Increased Frontal Gyrification Negatively Correlates with Executive Function in Patients with First-Episode Schizophrenia

Previous neuroimaging studies of gyrification, a possible marker of early neurodevelopment, in schizophrenia patients have reported inconsistent results. In addition, it remains unclear whether aberrant gyrification in schizophrenia patients, if present, is associated with cognitive impairment, which is one of the core features of schizophrenia. Magnetic resonance images were obtained from 62 patients with first-episode schizophrenia and 57 healthy control subjects. Using FreeSurfer software, local gyrification index (LGI) of the entire cortex was compared between the groups. The relationship between LGI and performance in the Wisconsin Card Sorting Test (WCST) was also examined in a subgroup of patients (n= 28). Compared with the controls, the patients showed a significantly higher LGI in a wide range of bilateral frontal regions as well as in the right inferior parietal and bilateral occipital regions. The number of WCST categories archived in patients was negatively correlated with the LGI mainly in the rostral middle frontal and anterior cingulate regions in the right hemisphere. Our findings suggested a widespread hypergyrification pattern in schizophrenia patients, which supported early neurodevelopmental abnormalities. Our results also suggested that executive dysfunction in schizophrenia patients may be at least partly related to aberrant neurodevelopment, especially in the right frontal regions.