Neuropsychiatry of complex visual hallucinations
Article first published online: 2 AUG 2006
Australian and New Zealand Journal of Psychiatry
Volume 40, Issue 9, pages 742–751, September 2006
How to Cite
Mocellin, R., Walterfang, M. and Velakoulis, D. (2006), Neuropsychiatry of complex visual hallucinations. Australian and New Zealand Journal of Psychiatry, 40: 742–751. doi: 10.1111/j.1440-1614.2006.01878.x
- Issue published online: 2 AUG 2006
- Article first published online: 2 AUG 2006
- Received 19 February 2006; accepted 23 February 2006.
- Charles Bonnet;
- visual hallucination
Objective: To describe the phenomenology and pathophysiology of complex visual hallucinations (CVH) in various organic states, in particular Charles Bonnet syndrome and peduncular hallucinosis.
Method: Three cases of CVH in the setting of pontine infarction, thalamic infarction and temporoparietal epileptiform activity are presented and the available psychiatric, neurological and biological literature on the structures of the central nervous system involved in producing hallucinatory states is reviewed.
Results: Complex visual hallucinations can arise from a variety of processes involving the retinogeniculocalcarine tract, or ascending brainstem modulatory structures. The cortical activity responsible for hallucinations results from altered or reduced input into these regions, or a loss of ascending inhibition of their afferent pathways.
Conclusions: A significant degree of overlaps exists between the concepts of Charles Bonnet syndrome and peduncular hallucinosis. The fluidity of these eponymous syndromes reduces their validity and meaning, and may result in an inappropriate attribution of the underlying pathology. An understanding of how differing pathologies may produce CVH allows for the appropriate tailoring of treatment, depending on the site and nature of the lesion and content of perceptual disturbance.