The Insanity Defense
For a person to be legally insane their brain would have to be in a state of trauma. Trauma can be physical or purely mental. The reason trauma causes insanity is because it alters the function of the brain. For example, people with schizophrenia have a gene that actually causes the disease, when people see visions that aren’t really there it could cause them to do things they otherwise wouldn’t do. In determining someone's insanity, neuroscientific evidence has been shown to be much more useful than a psycho evaluated testimony in influencing a jury if guilty. This is because showing people that there is actually something wrong with the brain with data and images is much better than just having them take your word for it.