
An official website of the United States government
The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
- Publications
- Account settings
- My Bibliography
- Collections
- Citation manager

Save citation to file
Email citation, add to collections.
- Create a new collection
- Add to an existing collection
Add to My Bibliography
Your saved search, create a file for external citation management software, your rss feed.
- Search in PubMed
- Search in NLM Catalog
- Add to Search
Impact factor rankings for sleep research journals between 2005 and 2018
Affiliations.
- 1 CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, The University of Sydney, Sydney, NSW, Australia.
- 2 Faculty of Medicine and Health Sciences, The University of Sydney, Sydney, NSW, Australia.
- 3 School of Psychology, The University of Sydney, Sydney, NSW, Australia.
- PMID: 32233003
- DOI: 10.1111/jsr.13015
Impact factors and ranking lists of research journals are very often used to judge our career achievements and progression by employers and granting bodies. However, a comprehensive list for the interdisciplinary field of sleep research does not currently exist because our journals tend to be placed into discipline-specific lists that do not cope well with our historic interdisciplinarity, which embraces many core disciplines. We aimed to build a ranking list specifically for sleep research journals based on the journal impact factor and the google scholar H 5 indices. We then searched for all sleep journals given an impact factor by Thomson Reuters from 2005 to 2018 and all journals given a current H 5 index by Google Scholar. We provide a ranking list specifically for sleep journals that might be useful for researchers to cite when providing context in their applications for employment, promotion and funding.
Keywords: careers; jobs; meta-epidemiology.
© 2020 European Sleep Research Society.
Similar articles
- [Rating and ranking of medical journals: a randomised controlled evaluation of impact factor and number of listed journals]. Göbel U, Niem V. Göbel U, et al. Klin Padiatr. 2012 Jan;224(1):43-50. doi: 10.1055/s-0031-1299726. Epub 2012 Feb 8. Klin Padiatr. 2012. PMID: 22318379 German.
- Current biomedical scientific impact (2013) of institutions, academic journals and researchers in the Republic of Macedonia. Spiroski M. Spiroski M. Pril (Makedon Akad Nauk Umet Odd Med Nauki). 2014;35(3):67-80. doi: 10.1515/prilozi-2015-0010. Pril (Makedon Akad Nauk Umet Odd Med Nauki). 2014. PMID: 25711224
- Comparison of Impact Factor, Eigenfactor Metrics, and SCImago Journal Rank Indicator and h-index for Neurosurgical and Spinal Surgical Journals. Yuen J. Yuen J. World Neurosurg. 2018 Nov;119:e328-e337. doi: 10.1016/j.wneu.2018.07.144. Epub 2018 Jul 25. World Neurosurg. 2018. PMID: 30055360
- A technique to identify core journals for neurosurgery using citation scatter analysis and the Bradford distribution across neurosurgery journals. Madhugiri VS, Ambekar S, Strom SF, Nanda A. Madhugiri VS, et al. J Neurosurg. 2013 Nov;119(5):1274-87. doi: 10.3171/2013.8.JNS122379. Epub 2013 Sep 13. J Neurosurg. 2013. PMID: 24032696 Review.
- Conflict of interest policies and disclosure requirements in neurosurgical journals. de Lotbiniere-Bassett MP, Riva-Cambrin J, McDonald PJ. de Lotbiniere-Bassett MP, et al. J Neurosurg. 2018 Aug 17;131(1):264-270. doi: 10.3171/2018.4.JNS172751. J Neurosurg. 2018. PMID: 30117775 Review.
- A comparison of scientometric data and publication policies of ophthalmology journals. Ay IE, Tazegul G, Duranoğlu Y. Ay IE, et al. Indian J Ophthalmol. 2022 May;70(5):1801-1807. doi: 10.4103/ijo.IJO_2720_21. Indian J Ophthalmol. 2022. PMID: 35502077 Free PMC article.
- Scientometric Data and Open Access Publication Policies of Clinical Allergy and Immunology Journals. Tazegul G, Emre E. Tazegul G, et al. Cureus. 2021 Feb 26;13(2):e13564. doi: 10.7759/cureus.13564. Cureus. 2021. PMID: 33815978 Free PMC article.
- Publishing in Hematology Journals: A Scientometric and Economic Evaluation. Tazegul G, Atas U, Ulas T, Toptas T, Salim O. Tazegul G, et al. Cureus. 2020 Dec 14;12(12):e12069. doi: 10.7759/cureus.12069. Cureus. 2020. PMID: 33489487 Free PMC article.
- Alberts, B. (2013). Impact factor distortions. Science, 340(6134), 787.
- Garfield, E. (1963). Citation indexes in sociological and historical research. American Documentation, 14(4), 289-291.
- Gasparyan, A. Y., Yessirkepov, M., Duisenova, A., Trukhachev, V. I., Kostyukova, E. I., & Kitas, G. D. (2018). Researcher and author impact metrics: Variety, value, and context. Journal of Korean Medical Science, 33(18), e139.
- Harzing, A., & van der Wal, R. (2008). Google Scholar as a new source for citation analysis? Ethics in Science and Environmental Politics, 8(1), 61-73. https://doi.org/10.3354/esep00076
- Hirsch, J. E. (2005). An index to quantify an individual's scientific research output. Proceedings of the National Academy of Sciences of the United States of America, 102(46), 16569.
Publication types
- Search in MeSH
LinkOut - more resources
Full text sources.
- Ovid Technologies, Inc.

- Citation Manager
NCBI Literature Resources
MeSH PMC Bookshelf Disclaimer
The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). Unauthorized use of these marks is strictly prohibited.

An official website of the United States government
Here’s how you know
Official websites use .gov A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS A lock ( A locked padlock ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
- Health Topics A-Z
- Clinical Trials
- Publications and Resources
- Health Education and Awareness
- Information & Resources on COVID-19
- Blood Disorders and Blood Safety
- Sleep Science and Sleep Disorders
- Lung Diseases
- Health Disparities and Inequities
- Heart and Vascular Diseases
- Precision Medicine Activities
- Obesity, Nutrition, and Physical Activity
- Population and Epidemiology Studies
- Women’s Health
- All Science A-Z
- Grants and Training Home
- Policies and Guidelines
- Funding Opportunities and Contacts
- Training and Career Development
- Email Alerts
- NHLBI in the Press
- Research Features
- Past Events
- Upcoming Events
- Mission and Strategic Vision
- Divisions, Offices and Centers
- Advisory Committees
- Budget and Legislative Information
- Jobs and Working at the NHLBI
- Contact and FAQs
- NIH Sleep Research Plan
- About the NHLBI
- < Back To Division of Lung Diseases
- National Center on Sleep Disorders Research
The National Center on Sleep Disorders Research (NCSDR) supports research, technology innovation, training, health education, and other activities that advance scientific knowledge of sleep disorders and circadian biology, and that promote sleep health. The NCSDR also coordinates sleep and circadian biology research throughout the National Institutes of Health (NIH) and other Federal agencies. Located within the National Heart, Lung, and Blood Institute, the NCSDR was established by Congress as part of the NIH Revitalization Act of 1993 (42 USC Sec. 285b-7) .
Under that act, the Sleep Disorders Research Advisory Board (SDRAB) makes recommendations and assists with the development of a comprehensive NIH plan that identifies sleep and circadian research priorities. Read the 2021 NIH Sleep Research Plan .
NIH funds sleep and circadian research through investigator-initiated and Institute-initiated programs.
- Learn more about funding opportunities for research on sleep and the circadian biology of sleep disorders.
- Read about how the NHLBI's Sleep Science and Sleep Disorders research is making a difference.
- Sign up for updates from the NCSDR and the NHLBI through the NIH Listserv .
Related Scientific Focus Areas
- Related News and Events
Mission - National Center on Sleep Disorders Research
The National Center on Sleep Disorders Research (NCSDR) promotes sleep and circadian scientific advances, from laboratory research to clinical practice, to improve scientific knowledge, transform health care, and advance public health and safety and the well-being of the nation.

