A few extra minutes of sleep may provide a big boost to teens’ learning ability, says a new study that raises important questions about the impact of sleep deprivation on the young mind.
Researchers in Hong Kong embarked on a study involving more than 1,100 elementary school students to find out what effect – if any – a delayed school start time had on teen behavior.
The researchers divided the students into two groups and had one of the group’s elementary schools push its start time back from 7:45 a.m. to 8:00 a.m. – a modest delay of 15 minutes. The group at the other elementary school maintained their regular start time.
Among a range of positive findings associated with the later start time, the researchers discovered that kids whose school day began later than usual experienced:
- Improved mental health
- Better “prosocial behaviors” and enhanced “peer relationship”
- Increased attentiveness
- Fewer “emotional problems” and decreased “behavioral difficulties”
“A modest delay of 15 minutes in the school start schedule could result in a constellation of benefits across sleep, mood, behavior, and school attendance among adolescents,” conclude the study authors, who are associated with The Chinese University of Hong Kong, in the journal Sleep Medicine.
The authors reported that teens in the group with the delayed start time spent more time in bed and “significantly delayed their weekday wakeup time,” despite the later start of just a quarter hour. The control group, which maintained the same school start time as prior to the study, did not produce similar results.
The authors say that more sleep led to a “corresponding improvement in mood and behaviors.”
An “Epidemic” of Sleep Deprivation
Lack of sleep among teenagers is no trivial matter. A recent study from Stanford Medicine, which calls “sleep deprivation an epidemic” among teens, found a wide range of negative benefits on general health, learning and even morbidity.
“Sleep deprivation increases the likelihood teens will suffer myriad negative consequences, including an inability to concentrate, poor grades, drowsy-driving incidents, anxiety, depression, thoughts of suicide and even suicide attempts,” states the study.
The new study may add to the growing body of evidence suggesting that changes to school start times can bring significant benefits.
“Current findings have significant implications for the education policy, suggesting that school administrators and policy makers should systematically consider delaying school start time to promote sleep and health among school-aged adolescents,” write the researchers.
The vast majority of high school students – about 87 percent – don’t get the eight to 10 hours of sleep every night that experts recommend, notes the Stanford study. The pressure of school, homework and other factors, such as social media use, may be contributing to the large sleep deficit facing many teens.
Another factor is simple biology. A study from the Child Mind Institute notes that production of melatonin – the hormone that regulates sleep – changes in the teen years, leading to later bedtimes and a changing sleep schedule.
Some researchers think that school start times should be pushed back to 8:30 a.m. or later, according to a study from the American Psychological Association. Yet that study notes that only one in five students begins their day at that time or later.