Breathing stops for periods of 20 seconds to 2 minutes. Need for oxygen becomes intense. Person wakes a little and gulps air. Settles back to sleep. Breathing stops again.
Cycle is repeated hundreds of times a night.
Daytime sleepiness, caused by sleep apnea or insomnia. Sudden infant death syndrone. Most frequent cause of death for infants under l year of age. Might be apnea due to immature breathing centers in the brainstem. Maybe a defect that stalls the heart during sleep.