Brain Structural and Functional Alteration Network Localization of Visual Hallucinations.

Background and hypothesis: Visual hallucinations (VH), a key symptom in neurodegenerative and psychiatric disorders, are associated with a more severe psychopathological profile and less favorable outcome. Neuroimaging research has revealed widespread brain regions involved in VH, echoing the updated notion that neuropsychiatric symptoms correspond more closely to interconnected brain networks than to single brain regions. However, there is still a dearth of studies examining brain network localization of VH.

Study design: We initially identified brain structural and functional alterations specific to VH from 21 published neuroimaging studies with 418 VH and 522 non-VH individuals. By applying novel functional connectivity network mapping to large-scale discovery (n = 1113) and validation (n = 1093) resting-state functional magnetic resonance imaging datasets, we mapped these affected brain locations to 2 specific networks.

Study results: The VH structural alteration network comprised a broadly distributed set of brain regions principally implicating the frontoparietal and dorsal attention networks. The VH functional alteration network also consisted of widely distributed brain areas predominantly involving the ventral attention and frontoparietal networks.

Conclusions: Our findings may not only draw a more refined picture of the neurobiology of VH from a network perspective, but also potentially contribute to more targeted and effective treatment for VH.