PSYCH361 Chapter Notes - Chapter 13: Walter Bradford Cannon, Adrenal Medulla, Autonomic Nervous System
Claude bernard realized that the brain had circuits that were specialized for monitoring and controlling internal events, which he referred to as the internal milieux i. e. thirst, temperature, and metabolism. Walter cannon developed the concept of homeostasis our physiological system tends to center on a set point: stress was the situation in which these systems deviated away from the set point. The brain has two major pathways by which it influences peripheral physiology. The first is the autonomic nervous system, which innervates a variety of organs including the adrenal medulla, which results in the release of catecholamines from the sympathetic nerves prepare the body for actions. The second pathway involves cells in the hypothalamus, which are released into the bloodstream and go to the pituitary gland. This causes the pituitary to release hormones that influence other hormones, which in turn influence peripheral organs such as the adrenals, as well as cells in the immune system.