area (FFA). There is recent evidence that intracranial electrical stimulation of these areas in the right hemisphere elicits face matching and recognition impairments (i.e., prosopagnosia) as well as perceptual face distortions. Here we report a case of transient inability to recognize faces following electrical stimulation of the right anterior Fusiform Gyrus, in a region located anteriorly to the FFA. There was no perceptual face distortion reported during stimulation. Although no fMRI face-selective responses were found in this region due to a severe signal drop-out as in previous studies, intracerebral face-selective event-related potentials and gamma range electrophysiological responses were found at the critical site of stimulation. These results point to a causal role in face recognition of the right anterior Fusiform Gyrus and more generally of face-selective areas located beyond the "core" face-processing network in the right ventral temporal cortex. It also illustrates the diagnostic value of intracerebral electrophysiological recordings and stimulation in understanding the neural basis of face recognition and visual recognition in general.
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face categorization in visual scenes may start in a higher order area of the right Fusiform Gyrus evidence from dynamic visual stimulation in neuroimaging
Journal of Neurophysiology, 2011Co-Authors: Fang Jiang, Laurence Dricot, Rainer Goebel, Jochen Weber, Giulia Righi, Michael J Tarr, Bruno RossionAbstract:How a visual stimulus is initially categorized as a face by the cortical face-processing network remains largely unclear. In this study we used functional MRI to study the dynamics of face detection in visual scenes by using a paradigm in which scenes containing faces or cars are revealed progressively as they emerge from visual noise. Participants were asked to respond as soon as they detected a face or car during the noise sequence. Among the face-sensitive regions identified based on a standard localizer, a high-level face-sensitive area, the right Fusiform face area (FFA), showed the earliest difference between face and car activation. Critically, differential activation in FFA was observed before differential activation in the more posteriorly located occipital face area (OFA). A whole brain analysis confirmed these findings, with a face-sensitive cluster in the right Fusiform Gyrus being the only cluster showing face preference before successful behavioral detection. Overall, these findings indicate that following generic low-level visual analysis, a face stimulus presented in a gradually revealed visual scene is first detected in the right middle Fusiform Gyrus, only after which further processing spreads to a network of cortical and subcortical face-sensitive areas (including the posteriorly located OFA). These results provide further evidence for a nonhierarchical organization of the cortical face-processing network.
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holistic perception of individual faces in the right middle Fusiform Gyrus as evidenced by the composite face illusion
Journal of Vision, 2010Co-Authors: Christine Schiltz, Laurence Dricot, Rainer Goebel, Bruno RossionAbstract:The perception of a facial feature (e.g., the eyes) is influenced by the position and identity of other features (e.g., the mouth) supporting an integrated, or holistic, representation of individual faces in the human brain. Here we used an event-related adaptation paradigm in functional magnetic resonance imaging (fMRI) to clarify the regions representing faces holistically across the whole brain. In each trial, observers performed the same/different task on top halves (aligned or misaligned) of two faces presented sequentially. For each face pair, the identity of top and bottom parts could be both identical, both different, or different only for the bottom half. The latter manipulation resulted in a composite face illusion, i.e., the erroneous perception of identical top parts as being different, only for aligned faces. Release from adaptation in this condition was found in two sub-areas of the right middle Fusiform Gyrus responding preferentially to faces, including the "Fusiform face area" ("FFA"). There were no significant effects in homologous regions of the left hemisphere or in the inferior occipital cortex. Altogether, these observations indicate that face-sensitive populations of neurons in the right middle Fusiform Gyrus are optimally tuned to represent individual exemplars of faces holistically.
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a network of occipito temporal face sensitive areas besides the right middle Fusiform Gyrus is necessary for normal face processing
Brain, 2003Co-Authors: Bruno Rossion, Roberto Caldara, Mohamed L Seghier, Annemarie Schuller, Francois Lazeyras, Eugene MayerAbstract:Neuroimaging studies have identified at least two bilateral areas of the visual extrastriate cortex that respond more to pictures of faces than objects in normal human subjects in the middle Fusiform Gyrus [the 'Fusiform face area' (FFA)] and, more posteriorly, in the inferior occipital cortex ['occipital face area' (OFA)], with a right hemisphere dominance. However, it is not yet clear how these regions interact which each other and whether they are all necessary for normal face perception. It has been proposed that the right hemisphere FFA acts as an isolated ('modular') processing system for faces or that this region receives its face-sensitive inputs from the OFA in a feedforward hierarchical model of face processing. To test these proposals, we report a detailed neuropsychological investigation combined with a neuroimaging study of a patient presenting a deficit restricted to face perception, consecutive to bilateral occipito-temporal lesions. Due to the asymmetry of the lesions, the left middle Fusiform Gyrus and the right inferior occipital cortex were damaged but the right middle Fusiform Gyrus was structurally intact. Using functional MRI, we disclosed a normal activation of the right FFA in response to faces in the patient despite the absence of any feedforward inputs from the right OFA, located in a damaged area of cortex. Together, these findings show that the integrity of the right OFA is necessary for normal face perception and suggest that the face-sensitive responses observed at this level in normal subjects may arise from feedback connections from the right FFA. In agreement with the current literature on the anatomical basis of prosopagnosia, it is suggested that the FFA and OFA in the right hemisphere and their re-entrant integration are necessary for normal face processing.
Robert W Mccarley - One of the best experts on this subject based on the ideXlab platform.
