Brain Rules for Baby (John Medina) / quote 81 of 91
Newborn sleep is nothing like adult sleep
The central fact of newborn sleep is that it is nothing like adult sleep. Instead of gradual cycles of descent and ascent, newborns have only two speeds, christened by sleep researcher Richard Ferber as “active sleep” and “quiet sleep.” Both speeds are established in the womb, detectable by the middle of the third trimester. The presence of just two tempos means infants are only beginning to learn how to sleep. They won’t exhibit a predictable sleep cycle for several months—or adult-like sleep behaviors for years. Sleep for them seems spasmodic, and parents get jerked along for the ride. On a good night, adults ride a smoothly moving elevator. On a good night, babies ride the Tower of Terror. Why? Here’s what researchers know so far: When babies are safely tucked inside their mother’s womb, they may respond to—even follow—mom’s natural biochemical rhythms. This is because they are plugged into the maternal central computer via the placenta and umbilical cord. It’s not just humans. All mammals get warmth, food, water, and hormones (including sleep-regulating melatonin) from mom on a regular basis. At birth, the comforting supply of warmth, food, water, and sleep cues become immediately and violently disconnected. (I literally cut the umbilical cord off both my sons with a pair of sharp scissors.) In this one act, babies become completely out of sync with the cycles of adult existence. The newborn must solve these problems immediately after birth, the most important problem being food. Some researchers think the altered waking/sleeping patterns initially concentrate on getting a consistent food supply. Newborns’ task is Herculean. They need to eat about every two to three hours, some much more often. Consistent with this notion, infant sleep patterns have been shown initially to closely follow feeding patterns: the amount of time it takes babies to consume food, digest food, metabolize food, and then become hungry again. Baby may sleep, but only after the tank has been topped off. Notice that I said “may.” Some babies are energized by food, in which case they are not ready to sleep after a midnight snack; they are ready to play, cry, or otherwise demand attention. So feeding doesn’t always ensure a round of sleep.