The NCSDR works toward achieving its mission in the following ways:
- Advancing scientific knowledge in essential research areas including chronobiology, neurophysiology, gene expression, epigenetics, and proteostatis.
- Transforming health care using chronomedicine, clinical interventions, and patient-centered strategies, including measuring epidemiological risks and risk stratification.
- Advancing well-being by considering the impact of social determinants of health, health disparities, and individual and community-based interventions on health outcomes.
- Improving public health and safety by promoting sleep health awareness and related risk prevention at worksites, schools, housing and in transportation through technologies such as solid-state lighting.
One enduring strategy the NCSDR uses to achieve this mission is by fostering a strong and diverse workforce.
What We Do - National Center on Sleep Disorders Research
Chronobiology and Ventilatory Control
The chronobiology and ventilatory control portfolio supports basic and clinical research that explores how circadian science applies to the development, diagnosis, and treatment of heart, lung, blood disorders. The portfolio also includes research that describes neural and peripheral mechanisms of breathing control, chemoreception, and the integration of breathing with other functions (e.g., coughing and swallowing). Research in this portfolio is performed using a range of approaches, from studying genes (genomics) to conducting clinical trials. The research addresses current public health concerns, such as the role of sleep, circadian regulation, and ventilatory control in maternal morbidity and mortality, opioid use disorder, and obesity.
Contact: Aaron D. Laposky, Ph.D., [email protected]
Neurobiology of Sleep
The sleep and neurobiology portfolio supports studies on the neurobiological mechanisms of sleep and its disorders, as well as analyses of the diverse influences on these processes. Investigations include explorations of the roles of identified physiological and pathological mechanisms in sleep and the use of genetic and genomic approaches to uncover novel factors affecting sleep. The research also explores the connections between sleep disorders, health disparities, and social determinants of health. This portfolio includes computational models, animal models, and clinical investigations of the mechanisms of sleep disorders and their consequences. It also includes a variety of training grant mechanisms , particularly institutional training grants (T32) focused on sleep and circadian rhythms.
Contact: Lawrence Baizer, Ph.D., [email protected]
Prevention and Sleep Health
The prevention and sleep health portfolio supports research focused on the relationship between healthy sleep and physical health and well-being, and chronic disease prevention. Studies include investigations into modifying sleep-wake patterns and sleep behaviors to improve health across the life span, and social determinants that contribute to sleep health disparities and impact special populations. This portfolio also includes training and career development grant mechanisms, and Small Business Innovation Research and Small Business Technology Transfer (SBIR/STTR) grant mechanisms for innovative research to develop novel devices and interventions that improve healthy sleep and adherence to treatment.
Contact: Shilpy Dixit, Ph.D., [email protected]
Sleep Disorders Medicine
The sleep disorders medicine portfolio supports research on the genetic predisposition, risk factors, pathogenesis, epidemiology, diagnosis, and treatment of sleep and circadian rhythm sleep-wake disorders. This includes research examining the role of sleep in inflammation, cardiometabolic disorders, vascular contributions to cognitive impairment and dementia, and people living with Down syndrome as part of the NIH INCLUDE program. Additionally, this program supports studies using big data analytics, artificial intelligence, and clinical trials to explore sleep and circadian disorders.
Contact: Alfonso Alfini, Ph.D., [email protected]
NIH and Inter-Agency Coordination - National Center on Sleep Disorders Research
Sleep disorders, circadian biology, and sleep health relate to a multitude of biological systems, health conditions, and medical disciplines. That is why a coordinated and collaborative approach must be used to successfully advance sleep and circadian science, foster technology transfer, expand training, transform health care, and increase dissemination of health information to advance well-being and improve public health and safety.
The NCSDR serves as the point-of-contact for researchers, professional societies, non-governmental stakeholders (public, private, and nonprofit groups), and other Federal agencies interested in NIH sleep research activities.
The NCSDR director serves as the Executive Secretary of the SDRAB , an Advisory Board composed of Members and Ex Officio Members and led by a member-elected chairperson.
The NCSDR leads the NIH-wide Sleep Research Coordinating Committee , a forum to discuss and consider potential opportunities for programmatic coordination of biological and circadian rhythms research and other sleep-related research, training, and health information dissemination.
The NCSDR fosters the coordination of sleep and circadian research among other Federal agencies, including:
- Bureau of the Census
- Centers for Disease Control and Prevention
- National Aeronautics and Space Administration (NASA)
- National Highway Traffic Safety Administration/U.S. Department of Transportation
- U.S. Department of Labor
- U.S. Department of Defense
- U.S. Department of Energy
- U.S. Department of Housing and Urban Development
- U.S. Department of Veterans Affairs
The NCSDR director and staff meet regularly with sleep and circadian researchers, professional societies, and other stakeholders to gather feedback and offer updates.
Healthcare Provider Resources - National Center on Sleep Disorders Research
NCSDR works to turn research findings into health information that benefits the public. It does this, in part, by educating healthcare professionals about the results of sleep disorders research and offering resources they can share with their patients and families.
The NHLBI Online Catalog lists all NHLBI publications and resources for healthcare professionals, including summaries of the latest sleep science and clinical care best practices. It also lists educational materials that help answer patients’ questions about sleep and sleep disorders.
Patient and Public Education Resources - National Center on Sleep Disorders Research
The NHLBI website features health information on sleep-related health topics for patients, caregivers, and the public. To find links to topics such as insomnia, sleep deprivation and deficiency, sleep apnea, narcolepsy, and sleep studies, go to the Sleep Health webpage and click on the Health Topics icon. You can also find there a link to Your Guide to Healthy Sleep , as well as information about participating in a clinical trial.
Division Leadership
Marishka K. Brown, Ph.D.
Director, national center on sleep disorders research, related news.

