Psychosurgery may be used to deliberately destroy certain areas of the human brain to produce more amenable individuals. The technique is occasionally used to treat violent or criminal behaviour. Post-operative blunting of the personality, apathy and irresponsibility are frequent, and some researchers mention deterioration of the intellect in those of high intelligence. Psychosurgery is subject to strong criticism because of the impossibility of obtaining the informed consent of the psychotic or mentally handicapped patient to such treatment; because of its evolving nature; and because of the lack of a clear indication that alternative treatments have been exhausted.