Recent studies in healthy populations have shown a hierarchical network of brain areas to process information over time. Specifically, we revealed that the capacity to accumulate information changes gradually from the early sensory areas toward high-order perceptual and cognitive areas. Previous research in schizophrenia pointed to impairment in comprehension of information. Yet, the neural mechanisms underlying the breakdown of information processing are poorly known. Better understanding of the neural circuits involved in information processing may assist in early identification of predisposition to the disease. Using fMRI, we examined different levels of information comprehension elicited by naturally presented stimuli. Healthy participants, patients with first episode schizophrenia and their undiagnosed siblings listened to a real-life narrated story and scrambled versions of it. To estimate the level of synchronization in response time courses, we calculated inter-subject correlation (inter-SC) across the entire stimuli within each group. The time-scale gradients found in healthy and siblings groups were consistent with our previous findings. Within the schizophrenia group, the reliability patterns obtained for the shortest and intermediate temporal scales were similar to patterns observed in healthy groups. However, the analysis of responses to story condition (long temporal scale) revealed robust and widespread disruption of the inter-SC. In comparison to healthy groups, the response time courses to the story were highly variable within the schizophrenia group, although some significant inter-SCs in the TPJ and precuneus were found. The hierarchical temporal deficit is a fundamental trait that may be a better target for the study of the etiology and pathophysiology of the disease.
Disclosure of interestThe authors have not supplied their declaration of competing interest.