We are just getting started on a brand new project to discover how contextual information encoded in the brain prepares the body for upcoming stresses by changing physiology before they occur. This type of anticipation of protects us by changing our respiration, metabolism or autonomic function before we actually encounter a challenge from the environment. When expected changes don’t occur, or when we aren’t expecting a challenge we are tolerant to in a different environment, our physiology can be either adjusted inappropriately (as in drug withdrawal when an expected drug isn’t there) or not adjusted enough (as in decreased drug tolerance in a new environment). We propose that cholinergic mechanisms in the brain, autonomic nervous system and end organs in the body are involved in the coordination of these brain-body interactions.