The following item is from the Macular Degeneration Foundation.
A 93 year-old woman with severe macular degeneration began to have hallucinations. After being examined at the New York Presbyterian Hospital/Cornell Medical Center in New York City. They found nothing wrong with her brain, but no explanation for the hallucinations. Her daughter researched the problem on the Internet and found that the syndrome is well known in England.
In 1769, Charles Bonnet described this condition. ‘Sufferers who are mentally healthy people with significant visual loss have vivid, complex, and recurrent visual hallucinations.’ The retina is badly damaged by macular degeneration and sends strange messages to the brain that gets confused and tries to interpret these jumbled messages which results in hallucinations. Quite simply, it is a damaged retina, not a damaged brain. This knowledge informs and consoles the individual who may experience hallucinations with macular degeneration.
All individuals with macular degeneration, retinal disease or severe visual loss and all doctors who serve them should be aware of the occurrence of hallucinations that might accompany their disease.