@Vasska,
Asylums are ok... although... theres a shortage of chairs. LOL!
Also, there was an interesting joke a heard? and I am racking my brains trying to figure out where I heard it, but here it is.
"A doctor takes his first rounds at an asylum. He goes up to the first patient he sees and asks, "Who do you think you are?" The patient replied, "I, sir, am Napoleon!" "And how do you know you are Napoleon," asked the doctor. The patient replied, "Because God told me so." Then, from across the room, another patient yelled, "I... DID... NOT!!!"
But you cannot completely discount the physical factor (you don't discount it, but this is just in general). There are some diseases which effect memory and motor function.
The brain is a hard drive, but not the software. But occasionally, hard drives crash and the software differs. Curse you MS Vista!!!