
01 Sep Irregular Sleeping Patterns Linked to Poorer Academic Performance in College Students
There has been a great deal of research demonstrating that the amount and quality of sleep we get affects our mental performance, mood and overall health. A new study that measured sleep and circadian rhythms, and the association to academic performance in college students found that irregular patterns of sleep and wakefulness correlated with lower grade point average, delayed sleep/wake timing, and delayed release of the sleep-promoting hormone melatonin.
Researchers studied 61 full-time undergraduates from Harvard College for 30 days using sleep diaries. They examined the relationship between sleep regularity, sleep duration, distribution of sleep across the day, and academic performance during one semester. The results indicated that going to sleep and waking up at approximately the same time is as important as the number of hours students slept. Students with more regular sleep patterns had better school grades on average.
Interestingly, researchers found no significant difference in average amount of time students slept. But it was as if the body clock was shifted nearly three hours later in students with irregular sleep. For the students whose sleep and wake times were inconsistent, classes and exams that were scheduled for 9 a.m. felt like they were occurring at 6 a.m. according to their body clock, at a time when performance is impaired.
By measuring the timing of melatonin release at sleep onset, the researchers were able to assess the timing of circadian rhythms. On average, melatonin was released 2.6 hours later in students with the most irregular sleep patterns. The difference in circadian timing between irregular sleepers and students with regular sleep patterns was consistent with their different patterns of daily light exposure. In particular, regular sleepers got significantly higher light levels during the daytime, and significantly lower light levels at night than irregular sleepers who slept more during daytime hours and less during nighttime hours.
Researchers note that the circadian clock takes time to adjust to schedule changes, and is highly sensitive to patterns of light exposure. Irregular sleepers, who frequently changed the pattern of when they slept and consequently their pattern of light-dark exposure, experienced misalignment between the circadian system and the sleep-wake cycle. Researchers conclude that light based interventions, including increased exposure to daytime light and less exposure to electronic light-emitting devices before bedtime, may be effective in improving sleep regularity.
Authored By: Kiara Moore, PhD, LMSW
Sources: Andrew J. K. Phillips, William M. Clerx, Conor S. O’Brien, Akane Sano, Laura K. Barger, Rosalind W. Picard, Steven W. Lockley, Elizabeth B. Klerman, Charles A. Czeisler. Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing. Scientific Reports, 2017; 7 (1)