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Visual hallucinations in blindness: the Charles Bonnet syndrome
The International Journal of Neuroscience
|July 1, 1982
Summary
Complex visual hallucinations in a blind patient resolved after brain tumor removal. This suggests release hallucinations in blindness stem from sensory loss and central nervous system (CNS) dysfunction.
Area of Science:
- Neuroscience
- Ophthalmology
- Neurology
Background:
- Complex visual hallucinations, known as Charles Bonnet syndrome, can occur in individuals with vision loss.
- The underlying mechanisms linking sensory deprivation to these hallucinations are not fully understood.
Observation:
- A 64-year-old woman, blind for 14 years, experienced vivid hallucinations of snakes.
- These complex visual hallucinations involved snakes appearing on people and her own body.
Findings:
- Surgical removal of a large suprasellar meningioma led to the complete resolution of her hallucinations.
- This case highlights a potential link between a central nervous system (CNS) lesion and the manifestation of release hallucinations.
Implications:
- The findings suggest that release hallucinations in the blind may result from a combination of sensory deprivation and impaired CNS function.
- This case underscores the importance of considering both sensory and neurological factors in the etiology of complex visual hallucinations in visually impaired individuals.
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