Charles Czeisler

Last updated
Charles Czeisler
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Known forHuman sleep medicine
Circadian rhythm research
Awards Aschoff's Rule

National Sleep Foundation: Lifetime Achievement Award
Royal College of London: Adrian Gold Medal
Stanford Medicine Alumni Association: J.E. Wallace Sterling Lifetime Achievement Award in Medicine

Harvard Medical School Division of Sleep Medicine: Peter C. Farrell Prize in Sleep Medicine

Contents

Scientific career
Academic advisors William C. Dement
Elliot D. Weitzman
Website Harvard Neuroscience faculty page
Harvard Medical School faculty profile

Charles Andrew Czeisler (born November 1952) is a Hungarian-American physician and sleep and circadian researcher. [1] He is a leading researcher and author in the fields of the effects of light on human physiology, circadian rhythms and sleep medicine.

Background and education

Czeisler graduated from Harvard College, magna cum laude in 1974, with a degree in biochemistry and molecular biology. His undergraduate thesis was focused on cortisol timing release. [2] He then studied at Stanford University, where he received his Ph.D. in neuro- and bio-behavioral sciences in 1978 and his M.D. in 1981. [3] As a graduate student at Stanford, Czeisler continued his research in Dr. William Dement's lab. [3] [2] Dr. Elliot Weitzman, who both worked with and mentored Czeisler, influenced Czeisler to study sleep. [3] [2] Today, Czeisler is the Baldino Professor of Sleep Medicine and Director of the Division of Sleep Medicine at Harvard Medical School. Additionally, he works as the Division Chief of Sleep Medicine at Brigham and Women's Hospital in Boston, Massachusetts. [3] [4]

Czeisler has spent over 40 years researching the relationship between light and human physiology, particularly, the physiology of the human circadian clock. He teaches a course at Harvard College on Circadian Biology for undergraduate and graduate students. [3] [5] He was ultimately inducted into the Phi Beta Kappa honor society at Harvard College in 1999. In addition to his work at Harvard Medical School and Brigham and Women's Hospital, Czeisler is a Diplomate of the American Board of Sleep Medicine, an elected member of the National Academy of Medicine, the International Academy of Astronautics and the American Clinical and Climatological Association, and a Fellow of the Royal College of Physicians, American Society for Clinical Investigation, and Association of American Physicians. [3]

Family life

Czeisler was one of Tibor Czeisler and Wanda Victoria Murzyn's three children. [1] In 1993, Czeisler married Theresa Lynn Shanahan M.D. They now have three children and live in the Boston area. [1] In his free time, Czeisler enjoys swimming, playing pickleball, and slalom waterskiing. [1]

Research interests

Czeisler's research focus is the neurobiology of human circadian rhythm, the functions and physiology of sleep, the epidemiology and public health consequences of sleep disorders, and the applications of circadian and sleep principles in clinical medicine and occupational safety and health. He also examines the relationship between the circadian oscillator and sleep homeostasis, including a landmark 1980 Science paper demonstrating that sleep episodes were correlated with the circadian phase of the body temperature rhythm at bedtime and not with the length of prior wakefulness. [6] Czeisler's research interests encompass many areas, including the effects of light on human circadian rhythms, the role of sleep and circadian rhythms in metabolism, the impact of shift work on health and productivity, and the effects of melatonin and melatonin receptor agonists on humans.

Czeisler investigates how the physiological system works to reset the human central circadian pacemaker, located in the hypothalamus and called the suprachiasmatic nucleus (SCN). [7] Among his most salient contributions to this research area are a pair of seminal Science original research articles published in 1986 [8] and 1989. [9] The first, entitled "Bright light resets the human circadian pacemaker independent of the timing of the sleep-wake cycle," provided convincing evidence that light influences the human circadian pacemaker, contributing to control of daily variations in physiologic, behavioral, and cognitive function. This finding challenged the then-common idea that synchronization to the 24-hour day accomplished either through social contacts or the sleep-wake schedule. This scientific breakthrough was featured on the front page of The New York Times in June 1989.

