Visual release hallucinations
|Visual release hallucinations|
|Other names||Charles Bonnet syndrome (CBS)|
Visual release hallucinations, also known as Charles Bonnet Syndrome or CBS, are a type of psychophysical visual disturbance and the experience of complex visual hallucinations in a person with partial or severe blindness.
First described by Charles Bonnet in 1760, the term Charles Bonnet Syndrome was first introduced into English-speaking psychiatry in 1982. A related type of hallucination that also occurs with lack of visual input is the closed-eye hallucination.
Signs and symptoms
People with significant vision loss may have vivid, complex recurrent visual hallucinations (fictive visual percepts). One characteristic of these hallucinations is that they usually are "lilliputian" (hallucinations in which the characters or objects are smaller than normal). The most common hallucination is of faces or cartoons. Sufferers understand that the hallucinations are not real, and the hallucinations are only visual, that is, they do not occur in any other senses, e.g. hearing, smell or taste. Among older adults (> 65 years) with significant vision loss, the prevalence of Charles Bonnet syndrome has been reported to be between 10% and 40%; a 2008 Australian study found the prevalence to be 17.5%. Two Asian studies, however, report a much lower prevalence. The high incidence of non-reporting of this disorder is the greatest hindrance to determining the exact prevalence; non-reporting is thought to be a result of sufferers being afraid to discuss the symptoms out of fear that they will be labelled insane.
People suffering from CBS may experience a wide variety of hallucinations. Images of complex colored patterns and images of people are most common, followed by animals, plants or trees and inanimate objects. The hallucinations also often fit into the person's surroundings.
CBS predominantly affects people with visual impairments due to old age, diabetes or other damage to the eyes or optic pathways. In particular, central vision loss due to a condition such as macular degeneration combined with peripheral vision loss from glaucoma may predispose to CBS, although most people with such deficits do not develop the syndrome.
The syndrome can also develop after bilateral optic nerve damage due to methyl alcohol poisoning.
Because there is no prescribed treatment, the first starting place is to reassure the CBS sufferer of their sanity, and some charities provide specialist hallucination counseling "buddies" (people who have had CBS, or have CBS and are no longer fazed by it) to talk to on the telephone.
The physician will consider on a case-by-case basis whether to treat any depression or other problems that may be related to CBS.
There is no treatment of proven effectiveness for CBS. Some people experience CBS for anywhere from a few days up to many years, and these hallucinations can last only a few seconds or continue for most of the day. For those experiencing CBS, knowing that they are suffering from this syndrome and not a mental illness seems to be the best treatment so far, as it improves their ability to cope with the hallucinations. Most people with CBS meet their hallucinations with indifference, but they can still be disturbing because they may interfere with daily life. Interrupting vision for a short time by closing the eyes or blinking is sometimes helpful.
The disease is named after the Swiss naturalist Charles Bonnet, who described the condition in 1760. He first documented it in his 89-year-old grandfather who was nearly blind from cataracts in both eyes but perceived men, women, birds, carriages, buildings, tapestries, physically impossible circumstances and scaffolding patterns.
Society and culture
The syndrome is discussed in
- Vilayanur S. Ramachandran's book Phantoms in the Brain. Ramachandran suggests that James Thurber, who was blinded in one eye as a child, may have derived his extraordinary imagination from the syndrome.
- Vikram Chandra's book Sacred Games (2006)
- David Eagleman's book Incognito: The Secret Lives of the Brain
- Oliver Sacks' 2012 book Hallucinations
- The Indian movie Jawan of Vellimala released in 2012, where Mammootty is a victim of this disease.
- "The Black Canvas" (2014), a chamber opera by the Greek composer Spyros Syrmos, is about a celebrated painter whose visions are caused by CBS.
