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
Neomammalian brain essential in regulating heart rate, body temperature and space orientation. For example, if a human holds their breath and carbon dioxide levels rise, the primitive brain initiates the lungs to start breathing to achieve a state of homeostasis. The Paleomammalian brain is known as the intermediate or ‘old mammalian’ brain. The Paleomammalian brain anatomically consists of the hypothalamus, amygdala and the hippocampus. It is responsible for subconscious emotions such as fear, joy, fighting and sexual behaviour. The old mammalian brain is found in a large percentage of mammals and is believed to have a strong intricate connection with the neocortex.