Psychogenic Erection
From Encyclopedia of Sex and Sexuality
During most of his life a man’s penis is limp. For most men this limpness is interrupted periodically with periods of stiffness and hardness—“erectness.” Through childhood, youth, and vigorous manhood, a signal from the brain can cause the penis to become erect: a sexy thought can trigger an erection. A boy in bed thinks of women taking off their clothing: his penis hardens. A man riding home on the commuter train thinks of his lover (or perhaps of an attractive coworker): he has an erection. A man in bed with his wife has a problem raising an erection: he thinks of someone more exciting to produce an erection. This successful signalling from the brain to the penis is called a psychogenic erection. In later life the penis may need more direct stimulation; stroking by the partner can be effective. The thought-induced, mental image-induced, or situationally-induced erection may not be attainable in later years, but many middle-aged or older couples are still sexually active and gratified without it.
