Sleep-related erections: absence of change following presleep sexual arousal.

We examined the effects of a brief period of sexual arousal before sleep on sleep-related erections (SREs) to add to our knowledge concerning those factors that affect SREs. Twelve subjects watched a 5 minute sexually explicit video before sleep. On other evenings they watched a dysphoric arousal video or a lecture (neutral) video. Sleep and SREs were recorded throughout the following night. Although the brief sexual arousal video produced a full or near full erection in all subjects, no significant effect on subsequent SREs occurred. We conclude that the control of SREs in young healthy subjects is insulated against the effect of a brief period of sexual arousal before sleep.