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Related Experiment Video

Updated: Nov 5, 2025

Assessing Binocular Central Visual Field and Binocular Eye Movements in a Dichoptic Viewing Condition
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Visual hallucinations.

Rimona S Weil1, A J Lees2

  • 1Dementia Research Centre, University College London, London, UK r.weil@ucl.ac.uk.

Practical Neurology
|May 14, 2021
PubMed
Summary
This summary is machine-generated.

Visual hallucinations are common in Parkinson's disease and dementia with Lewy bodies. This review explores their mechanisms and proposes a framework for understanding their prevalence in these conditions.

Keywords:
Parkinson diseasedementiahallucinationsvision

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Area of Science:

  • Neurology
  • Neuroscience
  • Ophthalmology

Background:

  • Visual hallucinations are complex neurological phenomena with diverse causes.
  • Commonly linked to neurodegenerative diseases like Parkinson's disease (PD) and dementia with Lewy bodies (DLB).
  • Also associated with visual impairment (Charles Bonnet syndrome) and focal brain lesions (peduncular hallucinosis).

Purpose of the Study:

  • To review the underlying mechanisms of visual hallucinations across various conditions.
  • To propose a framework explaining the high incidence in PD and DLB.
  • To discuss current treatment strategies for visual hallucinations in these patient groups.

Main Methods:

  • Literature review of studies on visual hallucinations.
  • Analysis of proposed etiological mechanisms, including visual processing, network dysfunction, and neurotransmitter changes.
  • Synthesis of findings to develop a unifying explanatory framework.

Main Results:

  • Visual hallucinations stem from visual loss, altered brain network activity, and neurotransmitter imbalances.
  • A framework is proposed to elucidate why PD and DLB are particularly associated with these hallucinations.
  • Treatment approaches for visual hallucinations in PD and DLB are reviewed.

Conclusions:

  • Understanding the mechanisms of visual hallucinations is crucial for diagnosis and management.
  • The proposed framework offers insights into the predilection for visual hallucinations in PD and DLB.
  • Further research into targeted treatments can improve patient outcomes.