Author Interviews, Heart Disease, Sleep Disorders / 11.01.2016

MedicalResearch.com Interview with: Sunil Sharma MD, FAASM Associate Professor of Medicine Director, Pulmonary Sleep Medicine Associate Director, Jefferson Sleep Disorders Center Thomas Jefferson University and Hospitals Philadelphia, PA 19107 Medical Research: What is the background for this study? Dr. Sharma: Congestive heart failure (CHF) is the most common cause of hospital admission and readmissions in United States. More health care dollars are spent on CHF than any other diagnosis. A large chunk of this cost is due to hospital admission.  An estimated 50% of the CHF patients are readmitted within 6 months of discharge. The recent Protection Affordable Care Act (ACA) imposes penalties on hospitals for readmissions within first 30-days. It is therefore imperative to find ways to impact the natural history of the disease. Sleep disordered breathing is a common disorder associated with CHF. It is estimated that up to 70% of the patient with CHF may have SDB. Studies have shown that untreated SDB can worsen CHF and treatment of Sleep disordered breathing has been shown to improve heart function (ejection fraction).  (more…)
Author Interviews, Dermatology, JAMA, Melatonin, Pediatrics, Sleep Disorders / 23.11.2015

MedicalResearch.com Interview with: Prof. Bor-Luen Chiang Vice Superintendent, National Taiwan University Hospital Professor of Graduate Institute of Clinical Medicine and Pediatrics National Taiwan University Attending Physician, Department of Medical research National Taiwan University Hospital and Yung-Sen Chang, MD MPH Attending physician, Department of Pediatrics, Taipei City Hospital Renai Br. Adjunct Attending Physician, Department of Pediatrics National Taiwan University Children’s Hospital Adjunct Instructor, School of Medicine, National Yang-Ming University Medical Research: What is the background for this study? Prof. Chang: Sleep disturbance is a common disorder in the children with atopic dermatitis (AD) (reported in 47 to 60%), but no effective way of managing this problem had been established. In our preceding study, we found that lower nocturnal melatonin level was significantly associated with sleep disturbance in the patients with AD. Melatonin is a hormone secreted by the pineal gland which plays an important role in sleep regulation. In addition to sleep-inducing effects, melatonin also has anti-inflammatory and immunomodulatory properties which might be helpful for the management o fatopic dermatitis. Furthermore, melatonin has an excellent safety profile with minimal adverse effects, making it a good choice for children. Therefore, we aimed to evaluate whether melatonin is effective for improving the sleep problems and the dermatitis severity in children with atopic dermatitis. Medical Research: What are the main findings? Prof. Chang: From our double-blind, placebo-controlled crossover study, we found that after melatonin treatment, the sleep onset latency shortened by 21.4 minutes compared with placebo (from a mean of 44.9 minutes to 21.6 minutes). The Scoring Atopic Dermatitis Index (higher scores representing more severe dermatitis) also decreased by 9.9 compared with placebo (from a mean of 49.1 to 40.2). No adverse events were reported throughout the study. (more…)
Author Interviews, Gender Differences, Pediatrics, Sleep Disorders / 17.11.2015

MedicalResearch.com Interview with: Sabine Plancoulaine, MD, PhD Senior Researcher NSERM, UMR1153 Epidemiology and Statistics Sorbonne Paris Cité Research Center (CRESS), early Origin of the Child's Health And Development (ORCHAD) Team, Villejuif, France; and Paris Descartes University, Paris, France Medical Research: What is the background for this study? Dr. Plancoulaine: A decrease in children’s total sleep duration has been reported in the last decades, suggesting that more and more children are now in chronic sleep debt. There is now accumulating evidence that insufficient quantity and/or quality of sleep have a negative impact on children’s physical and mental health development, cognitive function, behaviour and academic success. Sleep disorders and short sleep duration in childhood have also been suggested as predictors of sleep disorders and short sleep duration in adolescence and adulthood. An increased risk of obesity has been shown among shorter sleeper children, especially boys.  Medical Research: What are the main findings? Dr. Plancoulaine: In our study we aimed at describing sleep duration in 3 years old children from a French pre-birth cohort (546 boys and 482 girls) and at investigating gender-specific factors associated with shorter sleep duration defined as <12h/24h. In our study, children aged 3 years slept on average 12hrs35 and 91% of them were napping. Parental presence when falling asleep (e.g. holding hands) was the only factor associated with shorter sleep duration in both gender and increased the risk by around 3 and 4 in boys and girls respectively. The other associated risk factors were more gender-specific. Among boys, each hour of TV viewing duration increased by 72% the risk of being a short sleeper and each additional standard deviation of BMI increased the risk by 31%. Among girls, adherence to a fruit and vegetables dietary pattern divided the risk of being short sleeper by 2 while being cared at home increased it by 2.5 folds. Other investigated factors were not associated (i.e. familial incomes, parental educational level, maternal age at birth, maternal pre-pregnancy BMI, maternal depression status (at birth and at 3y), gestational age, child’s birth rank, birth weight and physical activities at 3y, existence of night awakenings at 3y). (more…)
Author Interviews, Nutrition, Sleep Disorders / 05.11.2015