RELATED EVENT

Future Vacancies
Health scientist administrators – division of lung diseases.
- Airway Biology and Disease Branch
- Lung Biology and Disease Branch
Health Scientist Administrators (program officers) advise the Institute on future scientific directions that encourage research in critical areas, develop targeted...
Contact National Center on Sleep Disorders Research
National Center on Sleep Disorders Research, NHLBI, NIH 6701 Rockledge Drive Bethesda , MD 20892 United States
National Center on Sleep Disorders Research [email protected]
Sign up for public updates from the NCSDR
Sign up for biomedical research updates from NCSDR

Effect of Inadequate Sleep on Frequent Mental Distress
ORIGINAL RESEARCH — Volume 18 — June 17, 2021
Amanda Blackwelder, MPH 1 ; Mikhail Hoskins, MPH 1 ; Larissa Huber, PhD 1 ( View author affiliations )
Suggested citation for this article: Blackwelder A, Hoskins M, Huber L. Effect of Inadequate Sleep on Frequent Mental Distress. Prev Chronic Dis 2021;18:200573. DOI: http://dx.doi.org/10.5888/pcd18.200573 external icon .
PEER REVIEWED
Introduction
Acknowledgments, author information.
What is already known on this topic?
One-third of US adults report that they sleep less than the recommended amount, and approximately 20% have received a diagnosis of a mental illness. The link between inadequate sleep and mental distress has been viewed historically as a symptom–disease association with sleep inadequacies deriving from preexisting mental distress.
What is added by this report?
We examined the association between inadequate sleep and frequent mental distress in a diverse, population-based sample of adults aged 18 to 65.
What are the implications for public health practice?
By identifying the correlation between inadequate sleep and frequent mental distress we can better understand this relationship as a risk factor instead of a symptom–disease relationship.
One-third of US adults report sleeping less than the recommended amount, and approximately 20% live with a mental illness. The objective of our study was to examine the association between inadequate sleep and frequent mental distress in a population-based sample of US adults.
We conducted a cross-sectional study by using 2018 Behavioral Risk Factor Surveillance System (BRFSS) data that included 273,695 US adults aged 18 to 64. Inadequate sleep was defined as 6 hours or less in a given night, and frequent mental distress was defined as self-reporting 14 days of mental health status as “not good” within the last month. We used weighted logistic regression to calculate odds ratios (ORs) and 95% CIs.
Thirteen percent of study participants experienced inadequate sleep, and 14.1% experienced frequent mental distress. Participants who averaged 6 hours or less of sleep per night were about 2.5 times more likely to have frequent mental distress when controlling for confounders (OR, 2.52; 95% CI, 2.32–2.73) than those who slept more than 6 hours.
Inadequate sleep was associated with significantly increased odds of frequent mental distress. Our findings suggest that further research is necessary to evaluate the temporal relationship between inadequate sleep and frequent mental distress.
Poor mental health is common in the US. Nearly 1 in 5 US adults live with mental illness (1). Furthermore, an estimated 50% of all Americans will be diagnosed with a mental illness or disorder at some point in their life (1,2). Mental health illness includes many different conditions and symptoms, such as anxiety, depression, stress, and other psychological illnesses. Moderate and severe mental disorders that need psychological treatment require regular visits to a health care provider, thus lowering workplace productivity (3). Furthermore, depression, schizophrenia, and bipolar disorder are risk factors for coronary heart disease, hypertension, diabetes, dyslipidemia, metabolic syndrome, obesity, stroke, and substance abuse disorders (3,4). Depression and anxiety alone cost over $1 trillion annually for medications, outpatient and primary care visits, and inpatient care (3,4).
The Centers for Disease Control and Prevention (CDC) and the American Academy of Sleep Medicine emphasize the importance of an adequate night’s sleep, which is defined as 7 or more hours per night with no upper limit (5,6). Anything less than this amount may lead to the development of various chronic diseases. More than one-third of the US population does not get adequate sleep (5). The people that most often get inadequate sleep are Native Hawaiian/Pacific Islander people, non-Hispanic Black people, and multiracial people (6). Those who most often get adequate sleep are married people and people with a college degree or more.
Studies have demonstrated an association between inadequate sleep and frequent mental distress (7,8), and sleep deprivation causes substantial negative health outcomes (4). The link between inadequate sleep and frequent mental distress has been viewed historically as a symptom–disease association with sleep inadequacies deriving from preexisting mental distress (9). However, at least 1 study researched the opposite hypothesis, evaluating frequent mental distress leading to a lack of sleep (10). These studies found that in certain populations, risk for inadequate sleep is increased if a person is experiencing depression or anxiety. Most current research on the potential association between inadequate sleep and mental distress focuses on a specifically defined group, such as college students, nurses, or people with diagnosed sleep disorders (9,11,12). Furthermore, current research focuses primarily on diagnosed mental health disorders (4,8). The purpose of our study was to examine the association between inadequate sleep and frequent mental distress in a diverse, population-based sample of adults aged 18 to 64.
We used 2018 Behavioral Risk Factor Surveillance System (BRFSS) data to analyze the association between sleep and self-reported mental distress. BRFSS is a cross-sectional survey that uses a standardized questionnaire to collect prevalence data regarding risk behaviors and preventive behavioral health practices among adult US residents (13). Participants self-report information during telephone interviews conducted by trained personnel. Interviewers make calls for interviews 7 days a week during the day and evening (14). BRFSS raw data, which are collected during the survey, are submitted to CDC each year for processing and are made available to researchers the following calendar year through annual reports available on the CDC website (https://www.cdc.gov/brfss/index.html). BRFSS is conducted in all 50 states, the District of Columbia, and 3 US territories. Noninstitutionalized adults aged 18 or older are eligible to complete the BRFSS survey (15). Over 400,000 adults are interviewed each year. The land line response rate for BRFSS is 53.3%, and the cellular telephone response rate is 43.3% (16). A total of 437,436 people completed the BRFSS survey in 2018. After excluding those participants who were not aged 18 to 64 (n = 160,115) and those who did not have information on frequent mental distress (n = 3,626), 273,695 survey participants remained for analysis.
The survey question used to identify the exposure variable of interest reads, “On average, how many hours of sleep do you get in a 24-hour period?” Participants were asked to provide a value from 1 to 24 hours. Sleep values were recorded as whole numbers, and values greater than 30 minutes were rounded up per BRFSS coding. Inadequate sleep was defined as 6 hours or less of sleep in a given 24-hour period, which is 1 hour less than the minimum recommended number of hours of sleep for adults (5,17,18). We chose this definition of inadequate sleep because the rounding done by BRFSS personnel could have created situations where people who actually had inadequate sleep were classified as having the minimum recommended hours. Furthermore, previous studies also defined inadequate sleep as 6 hours or less per night (5,17). Thus, using this same definition allows for better comparison across studies.
The survey question selected to identify the outcome of interest, frequent mental distress, was “Now thinking about your mental health, which includes stress, depression, and problems with emotions, for how many days during the past 30 days was your mental health not good?” (13). The responses were recorded as the number of days (ie, 1–30 days). Frequent mental distress was considered present if 14 or more days were reported as mental health “not good” in the previous month. This definition was based on recommendations from previous studies on frequent mental distress (19) and guidance from the American Psychiatric Association on the necessary duration of symptoms to diagnose depression (20).
