He also solicited prostitution at a massage parlor, something he said he had never previously done.

He poured his time into child-pornography Web sites and magazines. He developed an interest in child pornography-and not just a little interest, but an overwhelming one. Take the 2000 case of a 40-year-old man we’ll call Alex, whose sexual preferences suddenly began to transform. As we develop better technologies for probing the brain, we detect more problems, and link them more easily to aberrant behavior. Stories like Whitman’s are not uncommon: legal cases involving brain damage crop up increasingly often. Whitman’s intuition about himself-that something in his brain was changing his behavior-was spot-on. In humans, activity in the amygdala increases when people are shown threatening faces, are put into frightening situations, or experience social phobias. Female monkeys with amygdala damage often neglected or physically abused their infants. In the 1930s, the researchers Heinrich Klüver and Paul Bucy demonstrated that damage to the amygdala in monkeys led to a constellation of symptoms, including lack of fear, blunting of emotion, and overreaction. By the late 1800s, researchers had discovered that damage to the amygdala caused emotional and social disturbances. The amygdala is involved in emotional regulation, especially of fear and aggression. This tumor, called a glioblastoma, had blossomed from beneath a structure called the thalamus, impinged on the hypothalamus, and compressed a third region called the amygdala. He discovered that Whitman’s brain harbored a tumor the diameter of a nickel. Whitman’s body was taken to the morgue, his skull was put under the bone saw, and the medical examiner lifted the brain from its vault. After one session I never saw the Doctor again, and since then I have been fighting my mental turmoil alone, and seemingly to no avail. I talked with a Doctor once for about two hours and tried to convey to him my fears that I felt overwhelming violent impulses.

Charles whitman