Healthy Sleep Habits, Happy Child Read online

  Understanding that the rhythms of night sleep, daytime sleep, and daytime wakefulness are somewhat independent from one another leads to two important ideas.

  First, in a child under three or four months of age, these rhythms are not in synchrony with each other, and the baby may be getting opposing messages from different parts of the brain. The sleep rhythm says “deep sleep,” while the wake rhythm says “alert” instead of “drowsy.” Wakeful but tired, the confused child cries fitfully; we might call this behavior colic or fussiness. Opposing messages from different parts of the brain may cause ambiguous stages such as sleep inertia. In research with adults and animals, this has been called “dissociated states of wakefulness and sleep,” or “Status Dissociatus.” For example, some birds can swim or fly when they are completely asleep! Narcolepsy is the intrusion of REM sleep into wakefulness. Sleepwalking, night terrors, and crying out at night occur during the overlap state of wakefulness and non-REM sleep. Because adult wake/sleep states may overlap, be incomplete, or switch rapidly between states, it is entirely possible that during the first four months, when sleep states are developing, partial states express themselves out of phase and with other states, creating overlap problems that we refer to as fussiness, colic, or sleep inertia. For example, it is known that babies can suck, smile, and cry with their eyes open during REM sleep, so while they appear to be awake, they are actually asleep. We can call this “indeterminate sleep” or “ambiguous sleep,” which reflects the immaturity of the young brain. After about four months of age, these ambiguous states are less common.

  Second, if these sleep/wake rhythms are somewhat independent, they may have different functions: learning for the wake cycle, physical and emotional restoration for the sleep cycle. Daytime sleep and nighttime sleep may be different in this regard. I believe that healthy naps lead to optimal daytime alertness for learning—that is, naps adjust the alert/drowsy control to just the right setting for optimal daytime arousal. Without naps, the child is too drowsy to learn well. Also, when chronically sleep-deprived, the fatigued child becomes fitfully fussy or hyperalert in order to fight sleep, and therefore cannot learn from his environment.

  Not only are naps different from night sleep, but not every nap is created equal. There is more REM sleep in the morning nap compared to the afternoon nap. Research suggests that high amounts of REM sleep, under the influence of low melatonin levels, help direct the course of brain maturation in early life. Also, adult studies have suggested that REM sleep is especially important for restoring us emotionally or psychologically, while deep, non-REM sleep appears to be more important for physical restoration. Let's get all the REM sleep we can for our babies!

  Because naps have their own function and do their job best when they occur at the right time, I suggest that if a nap has been missed, try to keep your child up until the next sleep period in order to maintain the timeliness of the sleep rhythm. This suggestion has to be balanced with the general theme of avoiding the overtired state, so the next sleep period (nap or night) might begin a little earlier.

  My studies show that at four months of age, most children take either two or three naps. The third nap, if taken, tends to be brief and in the early evening. But by six months of age, the vast majority of children (84 percent) are taking only two naps; by nine months of age virtually all children are taking just one or two naps. About 17 percent of children have started taking only a single nap by their first birthday, and this percentage increases to 56 percent by the age of fifteen months. By twenty-one months, most children are down to just a single nap.

  The morning nap develops before the afternoon nap, but it also disappears before the afternoon nap. The single nap that is present by twenty-one months and resurfaces in adolescence or adulthood is always the afternoon nap. Infants and young children have much more REM sleep at night than older children, and the morning nap has more REM sleep than the afternoon nap; this suggests that in some infants, the morning nap may be viewed as a sort of continuation of night sleep. Later I will discuss how we can help babies sleep better by keeping the interval of wakefulness between the wake-up time and the start of the first nap very short. This strategy may work because we are really allowing night sleep to continue longer.

  Another thing that I've discovered is that up until about twenty-one months of age, some babies are born to be short nappers and some are inherently long nappers.

  IMPORTANT POINT

  Not all sleep periods are created equal!

  Parents can interfere with a child's long naps by messing up the child's schedule, but they cannot make short nappers into long nappers. Here are some important facts about short nappers: At six months of age, 80 percent of babies nap between two and a half and four hours total each day. Napping more than four total hours each day occurs in 15 percent of babies. However, in 5 percent of babies, the total daytime sleep each day is less than two and a half hours. If you look at brief naps slightly differently and include babies who sleep a total of two and a half hours or less each day, then 18 percent of babies fall into this category. These short nappers tend to keep this pattern for the next twelve to eighteen months! This truth is especially frustrating to mothers whose first child was a long napper and they remember having long breaks during the day to do whatever they wanted. If their second child is a short napper, they may incorrectly think they are doing something wrong.