MedicalResearch.com Interview with: Mike C Parent, Ph.D. Assistant Professor, Counseling Psychology Texas Tech University Medical Research: What is the background for this study? What are the main findings? Dr. Parent: There is some research out there on energy drinks, and we know a few things about them. For instance, although the drinks are marketed as though they are for extreme sports athletes, most people who drink them are not athletes. It seems as though drinking them makes some men feel as though they are a part of that extreme sports culture, without even needing to participate in the sports, though. The other part was that, clinically, you would be amazed at how many young men present at student counseling centers and university medical centers with "sleep problems." Then, when you ask them about what they eat and drink during a day, it turns out that some of them are guzzling half a dozen of these drinks a day, or drinking them at night, totally unaware of the extremely high caffeine content. It's true that energy drinks can help people focus a but better or work out a bit harder--but that's because the active ingredient is caffeine. In this research, we aimed to marry together those two lines of work--how does wanting to be more masculine impact energy drink use, and what consequences might energy drink use have for something as basic as sleep hygiene? (more…)
Author Interviews / 20.09.2015

Miklos Z Molnar, MD, PhD, FEBTM, FERA, FASN Associate Professor of Medicine Division of Nephrology, Department of Medicine University of Tennessee Health Science Center Memphis, TN, 38163 MedicalResearch.com Interview with: Miklos Z Molnar, MD, PhD, FEBTM, FERA, FASN Associate Professor of Medicine Division of Nephrology, Department of Medicine University of Tennessee Health Science Center Memphis, TN, 38163 Medical Research: What is the background for this study? What are the main findings? Response: Restless legs syndrome is a common sleep disorder, but there is a paucity of large cohort studies examining the association of restless legs syndrome with clinical outcomes, including all-cause mortality, incident coronary heart disease, stroke and chronic kidney disease. From a nationally representative prospective cohort of over 3 million US veterans [93% male, median follow-up time of 8.1 years (interquartile range: 7.0–8.5years)] with baseline estimated glomerular filtration rate ≥60 mL/min/1.73 m2, a propensity-matched cohort of 7392 patients was created, and the association between incident restless legs syndrome and the following was examined:
  • (1) all-cause mortality;
  • (2) incident coronary heart disease;
  • (3) incident strokes; and
  • (4) incident chronic kidney disease defined as estimated glomerular filtration rate <60 mL/min/1.73 m2.
Compared with restless legs syndrome-negative patients, incident restless legs syndrome was associated with 88% higher mortality risk [hazard ratio and 95% confidence interval: 1.88 (1.70–2.08)], and almost four times higher risk of coronary heart disease and stroke [hazard ratio: 3.97 (3.26–4.84) and 3.89 (3.07–4.94), respectively]. The risk of incident chronic kidney disease was also significantly higher in incident restless legs syndrome patients [hazard ratio: 3.17 (2.74–3.66)] compared with restless legs syndrome-negative counterparts. These associations was independent from other confounders such as demographic data, comorbidities and other sleep disorders (sleep apnea and periodic limb movements in sleep). (more…)
Author Interviews, Pediatrics, Sleep Disorders / 15.09.2015

