Sleep is a problem in most families with a child on the autism spectrum. In fact, a range of studies on sleep disturbance report 53% to 93% of children on the spectrum have sleep problems, most commonly going to sleep.
In addition, when a child on the spectrum does not get enough sleep, that problem often affects the amount of rest the whole family gets. This can create crippling ripple effects.
Circadian Rhythms: A Framework to Analyze Sleep Problems
Circadian rhythms are the cycles of rest and activity, or sleep and alertness, that mark our lives.
In people, these cycles are influenced by the “inner clock” in the almond-sized hypothalamus, and by the pineal gland. The pineal gland produces the sleep hormone, melatonin.
However, circadian rhythms are not determined purely by what is inside us. They interact with factors in the environment, primarily light.
When light enters the eye, it strikes cells in the retina. Some of these cells – rods and cones – are responsible for vision. Other cells, ganglion cells, discovered more recently, are involved in circadian rhythms. When light strikes them, they send a message to the “inner clock,” or “master clock” in the hypothalamus, which collects information about what is going on throughout the body. These ganglion cells tell the hypothalamus it is light outside, and not time to sleep.
This message leads the hypothalamus to tell the pineal gland to suppress the production of melatonin. Then the absence of melatonin makes us want to stay up.
Unfortunately, the ganglion cells, the hypothalamus, and the pineal gland cannot tell the difference between between sunlight, and artificial light. So when light from a street light, lamp, or video game strikes a ganglion cell, it carries a false alarm to the hypothalamus. Then a chain of events ensues that act like a roadblock for getting to sleep.
However, scientists now know why this chain of events is slightly different in children on the spectrum compared with children who are not on the spectrum.
A New Piece in the Puzzle for People on the Spectrum
Recently, in many studies, scientists discovered problems with melatonin among children, and adults, on the spectrum (compared with peers). These problems included consistently lower levels of melatonin, and a delay in the timing of the nighttime melatonin peak.
These abnormalities appeared to be linked to genetic mutations in clock genes – the genes responsible for regulating melatonin.
In other words, people on the spectrum start the process of getting sleepy in the evening with a disadvantage in biology. If getting to sleep were a race, it’s as if other people had a headstart.
Unfortunately, sleep problems are associated with other disadvantages. For example, several studies found insomnia in children on the spectrum correlated with spectrum symptoms, such as:
- repetitive behaviors
- language impairment
- difficulty with reciprocity in relationships.
Another study discovered that children on the spectrum who did not sleep for long were more likely to suffer from depression, obsessive-compulsive disorder, and social limitations, such as the inability to develop a peer relationship.
In general, the more severe the sleep disturbance, the more severe the spectrum symptoms that accompany it.
Fixing a Possible Melatonin Deficit
If children on the spectrum suffer from a melatonin deficit, would melatonin supplements fix the problem? Twenty studies report improvement in some aspect of sleep, such as sleeping longer, fewer nighttime awakenings, and getting to sleep faster.
Other studies have generally had similarly positive results. Sometimes studies even identified additional improvements associated with melatonin, such as better daytime behavior.
Finally, melatonin was safe.
No wonder that although melatonin does not have an indication (approval) from the FDA for insomnia in the spectrum, more than 30% of the physicians in three surveys recommended it. What melatonin doses are best is not clear. For example, CET researchers found that doses far lower than over-the-counter tablets brought melatonin up to the level of healthy young adults. A second problem is that commercial tablets are unpredictable in strength and purity. More research is needed to hone in on the most effective formulations for melatonin.
Helping Your Child Sleep
Melatonin may be a promising tool to help children on the spectrum. For additional information on how you can help your child get to sleep naturally, read Help Your Child Get to Sleep: Three Tips. Like this article, Help Your Child Get to Sleep: Three Tips uses circadian rhythms to provide a useful framework for thinking about ways to help your child get to sleep.
How does exposure to light at night affects children? This page includes a video with the latest findings on preschoolers. There are also links to content on sleep across the lifespan, including Five Tips to Give Your Baby the Best Sleep in the World.
It turns out that it is not only how much light you get. When you, or your child, get that light affects your health, and mental health. Read about some of the latest research.
Why are children more vulnerable to light than adults? What biological changes in adolescents make teens more likely to have difficulty sleeping? When is protective eyewear needed to get a good night’s sleep?
How does melatonin affect sleep? What is melanopsin, and why is it a key part of the system of circadian rhythms? How do these elements fit together for children and adults? A clear explanation puts the pieces together.