Potential confounders were selected on the basis of prior research and included age, race/ethnicity, sex, current smoking status, binge drinking, marital status, education, income, and loss of insurance (21–28). Study participants were asked the following question regarding alcohol consumption: “One drink is equivalent to a 12-ounce beer, a 5-ounce glass of wine, or a drink with one shot of liquor. During the past 30 days, on the days when you drank, about how many drinks did you drink on the average?” (13). We used this information to create a dichotomous binge drinking variable; in the past 30 days on the days when they drank, men who had 5 or more drinks and women who had 4 or more drinks were classified as binge drinkers (29). To assess current smoking, participants were asked, “Do you now smoke cigarettes every day, some days, or not at all?” Ultimately, this variable was dichotomized into people who smoked every day or some days and people who did not smoke at all.
A primary univariate analysis was performed to obtain frequencies and weighted percentages of the exposure, outcome, and potential confounders at the P < .20 level. We used logistic regression to assess the association between self-reported sleep and frequent mental distress and to identify other risk factors for frequent mental distress. Multivariate logistic regression was used to obtain the odds ratio for the association between inadequate sleep and frequent mental distress while adjusting for potential confounders. A backward elimination approach was used to retain confounders at the P < .05 level. Ultimately, age, marital status, income, smoking status, and education level were identified as confounders. Because of the complex sampling design used by BRFSS, weighted analyses were performed using Stata version 15.1 (StataCorp LLC).
Most study participants were non-Hispanic White (59.1%), female (50.2%), married (49.3%), and had at least a high school diploma (87.4%) ( Table 1 ). Most participants reported that they had adequate nightly sleep (87.0%), and 14.1% experienced frequent mental distress (≥14 d/mo). Mean hours of sleep per 24-hour period were similar across age groups (18–34: 6.9 h; 35–49: 6.8 h; 50–64: 6.9 h).
People with inadequate sleep had nearly a threefold increased odds of frequent mental distress compared with those who had adequate sleep, and this finding was significant (OR, 2.67; 95% CI, 2.51–2.84) ( Table 2 ). Participants who were divorced/separated/widowed had twice the odds of frequent mental distress compared with study participants who were married (OR, 2.14; 95% CI, 2.01–2.29). There was a dose–response association between education level and frequent mental distress. As education levels decreased, the odds of frequent mental distress increased (high school diploma, GED, associate degree, or no university degree: OR, 2.06; 95% CI, 1.95–2.18; no high school diploma: OR, 3.35; 95% CI, 3.06–3.67).
After adjustment for age, marital status, income, smoking status, and education level, the inadequate sleep–frequent mental distress association was attenuated but remained significant. Participants with inadequate sleep had nearly 2.5 times increased odds of frequent mental distress compared with those with adequate sleep (OR, 2.52; 95% CI, 2.32–2.73; P < .001).
In our population-based study of US adults, inadequate sleep was associated with significantly increased odds of mental distress after controlling for confounding variables. Our findings align with previous research with the caveat that prior research has often looked at sleep as the outcome (8). Because our study used a large sample of adults and excluded only those who did not respond to qualifying questions, our results further confirm a potential association between inadequate sleep and mental health in a broader population.
Our study findings suggest an association between inadequate sleep and frequent mental distress. Because BRFSS is a cross-sectional study design, determining the true temporal sequence is not possible. Previous research has not closely examined the association between inadequate sleep as a risk factor for frequent mental distress. However, inadequate sleep has been linked to poor biological measures, including hypertension, anemia, and dyslipidemia (7). Low amounts of sleep and the attributed chronic conditions could possibly have a negative impact on depressive symptoms (7).
Limitations to this study include the potential for nondifferential misclassification of both the exposure and outcome variables; failure to recall information or misunderstanding questions asked possibly resulted in inaccurate responses. Also, self-reporting of mental distress is subjective. People may differ in their self-reporting and interpretation of what is “not good” for mental health. Furthermore, the use of a telephone interview could possibly influence self-reporting of mental distress. However, research demonstrates that the reporting of mental health information does not differ between face-to-face interviews and telephone interviews (31,32). In some instances, telephone interviews reduced embarrassment to participants when discussing mental health. We used a cut point of 6 hours to determine inadequate sleep rather than 7 hours, which is the minimum recommended hours of sleep for adults. We reran our model using 7 hours as the cut point for inadequate sleep, and our findings were of similar magnitude and remained significant. Given our aforementioned concerns that the rounding done by BRFSS personnel as it relates to the sleep duration variable could have incorrectly classified participants, we ultimately decided to retain our 6-hour cut point. In addition, because this definition of inadequate sleep has been used by others, it allows for better comparison across studies (5,17). Regardless, any nondifferential misclassification in our study would likely bias the results toward the null. Because we used a secondary data source, we were limited to the questions asked in the BRFSS survey. Thus, confounding by variables not measured in the BRFSS was possible. Selection bias is possible given that the response rate for BRFSS was 53.3% for landline responses and 43.3% for cellular telephone responses (15). The extent to which participation in BRFSS would be related to inadequate sleep and frequent mental distress is unknown; however, BRFSS is widely considered to be a valid and reliable measure of mental health and health behaviors (33).
Our study had numerous strengths. Information bias is unlikely because of the use of trained interviewers and standardization of interview methods. The exposure question may capture sleep data with more precision because it asks how many hours the participant slept in a 24-hour period. Thus, naps are included in the reporting. In addition, the wording enables the sleeping habits of people who do not work traditional day-time jobs to be more accurately reported. Establishing hours slept in a 24-hour period is consistent with prior research, giving a continuity of comparison across studies (4,7,8). Finally, our study included all participants aged 18 to 64 and did not focus only on those with preexisting conditions or on populations at risk for inadequate sleep (4,8). Thus, given the large sample size and the complex sampling design used by BRFSS, our findings are likely generalizable to adults living in the US.
Because one-third of the US population is not attaining adequate sleep, our findings warrant further research to expand on the true association between inadequate sleep and frequent mental distress (5). Thorough clinical assessment of sleep by age and length and quality of sleep could strengthen the measurement of the exposure. More thorough follow-up questions related to mental distress, including clinical diagnoses, may allow for a clearer evaluation of the temporal sequence between inadequate sleep and mental distress.
No copyrighted material was used in this article.
Corresponding Author: Amanda Blackwelder, MPH, UNC Charlotte, Department of Public Health Sciences, Charlotte, NC 28223. Telephone: 704-687-8719. Email: [email protected] .
Author Affiliations: 1 University of North Carolina at Charlotte, Charlotte, North Carolina.
