The importance of autonomic discharge emanating from high neural regions rostral to the medulla oblongata on heart rhythm was first recognized in the classical studies by Schiff and Danilewsky during the late nineteenth century. Only in the last two decades, however, has a precise description of these neural effects on heart rhythm become possible. Crucial to these more recent advances have been improvements in technology which have permitted application of discrete electrical stimuli to various regions of the brain as well as continuous monitoring of heart rate and arterial pressure. These studies, reported here, represent a portion of a broader research project carried out in the neurophysiological laboratory of the Medical College of Virginia for a number of years and aimed at clarification of the role of autonomic discharge from higher neural centers on organ function