Ana C. Krieger, MD, MPH, FCCP, FAASM Medical Director, Center for Sleep Medicine Associate Clinical Professor Departments of Medicine, Neurology and Genetic Medicine Weill Cornell Medical College - Cornell University Associate Attending NewYork-Presbyterian Hospital Rockefeller University HospitalMedicalResearch.com Interview with: Ana C. Krieger, MD, MPH, FCCP, FAASM Medical Director, Center for Sleep Medicine Associate Clinical Professor Departments of Medicine, Neurology and Genetic Medicine Weill Cornell Medical College - Cornell University Associate Attending NewYork-Presbyterian Hospital Rockefeller University Hospital   Medical Research: What is the background for this study? What are the main findings? Dr. Krieger: For many years, sleep researchers have been concerned about sleep deprivation in adolescents. Our study shows that high school students have shorter sleep duration on the nights following the spring Daylight Saving Time adjustment. This sleep loss was associated with a decline in daytime vigilance and cognitive performance on the week following DST. (more…)
Author Interviews, Insomnia, Psychological Science / 12.09.2015

Markus Jansson-Fröjmark PhD Associate professor, clinical psychologist Department of Psychology Stockholm University MedicalResearch.com Interview with: Markus Jansson-Fröjmark PhD Associate professor, clinical psychologist Department of Psychology Stockholm University   Medical Research: What is the background for this study? What are the main findings? Response: There is ample evidence suggesting that how people regulate their emotions might influence several types of psychopathology, including anxiety and mood disorders. The purpose of our longitudinal investigation was therefore to examine the association between emotion regulation and how insomnia develops over time. Our main finding was that people whose ability to regulate their emotions had diminished were more likely to develop insomnia and that it was more likely to be persistent. A reduced ability to regulate emotions was associated with an 11% increased risk of developing a new bout of insomnia or reporting persistent insomnia. For anyone that has to deal with insomnia on a daily basis, they may find that is can effect a large part of their lives. Sleep is important for even, as it allows us all to function properly throughout the day. When it comes to Insomnia, there is medication out there that people can take that may help them with this issue. A popular method of treatment is through the use of medical marijuana. If this is something that you have been planning on trying, you would need to obtain your medical marijuana card in Cincinnati (if you live in this city) before you could start receiving product. Hopefully this will help with your insomnia and provide you with a better quality of sleep. (more…)
AHA Journals, Author Interviews, Heart Disease, Sleep Disorders / 12.09.2015

Chan-Won Kim, M.D. Clinical Associate Professor Center for Cohort Studies Kangbuk Samsun Hospital Sungkyunkwan University School of Medicine Seoul, South KoreaMedicalResearch.com Interview with: Chan-Won Kim, M.D. Clinical Associate Professor Center for Cohort Studies Kangbuk Samsun Hospital Sungkyunkwan University School of Medicine Seoul, South Korea Medical Research: What is the background for this study? Dr. Chan-Won Kim: In modern society, inadequate sleep either in quantity or in quality is a common problem and widely recognized as a potential determinant of adverse health outcomes including cardiovascular health. Very long or very short duration of sleep are associated with an increased risk for clinical cardiovascular events such as coronary heart disease and strokes. In these previous studies, however, it was possible that extreme sleep duration or poor sleep quality was a consequence of previous co-morbidities such as depression and obesity, and it was still unclear if these co-morbidities were really responsible for the effects of sleep disturbances. Therefore, we evaluated the association of sleep duration and quality with early markers of subclinical arterial disease in asymptomatic apparently healthy men and women. Medical Research: What are the main findings? Dr. Chan-Won Kim:  In our study, we found that sleep duration had a U-shaped association with two early markers of vascular disease. Both short and long sleep duration were associated with a greater amount of calcification in the coronary arteries, a very good measure of subclinical atherosclerosis that predicts the risk of a heart attack. We also found a similar pattern of association with arterial stiffness, a marker of vascular aging. For both markers, we found the lowers risk in study participants who reported 7 hours of sleep. In addition, poor subjective sleep quality was also associated with these markers of vascular disease. Few studies had explored these associations before, and they were inconsistent partly because of small sample sizes. Our research also indicates that these associations were present irrespective of traditional risk factors such as hypertension, hypercholesterolemia, or diabetes. (more…)
Author Interviews, Cancer Research, Melatonin, Sleep Disorders / 03.09.2015

MedicalResearch.com Interview with: Charlotte Lund Rasmussen Research Unit, Department of Palliative Medicine Bispebjerg Hospital, Copenhagen, Denmark Medical Research: What is the background for this study? What are the main findings? Response: We see that patients with advanced cancer often suffer from fatigue, pain, depression, insomnia and other symptoms, which can have a profound impact on quality of life. Melatonin is a neurohormone and its secretion is closely tied to the circadian rhythm making it a regulator of the sleep-cycle. Studies have shown that cancer patients have lower levels of melatonin than healthy controls, which may contribute to their fatigue and lowered quality of life. Furthermore, previous studies have found a possible effect of melatonin in cancer therapy, and non-clinical trials have shown melatonin to inhibit cell division in tumors. To our knowledge, no trials to date have investigated the effects of melatonin on fatigue. Given the role of melatonin in the sleep cycle, the lowered levels of melatonin noted among cancer patients, and results from previous studies, we wanted to investigate melatonin’s effect on fatigue among patients with advanced cancer. The primary objective of our study was to determine whether oral melatonin administered at night would reduce physical fatigue in patients with advanced cancer who were being treated in a palliative care facility. The effect of melatonin on other cancer-related symptoms including mental fatigue, insomnia, pain, emotional function, loss of appetite, and overall QoL were also investigated. In this trial we tested a dose of 20 mg of melatonin taken orally at night. However, melatonin did not improve physical fatigue in patients with advanced cancer. Furthermore, we were unable to identify improvements in any other cancer-related symptoms. (more…)
Author Interviews, Pediatrics, Sleep Disorders, Technology / 27.08.2015

Stephanie J. Crowley, Ph.D. Assistant Professor Biological Rhythms Research Laboratory Department of Behavioral Sciences Rush University Medical Center Chicago, IL 60612MedicalResearch.com Interview with: Stephanie J. Crowley, Ph.D. Assistant Professor Biological Rhythms Research Laboratory Department of Behavioral Sciences Rush University Medical Center Chicago, IL 60612 Medical Research: What is the background for this study? Dr. Crowley: Your readers may have seen recent reports by the American Academy of Pediatrics and the CDC about problems with early morning school bells for teens and the need to push school start times later.  These recent calls for later school start times come from data showing that biological processes make it challenging for a teen to get enough sleep and be rested for school when they have to wake up very early for school.  One of these biological processes is the circadian timing system, which is the approximate 24-hour brain clock that regulates the timing of sleep and wake.  During the teen years, the brain clock is shifted later making it more difficult for many teens to fall asleep early enough to get sufficient sleep on school nights. Medical Research: What are the main findings? Dr. Crowley: Melatonin suppression, as tested in this new study, is a good indication of how light affects the circadian system.  Our findings show that even a very small amount of light (similar to “romantic mood lighting”) in the evening suppressed melatonin levels in the middle-school-aged adolescents.  Because evening light “seen” by the brain clock shifts the clock later in time, the message is that biologically-driven later sleep times starts at this early age and needs to be considered when managing school and sleep schedules. (more…)
Alzheimer's - Dementia, Author Interviews, Sleep Disorders / 08.08.2015

Helene Benveniste, MD, PhD Professor of Anesthesiology and Radiology Vice Chair for Research, Department of Anesthesiology Stony Brook Medicine, Stony Brook NYMedicalResearch.com Interview with: Helene Benveniste, MD, PhD Professor of Anesthesiology and Radiology Vice Chair for Research, Department of Anesthesiology Stony Brook Medicine, Stony Brook NY Medical Research: What is the background for this study? Dr. Benveniste: The ‘glymphatic’ pathway is a part of the brain and is responsible for removal of waste products and excess fluid that built up especially during wakefulness. The concept was introduced by Nedergaard’s team in 2012 from University of Rochester. Importantly it has been shown to remove waste products such as soluble amyloid beta and tau protein which build up excessively in the brain of subjects afflicted with Alzheimer’s disease. The glymphatic system has been studied in detail in animal models (not yet humans) and actually is a brain-wide pathway which runs along (i.e. on the outside) of all vessels in the brain and connects to the space around the brain cells (referred to as the interstitial fluid (ISF) space). The outer part of the glymphatic network ‘tube’ is bordered by a certain type of brain cells so-called ‘astroglial’ cells which are arranged in a special way so that their endfeet cover >97% of the surface of all brain vessels. One can think of this as if the astroglial cell’s ‘endfeet’ are arranged as a donut shaped tube around all the vessels. On the astroglial endfeet there are special water channels (aquaporin-4 water channels) which are critical for how efficiently the glymphatic system can get rid of waste because it allows water to move fast through the brain tissue so as to ‘flush’ waste products out efficiently. The small gap between the astroglial endfeet also act like a ‘sieve’ so that only waste products of a certain size can access the entire pathway. Cerebrospinal fluid (CSF) circulates into the glymphatic pathway from the surface of the brain along the arteries which dives directly from the surface into the deeper part of the brain; and ultimately enters the space around the brain cells; and sweeps through it and thereby mixes with the interstitial fluid of the brain which contains waste products. The CSF-ISF mix with the waste products is then flushed out on the other ‘side’ along the veins and ultimately ends up in lymph vessels in the body and then in the blood. It has been shown that the glymphatic pathway removes brain waste more efficiently in a state of ‘unconsciousness’ e.g. sleep or anesthesia when compared to wakefulness. Given this intriguing finding i.e. that sleeps seems to affect the waste clearance from the brain we thought that the next to look at was sleeping positions. We did these studies in anesthetized rodents. (more…)
Author Interviews, JCEM, Sleep Disorders / 29.07.2015

