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
Set the Controls for the Heart of the Sun 1973 at the Stadthalle, Vienna, during the "Dark Side of the Moon" tour. . Live versions of the song appear on the 1969 "Ummagumma" album and the 1972 "" music film. During these live performances, the song was significantly extended with a wide range of dynamics, including a white noise middle section. The song has been a staple in Waters' solo tours. Beginning with the 1984–1985 tours, "Set the Controls for the Heart of the Sun" was presented in a radically rearranged rendition - with female backing vocals, saxophone solos and a guitar solo (and even a shakuhachi solo in