Dreaming and hallucinations - Continuity or discontinuity? Perspectives from dementia with Lewy bodies

► There is complex relationship between visual dreams and hallucinations despite overlapping phenomenology and brain systems. ► Differences in visual phenomenology may reflect the absence of vision during sleep. ► Neurochemical changes in sleeping and dreaming tend in opposite directions. ► There may be more similarity in brain function and phenomenology in dream logic and delusional thinking.