<P> The pneumotaxic center, also known as the pontine respiratory group (PRG), is a network of neurons in the rostral dorsal lateral pons . It consists of the subparabrachial nucleus and the medial parabrachial nucleus . It is considered an antagonist to the apneustic center, which produces abnormal breathing during inhalation . It limits inspiration . </P> <P> The PRG antagonizes the apneustic center, cyclically inhibiting inhalation . The PRG limits the burst of action potentials in the phrenic nerve, effectively decreasing the tidal volume and regulating the respiratory rate . Absence of the PRG results in an increase in depth of respiration and a decrease in respiratory rate . </P> <P> The PRG regulates the amount of air a person can take into the body in each breath . The dorsal respiratory group has rhythmic bursts of activity that are constant in duration and interval . When we need to breathe faster, the PRG tells the dorsal respiratory group to speed up . When we need longer breaths the bursts of activity are elongated . All the information that our body uses to help us breath happens in the pneumotaxic center . If this was damaged or in any way harmed it would make breathing on our own almost impossible . One study on this subject was on anesthetized paralyzed cats before and after bivagotomy . Ventilation was monitored in awake and anesthetized cats breathing air or CO2 . Ventilation was monitored both before and after lesions to the pneumotaxic center region and after subsequent bilateral vagotomy . Cats with pontine lesions had a prolonged inhalation duration . In cats, after anaesthesia and bivagotomy, pontine transection has been described as evoking a long sustained inspiratory discharges interrupted by short expiratory pauses . In rats on the other hand, after anaesthesia, bivagotomy and pontine transection, this breathing pattern was not observed, either in vivo or in vitro . These results suggest interspecies differences between rat and cat in the pontine influences on the medullary respiratory generator . </P>

Where are the apneustic and pneumotaxic centers located