Czeisler then led the discovery that light transduced by non-visual input (melanopsin activation) could reset the circadian clock in patients without sight. [10] [11] This indicated that some blind humans can entrain to light through non-visual photoreceptors. Czeisler found that intrinsically photosensitive retinal ganglion cells (ipRGCs) influence both the circadian clock and visual perception, indicating that ipRGCs contribute to "visual" light perception even in the absence of rod and cone photoreceptors. [12] Significantly, this challenged the misconception that rod and cone photoreceptors were the sole receptors for photo-entrainment in humans. [13] [14] In 2002, Czeisler published a study that defended the long-held notion that mammals do not have extra-occular photoreceptors. [15] [16] The findings of his study definitively refuted those of the famous 1998 Science publication, "Extraocular Circadian Phototransduction in Humans," which had reported that bright light behind the knees can help regulated human circadian photoentrainment. [17] Czeisler's study debunked the 1998 publication.

Czeisler has examined the effects of sleep deprivation on the sleep-wake cycle and circadian rhythms, and how this impacts attention performance. [7] [18] He found that bright light duration impacts the circadian pacemaker, melatonin suppression, and sleepiness. [19] [13] He has also discovered that even room lighting can suppress melatonin production and its duration. [20] Czeisler has also dedicated a portion of his career to examining the effects of light timing, duration, intensity, and wavelength on resetting the pacemaker through ipRGCs, which contain the photopigment melanopsin. [13] [14]

Czeisler's work has many important applications. He showed that sleep deprivation could have adverse consequences affecting obesity and diabetes, among other health problems. [19] [13] [21] He has also investigated the effects of chronic sleep deprivation and restriction, night shifts, and circadian disruption, on neurobehavioral performance and metabolism. [7] [13] [21] [22] Furthermore, Czeisler studied how sleep deprivation impairs the psychomotor performance of night shift workers (2009-2014), [19] specifically surgeons (2009-2013) [22] and residents (2010), police officers (2004-2008), [23] and truck drivers (2012). Other research interests of his include studying wakefulness, sleep deprivation and how it can be prevented, and such influences on the clock as exercise and age. [19] Czeisler's research has been applied to medicine, space travel, and night occupations including shift-work. [7] [22]

As of August 2023, Czeisler has published more than 300 scientific articles, which have accumulated more than 80,000 citations, leading to an h-index of 138. [24]

Summary of selected contributions

Advocacy in sleep health and occupational safety

In a 1999 interview with the Harvard Gazette regarding his team's characterization of a near-24-hour human circadian period, Czeisler noted that "accepting the near-24-hour period means that all the ideas about daily human rhythms that we take for granted must be rethought." [39] Understanding the internal circadian period makes problems dealing with jet-lag, night shifts, and sleep schedules in orbit more approachable

Guided by the significant real-life implications of his research, Czeisler is a strong advocate for healthy sleep habits. In consulting with the Boston Celtics, Portland Trail Blazers, and Minnesota Timberwolves for the National Basketball Association (NBA) and Cleveland Browns for the National Football League (NFL), he emphasized sleep as the "third pillar of health" alongside nutrition and exercise. [40] He instituted structural changes to the teams' schedules to allow for healthier sleep habits, including pushing morning practices into the afternoon and the '2 a.m. rule' which prevents players from traveling if they are going to arrive at their hotel later than 2:00 am. [40] [41]

According to Czeisler, sleep deficiency poses a significant individual and public health hazard as demonstrated by the significant contribution of drowsiness to workplace accidents and motor vehicle accidents. In an interview with the Harvard Business Review, he explains that companies should seek to address this problem by setting behavioral expectations and scheduling policies for employees to avoid accruing sleep deficit. [42]

In order to implement improved occupational sleep scheduling and sleep health standards as effective public policy, Czeisler has served on and consulted to numerous national and international health advisory agencies. As President of the National Sleep Foundation from 2005–2006, he chaired the Presidential Task Force on Sleep and Public Policy in order to develop model legislation regarding physician-in-training work hours. [3] [43] [44] As a Team Leader of the Human Performance Factors, Sleep and Chronobiology Team at the NASA National Space Biomedical Research Institute, Czeisler has been responsible for developing sleep-wake schedule guidelines for NASA astronauts and mission control personnel. [3]

Czeisler is also a member of the Brigham Health Sleep Matters Initiative,(SMI) which was created "to implement evidence-based clinical treatments for sleep and circadian disorders, and to change the culture of sleep." In 2018, the National Safety Council recognized the SMI for its outstanding commitment to safety, for which it was awarded the prestigious Green Cross for Safety Award. [45]

In 2018, Czeisler penned a powerful Perspective in The New England Journal of Medicine entitled "Housing Immigrant Children - The Inhumanity of Constant Illumination" [46] in which he harshly criticized the constant light exposure to which children were being subjected in detention centers while awaiting immigration processing, as this did not allow for exposure to light-dark cycles central to circadian regulation.

