The cardiovascular centre is a part of the human brain responsible for the regulation of the rate at which the heart beats. It is found in the medulla. Normally, the heart beats without nervous control, but in some situations (e.g., exercise, body trauma), the cardiovascular centre is responsible for altering the rate at which the heart beats. It also mediates respiratory sinus arrhythmia. The cardiovascular centre effects changes to the heart rate via sympathetic fibres (to speed up the heart rate) and the vagus nerve (to slow down the heart rate). The accelerator and vagus nerves both connect to the sinoatrial node (SA node). The cardiovascular centre also increases the stroke volume of the heart (that is, the amount of blood it pumps). These two changes help to regulate the cardiac output, so that a sufficient amount of blood reaches tissue.
Hormones like adrenaline can affect the cardiovascular centre and cause it to increase the rate of impulses sent to the sinoatrial node, or "cardiac pacemaker", thus increasing the rate of the heart beat.
Chemoreceptors may also prompt this regulation.
Famous quotes containing the word centre:
“To live and die amongst foreigners may seem less absurd than to live persecuted or tortured by ones fellow countrymen.... But to emigrate is always to dismantle the centre of the world, and so to move into a lost, disoriented one of fragments.”
—John Berger (b. 1926)