Neural pathways controlling ejaculation. Sympathetic (Σ), parasympathetic (PΣ), and somatic nerves originating in lumbosacral spinal nuclei command the peripheral anatomical structures responsible for ejaculation. Sensory afferents originating in genital areas are integrated at the spinal and brain levels. Activity of spinal preganglionic and motor neurones is under the influence of peripheral and supraspinal inputs. Abbreviations: BN, bladder neck; BS, bulbospongiosus muscle; Ep, epididymis; P, prostate; SV, seminal vesicle; VD, vas deferens.