9 Most Embarrassing Questions Answered By Science

According to one study by the Society for Endocrinology, morning wood could well be the penile equivalent of your chap twiddling it's thumbs. Normally, throughout the day, your brain is always keeping the little guy in check, to ensure he doesn't go rogue. However, when you enter REM sleep at night, the noradrenergic cells responsible for inhibiting erections are switched off, leaving the penis to do its own thang.