Why does every NBME have one or two erection related questions??
From a girls perspective, is really hard to understand this penis/erection physiology questions
Robin Williams once said "God gave men two heads and only enough blood to work one at a time". Might help yall conceptualize that the penis has a "brain" of its own. The erotic dreams, reading and viewing erotic material all require input from the brain to reach the penis whereas penile stimulation is a local reflex.
Apparently theres role of sympathetic system in psychogenic erection and its comes from T11-L2. So if patient have transaction at L5 they lose reflex erection but still retain psychogenic one.
ABove T9 transaction cause loss of psychogenic erection
Worth noting that not only is there a separate reflex arc for non-psychogenic ejaculation, but that glandular secretion, emission (contraction of everything besides the penis muscles), and ejaculation (contraction of penis muscles i.e. ischiocavernosus and bulbospongiosus) are all under reflex control.
-- All efferents are parasympathetic EXCEPT for emission (sympathetic) and ejaculation (somatic). -- all afferents are pudendal n. except for psychogenic erection which starts with higher centers
Reflex erection--> somatic tactile stimuli to penis Can still happen if a spinal-cord transection occurs cranial to T10/T12.
verses
Sympathetic--> psychogenetic erection Males with cord transections above T9 are unable to achieve psychogenic erections.
submitted by โsattanki(82)
Apparently there is a completely separate spinal cord reflex where direct penile stimulation leads to an erection. This reflex only needs an intact arc in S2-S4, so as long as this region is not injured, an erection can still occur. However, with transection at C8, then the psychogenic erection reflex cannot occur, as this requires descending fibers from the cortex.