Staying up all night to cram for exams is a time-honored practice among students, and while I don’t think it’s a good idea, most of them make it through their studies with their health intact. These all-night study sessions used to be fueled by coffee or cokes, but I understand that many students now rely on multiple energy drinks with their hefty doses of caffeine to stay awake. That’s not a good plan, since ingesting more than 250 mg of caffeine can get you too wired to concentrate, apart from causing other symptoms, ranging from restlessness, increased urination and muscle twitching to rapid heartbeat and even cardiac arrhythmia.
Even without the effects of excess caffeine, research has shown that all-nighters don’t pay off in the long run. A study from St. Lawrence University in Canton, N.Y. showed that two-thirds of students reported pulling at least one all-nighter per semester and those who said they did it regularly had lower GPAs than students who got some sleep before their exams. A small proportion of students who said they regularly pull all-nighters did maintain high GPAs, but Pamela V. Thacher, Ph.D., an associate professor of psychology who conducted the research, found that percentage more the exception than the rule.
She concluded that pulling all-nighters compromises students’ sleep overall, making it difficult for them to reach their full academic potential. Beyond that, she noted that the short-term side effects of sleep deprivation include delayed reactions and tendencies to make mistakes. For the study Dr. Thacher examined the transcripts and reported sleeping patterns of 111 students.
We know that memory is consolidated during sleep, so students who stay awake to cram all night may be sabotaging their own grades. Exactly how that memory consolidation occurs hasn’t been determined, although a recent (2015) study from a team of graduate students at Brandeis University shed some light on the process. The students set out to learn whether memory is consolidated during sleep because the brain is quiet or whether neurons that consolidate memory actually put us to sleep.
The Brandeis research focused on dorsal paired medial (DPM) neurons known to consolidate memory in fruit flies. The team found that when these neurons were activated, the flies slept more, and when the neurons were deactivated, the flies were up and buzzing. It appears that the memory-consolidating neurons actually inhibit wakefulness as they start converting short-term to long-term memory. This happens in a part of the fly brain called the mushroom body, similar to the hippocampus in the human brain where our memories are stored.
Students may not be the only ones pulling all-nighters these days. I’ve read that the practice is increasing in the business world and that even teachers sometimes can’t avoid it. According to the BBC, a 2012 survey in the UK showed that 70 percent of 1,600 primary school teachers reported staying up all night to finish work at least once in the three months prior to the survey.
What we’re learning about memory consolidation may not trump students’ conviction that all-nighters are necessary at exam times, but it should give them some second thoughts.
Andrew Weil, M.D.
Pamela V. Thacher, “University Students and the “All Nighter”: Correlates and Patterns of Students’ Engagement in a Single Night of Total Sleep Deprivation.” Behavioral Sleep Medicine, January 10, 2008, DOI: 10.1080/15402000701796114
Paula R. Haynes, Bethany L. Christmann, Leslie C. Griffith. “A single pair of neurons links sleep to memory consolidation in Drosophila melanogaster.” eLife, January 7, 2015; 4 DOI: 10.7554/eLife.03868