Don't know if anyone saw this in the Guardian last week, but it's quite interesting:
"There's a young student at this university," neurologist Professor John Lorber of Sheffield University told Science magazine in December 1980, "who has an IQ of 126, has gained a first-class honours degree in mathematics, and is socially completely normal. And yet the boy has virtually no brain."
A scan revealed that the student had only 1mm of brain tissue lining the inside of his skull - fluid filled the area where the rest of his brain should have been. His was an extreme case of hydrocephalus, or "water on the brain", whereby cerebrospinal fluid fills the brain instead of circulating around it. Most sufferers can lead normal lives if regularly treated.
But if he had no brain, where was his mind?
Similar questions are raised by cases of "transplant memories". In 1988, Claire Sylvia received a heart and double-lung transplant. After the operation, she underwent some apparent personality changes: she began to have unusual (for her) cravings for beer, green peppers and chicken nuggets; she dreamed about beautiful women and experienced homosexual urges. She also dreamed of meetings with a young man called Tim.
Alarmed, Sylvia sought out her donor's family and discovered that her new organs had belonged to an 18-year-old boy, called Tim. Tim had a penchant for the same foods she was craving - he was eating chicken nuggets when he died - and Sylvia felt he was the boy in her dreams.
In the 19th century, German anatomist Leopold Auerbach observed a complex network of nerve cells in the human digestive tract. This nerve bundle, a "second brain" containing more nerve cells than the spinal cord, was recently rediscovered by Michael Gershon at Columbia University. Professor Wolfgang Prinz in Munich has also studied this, and thinks it could govern some of our emotional and physical responses to thoughts and events - hence, perhaps, "gut feelings".
Georgetown University's Dr Candace Pert has suggested that neuropeptides are linked to our sense of self. These chemicals, found in all our major organs and muscles, enable communication between the mind and body. Pert's theory is that they also carry our emotions and our memories. Is consciousness diffused throughout the body with them?