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Published on: November 21, 2013
[Hallucinations and dementia. Prevalence, clinical presentation and pathophysiology]
1Service de neurologie, Hôpital Henri Mondor, Créteil, France. gilles.fenelon@hmn.ap-hop-paris.fr
Revue Neurologique
|May 1, 2004
Summary
Hallucinations are common in dementia, particularly Lewy body dementia. Complex visual hallucinations are most frequent, often occurring at night and linked to cognitive decline.
Area of Science:
- Neuroscience
- Neurology
- Psychiatry
Context:
- Hallucinations are prevalent in neurodegenerative diseases like Alzheimer's, Parkinson's, and Lewy body dementia.
- Epidemiological data collection is challenging due to methodological issues.
- Prevalence is highest in Lewy body disease and parkinsonian dementia.
Purpose:
- To review the epidemiology, clinical features, and potential pathogenic mechanisms of hallucinations in degenerative diseases.
- To explore the relationship between cognitive impairment and hallucinations.
Summary:
- Complex visual hallucinations are predominant, often recurring nocturnally.
- Associated psychological and behavioral disorders, such as delusions, can occur.
- Potential mechanisms involve neurotransmitter imbalances (cholinergic-monoaminergic) and aberrant cortical activation.
Impact:
- Highlights the need to differentiate causes of hallucinations in elderly patients.
- Suggests a complex interplay between cognitive decline and hallucinatory experiences.
- Underscores the limited understanding of underlying pathogenic mechanisms and the need for further research.
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