A TEDtalk with Oliver Sacks!
Oliver Sacks, the famous British neurologist, recently gave a talk at TED concerning the topic of hallucinations.
Dr. Sacks is probably best known for his popular books in which he describes case studies of his patients with intriguing neurological disorders. One of my favorites is: The Man Who Mistook His Wife For A Hat: And Other Clinical Tales. And then you probably know: Awakenings, which was made into a movie starring Robert De Niro and Robin Williams. I believe his most recent book is: Musicophilia: Tales of Music and the Brain, Revised and Expanded Edition, in which Dr. Sacks examines the effects of music on the brain.
Well, this TED talk is about hallucinations. Well, not just hallucinations, but a particular type of disorder that causes hallucinations called, Charles Bonnett Syndrome. This is a disorder in which people who are blind experience visual hallucinations, and people who are death experience auditory hallucinations. It's very interesting. Apparently the syndrome is common, occurring in about 10% of the blind population, though it is probably under-reported.
These people are not crazy. They are perfectly sane, healthy individuals. The syndrome seems to occur in people who are blind from macular degeneration. What seems to be happening is that, as the structures that gather sensory information gradually break down, the visual/auditory parts of the brain go in hyper-drive. They are over-working, and the brain is trying to make sense of the jumbled mess of activation. Well, Dr. Sacks describes it a lot better, and includes some funny stories (including one about a woman who hallucinates Kermit the Frog). I'm posting the talk below, so check it out: