ASSESSMENT OF DAYTIME SLEEPINESS BEFORE AND AFTER LIGHT EXPOSURE
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-050221 from National Center For Research Resources
Abstract: This study was designed to investigate whether an increase in circadian rhythm amplitude accomplished through exposure to bright indoor light during the morning hours causes a concurrent decrease in daytime sleepiness. The multiple sleep latency test(MSLT) and subjective measures of alertness will be used.
Keywords: BIOPERIODICITY, CIRCADIAN RHYTHMS, BRAIN, REGULATORY CENTERS, SLEEP, ENVIRONMENTAL HEALTH, LIGHTING, NEUROLOGIC MANIFESTATIONS, SLEEP DISORDERS, OPTICS, LIGHT INTENSITY, THERAPY EVALUATION, HUMAN, phototherapy, ENVIRONMENT CONTROLLED, photobiology, HUMAN, CLINICAL
Sponsored Links Excellgen http://Excellgen.com
DISRUPTED SLEEP IN THE ELDERLY--CIRCADIAN ETIOLOGY
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-190607 from National Center For Research Resources IRG: RIRG
Abstract: To determine the effect of varying the intensity of a single, 6.5 hour pulse of continuous bright light in older subjects. A secondary purpose is to examine the effects of varying intensities of light on plasma melatonin concentration in older subjects. Data will be compared to similar data previously collected in young subjects.
Keywords: circadian rhythm, human old age (65+), human therapy evaluation, phototherapy, sleep disorder, disease /disorder etiology, light intensity, melatonin, blood chemistry, clinical research, human subject
CLINICAL METHOD OF DETERMINING THE PHASE OF THE CIRCADIAN TIMING SYSTEM IN MAN
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-100363 from National Center For Research Resources
Abstract: This series of studies attempts to develop and validate an alternative to the methods of spectral analysis/waveform eduction for determining circadian phase. Our proposed alternative requires only two days of laboratory study, compared with the weeks of laboratory study required for those methods. Used CDMAS this year.
Keywords: diurnal rhythm, method development, human data
DEVELOPMENT OF A CLINICAL METHOD FOR DETERMINING THE CIRCADIAN PHASE
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-080264 from National Center For Research Resources
Abstract: This series of studies attempts to develop and validate an alternative to the methods of spectral analysis/waveform eduction for determining circadian phase. Our proposed alternative requires only two days of laboratory study, compared with the weeks of laboratory study required for those methods. Used CDMAS this year.
Keywords: diagnosis design /evaluation, diurnal rhythm, brain electrical activity, electroencephalography, human clinical subject
DEVELOPMENT OF CLINICAL METHOD FOR DETERMINING PHASE, ETC
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-150594 from National Center For Research Resources
Abstract: This series of studies attempts to develop and validate an alternative to the methods of spectral analysis/waveform education for determining circadian phase. Our proposed alternative requires only two days of laboratory study, compared with the weeks of laboratory study required for those methods. Used CDMAS this year.
Keywords: analytical method, circadian rhythm, method development, diagnosis design /evaluation, computer processing of clinical data, computer program /software, human subject
Project start date: 1998-12-01
Project end date: 1999-11-30
Sponsored Links Excellgen http://Excellgen.com
COMPARISON OF PRAVASTATIN AND LOVASTATIN
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-080293 from National Center For Research Resources
Abstract: This is a double-blind comparison of the effects these drugs have on nocturnal sleep and daytime performance/alertness measures in healthy adult males.
Keywords: antihypercholesterolemic agent, drug adverse effect, lovastatin, sleep disorder, attention, performance, sleep, human clinical subject, human volunteer subject, male
DIURNAL NATURE AND PULSATILITY OF PARATHYROID HORMONE
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-090375 from National Center For Research Resources
Abstract: This is a Clinical Associate Physician project designed to characterize the diurnal and pulsatile nature of parathyroid hormone in normal healthy volunteers. Insight into mechanisms controlling calcium homeostasis may lead to further insights into pathological conditions such as osteoporosis.
Keywords: diurnal rhythm, parathyroid hormone, calcium, clinical study /trial, homeostasis, human subject, human volunteer subject
REPRODUCTIVE FUNCTION IN WOMEN--CIRCADIAN INTERACTION
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-100380 from National Center For Research Resources
Abstract: The purpose of this study is to examine the interaction between the reproductive cycle and the circadian rhythms of temperature, hormones, and behavioral measures in women age 18-35. Completed inpatient study (scatter beds). Uses CDMAS only.
Keywords: diurnal rhythm, female reproductive system, reproduction, sex cycle, behavior, body temperature, hormone, adolescence (12-20), female, human data, young adult human (21-44)
CIRCADIAN RHYTHM OF RESPIRATORY CONTROL DURING 24-64 HOURS EXTENDED WAKEFULNESS
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-150536 from National Center For Research Resources
Abstract: The purpose of this study is to examine the daily rhythm of breathing and respitory control during a 24-64 hour period of continuous wakefulness to better understand how the respitory control system is related to the circadian timing system in humans.
Keywords: circadian rhythm, pulmonary respiration, wakefulness, clinical trial, respiration regulatory center, clinical research, human subject
CIRCADIAN PHASE ESTIMATION AFTER SCHEDULED VS UNSCHEDULED ROUTINE
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-100436 from National Center For Research Resources
Abstract: The purpose of this study is to examine how the daily temperature cycle correlates with natural variation in hormone levels, kidney activity, and psycho-motor performance when patients are on their normal routine and to compare that with results from similar testing obtained when they are free from external time cycles.
Keywords: body temperature, diurnal rhythm, hormone regulation /control mechanism, kidney function, neuroendocrine system, psychomotor function, human subject
Sponsored Links Excellgen http://Excellgen.com
CLINICAL TRIAL OF THE EFFECT OF BRIGHT LIGHT IN MEN VS WOMEN
Charles A Czeisler, Professor Of Medicine
Institution:
Grant 5M01RR002635-120518 from National Center For Research Resources
Abstract: The purpose of this study is to examine how the daily light-dark cycle in the environment affects the timing of hormone release, the timing of the daily cycle of body temperature, the sleep-wake cycle, and the inner body functions which ordinarily vary with the time of day. These studies may help to understand the basis of certain diseases and how light may be used in this treatment.
Keywords: diurnal rhythm, phototherapy, sex difference, body temperature regulation, clinical trial, female, hormone regulation /control mechanism, male, clinical research, human subject
CIRCADIAN RHYTHMS IN PATIENTS WITH CHRONIC SPINAL CORD LESIONS
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-150581 from National Center For Research Resources
Abstract: The purpose of this study is to examine how the daily light-dark cycle in the enviroment affects the timing of hormone release, the timing of the daily cycle of body temperature, the sleep-wake cycle, and the inner body functions which ordinarily vary with the time of day.
Keywords: circadian rhythm, neuroendocrine system, spinal cord injury, body temperature, hormone metabolism, sleep, wakefulness, clinical research, human subject
Project start date: 1998-12-01
Project end date: 1999-11-30
PHOTOTHERAPY TREATMENT OF SHIFT ROTATION INSOMNIA
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-190468 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate the impact of phototherapy on the daytime sleep and nocturnal performance of individuals during a combined laboratory and field based simulation of a complete shift rotation.
Keywords: human therapy evaluation, occupational health /safety, phototherapy, sleep disorder, clinical research, human subject
Sponsored Links Excellgen http://Excellgen.com
CLINICAL TRIAL OF MELATONIN AS HYPNOTIC
Charles A Czeisler, Professor Of Medicine
Institution:
Grant 5M01RR002635-120502 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate the impact of exercise on sleep and daytime performance.
Keywords: hormone regulation /control mechanism, melatonin, sedative /hypnotic, clinical trial, exercise, performance, sleep, clinical research, human subject
LIGHT PULSES ON CIRCADIAN ENTRAINMENT
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-190586 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate the ability of multiple, short duration high-level light intensities to keep the biological clock synchronized to a long term 24-hour duty and sleep/wake schedule.
Keywords: circadian rhythm, photostimulus, biological clock, light intensity, neuroendocrine system, sleep, wakefulness, clinical research, human subject
CIRCADIAN RHYTHMS OF BLIND PERSONS
Charles A Czeisler, Professor Of Medicine
Institution:
Grant 5M01RR002635-120295 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate circadian rhythms in both young and older blind individuals to determine if their circadian rhythms are in synchrony with the external environment. Subjects undergo a circadian phase evaluation 3-5 times during a 3-month period.
Keywords: blindness, diurnal rhythm, age difference, aging, clinical research, human subject
Sponsored Links Excellgen http://Excellgen.com
CIRCADIAN RHYTHMS IN BLIND PERSONS
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-150295 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate circadian rhythms in both young and older blind individuals to determine if their circadian rhythms are in synchrony with the external environment. Subjects undergo a circadian phase evaluation 3-5 times during a 3-month period.
Keywords: blindness, circadian rhythm, age difference, aging, environmental adaptation, clinical research, human subject
EARLY AWAKENING IN ELDERLY--CIRCADIAN EVALUATION/TREATMENT/PHOTOTHERAPY
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-100290 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate circadian rhythms in both healthy and depressed elderly individuals who wake earlier than desired in the morning. After initial evaluation, subjects may be treated with bright light (phototherapy) in an attempt to change the time of their daily sleep episode.
Keywords: diurnal rhythm, human therapy evaluation, phototherapy, sleep disorder, wakefulness, depression, human old age (65+), photobiology, visible light, human subject
EARLY AWAKENING IN HEALTHY VS. DEPRESSED ELDERLY--CIRCADIAN EVALUATION
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-070290 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate circadian rhythms in both healthy and depressed elderly individuals who wake earlier than desired in the morning. After initial evaluation, subjects may be treated with bright light (phototherapy) in an attempt to change the time of their daily sleep episode.
Keywords: diurnal rhythm, human therapy evaluation, phototherapy, sleep disorder, wakefulness, depression, human old age (65-84), photobiology, visible light, human clinical subject
EARLY AWAKENING IN ELDERLY--CIRCADIAN EVALUATION/TREATMENT/PHOTOTHERAPY
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-080290 from National Center For Research Resources
Abstract: The purpose of this study is to evaluate circadian rhythms in both healthy and depressed elderly individuals who wake earlier than desired in the morning. After initial evaluation, subjects may be treated with bright light (phototherapy) in an attempt to change the time of their daily sleep episode.
Keywords: diurnal rhythm, human therapy evaluation, phototherapy, sleep disorder, wakefulness, depression, human old age (65+), photobiology, visible light, human clinical subject
DETERMINE EFFECT OF L-754,030 ON LIGHT-INDUCED MELATONIN
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-150571 from National Center For Research Resources
Abstract: The purpose of this study is to determine where L-754,030 blocks light- induced melatonin suppression and is safe in healthy young men.
Keywords: antidepressant, antiemetic, drug screening /evaluation, male, melatonin, clinical trial phase II /III /IV, hormone regulation /control mechanism, neuroendocrine system, clinical research, human subject
CIRCADIAN RHYTHMS OF BLIND PERSONS
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-070295 from National Center For Research Resources
Abstract: The purpose of this study is 1)to determine if the disruption of the sleep-wake cycle of blind subjects may be caused by a circadian rhythm disorder, 2)to find a simple way to determine whether or not a blind person is in synchrony with the geophysical day, most likely using activity recording, and 3)to attain the pathophysiological basis for a possible therapy of these specific rhythm disorders.
Keywords: blindness, diurnal rhythm, sleep disorder, body physical activity, sleep, wakefulness, human clinical subject
DISRUPTED SLEEP IN THE ELDERLY--CIRCADIAN ETIOLOGY
Charles A Czeisler
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5M01RR002635-070263 from National Center For Research Resources
Abstract: The purpose of this series of studies is to investigate changes in the circadian system that occur with age, and to test the hypothesis that sleep disturbances commonly found in the elderly are a result of underlying changes in circadian function.
Keywords: aging, diurnal rhythm, human old age (65-84), sleep disorder, sleep, human clinical subject
Sponsored Links Excellgen http://Excellgen.com
Grants awarded to Charles A Czeisler
Effects Of Attending Surgeon And Obstetrician Fatigue On Operating Room Safety
Charles A Czeisler, Professor Of Medicine
Brigham And Women´s Hospital
Grant 1R01HL095472-01A1 from National Heart, Lung, And Blood Institute IRG: HSOD
Abstract: Up to 98,000 patients die each year in the United States due to medical error. While nurse and physician-in-training sleep deprivation has been found to significantly increase the risk of medical errors and occupational injuries, very little information has emerged on the relationship between senior (attending) physician work hours and patient safety. In surgery and obstetrics, the hours of attending physicians can match or exceed those of physicians-in-training. Whether such long work hours might degrade the performance of experienced attending physicians as severely as that of resident-physicians, however, is unknown. Experienced attending physicians may be less prone to attentional failures and performance decrements than younger physicians-in-training who have a stronger physiologic drive to sleep when awake for long hours. Conversely, sleep quality tends to deteriorate with age, which could lead to a buildup of sleep debt and an increased risk of fatigue-related error. In a prior intensive observational study, we found that physicians-in-training working recurrent 24-hour shifts made 36% more serious medical errors and five times as many serious diagnostic errors as those whose scheduled work is limited to 16 consecutive hours. We propose to conduct an intensive study of attending surgeons and obstetricians that will measure intra-operative processes of care and errors. In doing so, we will draw upon both our own experience conducting intensive studies of sleep and medical error, as well as emerging tools to quantify surgical safety and outcomes. Our specific aims will be 1. To test the hypothesis that the incidence of technical performance problems - as prospectively assessed by direct intra-operative observation, as well as healthcare provider reports - will be significantly higher during surgical cases performed the day following an overnight case (i.e., a case occurring between 12am and 7am) compared with matched cases on days without any preceding night work. 2. To test the hypothesis that the incidence of attentional failures, miscommunications, and teamwork problems - as prospectively assessed by direct intra-operative observation, as well as provider reports - will be significantly higher during surgical cases performed the day following an overnight case compared with matched cases on days without any preceding night work. 3. To test the hypothesis that the incidence of intra-operative serious medical errors (adverse events and near misses) - as assessed by a combination of direct observation, provider reports, and systematic chart surveillance - will be significantly higher during surgical cases performed the day following an overnight case compared with matched cases on days without any preceding night work. The proposed study will build upon our prior studies of sleep deprivation and safety to help develop an understanding of the effects of extended work hours across medical specialties and levels of training. Between 44,000 and 98,000 patients die each year in the United States due to medical error. We have previously found that the traditional long work hours of physicians-in-training greatly increase their risk of making medical errors, but there remains considerable debate in the medical community about whether experienced physicians´ performance deteriorates with sleep deprivation. We plan to conduct an intensive study in the operating room using established direct observational techniques and measurement tools to determine if sleep deprivation increases senior surgeons´ and obstetricians´ risk of error
Project start date: 2009-04-01
Project end date: 2013-03-31
After-Effects Of Entrainment On Human Circadian Period
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5R01NS040982-04 from National Institute Of Neurological Disorders And Stroke IRG: ZRG1
Abstract: Until recently, it was widely believed that the intrinsic period of the human circadian pacemaker was 25 h. However, using a forced desynchrony laboratory-based protocol in which the confounding effects of light and activity on circadian period assessment are controlled, we have found that the intrinsic period of the circadian system is close to 24 h (average 24.18 h). Similarly, we have found that blind individuals without light perception (NPL) living in society have circadian rhythms of melatonin which free-run with a period averaging approximately 24.5 h. While these data also suggest that the intrinsic circadian period is closer to 24 h than previously thought, the discrepancy between blind and sighted subjects suggests that the circadian pacemaker may be affected by unidentified factors. One likely factor is the absence of after- effects of entrainment to the 24 h light-dark cycle in non- entrained blind individuals, who may thus have a longer circadian period than sighted subjects observed upon release from entrainment. Similarly, blind subjects entrained by non-photic time cues in society may differ from sighted and non-entrained blind subjects upon release from entrainment due to differences in after-effects of photic- and non-photic synchronizers. We propose to investigate the role of after-effects of entrainment by assessing the circadian period of blind individuals under field and forced desynchrony conditions and comparing them to healthy sighted subjects who have been and will be studied. Specifically we will test the hypotheses that 1) the endogenous circadian period of the melatonin and temperature rhythms is significantly longer in NPL subjects than sighted subjects; 2) the circadian period of NPL subjects observed in field conditions in which non-photic time cues are non-uniformly distributed is significantly longer than when assessed under controlled forced desynchrony conditions; 3) those NPL subjects who are entrained in society but who are insensitive to light will have, on average, a significantly shorter circadian period than those NPL subjects who are not entrained in society. This work has significant implications for understanding how intrinsic period relates to prior entrainment and the role of after-effects of entrainment. It will help define the limits of entrainment for non-photic synchronizers and will evaluate the efficacy of such time cues to treat circadian rhythm sleep-wake disorders in both the blind and sighted populations.
Keywords: blindness, circadian rhythm, environmental adaptation, photobiology, photostimulus, body temperature, controlled environment, cue, field study, melatonin, rest, sleep, adult human (21+), clinical research, electroencephalography, electromyography, electrooculography, human subject, polysomnography, questionnaire
Project start date: 2001-07-15
Project end date: 2005-06-30
5R01NS040982-04 (2004): $317500
5R01NS040982-03 (2003): $317500
1R01NS040982-01A1 (2001): $317500
Charles A Czeisler
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Grant 5P30HL101299-02 from National Heart, Lung, And Blood Institute
Abstract: This NHLBI PSO application requests funding for two years salary plus appropriate start up funds for a newly independent investigator whose research will complement the research underway in the Brigham & Women´s Hospital´s (BWH) Division of Sleep Medicine´s research center. The research center´s mission is to forge a path of discovery in sleep medicine and to train the next generation of leaders in academic sleep medicine. The Division has 31 faculty, 20 postdoctoral fellows and over 50 support staff, with the majority of effort spent on research. These research activities are funded by annual research grants of ~$11.8 million. The Division has a number of interacting research programs and cores, covering most aspects of sleep and circadian physiology, as well as sleep pathophysiology (mechanisms and therapy for the sleep disorders). However, we have identified an important area of research that is not currently well studied in our center, namely the interaction of the circadian system with disease. In particular, there is a critical gap in our understanding of the role of the circadian timing system in causing the very robust morning increase in adverse cardiovascular events (strokes, myocardial infarction, and sudden cardiac death) in vulnerable patient groups. We have identified a spectacular newly independent investigator whose research has moved in this direction and who is poised for promotion to Assistant Professor of Medicine. Should this P03 award be made, the institution is committed to providing appropriate research facilities for this individual, including use of the BWH Intensive Physiological Monitoring Unit in the Center for Clinical Investigation, a component of the Harvard Catalyst-Clinical and Translation Science Center. In addition, the investigator will fully utilize the many career development resources in the BWH Center for Faculty Development and Diversity. Together with close research and career mentorship from senior faculty in the Division´s research center, we anticipate that a PSO award will lead to important discoveries concerning the role of the circadian system in the day/night pattern of adverse cardiovascular events, and greatly facilitate the career development of one of the most promising future leaders in academic sleep medicine. A PSO award will lead to important discoveries concerning the role of the circadian system in the very robust day/night pattern of adverse cardiovascular events, and greatly facilitate the career development of one of the most promising future leaders in academic sleep medicine
Project start date: 2009-09-30
Project end date: 2011-08-31
Budget start date: 1-SEP-2010
Budget end date: 31-AUG-2011
PFA/PA: RFA-OD-09-005
5P30HL101299-02 (2010): $360608
1P30HL101299-01 (2009): $372480
SLEEP, AGING AND CIRCADIAN RHYTHM DISORDERS
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Grant 3P01AG009975-14S3 from Office Of The Director, National Institutes Of Health
Abstract: This award is issued in response to Notice OD-09-060, Recovery Act Administrative Supplements Providing Summer Research Experiences for Students and Science Educators. Sleep in older people is marked by difficulty with initiation, frequent arousals, and early awakening. While the consequences of acute sleep deprivation have been investigated in older people, very little is known about the consequences of the chronic insufficient sleep experienced by many older people. Moreover, the interaction between the misalignment of circadian phase, so common in older people, and chronic insufficient sleep has not been studied. Our proposal seeks to address that gap in our knowledge by using a well-established laboratory model to study what differences may exist between the sleep efficiency of older and younger subjects under conditions of chronic sleep restriction (ratio 19 hours scheduled wake 5 hours scheduled sleep), carried out on a forced-desynchrony protocol, and by assessing the recuperative capabilities under conditions of sleep extension following this restriction. The design of our human subjects protocol provides a tremendous opportunity to investigate an array of cognitive performance measures under these conditions of chronic sleep restriction and subsequent sleep extension. The Polysomnography Core of the proposed Program Project will provide accurate and reliable scoring of polysomnographic recordings from subjects participating in the experimental protocol as well as from prospective subjects during the screening process. A ´metabolic aging´ experiment has been included in our proposal with the goal of understanding the endocrine and cardiovascular consequences of sleep restriction in both young and older subjects. In the previous cycle of this Program Project, it was hypothesized that sleep difficulties in older people might be due to loss of neurons in the ventrolateral preoptic nucleus (VLPO). A critical component of this proposal is the continued pursuit of this mammalian model for sleep regulation during aging. With aging, there is a loss of neurons in the ventrolateral preoptic nucleus (VLPO), which is necessary for normal sleep, with aging, and we hypothesize that rats with partial lesions of the VLPO are a high fidelity model for sleep in older people. We will test this model for its validity for older people by performing a series of studies that parallel the human components of this Program Project grant, both in older rats and in rats with partial VLPO lesions. We hypothesize that the VLPO lesioned rat is a good model for sleep in older people who have VLPO cell loss, and to use this model to test the efficacy of treatment designed to restore VLPO function, which we hope will restore sleep as well as improve cognitive and motor skills that deteriorate with aging and poor sleep. The core components - Administrative, Analytic and Polysomnography - are effective in providing support across projects and most importantly, providing for cohesion of efforts across the entire Program Project. The results of this research will have important implications for understanding the role of sleep in the health, safety, and neurocognitive functions of older people
Project start date: 2009-08-01
Project end date: 2010-10-31
Budget start date: 1-AUG-2009
Budget end date: 31-OCT-2010
3P01AG009975-14S3 (2009): $97773
Training In Sleep, Circadian & Respiratory Neurobiology
Charles A Czeisler, Professor Of Medicine
Brigham And Women´s Hospital
research Administration
boston, Ma 02115
Grant 5T32HL007901-10 from National Heart, Lung, And Blood Institute IRG: ZHL1
Abstract: The Program for Training in Sleep, Circadian and Respiratory Neurobiology is designed to provide a structured, comprehensive program to train outstanding individuals for academic positions in the broad field of sleep disorders medicine with specific expertise in basic science, patient-oriented or applied research. Trainees will include (1) pro-doctoral graduate students; (2) pre-doctoral short-term summer minority medical students; (3 ) post-doctoral trainees with an M.D. degree who will have completed clinical training; (4) post-doctoral trainees who will have completed their Ph.D. degree with or without an M.D. degree. There are three training tracks Track I for pre-doctoral and post-doctoral fellows requiring fundamental training in basic science research techniques; Track II for pre-doctoral and post-doctoral fellows requiring fundamental training in the techniques of patient-oriented and applied research; and Track III for post-doctoral fellows who intend to continue research at a level of demonstrated expertise. There are eight established faculty preceptors with great experience and success at training pro-doctoral and/or post-doctoral fellows, well-funded research programs and outstanding resources that trainees will utilize. Of their trainees over the past ten years, over 90% have remained in academic medicine (distribution 40% in training; 53% faculty positions; 7% private practice/industry). Forty percent of those trainees still in academic medicine have already received external grant support as PI or Co-I (more than half of which are NIH or other Federal grants). These preceptors will provide trainees with an opportunity to participate directly in on-going research programs in many diverse areas of sleep, circadian and respiratory neurobiology from molecular genetics to patient-oriented applied research. Junior faculty who have established active, independent research programs have been included as associate preceptors. The training program consists of core required courses and activities, elective courses and activities, and intensive research. Multidisciplinary research is promoted, together with exposure to collaborative research. Funds are requested to support four pre-doctoral graduate students, three pre-doctoral short-term summer minority medical students and six post-doctoral trainees. This established formal program meets a nationally recognized need for qualified investigators in sleep disorders medicine
Project start date: 1998-08-01
Project end date: 2008-06-30
5T32HL007901-10 (2007): $534728
5T32HL007901-09 (2006): $534256
5T32HL007901-08 (2005): $309547
Sponsored Links Excellgen http://Excellgen.com
5T32HL007901-07 (2004): $531016
2T32HL007901-06 (2003): $520981
EVALUATION OF THE POTENTIAL FOR TRANSLATION TO PRACTICE OF A SLEEP DISORDERS MANA
