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
Psychological refractory period caffeine intake have also been investigated. PRP is a product of the psychological refractory period paradigm, a paradigm in which two different stimuli are presented in rapid succession, each requiring a fast response. Stimulus onset asynchrony, the time that lapses between the presentations of the two stimuli, acts as the "independent variable" in this paradigm, and the reaction time to the second stimulus acts as the "dependent variable". An example of a PRP paradigm might be that there is a task 1 which requires participants to push the keyboard-letter 'n' with the right index finger when a square frame was