Jonathan Cedernaes M.D., Ph.D. Department of Neuroscience Uppsala University SwedenMedicalResearch.com Interview with: Jonathan Cedernaes M.D., Ph.D. Department of Neuroscience Uppsala University Sweden Medical Research: What is the background for this study? What are the main findings? Dr. Cedernaes: Previous studies have demonstrated that experimental sleep loss and simulated shift work (i.e. misalignment of circadian rhythms) reduces energy expenditure and insulin sensitivity, providing links to why sleep loss may increase the risk of e.g. type-2 diabetes and obesity. Such phenotypes have also been observed in animals in which clock genes are ablated. Clock genes regulate the circadian rhythms of all cells and variants in these have also been associated with increased risk of obesity, insulin resistance and type-2 diabetes in humans. Almost no study has however investigated whether overnight wakefulness - mimicking a situation which recurrently occurs in shift work - can affect the expression of such clock genes in metabolically important tissues, i.e. adipose tissue and skeletal muscle, in humans. Such gene expression changes may both acutely and more long-term be regulated by changes in methylation, i.e. an epigenetic change, which have been found in blood of e.g. shift workers and in e.g. adipose tissue of type-2 diabetic subjects. However, whether sleep loss can lead to epigenetic changes has been unknown, and therefore also whether this could affect genes important for metabolism, such as the core clock genes which are essential for orchestrating and synchronizing downstream metabolic processes according to our circadian rhythms. With this background in mind, I and associate professor Christian Benedict set out to conduct a study to investigate how one night of sleep loss altered gene transcription and methylation of core clock genes in adipose tissue and skeletal muscle, and whether this would be reflected at the systemic level by an impaired glucose tolerance test in healthy young individuals. For the study, we had 15 participants undergo two almost 2-day long sessions in our lab, with the first night of each session serving as a baseline or habituation night, with a normal sleep period. On the second night, in random order, participants slept a full night (8.5 hours) in one session, and were kept awake the entire night while being bed-restricted in the other of two sessions. After each of these conditions, we took biopsies in the fasting condition from the subcutaneous adipose tissue and the skeletal muscle. In collaboration with researchers from the Karolinska Institute, Gothenburg University and the German Institute of Human Nutrition, we were able to observe transcriptional repression of clock genes in the muscle, but not in the adipose tissue following sleep loss compared with normal sleep. Instead, we found methylation of regulatory elements of clock genes to be increased in the adipose tissue but not the skeletal muscle following sleep loss compared with normal sleep. Finally, we observed that participants had an impaired glucose tolerance test when they had been kept awake as compared with their response after sleep. (more…)
Author Interviews, Brain Injury, Pediatrics, Sleep Disorders / 14.06.2015

