Temporal relationship between nocturnal erections and rapid eye movement episodes in healthy men

The exact temporal relationship between spontaneous nocturnal erections and rapid eye movement (REM) sleep was studied in healthy men with the aim of creating a basis for a more sophisticated analysis of nocturnal erection measurements in physiological research and clinical applications. The vast majority of erectile events was coupled to REM episodes, where the latency between the beginning of erections and REM episodes showed a large variability. Moreover, a correlation analysis revealed a highly significant decrease of the latency over the course of the night. The time variant properties of the coupling between erections and REM sleep point to more complex dynamics of the central control of erections with regard to sleep regulation, indicating that REM sleep and REM-related erections are not completely interdependent. Beside the possibility of obtaining further insight into the physiological mechanisms underlying erectile function, the consideration of dynamic aspects in the assessment of nocturnal erection measurements might have potential clinical implications regarding both the diagnosis and the evaluation of therapies for erectile dysfunction.