amnion. the innermost fetal membrane, which forms a sac filled with amniotic fluid that surrounds the embryo and later the fetus; as it enlarges it gradually obliterates the chorionic cavity and enfolds the umbilical cord. Called also bag of waters.
cluster breathing. cluster breathing. a breathing pattern in which a closely grouped series of respirations is followed by apnea. The activity is associated with a lesion in the lower pontine region of the brainstem. See also Biot's respiration, Cheyne-Stokes respiration.
Box breathing can teach you how to handle even the most stressful of situations by focusing on deep breathing. Box breathing is one technique used to help combat travel anxiety, whether it's fear of flying or driving in heavy traffic, and can also help students fight test-tasking anxiety.