In 2023, together with Harvard Medical School Professor Elizabeth Klerman, Czeisler organized a seminar at the Harvard Radcliffe Institute to discuss whether daylight saving time should be eliminated or made permanent—a debate they call “another clash between scientific evidence and politics.” The seminar brought together researchers, policymakers, and members of the general public for a discussion.

A more complete listing of agencies to which Czeisler has consulted [46] can be found at his Harvard Faculty Profile. [47]

Honors and awards

Czeisler's research in sleep medicine, circadian rhythms, and professional advocacy for occupational health and safety, are the subject of various honors and awards included below:

Czeisler is a co-inventor of several U.S. patents:

During October 2019, a Festschrift was organized to celebrate Czeisler's career. The event was held in the Harvard Biological Laboratories, where Czeiser's colleagues, former pupils, friends, and family gathered to present plenary speeches and breakthrough scientific talks. The occasion brought together approximately 75 researchers from six different continents.

A more complete list of honors and awards bestowed upon Czeisler can be found on his Harvard Faculty Profile

Related Research Articles

Free-running sleep is a rare sleep pattern whereby the sleep schedule of a person shifts later every day. It occurs as the sleep disorder non-24-hour sleep–wake disorder or artificially as part of experiments used in the study of circadian and other rhythms in biology. Study subjects are shielded from all time cues, often by a constant light protocol, by a constant dark protocol or by the use of light/dark conditions to which the organism cannot entrain such as the ultrashort protocol of one hour dark and two hours light. Also, limited amounts of food may be made available at short intervals so as to avoid entrainment to mealtimes. Subjects are thus forced to live by their internal circadian "clocks".

<span class="mw-page-title-main">Circadian rhythm</span> Natural internal process that regulates the sleep-wake cycle

A circadian rhythm, or circadian cycle, is a natural oscillation that repeats roughly every 24 hours. Circadian rhythms can refer to any process that originates within an organism and responds to the environment. Circadian rhythms are regulated by a circadian clock whose primary function is to rhythmically co-ordinate biological processes so they occur at the correct time to maximize the fitness of an individual. Circadian rhythms have been widely observed in animals, plants, fungi and cyanobacteria and there is evidence that they evolved independently in each of these kingdoms of life.

<span class="mw-page-title-main">Suprachiasmatic nucleus</span> Part of the brains hypothalamus

The suprachiasmatic nucleus or nuclei (SCN) is a small region of the brain in the hypothalamus, situated directly above the optic chiasm. It is responsible for regulating sleep cycles in animals. Reception of light inputs from photosensitive retinal ganglion cells allow it to coordinate the subordinate cellular clocks of the body and entrain to the environment. The neuronal and hormonal activities it generates regulate many different body functions in an approximately 24-hour cycle.

Non-24-hour sleep–wake disorder is one of several chronic circadian rhythm sleep disorders (CRSDs). It is defined as a "chronic steady pattern comprising [...] daily delays in sleep onset and wake times in an individual living in a society". Symptoms result when the non-entrained (free-running) endogenous circadian rhythm drifts out of alignment with the light–dark cycle in nature. Although this sleep disorder is more common in blind people, affecting up to 70% of the totally blind, it can also affect sighted people. Non-24 may also be comorbid with bipolar disorder, depression, and traumatic brain injury. The American Academy of Sleep Medicine (AASM) has provided CRSD guidelines since 2007 with the latest update released in 2015.

<span class="mw-page-title-main">Circadian rhythm sleep disorder</span> Family of sleep disorders that affect the timing of sleep

Circadian rhythm sleep disorders (CRSD), also known as circadian rhythm sleep–wake disorders (CRSWD), are a family of sleep disorders that affect the timing of sleep. CRSDs cause a persistent pattern of sleep/wake disturbances that arise either by dysfunction in one's biological clock system, or by misalignment between one's endogenous oscillator and externally imposed cues. As a result of this misalignment, those affected by circadian rhythm sleep disorders can fall asleep at unconventional time points in the day, or experience excessive daytime sleepiness if they resist. These occurrences often lead to recurring instances of disrupted rest and wakefulness, where individuals affected by the disorder are unable to go to sleep and awaken at "normal" times for work, school, and other social obligations. Delayed sleep phase disorder, advanced sleep phase disorder, non-24-hour sleep–wake disorder and irregular sleep–wake rhythm disorder represents the four main types of CRSD.

