Cardiovascular reactivity as behavior

The word, behavior, means action or reaction. Thus, all physiologic responses meet this definition and are behavior. Furthermore, if the response is neurally mediated, then there are only 3 possible behavioral mechanisms that can be operating to determine it: (1) The response is part of a reflex, elicited by an adequate stimulus. In this case, in an intact animal the expression of the response will be modulated by a variety of situational factors. (2) The response is part of a reflex. However, the capacity of the stimulus to elicit the response is acquired through association with an adequate stimulus. Thus, the reflex is learned rather than innate. (3) The response is part of a "central command" and is emitted in anticipation of a consequence whose likelihood of occurrence has been learned. Neurally mediated responses of the circulation meet all these criteria. Thus, circulatory responses not only are passive reflexes, they also are reactive and proactive behaviors, which permit animals to interact effectively with their environments, and which change with practice. These principles explain a variety of cardiovascular effects observed in experimental or clinical settings. Furthermore, by applying well-established behavioral principles to circulatory responses, it is possible to achieve clinically significant effects. This presentation will characterize the way in which behavioral mechanisms are expressed in the circulation, it will describe a number of clinically significant findings that illustrate the importance of these mechanisms, and it will propose a number of applications of behavioral principles that can be used in clinical practice.