PSY230H1 Lecture : An Innate Brain system notes
9
PSY230H1 Full Course Notes
Verified Note
9 documents
Document Summary
Panksepp nurturance in mammals arose from neurochemical processes that controlled egg-laying and mating behavior in reptiles. Vasotocin (precursor to oxytocin) controls sexual urges in reptiles and helps to deliver young reptiles. In mammals, vasotocin evolved into oxytocin and argine-vasopressin (avp), which are important in mating behavior. They differ from vasotocin by one amino acid. Panskepp- oxytocin promotes receptivity in female mammals (lordosis effect in rats) and also prepares the mother"s brain for nurturance. Initial clue was that blood transfused from a rat, which had just given birth, could instigate maternal behavior in a virgin rat. Heightened maternal desire corresponds to the peak of hormonal change, reaching the apex several hours before birth (during this time, rat moms build nests). Estrogen (moderate during pregnancy) rapidly increases as birth nears. Progesterone (high during pregnancy) plummets as birth nears. Increase in prolactin, inducing mom"s acinar glandular tissues to produce milk.