MedicalResearch.com Interview with: Kimberly Allen PhD, RN Assistant Professor Center dr-kimberly-allenfor Narcolepsy, Sleep and Health Research Department Women Children and Family Health Science Chicago, IL 60612 Medical Research: What is the background for this study? Dr. Allen: Pediatric traumatic brain injuries (TBI) are a leading cause of morbidity and mortality worldwide.Each year in the United States over 1Ž2 million children are admitted to the hospital for traumatic brain injuries (TBIs). Depending on the severity of the injury and how the individual child responds to the primary injury, a range of medical care may be necessary from an overnight hospital admission for observation to admission in the intensive care unit (ICU) and inpatient rehabilitation facility to re-teach and help to recover skills children once knew. The short- and long-term consequences of traumatic brain injuries include: motor and sensory impairments; cognitive, emotional, psychosocial impairments; headaches, and sleep disruptions. Medical Research: What are the main findings? Dr. Allen: The main finding from this pilot study with two groups with 15 children in each group: one of children with traumatic brain injuries and one of typically, developing healthy children was that children with traumatic brain injuries have significantly more daytime sleepiness and worse sleep quality compared to the control group. Additionally, children with TBI also had lower overall  functional scores (e.g, school, social) compared to the controlled children. All of the surveys were completed by the child’s parent. (more…)
Annals Internal Medicine, Author Interviews, Insomnia, Psychological Science / 10.06.2015

MedicalResearch.com Interview with: Dr David Cunnington Sleep Physician & Director Melbourne Sleep Disorders Centre East Melbourne Australia Medical Research: What is the background for this study? What are the main findings? Response: Insomnia is a very common problem with 15-20% of adults having chronic insomnia, that is, trouble getting to sleep or staying asleep most days for  3 months or more. The most commonly used treatment is sleeping pills or hypnotics, however, they don’t address the underlying disorder, and come with potential side effects. Also, sleeping tablets just mask the symptoms, and as soon as tablets are stopped, symptoms recur. People with chronic insomnia think and behave differently around sleep, which perpetuates their symptoms. The key to improving symptoms in the long run is addressing thoughts and behaviours around sleep, which is what cognitive behaviour therapy does. Our study showed that cognitive behaviour therapy reduced the time taken to get to sleep by 20 minutes and reduced the amount of time spent awake after falling asleep by nearly 30 minutes. These effects were maintained out to 12 months after treatment. These reductions in time taken to get to sleep and time spent awake are similar to those reported in clinical trials of hypnotics.  (more…)
Author Interviews, Baylor College of Medicine Houston, Sleep Disorders, Urology / 18.05.2015

MedicalResearch.com Interview with: Alexander W. Pastuszak, MD, PhD Male Reproductive Medicine and Surgery Scott Department of Urology Jason Malcolm Scovell Medical Student, Ofc SA-BCM Students Baylor College of Medicine Houston, TX Medical Research: What is the background for this study? What are the main findings? Response: Sleep quality is an important component of overall health, and can both exacerbate health issues and be impaired by health problems. Shift workers, primarily those who do not work standard daylight shifts, are prone to sleep problems, a significant concern in light of the fact that up to 25% of the U.S. workforce is comprised of shift workers. As men age, the prevalence of Lower Urinary Tract Symptoms (LUTS), which include urgency, frequency, waking up at night to urinate, and difficulties with urination, increases.  Unsurprisingly, men with LUTS report poor sleep in part due to awakening repeatedly during the night. We studied a group of male shift workers, who we believe to be an ‘at-risk’ population, and found that not only do the men who report worse sleep quality have worse Lower Urinary Tract Symptoms, but also men who report difficulty falling asleep have more severe LUTS than those who do not. This latter point is significant, given that most men with LUTS can fall asleep without difficulty, but then awaken repeatedly throughout the night, and suggests that sleep difficulties in this population may be resulting in Lower Urinary Tract Symptoms rather than LUTS exclusively resulting in sleep difficulties. (more…)
Author Interviews, Sleep Disorders / 10.05.2015

