Reduced Cortical Folding in Schizophrenia: An MRI Morphometric Study

Faculty of Medicine, University of Sāo Paulo, Rua Dr. Ovidio Pires de Campos s/n, 05403-010 Sāo Paulo SP, Brazil.
American Journal of Psychiatry (Impact Factor: 12.3). 10/2003; 160(9):1606-13. DOI: 10.1176/appi.ajp.160.9.1606
Source: PubMed


Although well documented, regional brain structural abnormalities in schizophrenia are nonspecific, and morphometric parameters show significant overlapping between patients and healthy comparison subjects. An increasing number of studies have focused on supraregional models involving abnormalities of the neuronal circuitry between cortical regions in schizophrenia. The aim of the present study was to investigate cortical folding as an index of the neuronal wiring in different subtypes of schizophrenia.
Magnetic resonance imaging measures of gyrification index in intervals of 3.6 mm along the total cerebral cortex were compared in 40 patients with DSM-IV schizophrenia and 20 healthy subjects. Psychopathology was assessed with the Positive and Negative Syndrome Scale, Brief Psychiatric Rating Scale, and the Negative Symptom Rating Scale.
The schizophrenia patients showed significantly reduced bilateral cortical folding relative to healthy comparison subjects. Such reductions were more pronounced in those with the disorganized subtype and showed an inverse correlation with negative symptoms and a positive correlation with positive symptoms. The paranoid subtype showed reduced cortical folding that was restricted to the left hemisphere.
These results from a larger patient group confirm a previous report of reduced cortical folding in schizophrenia patients. They also suggest a distinct pattern of abnormality between schizophrenia subtypes regarding the process of cerebral lateralization and are in agreement with the neurodevelopmental hypothesis of schizophrenia.

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Available from: Wagner Gattaz, Jun 18, 2014
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    • ", Narr et al. [2004], Harris et al. [2004], Falkai et al. [2007] and Sallet et al. [2003] MRI gyrification Indices Mean increase in gyrification in right prefrontal region in males. Narr et al [2004] found significant increases in cortical folding in the right superior frontal cortex [Harris et al., 2004], in male but not female patients [Narr et al., 2004]; bilateral increase in SCHZ [Falkai et al., 2007] decrease on left [Sallet et al., 2003]. "
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    • "In prematurely delivered human infants, cerebral cortical folding abnormalities have been observed, and premature birth is associated with subsequent behavioral and cognitive deficits that become apparent later in childhood (Dubois et al., 2008). Cortical folding abnormalities have also been identified in individuals with Williams syndrome (Van Essen et al., 2006b) and schizophrenia (Csernansky et al., 2008b; Harris et al., 2004; Sallet et al., 2003). In autistic individuals, anomalous cortical folding is observed when compared to age-matched controls (Hardan et al., 2004; Nordahl et al., 2007), and the effect on folding is related to the severity of the behavioral deficit (Nordahl et al., 2007). "
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    No preview · Article · Mar 2013
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    • "Folding in the ferret has been thoroughly documented in seminal papers by Smart and McSherry [1] [2] and in more recent work based on MR imaging [3] [4] [5] and detailed histology [6]. Abnormal folding patterns in the human brain are associated with severe mental or emotional disorders [7] [8] [9] [10] [11]. Disturbances of cortical folding in humans 4 Author to whom any correspondence should be addressed. "
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