How do the sleep stages change during ones life span?
As we age, total sleep time decreases and sleep begins to fragment.
The time in sleep declines with age from 16 to 18 hours a day in a newborn to 9 to 10 hours in a 10-year-old, to 7.5 to 8 hours in the average adult, and eventually to 6 hours in an 80-year-old.
A newborn’s sleep is up to 50% REM sleep, and this declines to 25% of sleep by adulthood. There is also a progressive decrease in SWS with aging.
This change in sleep architecture also has endocrine repercussions because specific anterior pituitary hormone release is associated with particular sleep stages