Refractory period (sex) autonomic feedback mechanism, rather than through central chemicals like oxytocin, serotonin, and prolactin. Autonomic feedback is already known to regulate other physiologic systems, such as breathing, blood pressure, and gut motility. This theory suggests that after male ejaculation, decreased wall tension in structures such as the seminal vesicles leads to a change in the fine autonomic signals sent from these organs, effectively creating a negative feedback loop. Such a mechanism is similar to decreased gastric and bowel motility once gastric contents have passed through. Once the feedback loop has been created, the refractory period remains until the loop is broken
Milk substitute Milk substitute A milk substitute (or, more precisely, an analogue of mammalian milk) (also called milk alternative or milk analogue) can refer to a liquid considered (particularly in the USA and other western countries) as a replacement for the milk from a mammal (mainly cows and humans). Mammalian milk analogues are white or whitish liquids that resemble either dairy or human breast milk. Milk substitutes for non-infant consumption take two very different forms: plant milks, which are liquids made from plants and may be home-made or commercially produced, and coffee creamers, synthetic products invented in the USA in the 1900s