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Abstract: The need for 24/7 policing places high physical and psychological demands on police officers that contribute to a high level of fatigue. Frequent overnight shifts and long work weeks leads to acute and chronic partial sleep deprivation in addition to misalignment of circadian phase. As part of the CDC Health Protection Research Initiative Evaluation of Workplace Health Promotion Research Projects, we have recently conducted a study entitled ´Sleep Disorders Management, Health and Safety in Police´ that aimed to develop a novel sleep disorders detection and treatment program, ´Operation Healthy Sleep´, on the health, safety, and productivity of police officers. The program included sleep health and hygiene education, caffeine-use education and a large- scale screening, diagnosis and treatment program for clinical sleep disorders. We have recently completed the program in two major police forces, the Massachusetts State Police and the Philadelphia Police Department, using a randomized clinical design to evaluate the overall impact of this health promotion program on officer health, workplace performance, and safety, as derived from police department databases. Approximately 2000 officers attended the educational component of the program. More than 1000 of these officers were also screened for sleep disorders and our results show that police officers have a particularly high prevalence of clinical sleep disorders, with obstructive sleep apnea and insomnia the most common conditions. In the current proposal, we will conduct a detailed evaluation of the Operation Healthy Sleep program and investigate the advantages and disadvantages of our approach though the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) framework to health behavior interventions. We will take advantage of the excellent relationships that we have developed with the police departments, unions and officers during the course of implementing Operation Healthy Sleep to conduct a series of focus group interviews with the stake-holders in the program, in addition to analysis of quantitative data on participation in the various stages of the program. We will also evaluate the cost, feasibility and sustainability of the Operation Health Sleep program through cost-benefit analysis, including quantitative analysis of objective health, safety and productivity outcomes. Finally, we will evaluate the external validity and potential for translation of the Operation Healthy Sleep program nationally by comparing health, safety and productivity outcomes obtained from the primary police samples with those obtained from a nationwide sample of more than 4000 police officers participating in our concurrent web-based survey sleep disorders, fatigue, health and safety. If viable, our ultimate aim is to disseminate this program to practitioners, policymakers and researchers nationwide to reduce fatigue and stress in law enforcement officers, improve their workplace performance, enhance officers´ health and safety and, consequently, improve public safety. The need for 24/7 policing, with frequent overnight shifts and long work weeks, places high physical and psychological demands on police officers that contribute leads to acute and chronic partial sleep deprivation and high levels of fatigue. Furthermore, we have shown that police officers have a high prevalence of clinical sleep disorders, particularly obstructive sleep apnea and insomnia. We have recently implemented Operation Healthy Sleep in the Massachusetts State Police and Philadelphia Police Department which includes sleep health and hygiene education, caffeine-use education and a large-scale screening, diagnosis and treatment program for clinical sleep disorders. In the current proposal, we will conduct a detailed evaluation of the Operation Healthy Sleep program and investigate the advantages and disadvantages of our approach with the view to developing a nationwide program to enhance the sleep, alertness and performance of police officers and ultimately both their and the public´s health and safety
Keywords: No Project Terms available
Project start date: 2007-09-30
Project end date: 2010-09-29
Budget start date: 30-SEP-2008
Budget end date: 29-SEP-2010
PFA/PA: RFA-CD-07-004
5R01OH009403-02 (2008): $0
TREATMENT OF CIRCADIAN SLEEP DISORDERS W/BRIGHT LIGHT
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5R01MH045130-05 from National Institute Of Mental Health IRG: PCB
Abstract: The light-dark cycle is the most important environmental synchronizer of circadian rhythms in most species. In fact, it has been shown that critically-timed light exposures can reset circadian phase. Animal studies have demonstrated that the magnitude and direction of these phase shifts are dependent on the intensity and the duration of the light exposure (described by a dose response curve [DRC]) as well as on the initial circadian phase of the light exposure (described by a phase response curve (PRC]). Based on our preliminary data, we hypothesize that (1) scheduled exposure to bright light stimuli can reproducibly enhance the resetting of the human circadian pacemaker, such that steady state phase shifts can be achieved within three days; (2) the timing of exposure to darkness/sleep modulates the resetting effect of bright light on the human circadian system; (3) the resetting response to a three-cycle light-dark stimulus is dose dependent (as measured by the illuminance of the light stimulus); (4) the resetting response to a cyclic bright light stimulus is dependent on the initial circadian phase of light exposure; (5) exposure to bright light can be used therapeutically in the treatment of circadian sleep disorders. A series of experiments are proposed utilizing methodologies that allow direct measurement of circadian phase both before and after exposure to bright light. These experiments will accomplish 5 specific aims (1) quantification of the extent to which exposure to bright light can facilitate the resetting of the human circadian pacemaker; (2) characterization of the manner in which darkness/sleep modulates the resetting effect of bright light stimuli; (3) establishment of a dose response curve for the resetting of the human circadian pacemaker by light; (4) determination of the phase response curve of the human circadian pacemaker to a cyclic stimulus of bright light and darkness, and; (5) evaluation of the therapeutic effectiveness of controlled exposure to light and darkness in the treatment of circadian sleep disorders. This work has important implications for the treatment of circadian rhythm sleep disorders such as Delayed Sleep Phase Syndrome, Shift Work Dyssomnia, and Rapid Time Zone Change (Jet-lag) Syndrome. The ability to rapidly reset circadian phase with bright light provides a means of correcting the misalignment of phase seen in these disorders. However, since individuals appear to vary in their sensitivity to light and since the efficacy of light seems to have a strong saturating response curve, careful quantification of these processes will be essential before practical therapies can be devised.
Keywords: diurnal rhythm, human therapy evaluation, phototherapy, sleep disorder, human ecology, psychobiology, human subject, human volunteer subject, mathematical model, photostimulus
Project start date: 1989-09-01
Project end date: 1994-08-31
5R01MH045130-05 (1993): $476748
5R01MH045130-04 (1992): $489082
SLEEP, AGING AND CIRCADIAN RHYTHM DISORDERS
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Grant 5P01AG009975-15 from National Institute On Aging
Abstract: Sleep in older people is marked by difficulty with initiation, frequent arousals, and early awakening. While the consequences of acute sleep deprivation have been investigated in older people, very little is known about the consequences of the chronic insufficient sleep experienced by many older people. Moreover, the interaction between the misalignment of circadian phase, so common in older people, and chronic insufficient sleep has not been studied. Our proposal seeks to address that gap in our knowledge by using a well-established laboratory model to study what differences may exist between the sleep efficiency of older and younger subjects under conditions of chronic sleep restriction (ratio 19 hours scheduled wake 5 hours scheduled sleep), carried out on a forced-desynchrony protocol, and by assessing the recuperative capabilities under conditions of sleep extension following this restriction. The design of our human subjects protocol provides a tremendous opportunity to investigate an array of cognitive performance measures under these conditions of chronic sleep restriction and subsequent sleep extension. The Polysomnography Core of the proposed Program Project will provide accurate and reliable scoring of polysomnographic recordings from subjects participating in the experimental protocol as well as from prospective subjects during the screening process. A ´metabolic aging´ experiment has been included in our proposal with the goal of understanding the endocrine and cardiovascular consequences of sleep restriction in both young and older subjects. In the previous cycle of this Program Project, it was hypothesized that sleep difficulties in older people might be due to loss of neurons in the ventrolateral preoptic nucleus (VLPO). A critical component of this proposal is the continued pursuit of this mammalian model for sleep regulation during aging. With aging, there is a loss of neurons in the ventrolateral preoptic nucleus (VLPO), which is necessary for normal sleep, with aging, and we hypothesize that rats with partial lesions of the VLPO are a high fidelity model for sleep in older people. We will test this model for its validity for older people by performing a series of studies that parallel the human components of this Program Project grant, both in older rats and in rats with partial VLPO lesions. We hypothesize that the VLPO lesioned rat is a good model for sleep in older people who have VLPO cell loss, and to use this model to test the efficacy of treatment designed to restore VLPO function, which we hope will restore sleep as well as improve cognitive and motor skills that deteriorate with aging and poor sleep. The core components - Administrative, Analytic and Polysomnography - are effective in providing support across projects and most importantly, providing for cohesion of efforts across the entire Program Project. The results of this research will have important implications for understanding the role of sleep in the health, safety, and neurocognitive functions of older people
Project start date: 1991-08-01
Project end date: 2011-06-30
Budget start date: 1-JUL-2010
Budget end date: 30-JUN-2011
5P01AG009975-15 (2010): $1113126
5P01AG009975-14 (2009): $1110153
Sponsored Links Excellgen http://Excellgen.com
5P01AG009975-13 (2008): $1110153
5P01AG009975-12 (2007): $1132809
2P01AG009975-11 (2006): $1173143
Sleep Disorders Management, Health And Safety In Police
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5R01OH008496-03 from National Institute For Occupational Safety And Health IRG: ZCD1
Abstract: Sleep Disorders may cause the deaths of up to 20,000 people each year in the United States, and lead to loss of health, poor quality of life, and decreased job productivity. Because of their career-long exposure to long work hours and frequent overnight shift duty, police officers are at extremely high risk of suffering sleep disorders, including obstructive sleep apnea, insomnia, and shift work sleep disorder. Our research group has conducted numerous studies of sleep deprivation and interventions to reduce the adverse effects of sleep deprivation on safety, health, and performance of personnel in numerous occupational groups police, physicians in training (residents), astronauts, air force pilots, nuclear power plant workers, truckers, and industrial workers. We have a successful track record of disseminating research results to inform local and national policy changes. We propose to conduct a randomized, prospective study of the effect of a novel Sleep Disorders Detection and Treatment Program - Operation Healthy Sleep. Because of the high prevalence of sleep disorders among police, and the profound effect of sleep disorders on performance, safety, and job experience, we hypothesize that implementation of Operation Healthy Sleep will 1. improve the mean nightly sleep and alertness of police officers; 2. improve police officer safety, as determined by a. decreased rates of motor vehicle crashes; b. decreased on-the-job injuries; 3. improve police officer productivity, as determined by a. increased arrest and conviction rates; b. decreased response time and completion time (clear time) for calls on duty; c. decreased rates of civilian complaints and inappropriate use of force; 4. improve officers and families job satisfaction and ability to cope with shift work. By establishing a comprehensive sleep disorders detection and treatment program and rigorously testing its effects across a range of health, safety, and work outcomes, we hope to develop a model program that can be broadly replicated to improve the safety, health, and performance of police officers, as well as other shift workers, across the country.
