A child’s nap is more complicated than it looks:
Today, researchers believe that very young children take naps because so-called sleep pressure builds rapidly in their brains — that is, the need for sleep accumulates so quickly during waking hours that a nap becomes a biological necessity. It is not just a question of how much total sleep that children need in 24 hours. Possibly because of the intense synaptic activity that goes on in their highly active, highly connected brains, young children are less able to tolerate long periods of time awake.
In the early 1980s, Dr. Alexander A. Borbély, a professor of pharmacology at the University of Zurich, Switzerland, posited a “two-process model of sleep regulation.”
The “circadian process,” which has been localized to a specific place in the brain, works a little like a clock, tying our sleep to schedules and to cycles of light and dark, regardless of how much we have or have not slept. This interacts with the “homeostatic process” which works differently, pushing us harder toward sleep the longer we stay awake and building up sleep pressure, which can be measured via EEG recordings.
Napping happens “because children have a much faster sleep homeostasis — they build up sleep pressure more quickly, they are not so tolerant toward longer waking periods,” said Dr. Oskar Jenni, a pediatrician who is director of the child development project at the University Children’s Hospital Zurich.
You see, children take naps because they need naps. Um, yeah, thanks scientists.