SEVERAL STUDIES HAVE ATTEMPTED TO ACCOUNT FOR THE PSYCHOPATH'S CHARACTERISTIC INABILITY TO DELAY GRATIFICATION OF NEEDS AND ITS EFFECT ON BEHAVIOR. RESEARCH INDICATES THAT PSYCHOPATHY MAY BE ASSOCIATED WITH AUTONOMIC AND CORTICAL HYPERAROUSAL AND THAT CONDITIONS WHICH PERMIT OPTIMAL STIMULATION TO NORMAL PEOPLE TEND TO PRODUCE UNDERAROUSAL IN A PSYCHOPATH. CONSEQUENTLY, HE OR SHE TENDS TO BE BORED AND TO SEEK STIMULATION. A STUDY OF 66 FEMALE CRIMINALS WITH SOCIOPATHY AND HYSTERIA FOUND THAT SUCH SUBJECTS HAVE SIMILAR BACKGROUNDS OF PARENTAL DEPRIVATION AND SEVERE DISTURBANCE. THESE CHARACTERISTICS ARE SIMILAR TO THE LOW SOCIOECONOMIC CONDITIONS AND EMOTIONAL INSTABILITY IN THE BACKGROUND OF 40 ADOLESCENT FEMALE SHOPLIFTERS. ALTHOUGH MOST OF THE LATTER GROUP WERE SANE, NEUROLOGIC EXAMINATION INDICATED THAT A THIRD OF THE GIRLS HAD ELECTROENCEPHALOGRAM (EEG) ANOMALIES. THE FINDINGS OF A COMPARATIVE EEG STUDY OF 104 CRIMINALS AND A CONTROL SAMPLE CONFIRM PREVIOUS EVIDENCE OF ABNORMAL SLEEP PATTERNS IN CRIMINAL SUBJECTS. MOST OF THOSE WITH ABNORMAL EEG TRACES WHO ARE NOT PSYCHOTIC DO HAVE NONCLASSICAL FORMS OF EPILEPSY. A STUDY OF 194 CRIMINALS WITH FAST EEG ACTIVITY INDICATES DISORDER IN THE BRAIN WHICH OCCASIONALLY CAUSES CRIMINAL BEHAVIOR. ADDITIONAL RESEARCH INCLUDES EEG SURVEYS OF CRIMINAL PSYCHOPATHS WHICH FOUND THAT ALL PATIENTS WHOSE MAJOR OFFENSE WAS ASSAULT WERE PSYCHOMOTOR EPILEPTICS. REFERENCES ARE PROVIDED. (TWK)