The Cardiac-Somatic Relationship

Abstract

To my surprise, the work we began in the mid-1960s observed a direct relationship between HR and somatomotor activities in several behavioral paradigms. This covariation between HR and somatomotor activity is what I call the cardiac-somatic relationship. The surprise came because I had viewed HR as a rather simple, direct index of the behavioral states generated by these paradigms, a measure independent of somatomotor activity. In fact, I had such a primitive understanding of somatomotor activity and related metabolic processes that initially I did not view the HR and somatic changes as integrated aspects of some more global response process that characterizes the cardiac-somatic concept. Rather, I looked at such HR changes as caused by the actual execution of the somatomotor response similar to the manner HR was viewed in the curarization studies concerning visceral learning (Miller, 1969). As such, these HR changes could be considered artifacts, as Smith (1954) proposed was the case for all conditioned autonomic responses.