  If parents can cause problems that interfere with good naps, why can't parents make their babies sleep longer? This question provides a good example of the asymmetry between sleep and wakefulness. Sleep is not the absence of wakefulness; rather, the brain automatically and actively turns on the sleep process and simultaneously turns off wakefulness. You, and your child, can force wakefulness upon sleep, but you cannot force sleep upon wakefulness. You, and your child, can motivate or force yourself and him into a more wakeful or alert state, but you cannot will anyone into a deeper sleep state. So sleep and wake states are different but not opposite. Parents have the opportunity to permit the maximum amount of sleep to occur; this amount reflects their child's actual need for sleep. As stated before, a baby's nap pattern is largely an individual trait that stays stable until about twenty-one months.

  Evidence of the individuality of this trait comes from studies on twins and argues for a strong genetic component to the control of sleep in babies. An obvious example occurs when one twin is a short napper and the other twin is a long napper—more about that later. At twenty-one months, the average nap duration is a little less than two and a half hours, but the range is wide: between one and four hours. At this age, some of the children who initially took brief naps are now taking longer naps, and some who had been long nappers are now taking briefer naps. My interpretation is that by twenty-one months, biology is no longer the primary influence on napping; social factors begin to play a role. For example, events such as the birth of a sibling, an older sibling starting preschool, or the child herself now participating in organized and scheduled activities can cause children who have a biological need for longer naps to take shorter naps. Often, no problems occur if catch-up days are provided coupled with an extra-early bedtime.

  The time of day when the nap occurs is also important. Some studies have suggested that an early nap, occurring in the midmorning hours, is different in quality from a later nap, which occurs in the afternoon. As mentioned before, there is more active REM sleep than quiet sleep in the first nap, and this pattern is reversed in the second nap. So naps occurring at different times are different! Even for adults, a nap earlier in the day is lighter and less restorative than an afternoon nap, which consists of deeper sleep.

  Long naps occurring at the right time make the child feel rested. Levels of cortisol, a hormone that increases with stress, dramatically fall during a nap, indicating a reduction of stress in the body. Not taking a needed nap means that the body remains stressed. Brief naps or naps that are out of synchrony with other biological rhythms are less restful, less restorativ
e. But a short nap is better than no nap. It still has a positive effect on alertness.

  Children can be taught how to take naps. A nap does not begin and end the way an electric light can be turned off and on. In fact, a nap or night sleep involves three periods of time: the time required for the process called falling asleep, the sleep period itself, and the time required to wake up. One father complained to me, “I can't see the pre-Zs coming out of his head,” meaning he had difficulty seeing the lull in activity or quieting that precedes sleep. In later chapters I will show you how to recognize the “pre-Zs” and teach your children to fall asleep.

  PRACTICAL POINT

  Do not expect your baby to nap well outside his crib after four months of age. If you don't protect your baby's nap schedules, you can produce nap deprivation.

  When children do not nap well, they pay a price. Infants between four and eight months who do not nap well have shorter attention spans or appear less persistent when engaged in activities. By three years of age, children who do not nap or who nap very little are often described as nonadaptable or even hyperactive. Adaptability is thought to be a very important trait for school success.

  One mother of a nonadaptable child said with a laugh that every morning she prayed to the “nap god” to give her a break. In contrast, another mother described her son as a very easy child as long as she had a bed around. He was such a “rack-monster” that she decided he just liked his own company best. Another mother described her son, who napped well, as the “snooze king.”

  Sometimes it appears that the older toddler needs exactly one and a half naps. While one nap is insufficient, two are impossible to achieve. These children are rough around the edges in the late afternoon or early evening, but parents can temporarily and partially compensate by putting the child to bed earlier on some nights.

  An earlier bedtime may become a necessity when your child develops a single-nap pattern, between fifteen and twenty-one months. Earlier bedtimes help prevent bedtime battles, deter night waking, discourage extremely early morning awakenings, and regularize and prolong naps. Why, then, do many parents resist the notion of putting their children to sleep when they first appear tired at night, even though it is clear that the brain is sleep-sensitive? First, parents naturally want to be with their children and play with them. Second, there is a powerful inhibitory fear that if their child is put to bed very early when tired, she will get up extra early the next day. Third, because I recommend that, along with an earlier bedtime, the parents not go to the child at night, except for feeding, parents are naturally frightened about the possibility of prolonged crying when they put the child to bed or in the middle of the night. This fear of possible crying discourages parents from trying for an earlier bedtime.

  Here is an example of how a family started early, at eight weeks of age, to focus on an earlier bedtime. The baby was not overtired and did not have extreme fussiness/colic, so the transition went smoothly. For 20 percent of babies with extreme fussiness/colic, this easy change to an earlier bedtime at eight weeks of age is not realistic.

