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

Previous neuroimaging studies have suggested that individuals at risk for schizophrenia exhibit structural and functional brain abnormalities. However, few studies focus on resting state baseline activity in individuals with genetic high-risk for schizophrenia (HR). We examined cerebral spontaneous neural activity in HR by measuring the amplitude of low frequency fluctuations (ALFF) in the blood oxygen level-dependent (BOLD) functional magnetic resonance signal during resting state. Using a 3T MRI scanner, 28 non-psychotic young adult participants with at least one parent with schizophrenia and 44 matched unrelated healthy comparison subjects (HC) were scanned during the resting-state. The ALFF of the BOLD signal for each participant was calculated, and these values were then compared between-groups using voxel-based analysis of the ALFF maps. The HR group showed significantly increased ALFF compared to the HC group in the striatum, including the left caudate nucleus extending to the putamen and the right caudate nucleus. There was also increased ALFF in HR relative to controls in the left medial temporal region including hippocampus, parahippocampal gyrus and the fusiform gyrus, as well as regions including the left lateral thalamus, bilateral ventral and dorsal anterior cingulate cortex, bilateral calcarine sulcus and precuneus. There was significantly decreased ALFF in the HR group relative to controls in the left inferior parietal lobule/postcentral gyrus. Our findings suggest that altered intrinsic neuronal activity in cortico-striato-thalamic networks may represent genetic vulnerability for the development of schizophrenia.