Ignacio Provencio is an American neuroscientist and the discoverer of melanopsin, an opsin found in specialized photosensitive ganglion cells of the mammalian retina. Provencio served as the program committee chair of the Society for Research on Biological Rhythms from 2008 to 2010.

In the study of chronobiology, entrainment refers to the synchronization of a biological clock to an environmental cycle. An example is the interaction between circadian rhythms and environmental cues, such as light and temperature. Entrainment helps organisms adapt their bodily processes with the timing of a changing environment. For example, entrainment is manifested during travel between time zones, hence why humans experience jet lag.

Emery Neal Brown is an American statistician, computational neuroscientist, and anesthesiologist. He is the Warren M. Zapol Professor of Anesthesia at Harvard Medical School and at Massachusetts General Hospital (MGH), and a practicing anesthesiologist at MGH. At MIT he is the Edward Hood Taplin Professor of Medical Engineering and professor of computational neuroscience, the associate director of the Institute for Medical Engineering and Science, and the Director of the Harvard–MIT Program in Health Sciences and Technology.

Light effects on circadian rhythm are the response of circadian rhythms to light.

Richard Ernest Kronauer was the Gordon McKay Professor of Mechanical Engineering, emeritus, at Harvard University. Though experienced with research in both fluid mechanics and applied mathematics.

<span class="mw-page-title-main">Second wind (sleep)</span> Sleep phenomenon

Second wind, a colloquial name for the scientific term wake maintenance zone, is a sleep phenomenon in which a person, after a prolonged period of staying awake, temporarily ceases to feel drowsy, often making it difficult to fall asleep when exhausted. They are the result of circadian rhythms cycling into a phase of wakefulness. For example, many people experience the effects of a second wind in the early morning even after an entire night without sleep because it is the time when they would normally wake up.

A chronobiotic is an agent that can cause phase adjustment of the circadian rhythm. That is, it is a substance capable of therapeutically entraining or re-entraining long-term desynchronized or short-term dissociated circadian rhythms in mammals, or prophylactically preventing their disruption following an environmental insult such as is caused by rapid travel across several time zones. The most widely recognized chronobiotic is the hormone melatonin, secreted at night in both diurnal and nocturnal species.

Rütger Wever was a German scientist, known for his significant contributions to the field of Chronobiology, including some of the first experiments on humans in time isolated environments.

Studies, which include laboratory investigations and field evaluations of population groups that are analogous to astronauts, provide compelling evidence that working long shifts for extended periods of time contributes to sleep deprivation and can cause performance decrements, health problems, and other detrimental consequences, including accidents, that can affect both the worker and others.

Derk-Jan Dijk is a researcher of sleep and circadian rhythms. As at 2024 he is a Distinguished Professor at the University of Surrey and the director of its Sleep Research Centre.

A constant routine protocol is a common method used in human circadian rhythm research to study internally generated, or endogenous, circadian rhythms without the effect of external, or exogenous, influences. In the method, subjects are kept in constant conditions for at least 24 hours. These include constant light and temperature, as well as constant semi-recumbent posture. In addition, subjects' food intake is evenly distributed throughout the protocol, and subjects are typically not allowed to sleep for the duration. While in these conditions, subjects are often assessed for a number of variables of interest. Two of the most common and best understood of these variables are core body temperature and melatonin.

Dr. Debra J. Skene is a chronobiologist with specific interest in the mammalian circadian rhythm and the consequences of disturbing the circadian system. She is also interested in finding their potential treatments for people who suffer from circadian misalignment. Skene and her team of researchers tackle these questions using animal models, clinical trials, and most recently, liquid chromatography-mass spectrometry. Most notably, Skene is credited for her evidence of a novel photopigment in humans, later discovered to be melanopsin. She was also involved in discovering links between human PER3 genotype and an extremely shifted sleep schedules categorized as extreme diurnal preference. Skene received her Bachelor of Pharmacy, Master of Science, and Ph.D. in South Africa.

