Cortical surface characteristics among offspring of schizophrenia subjects

Abstract

Background-A systematic study of cortical surface parameters in adolescent offspring of schizophrenia subjects before clinical manifestation could clarify neurodevelopmental antecedents of increased genetic risk. We examined these measures obtained on structural magnetic resonance imaging (MRI) scans at baseline and one year on a series of offspring and healthy subjects.Methods-We measured cortical surface area, curvature and thickness using BRAINS2 on structural MRI scans acquired using 1.5T GE whole body scanner on all subjects. We examined the differences between study groups at baseline using mixed effects models, and longitudinal trajectory of these measures using linear mixed effects models.Results-At baseline, offspring of schizophrenia parents showed reduced gyral surface area in the fronto-parietal lobes along with increased sulcal curvature and parietal gyral cortical thinning compared to healthy subjects. Prospective follow up of these subjects for one year showed shrinking of the total surface area, especially in the bilateral frontal and occipital regions along with preservation of cortical thickness among offspring of schizophrenia parents whereas healthy subjects showed preserved or increased surface area and cortical thinning. Correlation of these measures with lobar volumes were not observed at baseline cross-sectional comparisons but were observed in longitudinal examinations.Discussion-Our observations suggest that adolescents with genetically elevated risk for schizophrenia show altered cortical surface measures affecting cortical surface area and thickness differentially suggesting a divergent trajectory of neurodevelopment. Cortical surface measures appear to be more sensitive to genetic liability to schizophrenia compared to volumetric measures.

Neurological Soft Signs and Brainstem Morphology in First-Episode Schizophrenia

“…Apart from deficient myelination, potential pathological mechanisms could include changes of water content in myelin, increased MR-visible axonal cytosol resulting from alterations in the microtubular density of axons, and neuronal degeneration, amongst others [62]. A previous study on adolescents at risk for schizophrenia suggested cortical volumetric, shape and thickness measures as parameters that are differentially linked to neurodevelopmental processes [63]. However, the cortical gyration is hardly comparable to the morphology of the brainstem.…”

Investigating relationships between cortical thickness and cognitive performance in patients with schizophrenia and healthy adults

“…Thus, cortical thickness and surface area are products of two welldifferentiated ontogenetic processes and the two parameters can therefore separately be affected by genetic defects or extrinsic factors . One study on adolescent first-degree relatives of schizophrenia patients demonstrated reduction in surface area, along with only a slight increase in cortical thickness in a one-year followup study, suggesting different neurodevelopmental trajectories (Prasad et al, 2010).…”

Neural activity changes in unaffected children of patients with schizophrenia: A resting-state fMRI study

“…Structural MRI has shown that the children of schizophrenia patients display some cortical and subcortical brain abnormalities in regions such as the fronto-parietal lobes (Prasad et al, 2010), superior temporal gyrus (Rajarethinam et al, 2004), caudate (Rajarethinam et al, 2007), and the amygdala and hippocampus (Keshavan et al, 2002). Functional imaging studies, including positron emission tomography (PET) and task-based blood oxygenation level dependent (BOLD) functional MRI (t-fMRI) have also been used to explore brain activity alterations in relatives of schizophrenia patients.…”