THREE-PART RHYTHM: There are three stages to mammalian breathing: inspiration, passive expiration (postinspiration), and active expiration—a conditional phase used during labored breathing. Inspiration and active expiration have been linked to rhythm-generating excitatory neural circuits in the medulla: the pre-Bötzinger complex and the lateral parafacial region, respectively. A recent study has revealed a third excitatory network—the postinspiratory complex (PiCo)—that drives postinspiration, suggesting that the coordination of breathing may rely on alternating inhibitory interactions between three networks. © SHRADDHA NAYAK
The paper
T.M. Anderson et al., “A novel excitatory circuit for the control of breathing,” Nature, 536:76-80, 2016.
A lot can happen after we take a breath—from swallowing a sip of coffee to singing in the shower—and the nervous system has to coordinate all these behaviors without sending fluids into the lungs or disrupting airflow. But studying the neural control of breathing has been a challenge, not least because researchers haven’t found all the circuitry involved.
Two breathing phases, inspiration and active expiration (the forced expulsion of air during labored breathing), have each been linked to rhythm-generating excitatory networks in the medulla, the lowest portion of the brainstem. But scientists have been stumped as to the source of excitation generating the third: the passive release ...