<span class="mw-page-title-main">Charmane Eastman</span> American academic research scientist in chronobiology

Charmane Eastman is an American academic research scientist whose career has focused on studying circadian rhythms and their relationships to sleep, jet lag, and shift work. She has also studied winter depression, more properly known as seasonal affective disorder (SAD). Of special focus are the effects of bright light and melatonin on circadian rhythms.

Anne-Marie Chang is a researcher in the fields of sleep and circadian rhythms and is currently an Assistant Professor of Bio-behavioral Health at Pennsylvania State University. She earned her Ph.D. in neuroscience from Northwestern University in 2003.

Elizabeth Klerman is a professor of neurology at Harvard Medical School. Her research focuses on applying circadian and sleep research principles to human physiology and pathophysiology. She also uses mathematical analysis and modeling to study human circadian, sleep, and objective neurobehavioral performance and subjective (self-reported) mood and alertness rhythms.

References

  1. 1 2 3 4 Czeisler, Charles A. E-mail interview. 24 April 2013.
  2. 1 2 3 "Charles Czeisler." Interview. The Science Network. N.p., June 2009. Web. 23 Apr. 2013. <http://thesciencenetwork.org/programs/sleep-2009/charles-czeisler-2>
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 "Faculty Profile: Charles A. Czeisler, PhD, MD, FRCP." Division of Sleep Medicine: Harvard Medical School. Harvard College, n.d. Web. 10 Apr. 2013.
  4. ↑ "Division of Sleep Medicine." Brigham and Women's Hospital. The Division of Sleep Medicine, 25 Jan. 2013. Web. 11 Apr. 2013.
  5. ↑ "MCB 186. Circadian Biology: From Cellular Oscillators to Sleep Regulation." Harvard: FAS Registrar's Office. The President and Fellows of Harvard College, n.d. Web. 11 Apr. 2013. "MCB 186. Circadian Biology: From Cellular Oscillators to Sleep Regulation | FAS Registrar's Office". Archived from the original on 2015-06-10. Retrieved 2013-04-13.
  6. ↑ Czeisler, C. A.; Weitzman, E. d; Moore-Ede, M. C.; Zimmerman, J. C.; Knauer, R. S. (1980-12-12). "Human sleep: its duration and organization depend on its circadian phase". Science. 210 (4475): 1264–1267. doi:10.1126/science.7434029. ISSN   0036-8075. PMID   7434029.
  7. 1 2 3 4 Joseph S. Takahashi, Hee-Kyung Hong, Caroline H. Ko & Erin L. McDearmon "The genetics of mammalian circadian order and disorder: implications for physiology and disease" Nature Reviews Genetics 9, 764-775 (October 2008)
  8. ↑ Czeisler, C. A.; Allan, J. S.; Strogatz, S. H.; Ronda, J. M.; Sánchez, R.; Ríos, C. D.; Freitag, W. O.; Richardson, G. S.; Kronauer, R. E. (1986-08-08). "Bright light resets the human circadian pacemaker independent of the timing of the sleep-wake cycle". Science. 233 (4764): 667–671. doi:10.1126/science.3726555. ISSN   0036-8075. PMID   3726555.
  9. ↑ Czeisler, C. A.; Kronauer, R. E.; Allan, J. S.; Duffy, J. F.; Jewett, M. E.; Brown, E. N.; Ronda, J. M. (1989-06-16). "Bright light induction of strong (type 0) resetting of the human circadian pacemaker". Science. 244 (4910): 1328–1333. doi:10.1126/science.2734611. ISSN   0036-8075. PMID   2734611.
  10. ↑ Klein, Torsten; Martens, Heinz; Dijk, Derk-Jan; Kronauer, Richard E.; Seely, Ellen W.; Czeisler, Charles A. (June 1993). "Circadian Sleep Regulation in the Absence of Light Perception: Chronic Non-24-Hour Circadian Rhythm Sleep Disorder in a Blind Man With a Regular 24-Hour Sleep—Wake Schedule". Sleep. 16 (4): 333–343. doi:10.1093/sleep/16.4.333. ISSN   1550-9109. PMID   8341894.