- National Institute of Mental Health. Mental illness. https://nimh.nih.gov/health/statistics/mental-illness.shtml. 2019. Accessed September 13, 2019.
- Centers for Disease Control and Prevention. Mental health. https://www.cdc.gov/mentalhealth/data_publications/index.htm. 2018. Accessed September 13, 2019.
- Chisholm D, Sweeny K, Sheehan P, Rasmussen B, Smit F, Cuijpers P, et al. Scaling-up treatment of depression and anxiety: a global return on investment analysis. Lancet Psychiatry 2016;3(5):415–24. CrossRef external icon PubMed external icon
- De Hert M, Dekker JM, Wood D, Kahl KG, Holt RIG, Möller H-J. Cardiovascular disease and diabetes in people with severe mental illness position statement from the European Psychiatric Association (EPA), supported by the European Association for the Study of Diabetes (EASD) and the European Society of Cardiology (ESC). Cambridge (GB): Cambridge University Press; 2009. CrossRef external icon
- American Academy of Sleep Medicine. Seven or more hours of sleep per night: a health necessity for adults. 2015. https://aasm.org/seven-or-more-hours-of-sleep-per-night-a-health-necessity-for-adults/. Accessed September 19, 2019.
- Centers for Disease Control and Prevention. 1 in 3 Adults don’t get enough sleep. 2016. https://www.cdc.gov/media/releases/2016/p0215-enough-sleep.html. Accessed September 19, 2019
- Peltzer K, Pengpid S. Self-reported sleep duration and its correlates with sociodemographics, health behaviours, poor mental health, and chronic conditions in rural persons 40 years and older in South Africa. Int J Environ Res Public Health 2018;15(7):E1357. CrossRef external icon PubMed external icon
- Wang S, Wu Y, Ungvari GS, Ng CH, Forester BP, Gatchel JR, et al. Sleep duration and its association with demographics, lifestyle factors, poor mental health and chronic diseases in older Chinese adults. Psychiatry Res 2017;257:212–8. CrossRef external icon PubMed external icon
- Hanson JA, Huecker MR. Sleep deprivation. 2019. https://www.ncbi.nlm.nih.gov/books/NBK547676/. Accessed September 13, 2019.
- Jackson CL; National Library of Medicine. Determinants of racial/ethnic disparities in disordered sleep and obesity. Sleep Health 2017;3(5):401–15. CrossRef external icon PubMed external icon
- Sleep and mental health. Once viewed only as symptoms, sleep problems may actually contribute to psychiatric disorders. Harvard Mental Health Letter 2009;26(1);1–3. http://search.ebscohost.com/login.aspx?direct=true&db=rzh&AN=105362927&site=ehost-live&scope=site. Accessed September 13, 2019.
- Grimes AR. Anxiety and sleep disorder comorbidity: affecting the college students’ performances. Fayetteville (AR): University of Arkansas, ProQuest Dissertations Publishing; 2012.
- Centers for Disease Control and Prevention. Behavioral Risk Factor Surveillance System. 2014. https://www.cdc.gov/brfss/about/index.htm. Accessed October 27, 2019.
- Centers for Disease Control and Prevention. The Behavioral Risk Factor Surveillance System: overview: BRFSS 2018. https://www.cdc.gov/brfss/annual_data/2018/pdf/overview-2018-508.pdf. Accessed October 27, 2019.
- Centers for Disease Control and Prevention. Behavioral Risk Factor Surveillance System. 2019. https://www.cdc.gov/chronicdisease/resources/publications/factsheets/brfss.htm?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fchronicdisease%2Fresources%2Fpublications%2Faag%2Fbrfss.htm. Accessed October 27, 2019.
- Centers for Disease Control and Prevention. BRFSS combined landline and cell phone weighted response rates by state, 2018. https://www.cdc.gov/brfss/annual_data/2018/pdf/2018-response-rates-table-508.pdf. Accessed September 19, 2019.
- Zochil M, Thorsteinsson E. Exploring poor sleep, mental health, and help‐seeking intention in university students. Aust J Psychol 2018;70(1):41–7. CrossRef external icon
- Centers for Disease Control and Prevention.LPPC 2018 Codebook Report: Behavioral Risk Factor Surveillance System.https://www.cdc.gov/brfss/annual_data/2018/pdf/codebook18_llcp-v2-508.pdf. Accessed November 24, 2019.
- Bruzelius E, Baum A. The mental health of Hispanic/Latino Americans following national immigration policy changes: United States, 2014–2018. Am J Public Health 2019;109(12):1786–8. CrossRef external icon PubMed external icon
- American Psychiatric Association. Diagnostic and statistical manual of mental disorders (DSM-5), Fifth edition. 2013. National Institute of Mental Health. (Data from 2013 National Survey on Drug Use and Health.) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777342/. Accessed September 22, 2019.
- Stephan Y, Sutin AR, Bayard S, Terracciano A. Subjective age and sleep in middle-aged and older adults. Psychol Health 2017;32(9):1140–51. CrossRef external icon PubMed external icon
- O’Connor GT, Lind BK, Lee ET, Nieto FJ, Redline S, Samet JM, et al. ; Sleep Heart Health Study Investigators. Variation in symptoms of sleep-disordered breathing with race and ethnicity: the Sleep Heart Health Study. Sleep 2003;26(1):74–9. https://www.ncbi.nlm.nih.gov/pubmed/12627736 PubMed external icon
- Maume DJ, Sebastian RA, Bardo AR. Gender, work-family responsibilities, and sleep. Gend Soc 2010;24(6):746–68. CrossRef external icon
- Hayley AC, Stough C, Downey LA. DSM-5 tobacco use disorder and sleep disturbance: findings from the National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III). Subst Use Misuse 2017;52(14):1859–70. CrossRef external icon PubMed external icon
- Meadows R, Arber S. Marital status, relationship distress, and self-rated health: what role for “sleep problems”? J Health Soc Behav 2015;56(3):341–55. CrossRef external icon PubMed external icon
- Patel NP, Grandner MA, Xie D, Branas CC, Gooneratne N. “Sleep disparity” in the population: poor sleep quality is strongly associated with poverty and ethnicity. BMC Public Health 2010;10(1):475. CrossRef external icon PubMed external icon
- Hirshkowitz M, Whiton K, Albert SM, Alessi C, Bruni O, DonCarlos L, et al. National Sleep Foundation’s sleep time duration recommendations: methodology and results summary. Sleep Health 2015;1(1):40–3. CrossRef external icon PubMed external icon
- Centers for Disease Control and Prevention. Alcohol and public health: binge drinking. 2019. https://www.cdc.gov/alcohol/fact-sheets/binge-drinking.htm. Accessed November 16, 2020.
- Rohde P, Lewinsohn PM, Seeley JR. Comparability of telephone and face-to-face interviews in assessing axis I and II disorders. Am J Psychiatry 1997;154(11):1593–8. CrossRef external icon PubMed external icon
- Fenig S, Levav I, Kohn R, Yelin N. Telephone vs face-to-face interviewing in a community psychiatric survey. Am J Public Health 1993;83(6):896–8. CrossRef external icon PubMed external icon
- Pierannunzi C, Hu SS, Balluz L. A systematic review of publications assessing reliability and validity of the Behavioral Risk Factor Surveillance System (BRFSS), 2004–2011. BMC Med Res Methodol 2013;13(1):49. CrossRef external icon PubMed external icon
a Some totals may not equal the total number of participants because of missing data. b Inadequate average sleep was defined as 6 hours or less in a 24-hour period. c In the past 30 days on the days when they drank, men who had 5 or more drinks and women who had 4 or more drinks.
a Inadequate average sleep was defined as 6 hours or less in a 24-hour period. b Significant at P < .20. c In the past 30 days on the days when they drank, men who had 5 or more drinks and women who had 4 or more drinks.
The opinions expressed by authors contributing to this journal do not necessarily reflect the opinions of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors’ affiliated institutions.
Exit Notification / Disclaimer Policy
- The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
- Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
- You will be subject to the destination website's privacy policy when you follow the link.
- CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.
CDC.gov Privacy Settings
We take your privacy seriously. You can review and change the way we collect information below.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Cookies used to make website functionality more relevant to you. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests.
Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data.
Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. These cookies may also be used for advertising purposes by these third parties.
Thank you for taking the time to confirm your preferences. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page.