Keywords: occupational health /safety, outcomes research, police, sleep disorder, attention, diagnosis, health care service evaluation, injury prevention, job satisfaction, clinical research, human subject
Project start date: 2004-09-30
Project end date: 2007-09-29
SENSITIZATION OF HUMAN CIRCADIAN RESPONSES TO LIGHT
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Grant 1R01HL094654-01A1 from National Heart, Lung, And Blood Institute
Abstract: Sleep disorders affect 35-40% of adults, resulting in diminished quality of life, and increased morbidity, mortality, and risk of automobile and occupational accidents. Circadian rhythm sleep disorders form a distinct class of sleep disorders characterized by misalignment between the timing of sleep and the circadian pacemaker. While light therapy can be an effective treatment of circadian rhythm sleep disorders, there are numerous practical limitations. Light is the most powerful signal from the environment that influences and regulates daily biological rhythms. It is well-established that the irradiance, duration, and timing of light exposure all affect the response of the circadian system. While it was once thought that these responses were mediated through the visual system, it is now known that there is a network of intrinsically photosensitive retinal ganglion cells (ipRGCs) that mediate circadian responses to light. Other new studies have demonstrated that recent light exposure history affects the circadian response to light in humans. These recent findings have important implications for the use of light to treat circadian rhythm disorders, including delayed and advanced sleep phase disorders, shift work sleep disorder, and jet lag, and they may also have relevance for the use of light to treat seasonal affective disorder. Up to now, little attention has been paid to the duration or intensity of light exposure prior to such light treatments. We now have evidence that the human circadian system can become desensitized to light during long exposures and evidence that it can be sensitized to light by prior exposure to dim light. These recent findings suggest that light treatment protocols that sensitize the circadian system prior to the light treatment will be more effective than those currently in use. The studies we propose will examine the effect on the human circadian system of four different durations of dim-light sensitization prior to a standardized light treatment. These results will be compared within subjects in a randomized cross-over design study in which each healthy subject will receive a control treatment and a light treatment with prior dim-light sensitization. We will also include one group of delayed sleep phase disorder patients to test these mechanisms in the target patient population. Our findings will provide an important step in understanding how new knowledge about the circadian photoreceptive system can be used to refine and provide better treatment options for circadian rhythm disorders. Circadian rhythm disorders are a class of sleep disorders characterized by misalignment between the timing of sleep and the circadian pacemaker. Light therapy can effectively treat these disorders, but the intensity and duration of light exposure required to do so has limited its practical use. Here we will test how pre exposure to dim light can enhance the response of the circadian system to light therapy, resulting in shorter treatments that have greater practical application
Keywords: 21+ years old; Acetamide, N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-; Actinotherapy; Acute; Adult; Affect; Animals; Attention; Automobiles; Biological Clocks; Biological Rhythm; Biological Rhythm and Oscillation; Blood Plasma; Brain; Cell Communication and Signaling; Cell Nucleus; Cell Signaling; Circadian Dysregulation; Circadian Rhythm Disorder; Circadian Rhythm Sleep Disorders; Circadian Rhythms; Clinical; Clock, Biologic; Cognitive; Crossover Design; Designs, Cross-Over; Disease; Disorder; Disturbed Nyctohemeral Rhythm; Diurnal Rhythm; Encephalon; Encephalons; Environment; Exposure to; Eye; Eyeball; Ganglion Cells (Retina); History; Human; Human, Adult; Human, General; Image; Intracellular Communication and Signaling; Jet Lag; Jet Lag Syndrome; Jetlag; Jetlag Syndrome; Knowledge; Laboratories; Lateral; Light; Light Therapy; Man (Taxonomy); Man, Modern; Measures; Mediating; Melatonin; Morbidity; Morbidity - disease rate; Mortality; Mortality Vital Statistics; Nervous; Nervous System, Brain; Nucleus; Nyctohemeral Rhythm; Occupational Accidents; Pathway interactions; Patients; Performance; Phase; Photoradiation; Photoradiation Therapy; Photoreceptor Cell; Photoreceptors; Photoreceptors, Vertebrate; Photosensitive Cell; Phototherapy; Physiologic pulse; Plasma; Preoptic Areas; Production; Property; Property, LOINC Axis 2; Protocols, Treatment; Pulse; Pupil light reflex; QOL; Quality of life; RGM; Randomized; Recording of previous events; Regimen; Regulation; Reticuloendothelial System, Serum, Plasma; Retinal Ganglion Cells; Risk; Rods and Cones; SCHED; Schedule; Seasonal Affective Disorder; Seasonal Mood Disorder; Serum, Plasma; Shift-Work Sleep Disorder; Sight; Signal Transduction; Signal Transduction Systems; Signaling; Site; Sleep; Sleep Arousal Disorders; Sleep Disorders; Sleep Disorders, Circadian Rhythm; Sleep Stages; Sleep-Wake Cycle Disorders; Sleep-Wake Schedule Disorders; System; System, LOINC Axis 4; Testing; Time; Time Zone Change Syndrome; Time Zone Syndrome; Treatment Protocols; Treatment Regimen; Treatment Schedule; Twenty-Four Hour Rhythm; Vertebrate Photoreceptors; Vision; Visual Receptor; Visual System; Visual system structure; adult human (21+); alertness; application in practice; biological signal transduction; body clock; circadian; circadian clock; circadian pacemaker; circadian process; daily biorhythm; day shift; desensitization; disease/disorder; diurnal variation; effective therapy; extrastriate visual cortex; imaging; internal clock; light effects; light intensity; light treatment; neural; neurobehavioral; night shift; night work; novel; pathway; patient population; practical application; preoptic region; public health relevance; pupillary light reflex; pupillary reflex; randomisation; randomization; randomly assigned; relating to nervous system; response; retinal ganglion; seasonal depression; shift work; sleep problem
Relevance: Circadian rhythm disorders are a class of sleep disorders characterized by misalignment between the timing of sleep and the circadian pacemaker. Light therapy can effectively treat these disorders, but the intensity and duration of light exposure required to do so has limited its practical use. Here we will test how pre exposure to dim light can enhance the response of the circadian system to light therapy, resulting in shorter treatments that have greater practical application
Project start date: 2010-07-01
Project end date: 2014-06-30
Budget start date: 1-JUL-2010
Budget end date: 30-JUN-2011
PFA/PA: PA-07-070
1R01HL094654-01A1 (2010): $317500
EFFICACY OF MELATONIN TREATMENT IN A PHASE ADVANCE MODEL OF INSOMNIA
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Grant 5R01HL093279-02 from National Heart, Lung, And Blood Institute
Abstract: provided by investigator) Melatonin is a hormone produced by the pineal gland at night. The timing of its release is controlled by the circadian timing system. Its timing can be suppressed or reset by exposure to light through a multisynaptic pathway from the eye through the suprachiasmatic nucleus, the master circadian clock. Exogenous melatonin supplementation has been reported to act in two ways in humans as a soporific (sleep-promoting) and a chronobiotic (to reset circadian phase), thus affecting both of the neurobiologic systems that interact to regulate sleep and wakefulness. Melatonin supplements have been reported to be an effective treatment for circadian rhythm sleep disorders, including shift work dyssomnia, jet-lag, delayed sleep phase syndrome, and sleep disruption suffered by many blind individuals. However, in a recent meta-analysis, the vast majority of these reports were excluded because they were not randomized controlled trials. The conclusion was that melatonin is not efficacious for sleep complaints associated with jetlag and shift work. In view of the widespread, uncontrolled, over-the-counter use of melatonin for treating sleep complaints in the general population, a randomized controlled trial of melatonin is essential to evaluate efficacy in treatment of transient insomnia. The current application will test the chronobiotic and sleep promoting effects of melatonin in a phase advance model of insomnia. Subjects will be administered either melatonin or placebo before a scheduled sleep episode which is advanced by several hours, simulating eastward travel. Under these conditions, low sleep pressure and the timing of the circadian clock make sleep particularly difficult. We will measure sleep and multiple physiologic rhythms controlled by the circadian after melatonin or placebo administration, and use precise analytic methods to determine the impact of melatonin on sleep and the human circadian timing system. This study will provide important information regarding the mechanism of action of melatonin that will be critical for the use of melatonin as a treatment for circadian rhythm sleep disorders. Melatonin supplements have been reported to be an effective treatment for circadian rhythm sleep disorders, including shift work dyssomnia, jet-lag, delayed sleep phase syndrome, and sleep disruption suffered by many blind individuals. However, the mechanism(s) by which melatonin affects the timing of sleep are not well- understood. This study will provide important information regarding the mechanism of action of melatonin that will be critical for the use of melatonin as a treatment for circadian rhythm sleep disorders
Keywords: Accidents; Acetamide, N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-; Address; Aeroseb-HC; Affect; Agonist; Arousal; Biological Clocks; Blood Plasma; Body Temperature; Cetacort; Chemotherapy-Hormones/Steroids; Circadian Rhythm Sleep Disorders; Circadian Rhythms; Clinical Trial Overviews; Clock, Biologic; Cort-Dome; Cortef; Cortenema; Cortisol; Cortispray; Cortril; Data Pooling; Data Poolings; Delayed Sleep Phase Syndrome; Dermacort; Development; Disease; Disorder; Disturbed Nyctohemeral Rhythm; Diurnal Rhythm; Dose; Eldecort; Endocrine Gland Secretion; Epiphysis Cerebri; Evidence based treatment; Exposure to; Eye; Eyeball; Food Supplements; Gastrointestinal Diseases; Gastrointestinal Diseases and Manifestations; General Population; General Public; Health; Hormones; Hour; Human; Human, General; Hydrocortisone; Hydrocortone; Hytone; Individual; Insomnia; Insomnia Disorder; Investigators; Jet Lag; Jet Lag Syndrome; Jetlag; Jetlag Syndrome; Laboratories; Lead; Light; Maintenance; Maintenances; Man (Taxonomy); Man, Modern; Measures; Melatonin; Meta-Analyses; Meta-Analysis; Methods; Modeling; North America; Nutracort; Nyctohemeral Rhythm; Outcome; PBO; Pathway interactions; Pb element; Performance; Phase; Phase response curves; Photoradiation; Physiologic; Physiological; Pineal Body; Pineal gland; Placebos; Plasma; Pregn-4-ene-3, 20-dione, 11, 17, 21-trihydroxy-, (11beta)-; Pressure; Pressure- physical agent; Primary Insomnia; Process; Proctocort; Property; Property, LOINC Axis 2; Randomized Controlled Trials; Reporting; Research Personnel; Researchers; Reticuloendothelial System, Serum, Plasma; SCHED; Safety; Schedule; Serum, Plasma; Sham Treatment; Simulate; Sleep; Sleep Disorders; Sleep Disorders, Circadian Rhythm; Sleep Wake Cycle; Sleep-Wake Cycle Disorders; Sleep-Wake Schedule Disorders; Sleeplessness; Structure of suprachiasmatic nucleus; Supplementation; Suprachiasmatic Nucleus; System; System, LOINC Axis 4; Testing; Therapeutic Hormone; Therapeutic Hydrocortisone; Time; Time Zone Change Syndrome; Time Zone Syndrome; Transient Insomnia; Travel; Treatment Period; Twenty-Four Hour Rhythm; United States; Visually Impaired Persons; Wakefulness; Wakefulnesses; alertness; awake; base; blind individual; blind people; blind person; body clock; cardiac disease risk; cardiac disorder risk; circadian; circadian clock; circadian pacemaker; circadian process; cost; daily biorhythm; day shift; disease/disorder; diurnal variation; effective therapy; experience; gastrointestinal disorder; heart disease risk; heart disorder risk; heavy metal Pb; heavy metal lead; improved; internal clock; night shift; night work; onset of sleep; pathway; pineal organ; pressure; randomized controlled study; sham therapy; shift work; sleep onset; sleep problem; suprachiasmatic nucleus; systematic review; treatment days; treatment duration; visually impaired people