Hans P.A. Van Dongen, Ph.D. Director, Sleep and Performance Research Center Research Professor, College of Medical Sciences Washington State University Spokane, Spokane, WA MedicalResearch.com Interview with: Hans P.A. Van Dongen, Ph.D. Director, Sleep and Performance Research Center Research Professor, College of Medical Sciences Washington State University Spokane, Spokane, WA On behalf of the authors: Paul Whitney PhD, John Hinson PhD, Melinda Jackson PhD, Hans Van Dongen PhD MedicalResearch: What is the background for this study? What are the main findings? Research: Our main interest is in better understanding why people sometimes are able to manage perfectly well with sleep loss, while at other times sleep loss can have profoundly negative effects. We found that sleep deprivation reduces the effectiveness of signals used to tell when you are right or wrong, an effect we labeled feedback blunting. Subjects in the study performed a decision making task that was simple but required feedback, i.e., a signal indicating the response was correct or incorrect, to perform correctly. We found that people who were sleep deprived were no longer able to use the feedback information to make correct responses. And when people had to adapt to unexpected changes in when to respond, sleep deprived people were completely unable to adapt to these changing circumstances. The finding of feedback blunting in this study indicates that people who are sleep deprived not only have trouble sustaining attention to details in the environment (a well established effect of sleep loss), they also have trouble changing the focus of attention to deal with changing circumstances. An interesting paradox in the research literature has been that people have been shown in many circumstances to perform complex tasks at a very high level while sleep deprived. Yet, we know from real-world experience that sleep deprived people can make catastrophic, life-threatening decisions that they would never have made if they were well rested. The current study is the first to shed light on this issue. It showed that sleep deprived people who get feedback, telling them that their actions are not effective, are less capable of changing their behavior. The study is part of a line of research in which we are trying to identify how sleep loss changes specific components of cognition, and how these changes may lead to serious problems in everyday life activities. Being able to study and understand these effects of sleep deprivation under controlled conditions is an important step toward preventing human error under real world conditions. (more…)
Author Interviews, Psychological Science, Sleep Disorders / 01.05.2015

Jaime L. Tartar PhD Behavioral Neuroscience Major Chair Division of Social and Behavioral Sciences Nova Southeastern University Fort Lauderdale, FloridaMedicalResearch.com Interview with: Jaime L. Tartar PhD Behavioral Neuroscience Major Chair Division of Social and Behavioral Sciences Nova Southeastern University Fort Lauderdale, Florida Medical Research: What is the background for this study? What are the main findings? Dr. Tartar: We set out to understand how poor sleep quality can influence emotion processing. Our rationale for this study was that although sleep perturbations are known to impair cognitive performance, it is not currently clear how poor sleep alters emotion processes. However, given that poor sleep quality is closely associated with the development of mood disorders, it is important to understand how sleep quality affects emotional functioning. We specifically examined the possibility that poor sleep quality creates a cognitive bias in memory and interpretation for emotionally negative stimuli. This would result in maladaptive emotional experiences- for example, through enhanced memory for emotionally negative events (which is also a common characteristic of depression). The idea that negative cognitive bias occurs with poor sleep quality is also consistent with the finding that sleep loss increases sensitivity to emotional stimuli as well as increases undesirable mood states like irritability, anger, and hostility.  It is particularly noteworthy that sleep perturbations result in increased emotionality since sleep perturbations are shown to result in a decrease in non-emotional cognitive processes (attention and memory).  In order to clarify the role of sleep quality on emotion processing, we tested the relationship between sleep quality and a negative cognitive bias through the use of an emotional memory task.  We also aimed to contrast these findings with performance on a non-emotional attention task since sleep impairments have previously been shown to cause impairments in (non-emotional) sustained attention. An interesting feature of the study was that we also accounted for potential confounding effects of stress sensitivity and chronotype (ones preferred time of day) since these are both factors known to be related to sleep quality. We found that, compared to those who reported good subjective sleep quality, participants who reported poor subjective sleep quality showed a negative cognitive bias towards emotionally negative stimuli. Also in agreement with previous work, we show that poor sleep quality has a negative effect on affective symptom measures- poor sleep quality relates to increased depressive symptoms, greater state and trait anxiety, and higher total mood disturbance (increased tension, fatigue, confusion and less vigor). Consistent with previous findings, we also found that subjective sleep quality was related to a decrease in performance on a sustained attention task. Although previous research suggests that stress sensitivity and chronotype would be important variables to consider in the impact of sleep perturbations on emotion processing, we did not find any stress, chronotype, or time of testing effects on these measures. (more…)
Author Interviews, Brigham & Women's - Harvard, CHEST, Sleep Disorders / 29.04.2015

dr-matthias-eikermann.jpgMedicalResearch.com Interview with: Matthias Eikermann, MD, PhD Associate Professor of Anaesthesia, Harvard Medical School Director of Research, Critical Care Division Massachusetts General Hospital Medical Research: What is the background for this study? What are the main findings? Dr. Eikermann: Obstructive sleep apnea occurs in about 5% of pregnant women, worsens as pregnancy progresses and is likely to persist into the early postpartum period. A main cause of anesthesia-related maternal death is postpartum airway obstruction. We observed among early postpartum women, that 45° upper body elevation increased upper airway diameter and mitigated sleep apnea, without adverse effects on quality of sleep after delivery. (more…)
Author Interviews, Cancer, Cancer Research / 15.04.2015

