Dysphoric milk ejection reflex sense of depression and this feeling can range from mild homesickness or wistfulness to more intense feelings of hopelessness and self-loathing. Similarly, anxiety may range from restlessness to more intense panic and dread. Anger, the least likely of the three, may range from tension and agitation to more intense feelings of hostility and aggression. The mechanism is not clear. In a mother with D-MER, dopamine may fall inappropriately with milk release, causing the negative feelings. Among the hormones involved in milk production and release are oxytocin, prolactin, and dopamine. Oxytocin, released in pulsatile "spikes" from the posterior pituitary in response
Period (gene) nucleus as well as areas outside the SCN. Additionally, while Drosophila PER moves between the cytoplasm and the nucleus, mammalian PER is more compartmentalized: mPer1 primarily localizes to the nucleus and mPer2 to the cytoplasm. Familial advanced sleep-phase syndrome known to be associated with mutations in the mammalian Per2 gene. People suffering from the disorder have a shorter period and advanced phase where they go to sleep in the early evening (around 7pm) and wake up before sunrise (around 4am). In 2006, a lab in Germany identified particular phosphorylated residues of PER2 that are mutated in people suffering of FASPS.