  11. ↑ Czeisler, Charles A.; Shanahan, Theresa L.; Klerman, Elizabeth B.; Martens, Heinz; Brotman, Daniel J.; Emens, Jonathan S.; Klein, Torsten; Rizzo, Joseph F. (1995-01-05). "Suppression of Melatonin Secretion in Some Blind Patients by Exposure to Bright Light". New England Journal of Medicine. 332 (1): 6–11. doi: 10.1056/nejm199501053320102 . ISSN   0028-4793. PMID   7990870.
  12. ↑ Yamazaki S, Goto M, Menaker M (1999). "No Evidence for Extraocular Photoreceptors in the Circadian System of the Syrian Hamster". Journal of Biological Rhythms. 14 (3): 197–201. doi:10.1177/074873099129000605. PMID   10452331. S2CID   2102758.
  13. 1 2 3 4 5 Münch M, Bromundt V (Dec 2012). "Light and chronobiology: implications for health and disease". Dialogues in Clinical Neuroscience. 14 (4): 448–53. doi:10.31887/DCNS.2012.14.4/mmuench. PMC   3553574 . PMID   23393421.
  14. 1 2 Higuchi S, Hida A, Tsujimura S, Mishima K, Yasukouchi A, Lee SI, Kinjyo Y, Miyahira M (2013). "Melanopsin Gene Polymorphism I394T Is Associated with Pupillary Light Responses in a Dose-Dependent Manner". PLOS ONE. 8 (3): e60310. Bibcode:2013PLoSO...860310H. doi: 10.1371/journal.pone.0060310 . PMC   3610661 . PMID   23555953.
  15. 1 2 Wright, Kenneth P.; Czeisler, Charles A. (2002-07-26). "Absence of Circadian Phase Resetting in Response to Bright Light Behind the Knees". Science. 297 (5581): 571. doi:10.1126/science.1071697. ISSN   0036-8075. PMID   12142528. S2CID   12121143.
  16. 1 2 Post, Sarah. "Bright Light behind the Knees Is Just Bright Light behind the Knees." Genome News Network. Craig Venter Institute, 16 Aug. 2002. Web. 22 Apr. 2013.
  17. 1 2 Campbell, Scott S., and Patricia S. Murphy. "Extraocular Circadian Phototransduction in Humans." Science. American Association for the Advancement of Science, 16 Jan. 1998. Web. 23 Apr. 2013.
  18. ↑ Möller-Levet CS, Archer SN, Bucca G, Laing EE, Slak A, Kabiljo R, Lo JC, Santhi N, von Schantz M, Smith CP, Dijk DJ (Mar 2013). "Effects of insufficient sleep on circadian rhythmicity and expression amplitude of the human blood transcriptome". Proc. Natl. Acad. Sci. USA. 110 (12): E1132–41. doi: 10.1073/pnas.1217154110 . PMC   3607048 . PMID   23440187.
  19. 1 2 3 4 "Annual Sleep in American Poll Exploring Connections with Communications Technology Use and Sleep". National Sleep Foundation. March 7, 2011.
  20. ↑ Chang, Anne-Marie; Aeschbach, Daniel; Duffy, Jeanne F.; Czeisler, Charles A. (2015-01-27). "Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness". Proceedings of the National Academy of Sciences. 112 (4): 1232–1237. doi: 10.1073/pnas.1418490112 . ISSN   0027-8424. PMC   4313820 . PMID   25535358.
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  24. ↑ "Charles A. Czeisler". scholar.google.com. Retrieved 2023-08-08.
  25. ↑ Czeisler, Charles A.; Weitzman, Elliot D.; Moore-Ede, Martin C.; Zimmerman, Janet C.; Knauer, Richard S. (1980-12-12). "Human Sleep: Its Duration and Organization Depend on Its Circadian Phase". Science. 210 (4475): 1264–1267. doi:10.1126/science.7434029. ISSN   0036-8075. PMID   7434029.
  26. ↑ Weitzman, Elliot D.; Czeisler, Charles A.; Coleman, Richard M.; Spielman, Arthur J.; Zimmerman, Janet C.; Dement, William; Pollak, Charles P. (1981-07-01). "Delayed Sleep Phase Syndrome: A Chronobiological Disorder With Sleep-Onset Insomnia". Archives of General Psychiatry. 38 (7): 737–746. doi:10.1001/archpsyc.1981.01780320017001. ISSN   0003-990X. PMID   7247637.
