Placing erection in context: the reflexogenic-psychogenic dichotomy reconsidered

Area of Science:

• Urology
• Neuroscience
• Sexual Medicine

Background:

• Penile erections are conventionally categorized as reflexogenic or psychogenic.
• This dichotomy has led to distinctions in neural mediation (spinal vs. supraspinal, pelvic vs. hypogastric) and stimulation types (perineal somesthetic vs. cranial nerve).
• Existing research presents conflicting evidence regarding the distinct roles of neural pathways and hormonal influences in different erectile contexts.

Purpose of the Study:

• To review evidence for differential regulation of penile erections in various contexts.
• To critically evaluate the established reflexogenic-psychogenic dichotomy.
• To propose alternative frameworks for understanding erectile function based on stimulus type and reflexivity.

Main Methods:

• Review of existing scientific literature on penile erection.
• Analysis of studies investigating neural mediation, hormonal sensitivity, and neurotransmitter roles (e.g., dopamine) in different erectile contexts.
• Examination of evidence from animal models and human studies, including those with spinal cord injuries.

Main Results:

• Evidence for distinct physiological roles of hypogastric nerves in psychogenic erection is suggestive but not conclusive.
• Androgen sensitivity appears context-dependent, with some erection types (e.g., nocturnal penile tumescence) showing higher sensitivity than others (e.g., visual erotic stimuli).
• Conflicting findings on dopamine's role in erection may be attributed to variations in experimental contexts.

Conclusions:

• The conventional reflexogenic-psychogenic dichotomy for penile erections is likely an oversimplification and may need revision.
• Alternative taxonomies are proposed, including distinguishing between weak (extrinsic non-somesthetic) and strong (memory/fantasy) psychogenic erections, and classifying stimuli as contact or noncontact on a reflexivity continuum.
• Future research should prioritize context and species-specific differences in erectile function to refine our understanding.