How Does an Erection Occur? Understanding the physiological process of getting an erection can help you look at ED in a whole new light. Erectile dysfunction means something is standing in the way of your body’s natural process of getting and sustaining an erection.
It doesn't matter if you're having a hot sex dream or a zombie apocalypse nightmare -- your penis gets hard during that period of the sleep cycle.
WebMD explains the parts of a penis, how you get an erection, and how ejaculation happens.
An erection is a physiological phenomenon in which the penis becomes firm, engorged, and The penis may erect during sleep or be erect on waking up.
Find out facts about your penis, including erections, penis length and how the penis can break if violently twisted when erect.