55. Abnormal Claustral–Cortical Functional Brain Networks in People With Schizophrenia During Perception and Resting: Brain Network Dynamics Underlying Psychotic Symptoms

摘要

>Background: Positive symptoms including hallucinations and delusions are hallmark symptoms of schizophrenia, but their precise neural mechanisms have not yet been clarified. Recent clinical findings suggested that positive symptoms might be related to abnormalities in the claustrum. The claustrum, a thin grey matter deep brain structure, has uniquely high structural connectivity with almost all cortical and limbic brain regions and contains both cell types found in cortical and subcortical brain. The claustrum has been hypothesized to be a neural locus of consciousness that enhances perceptual salience through its neural oscillatory synchronization with cortical regions. Deficient claustral–cortical neural synchrony might underlie abnormal cortical functional coordination associated with perceptual deficits and hallucinations in schizophrenia. A recent functional MRI study found that adolescents with psychotic symptoms had reduced claustral–cortical intrinsic functional connectivity during resting state. Therefore, abnormal claustral connectivity with key nodes of sensory cortical and intrinsic networks might play an important role in the development of psychotic symptoms. >Methods: Sixteen patients with schizophrenia (SZ) and 16 healthy controls participated in this study. Magnetoencephalography (MEG) was collected using a 248-sensor axial gradiometer MEG system while participants performed a visual perception task as well as during resting. The claustrum volumes were manually segmented using individual T1-weighted MRI. Boundary element method (BEM) individual head models of cerebral cortex and the claustrum, L-2 norm minimum norm algorithm, and principal component analysis were used to compute cortical/claustral source time series. Interregional functional connectivity between the cortical/claustral regions of interests (ROIs) was estimated by computing time-frequency phase locking value (PLV) between oscillatory neural activities of the ROIs. >Results: The claustral–visual cortical PLV during visual perception task was reduced in SZ, especially in the late induced gamma oscillations. This deficit was even more serious in SZ with prominent visual hallucinations than in SZ with auditory hallucinations. The claustral–cortical PLV in evoked and induced neural oscillations was predictive of task performances as well as schizophrenic symptom severity. Graph theoretical analysis of whole-brain interregional PLV during resting state will be carried out to further elucidate the role of the claustral–cortical networks in abnormal intrinsic brain network dynamics in SZ. >Conclusion: Findings suggest that deficient claustral–cortical neural synchrony might lead to visual perceptual deficits and schizophrenic symptoms including hallucinations. The role of claustral–cortical connectivity in spontaneous brain network dynamics and formation of delusions will be also discussed.