Which statement best describes reflexive erection after SCI when sacral reflexes are intact but there is no supraspinal input?

Which statement best describes reflexive erection after SCI when sacral reflexes are intact but there is no supraspinal input?

• A. Psychogenic erection only
• B. Both psychogenic and reflexive erection
• C. Reflexive erection only
• D. Neither psychogenic nor reflexive erection

Answer: (D)

Erection depends on two separate neural pathways: a psychogenic pathway that starts in the brain and a reflexive pathway that originates in the sacral spinal cord (S2–S4). When spinal cord injury cuts off supraspinal input but leaves the sacral reflex arc intact, the brain can no longer initiate erection (psychogenic), but the sacral reflex arc can still trigger an erection in response to genital stimulation. So, with intact sacral reflexes but no brain input, you would expect reflexive erection to be possible while psychogenic erection is not. The scenario describes reflexive erection only.

Erection depends on two separate neural pathways: a psychogenic pathway that starts in the brain and a reflexive pathway that originates in the sacral spinal cord (S2–S4). When spinal cord injury cuts off supraspinal input but leaves the sacral reflex arc intact, the brain can no longer initiate erection (psychogenic), but the sacral reflex arc can still trigger an erection in response to genital stimulation.

So, with intact sacral reflexes but no brain input, you would expect reflexive erection to be possible while psychogenic erection is not. The scenario describes reflexive erection only.