by Laila Volpe, SRI International and Incoming Doctoral Student, University of Washington
When faced with an overwhelming amount of work, students often feel as if there aren’t enough hours in the day. To compensate, many choose to stay up later or wake up earlier, with some even pulling “all-nighters.” One study on sleep patterns in college students found that 20% reported staying awake all night at least once in the prior month, and 35% reported staying up until 3 a.m. at least once a week (Lund et al., 2010). While losing sleep in favor of studying may seem appealing at first, it can actually have an adverse effect on academic performance.
Sleep is thought to play a key role in memory consolidation. Though neurobiologists debate the methods by which sleep achieves these ends, rapid-eye movement (REM) and slow-wave sleep (SWS) both appear to facilitate information processing and memory storage. SWS involves slow, high-amplitude brain waves, and it tends to be more intense during the first few hours of the night. REM periods are categorized by darting eyes and low muscle movement and are typically observed to be longer during the last few hours of sleep. Research suggests that SWS facilitates declarative memory, for example factual information, while REM is hypothesized to promote other forms of memory like visual imagery (Rasch & Born, 2013). Therefore, cutting down on sleep can inadvertently prevent the memory consolidation processes from both SWS and REM, thus making it more difficult to remember material learned the day before.
Sleep deprivation has been shown to reduce memory retention while increased sleep is linked to better information recall. In one study by Schönauer and colleagues (2014), participants learned material like words, objects, and numbers, then received different amounts of sleep and were tested on their memory of that material once they woke. Those who napped for just two hours performed significantly better than those who did not (Schönauer et al., 2014). Similarly, another study found that sleep was the strongest predictor of exam scores for medical students, indicating that better sleep is associated with better academic performance (Genzel et al., 2013).
Stress and academic performance are strongly correlated as well. People who report higher stress tend to have lower grades (Almojali et al., 2017). These results could either suggest that higher stress affects grades or that people with lower grades are more stressed. Though we cannot definitively point to the directionality of this relationship, we do know that poorer sleep quality is associated with higher stress. In fact, sleep deprivation is shown to increase cortisol, the stress hormone, significantly compared to normal sleep patterns in the same participants (Wright et al., 2015). Because poor sleep increases stress, which in turn can impact grades, it is possible that stress acts as a mediator between low sleep quality and poorer academic performance.
Several studies have demonstrated that lack of sleep is significantly related to stress, and both are associated with worse academic performance. However, even a two-hour nap can have a significant positive effect. Therefore, the next time that you need to prepare for a test or presentation, prioritize sleep over studying. There are a few methods that you can try to improve sleep quality and quantity. Common strategies include reducing media use, especially before bed (Hale et al., 2017), getting regular exercise (Hartescu et al., 2015), and reducing alcohol use, which inhibits sleep quality (Colrain et al., 2018). It would be worth spending some time researching options that work well for you and implementing them as regularly as you can. With a full eight hours, you may find that you remember more than you thought you would! ________________________________________________________________
References
Almojali, A. I., Almalki, S. A., Alothman, A. S., Masuadi, E. M., & Alaqeel, M. K. (2017). The prevalence and association of stress with sleep quality among medical students. Journal of Epidemiology and Global Health, 7(3), 169-174. https://dx.doi.org/10.1016%2Fj.jegh.2017.04.005
Colrain, I. M., Nicholas, C. L., & Baker, F. C. (2018). Alcohol and the Sleeping Brain. Handbook of Clinical Neurology, 125, 415-431. https://dx.doi.org/10.1016%2FB978-0-444-62619-6.00024-0
Genzel, L., Ahrberg, K., Roselli, C., Niedermaier, S., Steiger, A., Dresler, M., & Roenneberg, T. (2013). Sleep timing is more important than sleep length or quality for medical school performance. Chronobiology International, 30(6), 766-771. https://dx.doi.org/10.3109/07420528.2012.763132
Hale, L., Kirschen, G. W., LeBourgeois, M. K., Gradisar, M., Garrison, M. M., Montgomery-Downs, H., Kirschen, H., McHale, S. M., Chang, A., & Buxton, O. M. (2018). Youth Screen Media Habits and Sleep: Sleep-Friendly Screen Behavior Recommendations for Clinicians, Educators, and Parents. Child and Adolescent Psychiatry Clinics of North America, 27(2), 229-245. https://dx.doi.org/10.1016%2Fj.chc.2017.11.014
Hartescu, I., Morgan, K., & Stevinson, C.D. (2015). Increased physical activity improves sleep and mood outcomes in inactive people with insomnia: a randomized controlled trial. Journal of Sleep Research, 24(5), 526-534. https://doi.org/10.1111/jsr.12297
Lund, H. G., Reider, B. D., Whiting, A. B., & Prichard, J. R. (2010). Sleep Patterns and Predictors of Disturbed Sleep in a Large Population of College Students. Journal of Adolescent Health, 46, 124-132. https://doi.org/10.1016/j.jadohealth.2009.06.016
Rasch, B., & Born, J. (2013). About Sleep’s Role in Memory. Physiological Reviews, 93(2), 681-766.
https://dx.doi.org/10.1152%2Fphysrev.00032.2012
Schönauer, M., Pawlizki, A., Köck, C., & Gais, S. (2014). Exploring the Effect of Sleep and Reduced Interference on Different Forms of Declarative Memory. Sleep, 37(12), 1995-2007. https://dx.doi.org/10.5665%2Fsleep.4258
Wright, K. P., Drake, A. L., Frey, D. J., Fleshner, M., Desouza, C. A., Gronfier, C., & Czeisler, C. A. (2015). Influence of Sleep Deprivation and Circadian Misalignment on Cortisol, Inflammatory Markers, and Cytokine Balance. Brain, Behavior, and Immunity, 47, 24-34. https://dx.doi.org/10.1016%2Fj.bbi.2015.01.004
Disclaimer: The views and opinions expressed in this newsletter are those of the authors alone and do not necessarily reflect the official policy or position of the Psychological Clinical Science Accreditation System (PCSAS).