Corpus callosum area and functioning in schizophrenic patients with auditory–verbal hallucinations (original) (raw)
Related papers
Corpus callosum size and inter-hemispheric function in schizophrenia
Schizophrenia …, 1997
We studied the relationship between corpus callosum area and both inter-hemispheric facilitation and interference in schizophrenics and controls. Mid-sagittal sections through the corpus callosum were measured using structural magnetic resonance imaging on 42 patients and 43 normal controls, along with symptom profiles. In a sub-sample, a modified version of the Stroop Test was also performed (27 patients and 29 controls) to assess inter-hemispheric facilitation and interference of colour naming. In the larger sample (total subjects, n = 85), there were no significant differences between patients and controls in CC area but a trend towards smaller values in patients in all but the posterior segment. In the sub-sample, bilateral facilitation was greater, and interference, less in schizophrenics compared with controls. There was a positive correlation between facilitation and posterior CC area, parallelled by a negative correlation between interference and posterior CC area, in both patients and controls, which only reached statistical significance when both groups were combined. These findings suggest that the link, between CC size and neuropsychological processes involving inter-hemispheric transfer of information, is common to both schizophrenics and normal controls. There were significant negative correlations between anterior CC area and psychomotor poverty (avolition, anhedonia and affective flattening), and a suggestion that the negative correlation between age and CC size in controls was not present in patients.
Hallucinatory disorder, an original clinical picture? Clinical and imaging data
Progress in Neuro-Psychopharmacology and Biological Psychiatry, 2008
The aim of this study was to verify the existence of areas of clinical and neurofunctional homogeneity in a group of patients with auditory verbal hallucinations (AVHs) as an isolated symptom, attributable to what we have called "Hallucinatory Disorder" (HD) in an attempt to propose a clinical picture that is distinct from Schizophrenia. Nine patients clinically characterised by chronic AVHs were compared with nine schizophrenic patients using the Structured Clinical Interview for DSM-III-R, BPRS, PANSS, SAPS, SANS, HRS-A, HRS-D, CDSS, MMSE, CGI and PSYRATS. Both groups of patients and nine healthy subjects underwent EEG and SPECT examinations. Considering the psychopathological dimensions of Schizophrenia, in the HD patients clinical evaluations revealed a mono-dimensional clinical profile, whereas all these dimensions contributed to the clinical picture of the schizophrenic patients. The SPECT data showed that the schizophrenic patients had a reduced rCBF in some areas of the right frontal lobe, while the HD patients did not show any area of hypoperfusion. The SPECT hyperperfusion data showed an activation pattern in the HD patients that was characterised by the involvement of various cortical and subcortical cerebral areas, similar to those found in studies of inner speech and auditory verbal imagery. The two groups of patients present significant differences that seem capable of supporting the proposed hypothesis that HD may be an independent nosographical entity.
Structural covariance in the hallucinating brain: a voxel-based morphometry study
Journal of psychiatry …, 2009
Background: Neuroimaging studies have indicated that a number of cortical regions express altered patterns of structural covariance in schizophrenia. The relation between these alterations and specific psychotic symptoms is yet to be investigated. We used voxel-based morphometry to examine regional grey matter volumes and structural covariance associated with severity of auditory verbal hallucinations. Methods: We applied optimized voxel-based morphometry to volumetric magnetic resonance imaging data from 26 patients with medication-resistant auditory verbal hallucinations (AVHs); statistical inferences were made at p < 0.05 after correction for multiple comparisons. Results: Grey matter volume in the left inferior frontal gyrus was positively correlated with severity of AVHs. Hallucination severity influenced the pattern of structural covariance between this region and the left superior/middle temporal gyri, the right inferior frontal gyrus and hippocampus, and the insula bilaterally. Limitations: The results are based on self-reported severity of auditory hallucinations. Complementing with a clinician-based instrument could have made the findings more compelling. Future studies would benefit from including a measure to control for other symptoms that may covary with AVHs and for the effects of antipsychotic medication.