  JADEN'S STORY

  When our daughter Jaden was born, we were anxious to start off on the right foot with her sleep habits. We immediately focused on no more than two hours of wakefulness with a bedtime around 10:00 or 11:00 P.M., which was very easy to accomplish. After a few weeks, though, we still weren't really seeing very long nighttime stretches. When Jaden was eight weeks old, we visited Dr. Weissbluth to discuss her sleeping pattern. Dr. Weissbluth told us that at six weeks, we should have incorporated an early bedtime in addition to keeping shorter periods of wakefulness. We left wondering whether an early bedtime would really work for someone so young. We really expected that Jaden would be up within an hour or two after we put her down. We started off with a 7:00 P.M. bedtime. She still woke up in the late evening to eat, but we put her promptly back to bed. There were a few bumps in the road for the first couple of nights—sometimes she would wake up a few times and cry—but we kept at it. After a few days, Jaden went from sleeping a four-to five-hour stretch in the evening, to seven, then eight, then nine or ten hours a night. In fact, she seemed happy to be sleeping so much! If she woke up to nurse, she would eat and immediately fall back asleep as soon as we put her back in her crib. We couldn't believe how easy it was. The earlier we got her to bed, the better she slept. Her daytime naps even seemed longer and more restful. She is now seven months old. We now try to get her down between 6:00 and 6:30 each night, and she is extremely happy about it. (So are we!)

  Over and over again I have seen children who are put to bed too late. It becomes a vicious circle: The child's nap schedule is messed up, and the child is fussy in the late afternoon or early evening. This fatigue-driven fussiness ends in a wired state at bedtime, which interferes with the ability to go to sleep easily. As a result, the parent keeps the child up until he crashes. The next day the child is still tired, the naps are messed up, and so on. The circle never ends.

  The solution is obvious in Meg's story.

  MEG'S EARLY BEDTIME

  Our daughter Meg has been a good sleeper from the very beginning. Since she was six weeks old she has gone weeks when she would sleep through the night (from 10:00 to 6:00), and weeks when she would wake up twice to nurse.

  At seven months, she began waking once a night for a bottle. This was fine until she turned eight months old. We had been told by a doctor that she should no longer need to eat in the middle of the night, but we thought we would wait until Meg's nine-month appointment with Dr. Weissbluth to address the problem.

  We had never been very consistent with Meg's bedtime. We would put her to bed when she appeared tired (rubbing eyes, yawning), anywhere from 7:00 to 7:45, but occasionally even later. It usually took her between fifteen and thirty minutes of crying to fall asleep. I thought this was normal. She had always gone to bed rather late and she had always taken a while to fall asleep.

  At Meg's nine-month appointment we asked Dr. Weissbluth about her night waking. He made a very simple suggestion. He told us that we should put Meg to bed twenty minutes earlier at night. He said that her night waking would disappear and she would still wake up at a normal hour in the morning. I told him that we had been putting her to sleep when she appeared tired at around 7:30, give or take thirty minutes. He said that once she appears tired it is too late and she should already be in bed.

  The first night we put her to bed at 6:45. We were very skeptical. We were sad to put her down so early when she seemed so wide awake and happy. She cried for about five minutes and then fell asleep, and with no night waking! The same thing happened the next night—about five minutes of crying and then asleep until morning. Sometimes she would wake up as early as 5:30, but we would give her a bottle and she would fall back to sleep, sometimes until almost 8:00!

  It has been almost four weeks since our nine-month appointment. Bedtime is an absolute joy. Meg eats dinner, takes a bath, and is in bed about 6:30. Sometimes I hesitate to put her down so early when she seems to be in such good spirits, but she cuddles with her blanket and her doll, sucks her thumb, closes her eyes, and sleeps till morning. It's the sweetest thing I have ever seen.

  As Meg's parents said about my recommendation for a much earlier bedtime, “He made a very simple suggestion.” Sometimes simple approaches work better than complex solutions. Here's another example.

  JARED'S SLEEP STORY

  When we met with Dr. Weissbluth, Jared, now nineteen months old, was waking up every hour and a half to two hours during the night. He would have to fall asleep while we were walking and carrying him on our shoulder. When placed in the crib, Jared would awaken and abruptly “pop up.” He would only sleep in the bed “nest” we created for him on the floor of our family room. We endured three months of the night waking before we consulted Dr. Weissbluth.

  We were instructed to place Jared in bed in an awake state between 6:00 and 7:00 in the evening and that we should leave him there until 6:00 in the morning. Our ini
tial reaction was that Jared would carry on relentlessly when placed in his crib so early, and that the recommended approach was too strict and would never work. Much to our shock and delight, the first night we tried the new routine, Jared was asleep after five minutes of crying, and remained asleep for eleven hours, not waking until 5:30 the next morning. During the next two nights, Jared went to sleep on his own, with no episodes of crying. On the fourth night, he lay down in the bed with his favorite stuffed animal under his arm, as he has done since. Our baby was clearly overtired from going to bed at 8:30 and not being allowed to relax and go to sleep without interference. We never expected it to be so simple and provide such an immediate result. Jared wakes up happy, energized, and ready for a day full of adventures. Now, several months later, Jared is most happy when going to bed at 6:30, and will go to his bed himself if he is tired.

  Probably the most common worry is that the earlier bedtime will produce an earlier wake-up time, as expressed by Anna's story.