Dominant Nervous System During Erection and Ejaculation: Parasympathetic; Sympathetic

  Dominant Nervous System During Erection and Ejaculation: Parasympathetic; Sympathetic The process of achieving an erection and experiencing ejaculation in sexually aroused males involves the interplay of the parasympathetic and sympathetic divisions of the autonomic nervous system. While the parasympathetic system dominates during erection, the sympathetic system takes over during ejaculation, orchestrating the complex physiological responses associated with these sexual functions. Explanation and Reference: 1. Erection Phase - Parasympathetic Dominance: The parasympathetic nervous system is primarily responsible for vasodilation, which is crucial for the engorgement of blood vessels in the penis leading to an erection. During sexual arousal, parasympathetic nerve fibers release nitric oxide, a vasodilator that relaxes smooth muscle cells in penile blood vessels, allowing increased blood flow and the subsequent erection (Andersson & Wagner, 1995). 2. Ejaculation Phase - Sympathetic Dominance: In contrast, ejaculation is primarily controlled by the sympathetic nervous system. The sympathetic nerves are responsible for coordinating the contraction of smooth muscles in the reproductive tract, including the vas deferens, seminal vesicles, and muscles at the base of the penis, to facilitate the expulsion of semen during ejaculation (Andersson & Wagner, 1995). 3. Role Reversal: The shift from parasympathetic dominance during erection to sympathetic dominance during ejaculation exemplifies the intricate coordination between these two branches of the autonomic nervous system in regulating sexual responses in males. In summary, the parasympathetic nervous system plays a key role in achieving an erection, while the sympathetic nervous system takes over to facilitate ejaculation, highlighting the dynamic interplay between these systems during different phases of male sexual function. Reference: Andersson, K. E., & Wagner, G. (1995). Physiology of penile erection. Physiological Reviews, 75(1), 191-236.

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