Heart rate persons with coronary artery disease. The heart rate is rhythmically generated by the sinoatrial node. It is also influenced by central factors through sympathetic and parasympathetic nerves. Nervous influence over the heartrate is centralized within the two paired cardiovascular centres of the medulla oblongata. The cardioaccelerator regions stimulate activity via sympathetic stimulation of the cardioaccelerator nerves, and the cardioinhibitory centers decrease heart activity via parasympathetic stimulation as one component of the vagus nerve. During rest, both centers provide slight stimulation to the heart, contributing to autonomic tone. This is a similar concept to tone in skeletal muscles. Normally, vagal stimulation
Decade of the Brain Decade of the Brain The Decade of the Brain was a designation for 1990–1999 by U.S. president George H. W. Bush as part of a larger effort involving the Library of Congress and the National Institute of Mental Health of the National Institutes of Health "to enhance public awareness of the benefits to be derived from brain research". The interagency initiative was conducted through a variety of activities including publications and programs aimed at introducing members of Congress, their staffs, and the general public to cutting-edge research on the human brain and encouraging public dialog on the ethical, philosophical, and