Growing concerns about sleep
Disrupted sleep has been a hallmark of the COVID-19 pandemic. Psychologists explain why it is so crucial for everyone to get back to a healthy routine.
Vol. 52 No. 4 Print version: Page 30

Since the pandemic began, researchers around the world have documented a surge in sleep disorders, with 2 in 3 Americans reporting they are now sleeping either more or less than desired (Partinen, M., The Lancet Neurology , Vol. 20, No. 1, 2021; Stress in America 2021 , APA).
Upended routines, more screen time, increased alcohol consumption, and dissolving boundaries between work and private life are just a few of the factors contributing to problems with sleep. And given the crucial role sleep plays in both physical and mental health, psychologists say it’s important to be proactive in addressing any issues.
“Once sleep is disrupted, it can impact mental and physical health, which may in turn cause further sleep disruption,” said Athena Akrami, PhD, a neuroscientist at University College London who is studying cognitive dysfunction in COVID-19, including sleep disturbances. “A vicious cycle may form that is very difficult to diagnose and treat properly.”
Psychologists are finding a range of sleep changes associated with the pandemic. Some people are sleeping more than ever, while others face shortened schedules, delayed schedules, or insomnia. Those suffering from post-acute sequelae of SARS-CoV-2 infection (PASC), or “long COVID syndrome,” where post-infection symptoms persist for months, are also reporting insomnia, sleep apnea, night sweats, and other problems (“ An Analysis of the Prolonged COVID-19 Symptoms Survey ,” Patient-Led Research Collaborative, 2020).
Even after a stressful experience ends, sleep disturbances may continue—so experts say problems with sleep could persist into the coming months as life begins to normalize.
“The good news is there are treatments that work,” said psychologist James Maas, PhD, a retired professor at Cornell University and an international consultant on sleep. “For many of us spending time at home, this is a wonderful opportunity to regularize our sleep patterns and reap all the benefits that stem from a good night’s rest.”
How sleep went awry
Even before the pandemic, more than 50 million Americans suffered from a sleep disorder, most commonly insomnia, which can involve trouble falling or staying asleep, waking early or throughout the night, or poor sleep quality (“ Sleep and Sleep Disorder Statistics ,” American Sleep Association).
Decades of research have linked chronic sleep deprivation to an increased risk for obesity, heart disease, Type 2 diabetes, and problems with immune function (“ Sleep and Sleep Disorders ,” Centers for Disease Control and Prevention). Sleeping more or less than recommended—typically 7 to 9 hours a night—is a significant predictor of death by any cause (Cappuccio, F. P., et al., Sleep , Vol. 33, No. 5, 2010). Sleep disturbances also hinder social, motor, and cognitive skills and predict suicide risk, depression, and other mental health problems (Bernert, R. A., et al., Current Psychiatry Reports , Vol. 17, 2015; Fang, Y., et al., npj Digital Medicine , Vol. 4, 2021; “ Mental health and sleep ,” Sleep Foundation).
The link between sleep and mental health is just as strong—and just as important—as ever, said Rébecca Robillard, PhD, an assistant professor of psychology at the University of Ottawa, who leads clinical sleep research at the Royal Ottawa Institute of Mental Health Research. In a survey of 5,525 Canadian adults conducted between April and June 2020, she and her colleagues found that sleep problems rose from 36% before the pandemic to more than 50%. Those facing difficulties fell into three categories: less time in bed, more time in bed, or delayed sleep schedule ( Journal of Sleep Research , Vol. 30, No. 1, 2021).
“It makes perfect sense that sleep complaints are on the rise right now, because all of the stay-at-home conditions we experience throughout the day are exactly the factors that we know can affect sleep,” said Susan Rubman, PhD, a behavioral sleep psychologist and assistant professor of clinical psychiatry at the Yale School of Medicine.
People are working, exercising, and socializing inside their homes and even in their bedrooms, which can weaken the cognitive and behavioral associations between those areas and rest or relaxation, Rubman said. We are also facing more stressful situations, limited social support, and disrupted routines, all of which are known to trigger sleep problems (Kutana, S., & Lau, P. H., Canadian Psychology , Vol. 62, No. 1, 2021).
“Aside from being a major life event, living in stay-at-home conditions also increases our exposure to minor hassles and frustrations, which are known to reduce sleep quality,” said Rubman (Lee, S. A., et al., Innovation in Aging , Vol. 4, Supp. 1, 2020).
In addition, less sunlight exposure, more screen time, irregular mealtimes, and increased alcohol use—all of which can interfere with circadian rhythm—are likely to exacerbate sleep problems in people working or learning from home. Rubman said her clients report everything from trouble falling asleep or staying asleep to early wake-up times, poor sleep quality, disrupted sleep cycles, and vivid dreams or nightmares.
Robillard’s findings echo those accounts. Adults who reported higher stress levels, more alcohol use, and more TV exposure were more likely to face new problems with sleep during the pandemic. Women and people with family responsibilities also had more trouble with sleep. Those results build on studies showing high rates of insomnia and other sleep issues among frontline workers early in the pandemic (Herrero-San Martín, A., et al., Sleep Medicine , Vol. 75, 2020; Huang, Y., & Zhao, N., Psychiatry Research , Vol. 288, 2020).
“This points to potential behavioral solutions and also suggests that there are identifiable subgroups of the population that might benefit from additional support right now,” Robillard said.
Establishing healthy routines
Though many Americans have turned to over-the-counter sleep aids such as melatonin— sales of which rose 42% in 2020 , according to the market research firm Nielsen—Maas said the best defense against insomnia is to improve sleep hygiene or participate in cognitive behavioral therapy.
Good sleep hygiene practices start with establishing a regular sleep-wake cycle, said Maas. Go to bed around the same time each night, but not until you feel sleepy, and wake up at the same time each day. Establishing a daytime routine that includes exercise, regular mealtimes, and exposure to sunlight also helps calibrate the body’s circadian rhythm—as does avoiding caffeine within 10 hours and alcohol within 3 hours of bedtime.
Psychologists also recommend reserving the bedroom for sleep and sex but acknowledge that this may not be possible throughout the pandemic.
“As we’re forced to spend more time at home, spaces in our homes have become multipurpose activity centers,” Rubman said.
In such cases, leave the bedroom for extended breaks when possible and avoid working, television, or other digital entertainment in bed, which can lead to a cognitive and behavioral association between bed and wakefulness.
At night, the bedroom should be quiet, dark, and cool, Maas said. He recommends setting the thermostat between 65 and 67 degrees and using a white noise machine or room-darkening shades if needed. Ideally, don’t use electronic devices such as smartphones or laptops in bed, because the light they generate can delay sleep onset.
“If your insomnia lasts for more than 3 weeks, it’s time to go see a trained clinician,” ideally someone who is accredited by the American Academy of Sleep Medicine, Maas said.
Sleep specialists can administer cognitive behavioral therapy for insomnia (CBT-I), which has proven effective in numerous randomized controlled trials (van der Zweerde, T., et al., Sleep Medicine Reviews , Vol. 48, 2019; de Bruin, E. J., et al., Sleep , Vol. 38, No. 12, 2015). CBT-I helps patients improve sleep hygiene and addresses cognitive and behavioral barriers to sleep, for instance by restricting the amount of time spent awake in bed and teaching patients to avoid ruminating. The evidence for CBT-I is so strong that some psychologists say it’s time to shift the focus from additional research testing toward improving public access to such care.
“We know people are struggling with sleep during the pandemic, and we know what works,” Robillard said. “This is now a public health concern that needs to be addressed with large-scale interventions and increased access to CBT-I.”
COVID sleep loss
Patients recovering from COVID-19 are facing their own set of challenges. Though long COVID syndrome is still something of a mystery, researchers are starting to document its symptoms and speculate about its mechanisms.
“Debilitating fatigue, difficulty breathing, and sleep disturbances are some of the main complaints we’re hearing from these individuals,” said Marishka Brown, PhD, director of the National Center on Sleep Disorders Research , part of the National Institutes of Health (NIH).
In a study of 1,733 COVID-19 patients discharged from a Wuhan, China, hospital, 63% experienced fatigue and 26% had problems with sleep (Huang, C., et al., The Lancet , Vol. 397, No. 10270, 2021). Akrami, who is part of the Patient-Led Research Collaborative, a self-organized group of researchers from neuroscience, public policy, and various health disciplines who have all suffered from long COVID, coauthored another study of the syndrome, which is currently under review . She and her colleagues tracked symptoms in more than 3,700 COVID-19 patients for 7 months, finding high rates of fatigue and cognitive dysfunction. More than three-quarters of respondents also had difficulties with sleep, including insomnia, sleep apnea, night sweats, and other issues.
Akrami and her colleagues say the enduring problems with sleep and cognition may be related to inflammation in the brain. Neuroinflammation, which is known to be linked to sleep disorders (Clark, I. A., & Vissel, B., Journal of Neuroinflammation , Vol. 11, 2014), is one symptom of COVID-19. It may be a direct result of damage to the brainstem, or an indirect effect of a dysregulated immune response (Yong, S. J., ACS Chemical Neuroscience , Vol. 12, No. 4, 2021).
“The relationship between long COVID and sleep is a very interesting and important one, but much of what we’ve heard so far is anecdotal,” Akrami said. “We’re working to turn anecdote into rigorous science.”
Other research has shown that melatonin supplements may improve outcomes for COVID-19 patients, possibly by boosting the immune system or simply by enhancing sleep quality, which in turn bolsters health (Zhou, Y., et al., Cell Discovery , Vol. 6, 2020).
Several clinical trials are underway to further investigate melatonin’s efficacy in treating or preventing COVID-19 infection, and NIH has launched the PASC Initiative to study the prolonged health consequences of long COVID, including how it impacts sleep. Akrami and her colleagues are conducting longitudinal studies of cognitive symptoms associated with long COVID and plan to compare the syndrome’s effects with other chronic conditions, such as Alzheimer’s disease, Parkinson’s disease, and lupus. They are also investigating how symptoms of long COVID might change if patients are later vaccinated.
“Sleep needs to be understood as a behavior but also as biology,” Brown said. “By studying sleep quality, timing, and duration—and how they relate to our physical and mental health—sleep researchers have a key role to play in enhancing quality of life during the COVID era.”
Further reading
Sleep guidelines during the COVID-19 pandemic Suni, E., Sleep Foundation, 2020
Sleep and circadian problems during the coronavirus disease 2019 (COVID-19) pandemic: The International COVID-19 Sleep Study (ICOSS) Partinen, M., et al., Journal of Sleep Research , 2020
Trying to make sense of long COVID syndrome Collins, F., NIH Director’s Blog, 2021
Related and recent
Recommended reading.

