Compensatory hallucinogenesis across three neuropsychiatric disorders: a Bayesian account.
Brain communications January 1, 2026 Raina Vin, Jordan Galbraith, Rashina Seabury et al.
Hallucinations may arise from an over-reliance on prior knowledge during perception, potentially as a compensatory response to degraded sensory information. This perspective unifies visual hallucinations across Charles Bonnet syndrome, dementia with Lewy bodies, and psychosis within a Bayesian computational framework. In each disorder, sensory signal disruptions at different levels of the visual processing hierarchy produce hallucinations with distinct characteristics, reflecting the localization and overtness of the disruption. Discrete sensory disruptions in Charles Bonnet syndrome translate to hallucinations via known circuits, while different disruptions in dementia with Lewy bodies and schizophrenia lead to distinct phenomenology, comorbidities, and circuit involvement. This framework may help identify pathophysiologically distinct patient subgroups and guide new interventions.