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association between reduced extraversion and right posterior Fusiform Gyrus gray matter reduction in chronic schizophrenia
American Journal of Psychiatry, 2005Co-Authors: Toshiaki Onitsuka, Martha E Shenton, Kiyoto Kasai, Paul G Nestor, Ronald J Gurrera, Melissa Frumin, Margaret A Niznikiewicz, Robert W MccarleyAbstract:OBJECTIVE: The authors examined the association between volume of the Fusiform Gyrus, a region involved in face processing, and the personality trait of extraversion in patients with schizophrenia. METHOD: Male patients (N=24) and age-matched male comparison subjects (N=26) completed NEO Five-Factor Inventory personality measures of extraversion and underwent high-spatial-resolution magnetic resonance imaging of anterior and posterior Fusiform Gyrus gray matter. RESULTS: Low extraversion scores were significantly correlated with gray matter volume reductions in the right posterior Fusiform Gyrus for patients but not comparison subjects. CONCLUSIONS: Reduced right posterior Fusiform Gyrus volume may contribute to disease-related social disturbances, characterized by both low extraversion and reduced sensitivity to human faces.
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a mri study of Fusiform Gyrus in schizotypal personality disorder
Schizophrenia Research, 2003Co-Authors: Chandlee C Dickey, Robert W Mccarley, Melissa Frumin, Margaret A Niznikiewicz, Martina M Voglmaier, Larry J Seidman, Sarah Toner, Susan Demeo, Martha E ShentonAbstract:The Fusiform Gyrus is important for face and object recognition, is abnormal in schizophrenia, but has not been studied in schizotypal personality disorder (SPD). Thin-slice MR images showed no differences, either in right, left or total Fusiform gyri volumes, between subjects with SPD (N=21) and normal controls (N=19). However, there was a correlation between severity of illusions and magical thinking suffered by the SPD subjects and smaller right Fusiform Gyrus volumes. This suggests that future studies may be useful in determining the functional competence of this Gyrus in SPD. D 2003 Elsevier Science B.V. All rights reserved.
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Fusiform Gyrus volume reduction and facial recognition in chronic schizophrenia
Archives of General Psychiatry, 2003Co-Authors: Toshiaki Onitsuka, Martha E Shenton, Kiyoto Kasai, Ron Kikinis, Ferenc A Jolesz, Paul G Nestor, Sarah Toner, Robert W MccarleyAbstract:Background The Fusiform Gyrus (FG), or occipitotemporal Gyrus, is thought to subserve the processing and encoding of faces. Of note, several studies have reported that patients with schizophrenia show deficits in facial processing. It is thus hypothesized that the FG might be one brain region underlying abnormal facial recognition in schizophrenia. The objectives of this study were to determine whether there are abnormalities in gray matter volumes for the anterior and the posterior FG in patients with chronic schizophrenia and to investigate relationships between FG subregions and immediate and delayed memory for faces. Methods Patients were recruited from the Boston VA Healthcare System, Brockton Division, and control subjects were recruited through newspaper advertisement. Study participants included 21 male patients diagnosed as having chronic schizophrenia and 28 male controls. Participants underwent high-spatial-resolution magnetic resonance imaging, and facial recognition memory was evaluated. Main outcome measures included anterior and posterior FG gray matter volumes based on high-spatial-resolution magnetic resonance imaging, a detailed and reliable manual delineation using 3-dimensional information, and correlation coefficients between FG subregions and raw scores on immediate and delayed facial memory derived from the Wechsler Memory Scale III. Results Patients with chronic schizophrenia had overall smaller FG gray matter volumes (10%) than normal controls. Additionally, patients with schizophrenia performed more poorly than normal controls in both immediate and delayed facial memory tests. Moreover, the degree of poor performance on delayed memory for faces was significantly correlated with the degree of bilateral anterior FG reduction in patients with schizophrenia. Conclusion These results suggest that neuroanatomic FG abnormalities underlie at least some of the deficits associated with facial recognition in schizophrenia.
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Fusiform Gyrus volume reduction in first episode schizophrenia a magnetic resonance imaging study
Archives of General Psychiatry, 2002Co-Authors: Martha E Shenton, Dean F Salisbury, Kiyoto Kasai, Toshiaki Onitsuka, Chandlee C Dickey, Deborah A Yurgeluntodd, Ron Kikinis, Ferenc A Jolesz, Robert W MccarleyAbstract:Background The Fusiform Gyrus (occipitotemporal Gyrus) is thought to be critical for face recognition and may possibly be associated with impaired facial recognition and interpretation of facial expression in schizophrenia. of postmortem studies have suggested that Fusiform Gyrus volume is reduced in schizophrenia, but there have been no in vivo structural studies of the Fusiform Gyrus in schizophrenia using magnetic resonance imaging. Methods High–spatial resolution magnetic resonance images were used to measure the gray matter volume of the Fusiform Gyrus in 22 patients with first-episode schizophrenia (first hospitalization), 20 with first-episode affective psychosis(mainly manic), and 24 control subjects. Results Patients with first-episode schizophrenia had overall smaller relative volumes (absolute volume/intracranial contents) of Fusiform Gyrus gray matter compared with controls (9%) and patients with affective psychosis (7%). For the left Fusiform Gyrus, patients with schizophrenia showed an 11% reduction compared with controls and patients with affective psychosis. Right Fusiform Gyrus volume differed in patients with schizophrenia only compared with controls(8%). Conclusion Schizophrenia is associated with a bilateral reduction in Fusiform Gyrus gray matter volume that is evident at the time of first hospitalization and is different from the presentation of affective psychosis.