Relevance: Melatonin supplements have been reported to be an effective treatment for circadian rhythm sleep disorders, including shift work dyssomnia, jet-lag, delayed sleep phase syndrome, and sleep disruption suffered by many blind individuals. However, the mechanism(s) by which melatonin affects the timing of sleep are not well- understood. This study will provide important information regarding the mechanism of action of melatonin that will be critical for the use of melatonin as a treatment for circadian rhythm sleep disorders
Project start date: 2009-05-01
Project end date: 2014-04-30
Budget start date: 1-MAY-2010
Budget end date: 30-APR-2011
PFA/PA: PA-07-070
5R01HL093279-02 (2010): $317500
1R01HL093279-01A1 (2009): $316458
Bright Light Treatment Of Shift Rotation Insomnia
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5R01HL052992-10 from National Heart, Lung, And Blood Institute IRG: SOH
Abstract: Night and rotating shift work schedules induce misalignment between the phase of the circadian pacemaker and the work/sleep schedule, leading to excessive fatigue at work and disrupted daytime sleep in night workers. Also, night work often begins after more extended wakefulness, and hence greater homeostatic sleep pressure than daytime work. This combination leads to sleepiness, errors, and injuries on the night shift, as well as health problems. While treating subjects with bright light and a fixed morning sleep schedule results in rapid circadian adaptation to night work, there is currently a critical deficiency in understanding how different sleep schedules and light treatments combine to produce physiological and psychological adaptation to night work. High intensity bright light may be too expensive for some environments, and workers may be unable or unwilling to maintain fixed sleep schedules. Therefore, we plan to test the hypotheses 1) that 600 lux will be as effective in shifting the circadian phase of subjects into an appropriate sleep episode as 2500 lux; 2) subjects on an evening sleep schedule will perform better and be more alert than subjects on a morning sleep schedule; 3) that subjects whose melatonin secretion peak occurs during their sleep episode will perform better and be more alert than subjects whose melatonin secretion peak occurs during the work shift; 4) given a fixed sleep schedule, subjects whose melatonin secretion peak occurs during their sleep episode will sleep better than subjects whose melatonin secretion peak occurs during the work shift; 5) the melatonin phase of subjects who maintain a fixed sleep schedule in the laboratory will be shifted further than that of subjects who sleep ad lib at home. We propose an experiment to evaluate the effects of 3 different intensities of appropriately timed bright light during the night shift in combination with either AM, PM, or free sleep schedules on circadian phase, sleep alertness, and performance of subjects in a high-fidelity laboratory simulation of night work. We propose to measure circadian phase using salivary melatonin levels; alertness and performance via computerized assessments; and sleep via polysomnography. This work has major implications for the health and safety of shift workers.
Keywords: chronotherapy, human therapy evaluation, phototherapy, psychophysiology, sleep disorder, visible light, circadian rhythm, melatonin, performance, sleep, wakefulness, clinical research, electroencephalography, human subject
Project start date: 1994-07-10
Project end date: 2008-05-31
5R01HL052992-10 (2005): $394405
5R01HL052992-09 (2004): $382996
Sponsored Links Excellgen http://Excellgen.com
5R01HL052992-08 (2003): $371915
5R01HL052992-07 (2002): $360463
2R01HL052992-06A1 (2001): $369528
CIRCADIAN ADAPTATION TO NIGHT WORK IN OLDER PEOPLE
Charles A Czeisler, Professor Of Medicine
Brigham And Women´s Hospital
research Administration
boston, Ma 02115
Grant 5R01HL065207-03 from National Heart, Lung, And Blood Institute IRG: ZOH1
Abstract: Night and rotating shift work schedules induce misalignment between the phase of the circadian pacemaker and the work/sleep schedule, leading to excessive fatigue at work and disrupted daytime sleep in night workers. Also, night work often begins after more extended wakefulness than daytime work. This combination leads to sleepiness, errors, and injuries on the night shift, as well as health problems. These effects are worse for older workers. While we have shown that treating young subjects with bright light and a fixed morning sleep schedule results in rapid circadian adaptation to night work, preliminary studies indicate that this strategy will be ineffective for older people, whose sleep is more sensitive to incomplete circadian adaptation to delayed sleep schedules. Given the increasing median age of the workforce, it is critical to develop shift work effective countermeasures for the older worker. We hypothesize that phase advancing the sleep episode and circadian rhythm will be a more effective strategy in older workers. We propose three testable hypotheses that 1) older subjects who work 3 successive night shifts and sleep ad lib will suffer from misalignment between their work/sleep schedule and their circadian phase, disrupted daytime sleep, and degraded night shift performance relative to the day shift; 2) in older subjects who are scheduled to sleep in the morning after their night shifts, working 3 successive nights in bright light during the beginning of the night shift will improve alignment between the work/sleep cycle and the circadian melatonin rhythm compared to working 3 successive night shifts in standard room light, without the corresponding improvement in sleep and night shift performance that has been observed in young subjects; and, 3) in older subjects who are scheduled to sleep in the evening before their night shifts, working 3 successive nights in bright light during the late hours of the night shift will improve alignment between the work/sleep cycle and the circadian melatonin rhythm compared to working 3 successive night shifts in standard room light, with a corresponding improvement in sleep and night shift performance. We propose an experiment to evaluate the effects of two regimens combining bright light treatment and scheduled sleep on circadian melatonin rhythms, sleep, performance in older individuals in a laboratory simulation of night work. We propose to measure activity and light exposure with ambulatory devices, circadian phase using salivary melatonin levels, sleep via polysomnography, and performance by computerized tests. This work has major implications for the health and safety of older shift workers
Keywords: aging, circadian rhythm, occupation, occupational health /safety, photobiology age difference, job performance, melatonin, occupational psychology, sleep, work site clinical research, electrocardiography, electroencephalography, human middle age (35-64), human old age (65+), human subject, questionnaire
Project start date: 1999-09-30
Project end date: 2002-08-31
5R01HL065207-03 (2001): $423750
5R01HL065207-02 (2000): $423750
1R01HL065207-01 (1999): $423750
BRIGHT LIGHT TREATMENT OF SHIFT ROTATION INSOMNIA
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5R01HL052992-05 from National Heart, Lung, And Blood Institute IRG: ZRG7
Abstract: More than one-third of working men and one-quarter of working women in the U. S. report being exposed to a variable schedule that includes both day and night work. Of these, approximately 7.3 million must regularly work overnight, either on permanent night shifts or rotations between day, evening, and night shifts, requiring them to forego nocturnal sleep and attempt to sleep during the day. Despite this nocturnal deprivation of sleep, these workers typically experience daytime insomnia, leading to diminished alertness and cognitive performance and increased sleep tendency during waking hours at night. In fact, 55 percent of night shift workers report nodding off or falling asleep at work at least once per week, with more than 30 percent reporting that such incidents occur more than three times per week. Recent research has demonstrated that properly timed exposure to bright light and darkness can rapidly reset the human circadian pacemaker that-controls the timing of the sleep-wake cycle, enabling the circadian pacemakers of individuals working at night to fully adapt to their desired schedules within 2-3 days. On the basis of these results, four testable hypotheses are proposed (l) that bright light can rapidly shift the endogenous circadian rhythms of plasma melatonin secretion of individuals working at night, such that their circadian timing system remains adapted to their inverted sleep-wake schedule; (2) that bright light can increase sleep efficiency, and reduce the number and duration of awakenings during the daytime sleep of individuals working at night; (3) that bright light can reduce the frequency of involuntary microsleep episodes and decrease sleep propensity during scheduled wakefulness at night; and (4) that bright light can improve the alertness and cognitive performance of individuals working at night. An experiment is proposed to evaluate the impact of bright light treatment on the daytime sleep and nocturnal cognitive performance of individuals during a combined laboratory- and field-based simulation of a complete, 3- month shift rotation. Subjects exposed to an appropriate schedule of bright light while working in the laboratory will be compared to a control group of subjects without bright light exposure. Sleep, activity, and light exposure will be monitored with ambulatory recording devices, circadian phase will be assessed from serum melatonin levels, and cognitive performance will be evaluated with a computer-administered battery of tests. This work has significant implications for shiftworker health and population safety. Shiftwork is associated with cardiovascular disease, depression, increased drug use, and digestive disorders. Many catastrophic accidents (e.g., Exxon Valdez, Bhopal, Three-Mile Island, Chernobyl) have occurred during the night shift with fatigue identified as a contributor. An effective countermeasure to the personal and societal risks of shiftwork could substantially improve public health and safety.
