When I see children or teenagers with sleep difficulties, the first questions in my mind are, “What is bedtime like? What time is it? How long does it take to fall asleep?” Often, one of the best treatments for insomnia is adjusting the timing of bedtime at night. It does not entail any prescriptions or side effects, just a recalibration in the schedule of the child and the family. The goal of adjusting bedtime is to use the natural need for sleep to address sleep problems.
Why Do You Fall Asleep?
In sleep medicine, we talk about two systems in the body which help people to fall asleep on time. Today we are talking about the homeostatic sleep drive. Although it has a complicated name, it is easy to understand. The longer you stay awake, the sleepier you are. Sleep drive essentially is your likelihood of falling asleep at a given time. Interestingly, this phenomenon is caused by the gradual accumulation of a neurotransmitter called adenosine during the day which is gradually reduce during sleep. The second system is called the circadian system or body clock and I will cover it in a later post.
When you look at sleep drive in a graph, you see that it it increases until you go to sleep, then it slowly decreases until you wake up in the morning.
Sleeping In and Napping Make You Less Tired At Bedtime
Prolonged sleeping in on the weekends is a major problem with teenagers. Although it feels good to catch up on sleep, it can make it nearly impossible to fall asleep on Sunday night, perpetuating the vicious cycle of adolescent sleep. The reason is that sleep drive is reduced at bedtime, as noted in the diagram below.
Younger children require a nap, usually up until age three or four years of age. After that age, a nap, especially a long one, can make it difficult to fall asleep at night. “Sneaky sleep” in a preschooler in the back of Dad’s car on the way home from daycare may sabotage bedtime by reducing sleep drive at night. Likewise, many teenagers are sleep deprived because of structural issues in their schedules and take prolonged afternoon naps.
Staying Up Later Means Falling Asleep Quicker
The reason adjusting bedtime later can help with insomnia is that it harnesses the body’s natural sleep drive to make falling asleep easier. When we move bedtime later in a child, we call that bedtime fading . When we do that in a teenager or adult, we call it sleep restriction, and it is a component of cognitive behavioral therapy for insomnia (CBT-I), the gold standard treatment for insomnia in individuals 18 and up. . Either way, the principle is the same. The key, either way, is ensuring that the wake time does not extend later as well, as the goal is maximizing sleepiness at bedtime.
In the next part of this serious I’m going to talk about the circadian system and how it interacts with sleep drive.
Parents– have you adjusted your children’s bedtime in the context of sleep training? Teenagers– have you found that sleeping in or napping affects your ability to fall asleep at night? Is Sunday a particularly difficult night for you?