Contact APA
- Why Do We Sleep, Anyway?
- Sleep, Learning, and Memory
- Consequences of Insufficient Sleep
- Historical and Cultural Perspectives of Sleep
- The Science of Sleep
- Getting the Sleep You Need
At a Glance
- Research suggests that sleep plays an important role in memory, both before and after learning a new task.
- Lack of adequate sleep affects mood, motivation, judgment, and our perception of events.
- Although there are some open questions about the specific role of sleep in forming and storing memories, the general consensus is that consolidated sleep throughout a whole night is optimal for learning and memory.
Features on this page
The learning process and sleep.

Healthy sleep is essential for optimal learning and memory function.
Sleep, learning, and memory are complex phenomena that are not entirely understood. However, animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Research suggests that sleep helps learning and memory in two distinct ways. First, a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently. Second, sleep itself has a role in the consolidation of memory, which is essential for learning new information. Although the exact mechanisms are not known, learning and memory are often described in terms of three functions. Acquisition refers to the introduction of new information into the brain. Consolidation represents the processes by which a memory becomes stable. Recall refers to the ability to access the information (whether consciously or unconsciously) after it has been stored. Each of these steps is necessary for proper memory function. Acquisition and recall occur only during wakefulness, but research suggests that memory consolidation takes place during sleep through the strengthening of the neural connections that form our memories. Although there is no consensus about how sleep makes this process possible, many researchers think that specific characteristics of brainwaves during different stages of sleep are associated with the formation of particular types of memory.

