NROC61H3 Lecture Notes - Lecture 7: Thyrotropin-Releasing Hormone, Ventromedial Nucleus Of The Hypothalamus, Posterior Pituitary
Document Summary
Lateral hypothalamus as "hunger center" and ventromedial hypothalamus as "satiety center" Control of feeding, drinking, temperature, arousal, sexual behavior/reproduction, etc. Drive theory: motivation of behaviors happen to maintain homeostasis. Violation of homeostasis set point, then we will try to compensate for that violation. Problem: doesn"t explain some motivated behaviors such as maternal behavior, anger/aggression, sex drive. Some behaviors are just out of control and violate homeostasis. Incentive theory: incentive stimulus compel towards actions (motivation) Stepping into cold weather: shivering, huddling, goosebumps (piloerection), blood gets redirected to inner core to maintain temp. (basal constriction) --prevent heat loss and conserve heat. Hormonal response: thyroid releasing hormone gets activated which leads to an increase in metabolism. Very small cluster of nuclei, making up less than 1% of entire brain mass. Nuclei line the 3rd ventricle (form the walls of the 3rd ventricle), which means it has access to csf. Ideally located to predict changes and to subserve regulation of motivation.