Keywords: chronotherapy, human therapy evaluation, phototherapy, sleep disorder, visible light, attention, body temperature, circadian rhythm, cortisol, melatonin, psychomotor reaction time, short term memory, sleep, visual tracking, wakefulness, blood chemistry, electroencephalography, human subject, urinalysis
Project start date: 1994-07-10
Project end date: 2000-05-31
5R01HL052992-05 (1998): $567628
5R01HL052992-04 (1997): $548474
5R01HL052992-02 (1995): $512232
1R01HL052992-01 (1994): $449813
Sponsored Links Excellgen http://Excellgen.com
DISRUPTED SLEEP IN THE ELDERLY--CIRCADIAN ETIOLOGY
Charles A Czeisler, Professor Of Medicine
Brigham And Women´s Hospital
research Administration
boston, Ma 02115
Grant 5R01AG006072-13 from National Institute On Aging IRG: HUD
Abstract: More than one-quarter of older people complain that they wake up frequently during the latter part of the night, with 15 percent reporting that they cannot sleep past 5 AM. Prior results show that early morning awakening also occurs in most healthy older people who have no sleep complaint, who are not depressed and who do not exhibit any evidence of age-related shortening of intrinsic circadian period. Studies funded by the current grant suggest that this age-related increase in sleep interruptions during the latter part of the night cannot be explained by an age-related change in circadian photic resetting sensitivity. Based on recent analyses, the investigators have found 1) an age-related narrowing of the circadian phase interval over which the latter part of sleep can remain consolidated, leading to a marked age-related increase in the susceptibility of sleep to misalignment of circadian phase; and 2) an age-related increase in the variability of entrained circadian phase. It is hypothesized that these age-related circadian changes may account for a substantial component of the high prevalence of disrupted sleep and early morning awakening observed among older people. This implies that in older people, achieving and maintaining a precise (and narrow) relationship between circadian phase and the timing of sleep is crucial to attain sleep consolidation. The investigators´ findings on the effect of light on human rhythms suggest that the optimum phase relationship between sleep and endogenous circadian rhythms in older people can be achieved by appropriately timed exposure to a novel light exposure pattern of brief, intermittent bright light pulses. Four testable hypotheses are proposed (I) the phase of the melatonin and temperature rhythms and wake-time will occur at an earlier hour for older than for young adults living on self-selected sleep-wake schedules at home; (II) under base-line conditions on those self-selected schedules, wakefulness in the final third of the night will be higher for older subjects; (III) four brief exposures to evening bright light each day will be sufficient to establish and maintain entrainment of the sleep-wake cycle at an optimal circadian phase, resulting in reduced wakefulness in the final third of the night and enhanced daytime alertness; and (IV) a similar pattern of bright light exposure in the morning will not improve circadian phase misalignment
Keywords: aging, circadian rhythm, disease /disorder etiology, sleep age difference, cognition, cortisol, emotion, human old age (65+), melatonin, memory, photostimulus, psychomotor function, temperature, wakefulness, young adult human (19-34) clinical research, human subject
Project start date: 1985-07-01
Project end date: 2003-03-31
5R01AG006072-13 (2000): $441036
5R01AG006072-12 (1999): $428930
2R01AG006072-11A1 (1998): $417180
CIRCADIAN SLEEP--WAKE REGULATION IN OLDER PEOPLE
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5P01AG009975-100001 from National Institute On Aging
Abstract: More than half of individuals over 65 report at least some disturbance of their sleep, especially the inability to sustain consolidate sleep throughout the night. Evidence gathered during the initial period of this project suggests strongly that age-related sleep maintenance insomnia may be mediated by a misalignment between habitual sleep times and the phase of the circadian timing system. Additionally, our preliminary results of an NIA-funded double-blind, randomized, placebo- controlled clinical trial indicated that a group of young subjects on a forced desynchrony protocol who were administered a physiologic dose of melatonin (0.3 mg) had significantly greater sleep efficiency than a comparable group administered placebo. We propose to compare results in healthy people with those from the adults in order to quantify age- related changes in the impact of circadian phase on sleep, to quantify age-related changes in the ability to tolerate small degrees of misalignment between sleep and circadian phase, and to quantify the hypnotic efficacy of a physiologic (0.3 mg) and a pharmacologic (5.0 mg) dose of melatonin in older subjects. The proposed investigation is designed to test the following hypotheses 1) that sleep efficiency, waking alertness and neurobehavioral performance will vary markedly with circadian phase when older subjects are scheduled on a 20-hour forced desynchrony protocol, and that the sleep efficiency of healthy older people will be significantly worse at all circadian phases as compared with that of healthy young adults; 2) that the rising phase of the wake propensity rhythm will be internally phase-advanced with respect to the endogenous circadian temperature and melatonin rhythms in older subjects; 3) that pre-sleep administration of melatonin (0.3 mg ir 5.0 mg) during the forced desynchrony protocol will result in improved sleep efficiency as compared to pre-sleep administration of placebo. We propose to test these hypotheses in health and older males and female whose sleep-wake cycle is scheduled to a 20-hour day (i.e., 13.33 h wake followed by 6.67 h sleep opportunity) on a forced desynchrony protocol. Oral melatonin (0.3 mg or 5.0 mg) or placebo will be administered 30 minutes before lights out. Polysomnographic sleep recording and quantitative analyses of EEG will be used to describe age-related changes in circadian sleep regulation and understand the effects of melatonin on sleep in older persons. The results of this project should further our understanding of age- related sleep disturbance and its potential dependence on circadian misalignment. Furthermore, this project will test the efficacy of two doses of melatonin as a potential therapeutic treatment of insomnia in older people.
