What would we think about a person who, while knowing that they are alive, thinks that their flesh is rotting, that they have no blood, that they lack internal organs? What about someone whose left hand is twitching towards their neck and tries to strangle them, while their right hand is desperately trying to stop it? What about a person who puts on shoes before putting on their socks or who puts butter on the bread before putting the bread in the toaster?

This book provides a systematic analysis of these and many other strange behaviors that can be caused by injuries or other malfunctions in specific areas of the brain.