Dysphoric milk ejection reflex to nipple/areolar stimulation, thoughts of the baby or of breastfeeding, or overfull breasts, travels through both brain and bloodstream, causing emotional changes in the brain and the release of milk in the breast. Prolactin, released in a gradual wave that peaks after the beginning of a feeding, is responsible for continued milk production. Dopamine inhibits the release of prolactin, so dopamine levels must drop in order for prolactin levels to rise. Some speculate that the necessary dopamine drop is similar to (and timed with) the oxytocin spike – a sort of negative image – but that in D-MER mothers it
Refractory period (physiology) potential cannot be elicited. During the relative refractory period, a new action potential can be elicited under the correct circumstances. The cardiac refractory period can result in different forms of "re-entry", which are a cause of tachycardia. Vortices of excitation in the myocardium (autowave vortices) are a form of "re-entry". Such vortices can be a mechanism of life-threatening cardiac arrhythmias. In particular, the autowave reverberator, more commonly referred to as spiral waves or rotors, can be found within the atria and may be a cause of atrial fibrillation. The refractory period in a neuron occurs after an action potential and