Controls vital functions like blood pressure, heart rate, respiration, digestion. First part of brain to evolve. Part of brainstem - helps with body's autonomic functions and reflexes. Respiration, heart rate, swallowing, digestion. Relay station for nerve signals to and from the brain. Part of brainstem - Relays sensory information, helps control autonomic functions and has a role in levels of arousal or consciousness and sleep.
n. 1. (Philosophy) the traditional philosophical problem concerning the nature of mind, body, and the relationship between them. See dualism 2, interactionism, parallelism 3, monism 1, idealism 3, materialism 2, identity theory, behaviourism 2.
Also, the mind and body are actually all one entity, one system. They are interconnected in a mind-boggling number of ways. For example the brain - through the nervous system - extends all the way to the tips of your fingers and toes. The brain is a part of the body.