  27. ↑ Czeisler, Charles A.; Allan, James S.; Strogatz, Steven H.; Ronda, Joseph M.; Sánchez, Ramiro; Ríos, C. David; Freitag, Walter O.; Richardson, Gary S.; Kronauer, Richard E. (1986-08-08). "Bright Light Resets the Human Circadian Pacemaker Independent of the Timing of the Sleep-Wake Cycle". Science. 233 (4764): 667–671. doi:10.1126/science.3726555. ISSN   0036-8075. PMID   3726555.
  28. ↑ Czeisler, Charles A.; Kronauer, Richard E.; Allan, James S.; Duffy, Jeanne F.; Jewett, Megan E.; Brown, Emery N.; Ronda, Joseph M. (1989-06-16). "Bright Light Induction of Strong (Type 0) Resetting of the Human Circadian Pacemaker". Science. 244 (4910): 1328–1333. doi:10.1126/science.2734611. ISSN   0036-8075. PMID   2734611.
  29. ↑ Ca, Czeisler; Tl, Shanahan; Eb, Klerman; H, Martens; Dj, Brotman; Js, Emens; T, Klein; Jf, Rizzo (1995-01-05). "Suppression of melatonin secretion in some blind patients by exposure to bright light". The New England Journal of Medicine. 332 (1): 6–11. doi: 10.1056/NEJM199501053320102 . ISSN   0028-4793. PMID   7990870.
  30. ↑ Boivin, D. B.; Duffy, J. F.; Kronauer, R. E.; Czeisler, C. A. (1996-02-08). "Dose-response relationships for resetting of human circadian clock by light". Nature. 379 (6565): 540–542. doi:10.1038/379540a0. ISSN   0028-0836. PMID   8596632. S2CID   4307825.
  31. ↑ Czeisler CA, Duffy JF, Shanahan TL, Brown EN, Mitchell JF, Rimmer DW, Ronda JM, Silva EJ, Allan JS, Emens JS, Dijk DJ, Kronauer RE (June 1999). "Stability, precision, and near-24-hour period of the human circadian pacemaker". Science. 284 (5423): 2177–81. doi:10.1126/science.284.5423.2177. PMID   10381883. S2CID   8516106.
  32. ↑ Lockley, Steven W.; Cronin, John W.; Evans, Erin E.; Cade, Brian E.; Lee, Clark J.; Landrigan, Christopher P.; Rothschild, Jeffrey M.; Katz, Joel T.; Lilly, Craig M.; Stone, Peter H.; Aeschbach, Daniel; Czeisler, Charles A.; Harvard Work Hours, Health and Safety Group (2004-10-28). "Effect of reducing interns' weekly work hours on sleep and attentional failures". The New England Journal of Medicine. 351 (18): 1829–1837. doi: 10.1056/NEJMoa041404 . ISSN   1533-4406. PMID   15509816.
  33. ↑ Landrigan, Christopher P.; Rothschild, Jeffrey M.; Cronin, John W.; Kaushal, Rainu; Burdick, Elisabeth; Katz, Joel T.; Lilly, Craig M.; Stone, Peter H.; Lockley, Steven W.; Bates, David W.; Czeisler, Charles A. (2004-10-28). "Effect of reducing interns' work hours on serious medical errors in intensive care units". The New England Journal of Medicine. 351 (18): 1838–1848. doi: 10.1056/NEJMoa041406 . ISSN   1533-4406. PMID   15509817.
  34. ↑ Barger, Laura K.; Cade, Brian E.; Ayas, Najib T.; Cronin, John W.; Rosner, Bernard; Speizer, Frank E.; Czeisler, Charles A.; Harvard Work Hours, Health, and Safety Group (2005-01-13). "Extended work shifts and the risk of motor vehicle crashes among interns". The New England Journal of Medicine. 352 (2): 125–134. doi: 10.1056/NEJMoa041401 . ISSN   1533-4406. PMID   15647575.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  35. ↑ Czeisler, Charles A.; Walsh, James K.; Roth, Thomas; Hughes, Rod J.; Wright, Kenneth P.; Kingsbury, Lilliam; Arora, Sanjay; Schwartz, Jonathan R. L.; Niebler, Gwendolyn E.; Dinges, David F.; U.S. Modafinil in Shift Work Sleep Disorder Study Group (2005-08-04). "Modafinil for excessive sleepiness associated with shift-work sleep disorder". The New England Journal of Medicine. 353 (5): 476–486. doi: 10.1056/NEJMoa041292 . ISSN   1533-4406. PMID   16079371.
