In 1863 Eckhard first demonstrated that stimulation of the sacral nerves produced penile erection; he called the nerves the nervi erigentes.

Semans and Langsworthy (1938) demonstrated in the cat that stimulation of the sacral and hypogastric nerves would result in a sexual response in the male organ. Dilation of the penile arteries and erection of the penis was produced by stimulation of the first, second, and third sacral nerves.

Stimulation of other appropriate regions ultimately resulted in ejaculation of semen. Finally, stimulation of the sympathetic nerves produced constriction of the penile arteries with subsidence of the erection. In 1957 Hotchkiss summarised the peripheral mechanisms in the male.