Studying Into a Sleep Disorder

 The tale seems as old as time; college students head to the store to buy themselves coffee, energy drinks, or whatever else they may be able to use to prepare themselves for a long night of studying. Many wake up the next morning exhausted and devoid of motivation to get to class, but shrug off the previous night as merely a necessary part of university life. Some may even look back and joke about the amount of times they have spent the whole night studying. Most students assume that fighting sleep to cram in extra study time is a harmless venture; however, it may in fact be more serious than most people ever think to consider if it becomes habitual.

The issue of troubled sleep extends well beyond staying up late one night to prepare for an exam. Disturbances in sleep and poor sleep quality appear to be present in high percentages among college students, and this article will investigate the correlation between college life and sleep disorders/disturbances, as well as effects on academic and everyday performance.

 According to authors of a large study of sleep quality in adolescents and college students, this group is among the most sleep-deprived in America [1]. In their study of 1,125 students from an urban Midwest university, only 29.4% of students got the required 8 hours of sleep per night. A vast majority endorsed patterns of chronic restricted sleep, defined as sleeping less than 7 hours but more than 4 hours a night [1]. Along with the mere quantity of sleep being low, the study found that poor sleep quality was also prevalent in the population. Only 34.1% of students scored in the “good” range of the sleep quality test, and a staggering 75% of the students surveyed reported feeling dragged out, tired, or sleepy at least once per week [1].

This study is not alone in its findings, and in fact, data has shown that chronic issues with sleep are not solely an American phenomenon. Another study of university students in India by Kaur and Singh [2] looked into student sleep health through collecting data on Excessive Daytime Sleepiness (EDTS). EDTS occurs when an individual is having difficulty staying alert during the day due to the feeling of sleepiness. The data revealed that 44.5% of students at this university experienced EDTS [2]. The study also compared this result to data from students in various other disciplines, discovering similar findings across the board [2]. Both studies showed positive associations between stress as a result of academic workload and interrupted sleep quality [1 & 2].

Another similar study of students at an undergraduate university in Nigeria combined data about students’ sleep quality with the psychological distress they experienced from various environmental factors, like adjusting to a new routine, less supervision, pressure for academic success, and increased course load as a result of repeating classes with low marks. Researchers found that 253 out of the 520 students, or 50.1% of the population surveyed, were classified as poor sleepers according to the Pittsburgh Sleep Quality Index, a self-administered instrument consisting of 19 self-reported questions and 5 questions to be answered by a roommate or bed partner that examines several aspects of sleep dysfunction [3]. The study also found strong associations between certain stress factors, like a student’s year of study, and quality of sleep. The students were also examined for levels of anxiety, depression, and general psychological distress as an indicator of poor sleep, which researchers found to be strong predictors of decreased sleep quality [3].

These studies all converge on one theme: poor sleep is prevalent in university populations throughout the world, from Northern Africa to the American Midwest to Southeast Asia. Their findings suggest that insufficient sleep is especially detrimental for this demographic, as it might be normalized to a dangerous extent. In a conversation with a University of Michigan student, a doctor found that the student’s composite score was a 15 out of 24 on the Epworth Sleepiness Scale, which is in the range of patients with narcolepsy [4]. This scale uses a series of questions to determine the severity of daytime sleepiness in an individual [5]. In spite of serious health and academic risks, many students insist on staying awake through the night to accomplish a goal or make ends meet [4]. The doctor observed that this sacrifice of sleep had shifted students’ perception of a quality night’s rest to that of a luxury rather than a necessity, which may be another contributing factor for the prevalence of poor sleep in university populations [4].

The presented data continuously indicates that obtaining proper sleep is a major issue in college populations. The consequences of this extreme sleepiness, like reduced reaction times, impaired immune function, and compromised memory and learning, could become very harmful if this number persists in wider populations [4]. This concerning pattern begs the question, what effect does poor sleep quality and quantity have on a person, and perhaps more pointedly, how does it affect the brain?

Sleep deprivation has been shown to produce psychomotor impairments that are similar to those caused by alcohol consumption at or above the legal limit [6]. Experiments on the effects of motor impairments during simulated driving performances found that sleep deprived populations experienced difficulties in driving equivalent to a blood alcohol content of 0.07%, a value just under 0.08%, the legal driving limit and point of being considered legally intoxicated  [6 & 7]. Chronically poor sleep has also been shown to produce issues with prefrontal cortex-related cognitive performance in areas such as working memory, speed of cognitive output, and attention, as well as having adverse effects on tasks that require multitasking and flexible thinking [6]. 

Further studies on sleep deprivation in college students showed significant decrease in performance on cognitive tasks designed to assess inference, recognition of assumptions, and deduction skills [8]. The study also exposed an interesting phenomenon in which sleep deprived students reported higher estimates of their own performance and expressed greater amounts of effort expended on the required tasks [8]. Other studies of children tested for cognitive performance after poor sleep, and found difficulty in learning new abstract concepts, along with impaired performance in verbal fluency and flexibility [8]. 

