White matter connectivity disruptions in the pre-clinical continuum of psychosis: A connectome study

Abstract

BackgroundWidespread white matter disruptions in schizophrenia have been commonly reported, but it remains unanswered whether these abnormalities are associated with schizophrenia specifically or whether they range along a psychotic continuum into the healthy population. Investigating the extent of white matter connectivity disruptions specific to psychotic-like experiences in healthy individuals is insofar important as it is a necessary first step towards the development of prodromal psychosis biomarkers.\n\nMethodsHigh resolution, multi-shell diffusion-weighted magnetic resonance images were acquired from 89 healthy individuals. Whole-brain white matter fiber tracking was performed to quantify the strength of white matter connections. Network-based statistics were applied to white matter connections in a regression model in order to test for a linear relationship between streamline count and psychotic-like experiences.\n\nResultsA significant subnetwork was identified whereby streamline count declined with increasing quantity of psychotic-like experiences. This network of significant connectivity reductions affected all cortical lobes, subcortical structures and the cerebellum.\n\nConclusionA widespread network of linearly declining connectivity strength with increasing number of psychotic-like experiences was identified in healthy individuals. This finding is in line with white matter connectivity reductions reported from early to chronic stages of schizophrenia. We suggest that these white matter changes might be a potential biomarker for the identification of individuals at high risk for transitioning to psychosis.