A center present in the medulla region of the brain called respiratory rhythm center and it is primarily responsible for respiration regulation. And another center which is present in the pons region of the brain called pneumotaxic center. It can moderate the functions of the respiratory rhythm center. The neural signal from this center can reduce the duration of inspiration and thereby alter the respiratory rate.
A chemosensitive area is situated adjacent to the rhythm center which is highly sensitive to CO 2 and hydrogen ions. Increase in these substances can activate this center, which in turn can signal the rhythm center to make necessary adjustments in the respiratory process by which these substances can be eliminated. Receptors associated with aortic arch and carotid artery also can recognize changes in CO 2 and H + concentration and send necessary signals to the rhythm center for remedial actions. The role of oxygen in the regulation of respiratory rhythm is quite insignificant.