PSYC1023 Lecture Notes - Lecture 4: Twin, Blood Sugar, Classical Conditioning
Document Summary
Drive theories: internal tensions (like hunger), motivate organisms to achieve. Homeostasis is like a steady state our body keeps a certain amount of calories to maintain that steady state (ex: hunger pains, body temperature with shivering and sweating) Incentive theories: organisms try to acquire external incentives (pull vs push) Imagine you are full, homeostasis is achieved but then there is a desert menus and that is the attractive external incentive. Evolutionary theories: motives are adaptive and maximises reproduction success. Stomach contractions are not critical because those who have their stomachs removed can still experience hunger. The brain controls hunger especially the lateral go" and ventromedial stop" hypothalamus. Go" region basically pushes organisms to eat more and vice versa for stop". Lesions are damages to the brain through electricity. Vmh lesion leads to weight gain, there is nothing to stop them from eating. Lh lesions leads to weight loss, the weight is stabilised after a while.
