It’s 11 p.m. on a weekday, and your teen still has the light on in his bedroom. He wants them to get enough sleep for school the next day, but it’s a struggle.
Our new research shows what happens to the brain and behavior of young adolescents, years after they become “night owls.”
We found that this change in sleep pattern increased the risk of behavior problems and delayed brain development in later adolescence.
But it’s not all bad news for night owls.
Change of sleeping habits
people’s dream changing patterns during their teenage years. Teenagers can stay awake longer, fall asleep later, and have a lie the next day.
Many teens also go from being a morning lark to a night owl. They feel more productive and alert later at night, preferring to go to sleep later and wake up later the next day.
This shift to “nightlife” can clash with school and work for teenagers. A chronic lack of sleep, due to these mismatched sleep schedules, may explain why teens who are night owls are at higher risk for emotional and behavioral problems than those who are morning larks.
Emerging research also indicates that morning larks and night owls have a brain structure. This includes differences in both gray and white matter, which have been linked to differences in memory, emotional well-being, attention, and empathy.
Despite these links, it is not clear how this relationship could emerge. Does being a night owl increase the risk of later emotional and behavioral problems? Or do emotional and behavioral problems cause someone to become more of a night owl?
In our study, we tried to answer these questions by following adolescents for many years.
What we did
We asked more than 200 adolescents and their parents to complete a series of questionnaires about adolescent sleep preferences and emotional and behavioral well-being. The participants repeated these questionnaires several times over the next seven years.
The teens also underwent two brain scans, several years apart, to examine their brain development. We focus on mapping changes in the structure of white matter, the connective tissue in the brain that allows our brains to process information and function effectively.
Previous research shows the white matter structure of morning larks and night owls differ. However, our study is the first to examine how changes in sleep preferences might affect white matter growth over time.
This is what we found
Teens who became night owls in early adolescence (around age 12 or 13) were more likely to have behavior problems several years later. This included increased aggression, rule breaking, and antisocial behaviors.
But they were not at increased risk for emotional problems, such as anxiety or moodiness.
Importantly, this relationship did not occur in the reverse direction. In other words, we found that prior emotional and behavioral problems did not play a role in whether an adolescent became more of a morning lark or night owl in late adolescence.
Our research also showed that adolescents who became night owls had a different rate of brain development than adolescents who remained morning larks.
We found that the white matter of the night owls did not increase to the same extent as that of the adolescent morning larks.
We know the growth of white matter. It is important in adolescence to support cognitive, emotional, and behavioral development.
What are the implications?
These findings are based prior investigation showing differences in brain structure between morning larks and night owls. It also builds on earlier research indicating that these changes could arise in adolescence.
Importantly, we show that becoming a night owl increases the risk of experiencing behavioral problems and delayed brain development in later adolescence, and not the other way around.
These findings highlight the importance of focusing on adolescent sleep and wake habits in early adolescence to support their later emotional and behavioral health. We know that getting enough sleep is extremely important for brain and mental health.
Here is some good news
It’s not all bad news for night owls. As our research shows, the preferences of morning larks and night owls are not set in stone. Research indicates that we can modify our sleep preferences and habits.
For example, exposure to light (even artificial light) disrupts our circadian rhythms, which can influence our sleep preferences. Therefore, minimizing exposure to bright lights and screens at night can be one way Modify our preferences and drive to sleep.
light exposure first thing in the morning can also help shift our internal clocks to a more morning-oriented pace. You can encourage your teen to eat breakfast outside, or go out on a balcony or to the garden before going to school or work.