- Margaret Atwood's short story "Torching the Dusties"
- Deborah Lawrenson's novel "The Lantern" (2011)
- Gareth Brookes' graphic novel A Thousand Coloured Castles (2017)
- The 2019 Netflix film Velvet Buzzsaw
- Dealt, 2017 documentary about notable victim Richard Turner
- Phantom eye syndrome
- Musical ear syndrome – Auditory hallucination associated with hearing loss
- Ganzfeld effect – psychological phenomenon
- Hypnagogia – State of consciousness in transition from wakefulness to sleep
- Anton–Babinski syndrome
- de Morsier, G (1967). "Le syndrome de Charles Bonnet: hallucinations visuelles des vieillards sans deficience mentale" [Charles Bonnet syndrome: visual hallucinations of the elderly without mental impairment]. Ann Med Psychol (in French). 125: 677–701.
- Vukicevic, Meri; Fitzmaurice, Kerry (2008). "Butterflies and black lacy patterns: The prevalence and characteristics of Charles Bonnet hallucinations in an Australian population". Clinical & Experimental Ophthalmology. 36 (7): 659–65. doi:10.1111/j.1442-9071.2008.01814.x. PMID 18983551.
- Berrios, German E.; Brook, Peter (1982). "The Charles Bonnet Syndrome and the Problem of Visual Perceptual Disorders in the Elderly". Age and Ageing. 11 (1): 17–23. doi:10.1093/ageing/11.1.17. PMID 7041567.
- TED2009. "Oliver Sacks: What hallucination reveals about our minds | Video on". Ted.com. Archived from the original on 2013-07-08. Retrieved 2013-07-03.
- Schultz, G; Melzack, R (1991). "The Charles Bonnet syndrome: 'phantom visual images'". Perception. 20 (6): 809–25. doi:10.1068/p200809. PMID 1816537.
- Mogk, Lylas G.; Riddering, Anne; Dahl, David; Bruce, Cathy; Brafford, Shannon (2000). "Charles Bonnet Syndrome In Adults with Visual Impairments from Age-Related Macular Degeneration". In Arditi, Aries; Horowitz, Amy; Lang, Mary Ann; Rosenthal, Bruce; Seidman, Karen; Stuen, Cynthia (eds.). Vision Rehabilitation. pp. 117–9. ISBN 978-90-265-1631-3.
- Tan, C S H; Lim, V. S.; Ho, D. Y.; Yeo, E; Ng, B. Y.; Au Eong, K. G. (2004). "Charles Bonnet syndrome in Asian patients in a tertiary ophthalmic centre". British Journal of Ophthalmology. 88 (10): 1325–9. doi:10.1136/bjo.2004.041947. PMC 1772345. PMID 15377560.
- Abbott, Emily J.; Connor, Gillian B.; Artes, Paul H.; Abadi, Richard V. (2007). "Visual Loss and Visual Hallucinations in Patients with Age-Related Macular Degeneration (Charles Bonnet Syndrome)". Investigative Ophthalmology & Visual Science. 48 (3): 1416–23. doi:10.1167/iovs.06-0942. PMID 17325191.
- Olbrich, H. M.; Lodemann, E; Engelmeier, M. P. (1987). "Optical hallucinations in the aged with diseases of the eye". Zeitschrift für Gerontologie. 20 (4): 227–9. PMID 3660920.
- Bonnet Charles (1760) Essai Analytique sur les facultés de l’âme. Copenhagen: Philibert, pp 426–428
- "Bonnet's syndrome (Charles Bonnet)". Whonamedit. Archived from the original on 2014-02-23. Retrieved 2013-07-03.
- V.S. Ramachandran; Sandra Blakeslee (1988). Phantoms in the Brain. HarperCollins. pp. 85–7.
- "Movie Review: Jawan of Vellimala". NowRunning. Archived from the original on 1 January 2013. Retrieved 14 January 2013.
- Information on Charles Bonnet syndrome from RNIB
- National Public Radio article with an audio segment about Charles Bonnet syndrome
- Oliver Sacks: What hallucination reveals about our minds Ted Talk, Feb 2009.
- Fortean Times article on Charles Bonnet syndrome
- 'Damn Interesting' article on Charles Bonnet syndrome
- W Burke (2002). "The neural basis of Charles Bonnet hallucinations: a hypothesis". Journal of Neurology, Neurosurgery & Psychiatry. 73 (5): 535–541. doi:10.1136/jnnp.73.5.535. PMC 1738134. PMID 12397147.