Reduced Cortical Folding in Schizophrenia: An MRI Morphometric Study

Approximately 30% of individuals with 22q11.2 Deletion Syndrome (22q11DS) develop schizophrenia during adolescence/early adulthood, making this syndrome a model for the disorder. Furthermore, negative symptoms exist in up to 80% of patients diagnosed with 22q11DS. The present study aims to uncover morphological brain alterations associated with negative symptoms in a cohort of patients with 22q11DS who are at-risk for developing schizophrenia. A total of 71 patients with 22q11DS aged 12 to 35 (54% females) with no past or present diagnosis of a schizophrenia were included in the study. Psychotic symptom scores were used to divide patients into subgroups by means of a cluster analysis. Three major subgroups were evident: patients with low negative and positive symptoms; patients with high negative symptoms and low positive symptoms; and patients with high negative and positive symptoms. Cortical volume, thickness and gyrification were compared between subgroups using FreeSurfer software. Results showed that patients with high negative symptoms, compared to those with low negative symptoms, have decreased gyrification in the medial occipito-temporal (MOT) and lateral temporo-parietal (LTP) cortices of the left hemisphere, and in the medial temporal (MT)/posterior cingulate (PCC) cortices of the right hemisphere. These findings suggest that high negative symptoms are associated with gyrification reductions predominantly in medial occipital and temporal regions, which are areas implicated in social cognition and early visual processing. Furthermore, as cortical folding develops in utero and during the first years of life, reduced gyrification may represent an early biomarker predicting the development of negative symptoms.

Section: Introductionmentioning

confidence: 78%

Morphological brain changes associated with negative symptoms in patients with 22q11.2 Deletion Syndrome

Mihailov

Padula

Scariati

et al. 2017

“…Both reduced (e.g. Sallet et al, 2003) and increased (e.g. Falkai et al, 2007) GI have been found using manual or automated methods on coronal sections of MR images, and one study did not find significant group differences (Highley et al, 2003).…”

Section: Introductionmentioning

confidence: 98%

Reduced brain cortical folding in schizophrenia revealed in two independent samples

Nesvåg

Schaer

Haukvik

et al. 2014

The cerebral cortex is highly convoluted, and principal folding patterns are determined early in life. Degree of cortical folding in adult life may index aberrations in brain development. Results from previous studies of cortical folding in schizophrenia are inconsistent. Here we investigated cortical folding patterns in the hitherto largest sample of patients with schizophrenia drawn from two independent cohorts. Magnetic resonance imaging scans were acquired from 207 patients and 206 healthy subjects recruited to two separate research projects in Sweden and Norway. Local gyrification index (lGI) was estimated continuously across the cortex using automated methods. Group differences in lGI were analyzed using general linear models. Patients had lower lGI in three large clusters of the cortex with peak differences found in the left precentral gyrus, right middle temporal gyrus, and right precuneus. Similar, although not completely overlapping results were found when the two cohorts were analyzed separately. There were no significant interaction effects between age and diagnosis and gender and diagnosis. The finding of reduced degree of folding in large regions of the cerebral cortex across two independent samples indicates that reduced gyrification is an inherent feature of the brain pathology in schizophrenia.

“…Cortical folding abnormalities in schizophrenia measured using the gyrification index (GI) methodology (Zilles et al, 1988) have been reported in post-mortem (Vogeley et al, 2000) and MRI studies (Harris et al, 2004a;Harris et al, 2004b;Kulynych et al, 1997;Sallet et al, 2003). Since the GI measures the ratio of inner and outer cortical surface contours, these studies were limited to analyses of brain slices in different lobes.…”

Section: Introductionmentioning

confidence: 99%

Abnormal cortical folding patterns within Broca's area in schizophrenia: Evidence from structural MRI

Wisco¹,

Kuperberg²,

Manoach³

et al. 2007

We compared cortical folding patterns between patients with schizophrenia and demographicallymatched healthy controls in prefrontal and temporal regions of interest. Using the Freesurfer (http:// surfer.nmr.mgh.harvard.edu) cortical surface-based reconstruction methodology, we indirectly ascertained cortical displacement and convolution, together, by measuring the degree of metric distortion required to optimally register cortical folding patterns to an average template. An area within the pars triangularis of the left inferior frontal gyrus (Broca's area) showed significantly reduced metric distortion in the patient group relative to the control group (p = 0.0352). We discuss these findings in relation to the neurodevelopmental hypothesis and language dysfunction in schizophrenia.