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Sleep mysteries in babies—as in adults—abound. To begin with, no one knows why exactly humans of any age need shut-eye. Does the fetus build visual circuitry in utero during REM, well before its eyes open? Are babies' REM sleep-patterns a form of protection against SIDS?
It's likely that babies rely on sleep for the same (uncertain) functions as adults, as well as some additional ones related to brain development. And we know for sure that dreamland can be painfully elusive at any age. Some tips, like keeping the bedroom dark and quiet and winding down before sleep, seem to help across the generations. But, confusingly, others that promise better sleep for you don't necessarily work for a baby or toddler. To some degree, babies have different patterns and different relationships to shut-eye than adults do. Which may explain why they need sleep tricks of their own.
For adults with chronic insomnia, cognitive behavioral therapy is a proven treatment—more effective, in some research, than sleeping pills. The approach includes some common-sense moves, like avoiding noise and light in the bedroom and skipping the 9 p.m. espresso. It also involves tricks at a higher degree of difficulty: Experts suggest delaying bedtime until the hour you normally fall asleep, for instance, even if that's late (and then gradually moving the time earlier). They also advise getting out of bed in the middle of the night if you wake up and can't fall back to sleep within 15 or 20 minutes. (You're supposed to do something boring around the house, get drowsy again, and only then return to bed.) The idea is to avoid staring at the ceiling, anxious and alert. Also key is foregoing long naps. That's because daytime snoozing that lasts more than 25 minutes tends to decrease the amount of deep, delta-wave sleep that night, some research suggests. Finally, the therapy tries to weed out negative thoughts and anxieties about sleep—like, "My life is ruined if I don't fall asleep right now, damnit!"
Some of this applies to babies and toddlers: They, too, sleep better without bright lights and noise in the bedroom. (Duh.) They also benefit from a soothing bedtime routine, especially a super-consistent one. A sample wind-down for a nursing infant might include, say, boob, bath, book, and bed, always in that order: "Your child will be more relaxed if she knows what's coming next," writes Jodi Mindell, associate director of the Sleep Center at the Children's Hospital of Philadelphia.
Beyond these basics, though, adults and babies part company. The standard suggestion for adults to push bedtime back in order to consolidate sleep is not unheard of, but it's much less common for babies and toddlers. Sleep experts often suggest moving bedtime earlier to help young children fall asleep. The idea is to make sleep more continuous, and also to help avoid too-early wake-ups. It may sound paradoxical that putting a child to bed early will help him sleep later, but that's adult-think: When babies and toddlers get overtired, they become agitated and wired. They have more trouble settling down, and their eventual slumber is more fragmented, Mindell says. In a national study of roughly 1,500 families with children ranging from infants to 10-year-olds, she found that a bedtime after 9 p.m. was linked to a longer time spent falling asleep and less nighttime sleep in total. (Of course, this does not prove that earlier bedtime causes better sleep—only that there's a correlation.)
Daytime naps, too, seem in tune with most babies' nighttime shut-eye. In a study conducted by sleep expert Marc Weissbluth, 3-year-olds who napped slept around 10.5 hours per night. So did 3-year-olds who didn't nap. The difference was that the nappers got roughly two extra hours of sleep per day. They were also, apparently, "more fun to be around, more sociable and less demanding." Again, it's unclear whether napping actually caused better behavior, but it sounds pretty good—your kid sleeps more and is not a little monster.
What about infant and toddler sleep might explain the difference in the maneuvers that work with them? The drive to sleep builds up more quickly, with the brain simply demanding slumber in fewer hours after waking up. Infants have different natural 24-hour distributions of sleep, as well. As bleary new parents know, baby sleep is distributed throughout the day and night at first, then usually becomes more consolidated at night as the months go by. (If your child is one of the exceptions, you have my sympathy.) In infants, a morning nap can often come only a couple of hours after wake-up time, while the stretch between an afternoon nap and bedtime can typically be longer, says Avi Sadeh, Director of the Children's Sleep Laboratory at Tel Aviv University. Infant naps also tend to consist of more REM sleep than adult naps do, with morning naps especially high in REM; they may function as a coda to nighttime sleep.
Ah, but what you really want to know is what this all means for how to deal with a baby who wakes in the night, right? Avid sleep-trainers frown on taking a sleepless child out of his crib or bed in the middle of the night (except if an infant is very young or sick). That advice about puttering around the kitchen or folding laundry to relax and get sleepy again? Remember, it's for adults only. Parents who turn 2 a.m. into a party may end up with longer and more frequent rendezvous on their hands. (Babies who share a bed with their parents tend to wake up more often in the middle of the night as well, with qualifications.)
Unlike adults, who may have years of anxious tossing and turning to overcome, infants don't have an insomniac history. The cognitive part of adult therapy doesn't really apply. So, in one sense, sleep training for babies and toddlers should be less of an ordeal. The hardest part may be getting parents to trust it and stick with it. Then again, don't be too hard on us. Some parents are just softies, and some kids are insomniacs-in-training, whatever the experts say!