Nerve endings in the walls of the carotid sinuses and the aortic arch transduce arterial pressure changes and provide the central nervous system with a steady stream of encoded information. On the basis of this information, efferent autonomic neural activity is modulated finely, and the neurohumoral milieu of the heart and the blood vessels is adjusted on a second-to-second basis. The arterial baroreflex may be the most important of the cardiovascular...