The relationship between men's endogenous levels of testosterone and their penile responses to erotic stimuli.

The endogenous levels of testosterone of six nonclinical, sexually functional men were compared to the magnitude and speed of development of their objectively measured penile erections to repeated presentations of an erotic film und to their self-reported sexual activity. Plasma testosterone concentrations were significantly correlated with two measures of the magnitude of film-elicited sexual arousal (i.e., both peak and mean erection) and with one measure of the speed of development of sexual arousal (i.e., the latency to 90% of full erection) but not with the other (i.e., the latency to 20% of full erection). There was also a significant inverse relationship between testosterone levels and their reported frequency of orgasm by any means. but the reported time from their last orgasm was not related to testosterone levels.