Keywords: circadian rhythm, hormone therapy, human therapy evaluation, melatonin, sleep, sleep disorder, wakefulness, REM sleep, age difference, aging, attention, clinical trial, dosage, neuropsychology, pharmacokinetics, psychomotor function, sedative /hypnotic, blood chemistry, electrocardiography, human old age (65+), human subject, polysomnography, psychological test
CIRCADIAN AND HOMEOSTATIC SLEEP REGULATION OLDER PEOPLE
Charles A Czeisler, Professor Of Medicine
Brigham And Women s Hospital Research Administration Boston, Ma 02115
Grant 5P01AG009975-120001 from National Institute On Aging IRG: ZAG1
Abstract: More than a third of adults ages 55 and older report sleeping less than 7h per night on a regular basis, with nearly 15% sleeping <6h per night. The consequences of acute sleep deprivation are well understood, but far less is known about the effects chronic insufficient sleep, particularly in older people. Evidence gathered during the previous grant periods strongly suggests that the sleep quality of older people is extremely vulnerable to a misalignment between the timing of sleep and the phase of the circadian timing system suggests that older people will be less able than young adults to obtain needed recovery sleep following acute sleep loss. There is also compelling evidence that the interaction between the two major sleep regulatory processes, the circadian and the sleep-wake homeostat, changes with age. We propose a study that will assess the effects of chronic sleep restriction in young and older adults, using a study design that will allow us to quantify age-related differences in the impact of circadian and sleep-dependent influences on sleep. The proposed investigation is designed to test the following hypotheses 1) that notwithstanding the increased homeostatic sleep pressure induced by chronic sleep restriction, sleep will be significantly more disrupted when it is scheduled at adverse circadian phases in older as compared with young adults; 2) that under conditions of chronic sleep restriction, slow-wave activity during sleep will be increased at all circadian phases in both young and older subjects; 3) that the circadian rhythm of REM sleep will be preserved across 4 weeks of chronic sleep restriction in young and older subjects, and that it will be preserved in older subjects at the expense of other sleep stages, including slow-wave sleep; and 4) that unlike the sleep of young subjects, during sleep extension following 4 weeks of chronic sleep restriction, the sleep of older subjects will not show rapid recovery as measured by the duration and intensity of slow-wave sleep, sleep efficiency, and number of awakenings. We propose to test these hypotheses in healthy young and older men and women whose sleep-wake cycle is scheduled to a 28-h day under conditions of chronic sleep restriction (i.e., 22.17 h wake followed by 5.83 h sleep opportunity) on a forced desynchrony protocol across 4 weeks. Polysomnographic sleep recording and quantitative analysis of EEC will be used to describe age-related changes in circadian sleep regulation and to understand the effects of chronic sleep restriction on sleep in older persons. The results of this project will provide important information on the effects of chronic insufficient sleep in older people, a condition which a significant portion of the older population experiences on a regular basis, and an area of investigation in which few laboratory-based investigations have been conducted.
Keywords: aging, circadian rhythm, homeostasis, sleep, sleep deprivation, sleep disorder, REM sleep, age difference, wakefulness, electroencephalography, human middle age (35-64), human old age (65+), human subject, polysomnography, young adult human (21-34)
CIRCADIAN AND HOMEOSTATIC SLEEP REGULATION IN OLDER PEOPLE
Charles A Czeisler, Professor Of Sleep Medicine
Brigham And Women´s Hospital, Research Administration, Boston, Ma 02115
Abstract: More than a third of adults ages 55 and older report sleeping less than 7h per night on a regular basis, with nearly 15% sleeping <6h per night. The consequences of acute sleep deprivation are well understood, but far less is known about the effects chronic insufficient sleep, particularly in older people. Evidence gathered during the previous grant periods strongly suggests that the sleep quality of older people is extremely vulnerable to a misalignment between the timing of sleep and the phase of the circadian timing system suggests that older people will be less able than young adults to obtain needed recovery sleep following acute sleep loss. There is also compelling evidence that the interaction between the two major sleep regulatory processes, the circadian and the sleep-wake homeostat, changes with age. We propose a study that will assess the effects of chronic sleep restriction in young and older adults, using a study design that will allow us to quantify age-related differences in the impact of circadian and sleep-dependent influences on sleep. The proposed investigation is designed to test the following hypotheses 1) that notwithstanding the increased homeostatic sleep pressure induced by chronic sleep restriction, sleep will be significantly more disrupted when it is scheduled at adverse circadian phases in older as compared with young adults; 2) that under conditions of chronic sleep restriction, slow-wave activity during sleep will be increased at all circadian phases in both young and older subjects; 3) that the circadian rhythm of REM sleep will be preserved across 4 weeks of chronic sleep restriction in young and older subjects, and that it will be preserved in older subjects at the expense of other sleep stages, including slow-wave sleep; and 4) that unlike the sleep of young subjects, during sleep extension following 4 weeks of chronic sleep restriction, the sleep of older subjects will not show rapid recovery as measured by the duration and intensity of slow-wave sleep, sleep efficiency, and number of awakenings. We propose to test these hypotheses in healthy young and older men and women whose sleep-wake cycle is scheduled to a 28-h day under conditions of chronic sleep restriction (i.e., 22.17 h wake followed by 5.83 h sleep opportunity) on a forced desynchrony protocol across 4 weeks. Polysomnographic sleep recording and quantitative analysis of EEC will be used to describe age-related changes in circadian sleep regulation and to understand the effects of chronic sleep restriction on sleep in older persons. The results of this project will provide important information on the effects of chronic insufficient sleep in older people, a condition which a significant portion of the older population experiences on a regular basis, and an area of investigation in which few laboratory-based investigations have been conducted
Keywords: 21+ years old; Acute; Adult; Age; Aged 65 and Over; Aging; Area; Chronic; Circadian Rhythms; Delta Wave; Delta Wave sleep; Dependence; Diurnal Rhythm; EEG; Elderly; Elderly, over 65; Electroencephalography; Female; Grant; Health; Human, Adult; Investigation; Laboratories; Monitoring, Sleep; Nyctohemeral Rhythm; Paradoxical Sleep; Phase; Polysomnography; Pressure; Pressure- physical agent; Protocol; Protocols documentation; QOL; Quality of life; REM Sleep; Recovery; Reporting; Research Design; Rhombencephalic Sleep; SCHED; Safety; Schedule; Senescence; Sleep; Sleep Deprivation; Sleep Stages; Sleep Wake Cycle; Sleep disturbances; Sleep, Fast-Wave; Sleep, REM; Slow-Wave Sleep; Somnography; Study Type; System; System, LOINC Axis 4; Testing; Time; Twenty-Four Hour Rhythm; adult human (21+); adult youth; advanced age; age dependent; age related; base; circadian; circadian process; daily biorhythm; diurnal variation; dreaming sleep; elders; geriatric; late life; later life; male; older adult; older person; polysomnographic; pressure; rapid eye movement sleep; senescent; senior citizen; sleep control; sleep measurement; sleep polysomnography; sleep regulation; study design; young adult
Budget start date: 1-JUL-2010
Budget end date: 30-JUN-2011
5P01AG009975-15_0001 (2010): $314705
3P01AG009975-14S3_0001 (2009): $27642
5P01AG009975-14_0001 (2009): $313868
CIRCADIAN AND HOMEOSTATIC SLEEP REGULATION OLDER PEOPLE
Charles A Czeisler, Professor Of Medicine
Brigham And Women´s Hospital
research Administration
boston, Ma 02115
Grant 5P01AG009975-130001 from National Institute On Aging IRG: ZAG1
Abstract: More than a third of adults ages 55 and older report sleeping less than 7h per night on a regular basis, with nearly 15% sleeping <6h per night. The consequences of acute sleep deprivation are well understood, but far less is known about the effects chronic insufficient sleep, particularly in older people. Evidence gathered during the previous grant periods strongly suggests that the sleep quality of older people is extremely vulnerable to a misalignment between the timing of sleep and the phase of the circadian timing system suggests that older people will be less able than young adults to obtain needed recovery sleep following acute sleep loss. There is also compelling evidence that the interaction between the two major sleep regulatory processes, the circadian and the sleep-wake homeostat, changes with age. We propose a study that will assess the effects of chronic sleep restriction in young and older adults, using a study design that will allow us to quantify age-related differences in the impact of circadian and sleep-dependent influences on sleep. The proposed investigation is designed to test the following hypotheses 1) that notwithstanding the increased homeostatic sleep pressure induced by chronic sleep restriction, sleep will be significantly more disrupted when it is scheduled at adverse circadian phases in older as compared with young adults; 2) that under conditions of chronic sleep restriction, slow-wave activity during sleep will be increased at all circadian phases in both young and older subjects; 3) that the circadian rhythm of REM sleep will be preserved across 4 weeks of chronic sleep restriction in young and older subjects, and that it will be preserved in older subjects at the expense of other sleep stages, including slow-wave sleep; and 4) that unlike the sleep of young subjects, during sleep extension following 4 weeks of chronic sleep restriction, the sleep of older subjects will not show rapid recovery as measured by the duration and intensity of slow-wave sleep, sleep efficiency, and number of awakenings. We propose to test these hypotheses in healthy young and older men and women whose sleep-wake cycle is scheduled to a 28-h day under conditions of chronic sleep restriction (i.e., 22.17 h wake followed by 5.83 h sleep opportunity) on a forced desynchrony protocol across 4 weeks. Polysomnographic sleep recording and quantitative analysis of EEC will be used to describe age-related changes in circadian sleep regulation and to understand the effects of chronic sleep restriction on sleep in older persons. The results of this project will provide important information on the effects of chronic insufficient sleep in older people, a condition which a significant portion of the older population experiences on a regular basis, and an area of investigation in which few laboratory-based investigations have been conducted
Keywords: aging, circadian rhythm, homeostasis, sleep, sleep deprivation, sleep disorder REM sleep, age difference, wakefulness electroencephalography, human middle age (35-64), human old age (65+), human subject, polysomnography, young adult human (21-34)
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