  36. ↑ Duffy, Jeanne F.; Cain, Sean W.; Chang, Anne-Marie; Phillips, Andrew J. K.; Münch, Mirjam Y.; Gronfier, Claude; Wyatt, James K.; Dijk, Derk-Jan; Wright, Kenneth P.; Czeisler, Charles A. (2011-09-13). "Sex difference in the near-24-hour intrinsic period of the human circadian timing system". Proceedings of the National Academy of Sciences of the United States of America. 108 (Suppl 3): 15602–15608. doi: 10.1073/pnas.1010666108 . ISSN   1091-6490. PMC   3176605 . PMID   21536890.
  37. ↑ Buxton, Orfeu M.; Cain, Sean W.; O’Connor, Shawn P.; Porter, James H.; Duffy, Jeanne F.; Wang, Wei; Czeisler, Charles A.; Shea, Steven A. (2012-04-11). "Adverse Metabolic Consequences in Humans of Prolonged Sleep Restriction Combined with Circadian Disruption". Science Translational Medicine. 4 (129): 129ra43. doi:10.1126/scitranslmed.3003200. ISSN   1946-6234. PMC   3678519 . PMID   22496545.
  38. ↑ Chang, Anne-Marie; Aeschbach, Daniel; Duffy, Jeanne F.; Czeisler, Charles A. (2015-01-27). "Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness". Proceedings of the National Academy of Sciences of the United States of America. 112 (4): 1232–1237. doi: 10.1073/pnas.1418490112 . ISSN   1091-6490. PMC   4313820 . PMID   25535358.
  39. ↑ "Human Biological Clock Set Back an Hour." Human Biological Clock Set Back an Hour. N.p., n.d. Web. 24 Apr. 2013.
  40. 1 2 Ortiz, Maria B. "To Sleep, Perchance to Win." ESPN. ESPN Internet Ventures, 4 December 2009. Web. 23 April 2013.
  41. ↑ Flannery, Paul. "Person of Interest: Charles Czeisler." Boston Magazine. Metrocorp Inc., May 2011. Web. 22 Apr. 2013.
  42. ↑ Czeisler, Charles. "Sleep Deficit: The Performance Killer A Conversation with Charles A. Czeisler by Bronwyn Fryer." Harvard Business Review. Bronwyn Fryer. Boston: Harvard Business Review, October 2006.
  43. ↑ "Past Presidents." Past Sleep Research Society Presidents. N.p., n.d. Web. 13 Apr. 2013.
  44. ↑ "Resident Work Hours." - Past SRS Government Relations Initiative. N.p., n.d. Web. 13 Apr. 2013. Archived 2013-12-03 at the Wayback Machine
  45. ↑ Chadra, Karen. "NSC Announces Winners of its Prestigious Green Cross for Safety Awards". National Safety Council. Retrieved 2020-06-19.
  46. 1 2 Czeisler, Charles A. (2018-07-12). "Housing Immigrant Children - The Inhumanity of Constant Illumination". The New England Journal of Medicine. 379 (2): e3. doi:10.1056/NEJMp1808450. ISSN   1533-4406. PMID   29932841. S2CID   49384225.
  47. ↑ Charles Czeisler Profile
  48. ↑ "Aschoff's Rule." Society for Research on Biological Rhythms. N.p., n.d. Web. 24 Apr. 2013.[ permanent dead link ]
  49. ↑ "NIOSH to Seek Applications for 2006 Director's Award." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, n.d. Web. 13 Apr. 2013.
  50. ↑ "Call For Nominations: National Sleep Foundation's 2014 Lifetime Achievement Award." National Sleep Foundation. N.p., n.d. Web. 13 Apr. 2013. Archived 2013-04-06 at the Wayback Machine
  51. ↑ http://www.rsm.ac.uk/academicboard/downloads/agenda-papers07-10.pdf [ permanent dead link ]
  52. ↑ "Distinguished Scientist Award." SRS. N.p., n.d. Web. 13 Apr. 2013
  53. ↑ "Charles Czeisler of BWH Receives Public Policy Award from American Academy of Sleep Medicine" AASM. N.p., n.d. Web. 13 Apr. 2013.
  54. ↑ "Farrell Prize in Sleep Medicine | Division of Sleep Medicine @ Harvard Medical School". sleep.med.harvard.edu. Retrieved 2020-06-19.
  55. ↑ "2019 Alumni Awards". Alumni Association. Retrieved 2020-06-19.
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