Shape and size of the corpus callosum in schizophrenia and schizotypal personality disorder
Schizophrenia …, 2000
The size and shape of the corpus callosum were assessed on sagittal section magnetic resonance images in 27 patients with schizophrenia, 13 patients with schizotypal personality disorder (SPD), and 30 healthy volunteers. High-resolution 1.2 mm axial SPGR images were acquired and resectioned so that the sagittal plane passed through the anterior and posterior commissures and was parallel to the interhemispheric fissure. The corpus callosum and the whole brain were traced on midsagittal section slices of each brain, and the callosum was divided into 30 anteroposterior sectors. Pixel-by-pixel chi-square and thin-plate spline analyses were used to assess between-group shape differences. Size of the corpus callosum was smaller anteriorly in the genu of the corpus callosum and posteriorly in the splenium in schizophrenic patients than in normal controls. The genu of the corpus callosum was larger in SPD patients than in schizophrenic patients or normal controls. The posterior corpus callosum was largest in normal controls, smaller in SPD patients, and smallest in schizophrenic patients. Shape analysis was consistent with these size comparisons, and suggested a downward bowing of the corpus callosum in schizophrenic and SPD patients. SPD patients also had a region of the callosum just posterior to the genu that was narrower than in the other two groups. The decreases in corpus callosal size in schizophrenia varied directly with length of illness, perhaps indicative of a progressive process. The patient–control differences in callosal size and shape are consistent with a hypothesis of decreased connectivity between the left and the right hemispheres in schizophrenia and SPD.
South African journal of psychiatry, 2014
The corpus callosum (CC) is known to be the largest white-matter fibre tract in the brain. It connects the two cerebral hemispheres and facilitates interhemispheric communication. [1,2] The CC has been strongly implicated as an anatomical mediator of dysfunctional interhemispheric transfer in schizophrenia [3] and a number of psychiatric disorders, including bipolar affective disorder, depression, [4] antisocial personality disorder, [5] post-traumatic stress disorder, [6] autism [7] and attention deficit hyperactivity disorder. [8] Rosenthal and Bigelow [9] first drew attention to an increased thickness of the CC in postmortem brains of schizophrenia patients. Later, in neuroimaging studies, CC size was found to be increased, [10] decreased [11] or unaltered [12] compared with healthy controls. In a meta-analysis of 28 magnetic resonance imaging (MRI) studies carried out by Arnone et al., [13] they found that schizophrenia patients seem to show a reduction in CC area. [13] The inconsistent findings may be a consequence of possible confounding factors, including age, [14] handedness, [15] gender, [16] chronicity of illness [17,18] and differences in CC partitioning schemes employed by the different studies. [19,20] In addition, it was suggested that it may also be owing to the heterogeneity in symptom profiles. [12,18] Schizophrenia is characterised by large heterogeneity, [12,18] and subtypes of schizophrenia may differ in neuroimaging-based measures of brain morphology. [21] Therefore, we planned to examine CC size on the basis of clinical subtype in schizophrenia, and we recruited the four subtypes of schizophrenia patients (paranoid, disorganised, undifferentiated and residual) who had different illness durations but were matched in age, sex and handedness. We hypothesised that the size of the CC may be different in the different subtypes of schizophrenia. Objective The objective of the current MRI study was to determine whether there were any differences in length and area of the CC among schizophrenia subtype patients and healthy subjects. Examining the association between schizophrenia subtypes and the size of the CC is likely to deepen our understanding of the pathophysiology of schizophrenia.
Corpus callosum in schizophrenia with deficit and non-deficit syndrome: a statistical shape analysis
General Psychiatry, 2021
Background The corpus callosum (CC) is the most targeted region in the cerebrum that integrates cognitive data between homologous areas in the right and left hemispheres. Aims Our study used statistical analysis to determine whether there was a correlation between shape changes in the CC in patients with schizophrenia (SZ) (deficit syndrome (DS) and non-deficit syndrome (NDS)) and healthy control (HC) subjects. Methods This study consisted of 27 HC subjects and 50 schizophrenic patients (20 with DS and 30 with NDS). 3 patients with DS and 4 patients with NDS were excluded. Three-dimensional, sagittal, T1-spoiled, gradient-echo imaging was used. Standard anatomical landmarks were selected and marked on each image using specific software. Results As to comparing the Procrustes mean shapes of the CC, statistically significant differences were observed between HC and SZ (DS+NDS) (p=0.017, James’s Fj=73.732), HC and DS (p<0.001, James’s Fj=140.843), HC and NDS (p=0.006, James’s Fj=89....
Scientific reports, 2015
Studies comparing gray matter (GM) volume of schizophrenic patients with or without auditory verbal hallucinations (AVHs) to that of normal controls remain controversial. This project aims to investigate changes of GM volumes of drug-naïve schizophrenic patients with and without AVHs. Eighteen first episode schizophrenic (FES) patients with AVHs, 18 FES patients without AVHs, and 18 healthy controls were scanned using structural MRI. Voxel-based morphometry (VBM) analysis was conducted to investigate changes of GM volume among the three groups. Patients with and without AVHs exhibited reduced GM volumes relative to normal controls in the left superior temporal gyrus, frontal regions, cerebellum and caudate. Further analysis of the GM of subcortical structures found that patients with AVHs had reduced thalamic volume than healthy controls. No significant difference was found between patients with and without AVHs. Significant correlation was found between the total scores of the Posi...