Sleep, Learning, and Memory (1:52)
Dr. Robert Stickgold discusses how sleep plays a role in memory, both before and after a new learning situation.
watch video
Sleep researchers study the role of sleep in learning and memory formation in two ways. The first approach looks at the different stages of sleep (and changes in their duration) in response to learning a variety of new tasks. The second approach examines how sleep deprivation affects learning. Sleep deprivation can be total (no sleep allowed), partial (either early or late sleep is deprived), or selective (specific stages of sleep are deprived).
Sleep Stages and Types of Memory
Different types of memories are formed in new learning situations. Scientists are exploring whether there is a relationship between the consolidation of different types of memories and the various stages of sleep.
The earliest sleep and memory research focused on declarative memory , which is the knowledge of fact-based information, or "what" we know (for example, the capital of France, or what you had for dinner last night). In one research study, individuals engaged in an intensive language course were observed to have an increase in rapid-eye-movement sleep, or REM sleep. This is a stage of sleep in which dreaming occurs most frequently. Scientists hypothesized that REM sleep played an essential role in the acquisition of learned material. Further studies have suggested that REM sleep seems to be involved in declarative memory processes if the information is complex and emotionally charged, but probably not if the information is simple and emotionally neutral. Researchers now hypothesize that slow-wave sleep (SWS) , which is deep, restorative sleep, also plays a significant role in declarative memory by processing and consolidating newly acquired information. Studies of the connection between sleep and declarative memory have had mixed results, and this is an area of continued research.

Sleep plays a major role in the ability to learn new tasks that require motor coordination and performance.
Research has also focused on sleep and its role in procedural memory —the remembering "how" to do something (for example, riding a bicycle or playing the piano). REM sleep seems to plays a critical role in the consolidation of procedural memory. Other aspects of sleep also play a role: motor learning seems to depend on the amount of lighter stages of sleep, while certain types of visual learning seem to depend on the amount and timing of both deep, slow-wave sleep (SWS) and REM sleep.
The Impact of Sleep Deprivation on Learning and Performance
Another area that researchers study is the impact that a lack of adequate sleep has on learning and memory. When we are sleep deprived, our focus, attention, and vigilance drift, making it more difficult to receive information. Without adequate sleep and rest, over-worked neurons can no longer function to coordinate information properly, and we lose our ability to access previously learned information. In addition, our interpretation of events may be affected. We lose our ability to make sound decisions because we can no longer accurately assess the situation, plan accordingly, and choose the correct behavior. Judgment becomes impaired. Being chronically tired to the point of fatigue or exhaustion means that we are less likely to perform well. Neurons do not fire optimally, muscles are not rested, and the body’s organ systems are not synchronized. Lapses in focus from sleep deprivation can even result in accidents or injury. For more information about how sleep deprivation affects performance, see Sleep, Performance, and Public Safety . Low-quality sleep and sleep deprivation also negatively impact mood, which has consequences for learning. Alterations in mood affect our ability to acquire new information and subsequently to remember that information. Although chronic sleep deprivation affects different individuals in a variety of ways (and the effects are not entirely known), it is clear that a good night’s rest has a strong impact on learning and memory.
Open Questions
Although current research suggests that sleep is essential for proper memory function, there are unanswered questions, as in any area of active scientific inquiry. For example, certain medications will significantly, if not entirely, suppress REM sleep. However, patients taking these medications do not report any memory impairment. Similarly, injuries or disease causing lesions to the brainstem (and subsequently eliminating a person’s REM sleep) have not resulted in any obvious loss of the ability to form new memories. Exploration and debate continue.

Mice exhibit an increase in REM sleep after completing a new course through a maze.
© Tetra Images/Corbis
Not all researchers are convinced that sleep plays as prominent a role in memory consolidation as others believe. In experiments in which animals completed a course through a complicated maze, the animals' amount of REM sleep increased after performing the task. Some researchers believe that the increase in REM sleep reflects an increased demand on the brain processes that are involved in learning a new task. Other researchers, however, have suggested that any changes in the amount of REM sleep are due to the stress of the task itself, rather than a functional relationship to learning. Researchers are likewise split with regard to the impact of sleep deprivation on learning and memory. For example, rats often perform much worse on learning tasks after being selectively deprived of REM sleep. This suggests that REM sleep is necessary for the animals’ ability to consolidate the memory of how to perform the task. Some scientists have argued that the observed differences in learning are not actually due to the lack of REM sleep, but may be due to the animals not being as well rested because they were deprived a portion of their sleep.
- Ellenbogen JM, Payne JD, Stickgold R. The role of sleep in declarative memory consolidation: passive, permissive, active or none? Curr Opin Neurobiol. 2006 Dec;16(6):716-22. Epub 2006 Nov 7.
In the view of many researchers, evidence suggests that various sleep stages are involved in the consolidation of different types of memories and that being sleep deprived reduces one’s ability to learn. Although open questions (and debate) remain, the overall evidence suggests that adequate sleep each day is very important for learning and memory.
back to top
This content was last reviewed on December 18, 2007
A resource from the Division of Sleep Medicine at Harvard Medical School
Produced in partnership with WGBH Educational Foundation
About this Site | Site Map | Glossary | Video Index | Technical Help Feedback | Credits | Disclosures | Disclaimers | Understanding Sleep
How Do We Know This?
Getting adequate sleep the first night after learning a new skill is important for improving memory and performance. more

IMAGES
VIDEO
COMMENTS
Impact factor rankings for sleep research journals between 2005 and 2018 2020 Oct;29 (5):e13015. doi: 10.1111/jsr.13015. Epub 2020 Mar 31. Authors Nathaniel S Marshall 1 2 , Camilla M Hoyos 1 2 3 Affiliations 1 CIRUS, Centre for Sleep and Chronobiology, Woolcock Institute of Medical Research, The University of Sydney, Sydney, NSW, Australia.
We then searched for all sleep journals given an impact factor by Thomson Reuters from 2005 to 2018 and all journals given a current H 5 index by Google Scholar. We provide a ranking list specifically for sleep journals that might be useful for researchers to cite when providing context in their applications for employment, promotion and funding.
The Journal of Sleep Research, owned by the European Sleep Research Society, is an international journal dedicated to basic and clinical sleep research. reflecting the progress in this rapidly expanding field, promoting the exchange of ideas between scientists at a global level. Reasons to Publish with Us:
The National Center on Sleep Disorders Research (NCSDR) promotes sleep and circadian scientific advances, from laboratory research to clinical practice, to improve scientific knowledge, transform health care, and advance public health and safety and the well-being of the nation. The NCSDR works toward achieving its mission in the following ways:
The objective of our study was to examine the association between inadequate sleep and frequent mental distress in a population-based sample of US adults. Methods. We conducted a cross-sectional study by using 2018 Behavioral Risk Factor Surveillance System (BRFSS) data that included 273,695 US adults aged 18 to 64.
Several studies have linked insufficient sleep and weight gain. For example, studies have shown that people who habitually sleep less than six hours per night are much more likely to have a higher than average body mass index (BMI) and that people who sleep eight hours have the lowest BMI.
In a survey of 5,525 Canadian adults conducted between April and June 2020, she and her colleagues found that sleep problems rose from 36% before the pandemic to more than 50%. Those facing difficulties fell into three categories: less time in bed, more time in bed, or delayed sleep schedule ( Journal of Sleep Research, Vol. 30, No. 1, 2021).
However, animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Research suggests that sleep helps learning and memory in two distinct ways. First, a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently. Second, sleep itself has a role in ...