The damages caused by ongoing sleep deprivation do not stop there. Findings from rodent studies suggest that sleep deprivation can substantially decrease the ability of scientists to induce long-term potentiation (LTP) in the hippocampus, a part of the brain associated with memory [9]. Notably, LTP is a cellular plasticity mechanism that is thought to underlie learning and memory. Sleep loss has also been shown to reduce production of new neurons and neural connections, further inhibiting one’s ability to create and store new memories [9]. Sleep deprivation affects the transmission of chemical signals in the brain, altering the dopamine-reward system in such a way that impairs the brain’s ability to decipher whether certain rewarding stimuli are of high or low value [9]. This can lead to higher levels of risk-taking and a decreased ability to weigh the importance of immediate or longer-term rewards [9].

Much of the focus thus far has been on the detrimental effects of poor sleep, but it is also important to discuss why sleep is important and how it can benefit the body. During sleep, the brain’s glymphatic system becomes active; this acts as a mechanism to clear out toxic products of neuronal activity, particularly excess neurotransmitters and other common proteins that are associated with neurodegenerative processes [10]. Sleep also provides for the overall health of neurons. This is particularly seen in the hippocampus, which allows this region to conduct neurogenesis. Neurogenesis refers to the development of new neurons for memory consolidation [10]. Increased amount of time spent in the Rapid Eye Movement, or “REM,” cycle of sleep, has also been shown to elicit higher levels of subjective post-sleep happiness upon waking up compared to those with less time spent in this stage [10]. Studies on the mechanisms of this process suggest that the brain is being primed for emotional processing of memories when in this state, indicating the importance of REM in both emotional state and memory consolidation [10]. Sleep benefits other regions of the body as well; activity of the immune system increases with circadian rhythm variation, and several studies have found that it functions more effectively in response to better sleep [10]. This can be seen in immune system memory, as individuals with restricted sleep demonstrate a significant reduction in antibodies levels in response to vaccination [10].

Obtaining sufficient sleep also works to prevent much of what was mentioned previously in this article. Prioritizing sleep and trying to get both adequate sleep quality and quantity helps to protect against EDTS. Adequate sleep can also be extremely helpful in improving levels of anxiety, depression, and stress. Furthermore, obtaining the appropriate amount of sleep can be beneficial in improving cognitive functioning, working memory, consolidation of long-term memory, and overall academic performance. Obtaining sufficient sleep can be seen as a measure taken to improve overall quality of life for anyone suffering from the effects of chronically restricted sleep.

The issue of insufficient sleep is certainly a widespread problem for young adults, as observed in university populations worldwide. The research outlined here provides evidence that disturbances in sleep, and poor sleep quality, are indeed present in high percentages among college students. This deep-rooted issue in this demographic has been found to profoundly negatively affect everyday life and academic performance. This is an issue greatly in need of attention at both an individual and systemic level, beginning with universities offering support and resources to struggling students, including extension of cognitive behavioral therapy for sleep related issues, as well as other offerings of psychological interventions that have been shown to be effective for a population vulnerable to sleep disorders and other psychological illnesses [11]. 

References:

1. 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(2), 124–132. https://doi.org/10.1016/j.jadohealth.2009.06.016 

2. Kaur, G., & Singh, A. (2017). Excessive daytime sleepiness and its pattern among Indian College students. Sleep Medicine, 29, 23–28. https://doi.org/10.1016/j.sleep.2016.08.020 

3. Seun-Fadipe, C. T., & Mosaku, K. S. (2017). Sleep quality and psychological distress among undergraduate students of a Nigerian University. Sleep Health, 3(3), 190–194. https://doi.org/10.1016/j.sleh.2017.02.004 

4. Hershner, S. (2015). Is sleep a luxury that college students cannot afford? Sleep Health, 1(1), 13–14. https://doi.org/10.1016/j.sleh.2014.12.006 

5. C. Zhang, L.J. Epstein, Screening and Case Finding for Obstructive Sleep Apnea, Editor(s): Clete A. Kushida, Encyclopedia of Sleep, Academic Press, 2013, Pages 449-453, ISBN 9780123786111, https://doi.org/10.1016/B978-0-12-378610-4.00350-8.

6. Durmer, J. S., & Dinges, D. F. (2005). Neurocognitive consequences of sleep deprivation. Seminars in Neurology, 25(01), 117–129. https://doi.org/10.1055/s-2005-867080 

7. MedlinePlus, I. (2020, December 3). Blood alcohol level: Medlineplus medical test. MedlinePlus. Retrieved November 14, 2021, from https://medlineplus.gov/lab-tests/blood-alcohol-level/. 

8. Curcio, G., Ferrara, M., & De Gennaro, L. (2006). Sleep loss, learning capacity and academic performance. Sleep Medicine Reviews, 10(5), 323–337. https://doi.org/10.1016/j.smrv.2005.11.001 

9. Krause, A. J., Simon, E. B., Mander, B. A., Greer, S. M., Saletin, J. M., Goldstein-Piekarski, A. N., & Walker, M. P. (2017). The sleep-deprived human brain. Nature Reviews Neuroscience, 18(7), 404–418. https://doi.org/10.1038/nrn.2017.55 

10. Schneider, L. (2020). Neurobiology and neuroprotective benefits of sleep. CONTINUUM: Lifelong Learning in Neurology, 26(4), 848–870. https://doi.org/10.1212/con.0000000000000878 

11. Saruhanjan, K, Zarski, A-C, Bauer, T, et al. Psychological interventions to improve sleep in college students: A meta-analysis of randomized controlled trials. J Sleep Res. 2021; 30:e13097. https://doi.org/10.1111/jsr.13097