REM sleep and EEG abnormalities in criminal psychopaths.

Hare's (1970) REM deficit theory in psychopathy was investigated. The repeated finding of EEG slowing in waking psychopaths has been interpreted as reflecting cortical immaturity, cortical underarousal, and an intense need for sensory stimulation of psychopaths. REM sleep has been implicated in cortical maturation during development and in daily cortical maintenance. Hare postulated a possible REM deficit in psychopaths to account for their apparent cortical abnormalities. Three groups of incarcerated criminals were investigated: psychopaths with normal waking EEGs (n = 8), psychopaths with abnormal EEGs (n = 9), and nonpsychopaths with normal EEGs (n = 6). The sleep stages of each inmate were recorded for one baseline and two experimental nights. No significant differences were found in the sleep patterns of these groups using stepwise, multiple discriminant analysis. The psychopaths with abnormal EEGs tended to have the highest REM time and REM% of the inmates, contrary to Hare's theory.