PT - JOURNAL ARTICLE AU - Rimona S Weil AU - A J Lees TI - Visual hallucinations AID - 10.1136/practneurol-2021-003016 DP - 2021 Aug 01 TA - Practical Neurology PG - 327--332 VI - 21 IP - 4 4099 - http://pn.bmj.com/content/21/4/327.short 4100 - http://pn.bmj.com/content/21/4/327.full SO - Pract Neurol2021 Aug 01; 21 AB - Visual hallucinations have intrigued neurologists and physicians for generations due to patients’ vivid and fascinating descriptions. They are most commonly associated with Parkinson’s disease and dementia with Lewy bodies, but also occur in people with visual loss, where they are known as Charles Bonnet syndrome. More rarely, they can develop in other neurological conditions, such as thalamic or midbrain lesions, when they are known as peduncular hallucinosis. This review considers the mechanisms underlying visual hallucinations across diagnoses, including visual loss, network dysfunction across the brain and changes in neurotransmitters. We propose a framework to explain why visual hallucinations occur most commonly in Parkinson’s disease and dementia with Lewy bodies, and discuss treatment approaches to visual hallucinations in these conditions.