Josée Savard, Ph.D. School of Psychology, Laval University Cancer Research Center Quebec City, Quebec, CanadaMedicalResearch.com Interview with: Josée Savard, Ph.D. School of Psychology, Laval University Cancer Research Center Quebec City, Quebec, Canada MedicalResearch: What is the background for this study? What are the main findings? Dr. Savard: This paper reports on a secondary analysis of an 18-month longitudinal study initially conducted in 962 patients about to receive surgery for various types of cancer. The main results of this larger study indicated that insomnia is a significant problem in cancer patients. More precisely, it was found to affect up to 59% of patients at the peri-operative period. In addition, 32% of patients who were good sleepers developed insomnia symptoms at some point during the study (Savard et al., 2009; Savard et al., 2011). The goal of this particular analysis was to determine the role of cancer treatments and their side effects in triggering/aggravating insomnia symptoms during the 18-month follow-up. Study participants completed questionnaires assessing insomnia severity and somatic symptoms at baseline, as well as 2, 6, 10, 14 and 18 months later. This analysis was conducted separately in women treated for breast cancer (n=465) and men treated for prostate cancer (n=263). In breast cancer patients, chemotherapy and radiation therapy, but not hormone therapy, were found to be associated with increased insomnia severity. This deleterious effect appeared to be due to a number of side effects (e.g., nausea, night sweats, urinary symptoms). In prostate cancer patients, androgen-deprivation therapy was associated with aggravation of insomnia, an effect that was mainly due to the occurrence of night sweats. (more…)
Author Interviews, Circadian Rhythm, Ophthalmology, Sleep Disorders, UCSD / 09.04.2015

MedicalResearch.com Interview with: Carolina P B Gracitelli, M.D. Ophthalmology - PhD Candidate/ Research Fellow University of California San Diego - Hamilton Glaucoma Center  Medical Research: What is the background for this study? What are the main findings?  Dr. Gracitelli:  Of all the diseases that can lead to blindness, glaucoma is one of the most important diseases; it affects more than 70 million people worldwide, of whom approximately 10 % are bilaterally blind. Different studies have reported that the damage caused by glaucomatous disease lead to retinal ganglion cell (RGC) loss and consequently loss of intrinsically photosensitive retinal ganglion cells (ipRGCs), which is a subtype of RGC. This subpopulation of RGC is clearly related with non-image-forming visual function such as photic synchronization of circadian rhythms  and the pupillary light reflex. However, the true impact of glaucoma on sleep quality, sleep disturbance or circadian rhythm was until nowadays controversial. The main clinical finding of our study was that glaucoma leads to RGC death, including ipRGC death. These cells are connected to several non-image-forming functions, including circadian photoentrainment and pupillary reflexes. Therefore, the image-forming and non-image-forming visual systems are associated with glaucoma. Circadian function has not been well investigated in clinical daily practice, but it can interfere with the quality of life of these patients. Concerns about sleep disturbances in glaucoma patients should be incorporated into clinical evaluations.   Medical Research: What should clinicians and patients take away from your report? Dr. Gracitelli:  Our data support the concept that glaucoma is associated with a loss of ipRGCs that mediate the pupillary light response, particularly to the sustained component of the blue flash with a luminance of 250 cd/m2. Additionally, glaucoma patients had significant sleep disturbances that were inversely correlated with a measure of ipRGC function, the pupillary light reflex. These results suggest that the loss of ipRGCs in glaucoma may also lead to sleep disturbances. Both non-visual functions of ipRGCs are correlated, indicating that attention should be paid to the non-image forming visual functions in glaucoma patients.   Medical Research: What recommendations do you have for future research as a result of this study?  Dr. Gracitelli:  Sleep disorders is a complex system, therefore, some conclusions in this study should be carefully evaluated. Further studies with larger cohorts could also help to elucidate the association between the pupillary reflex and the polysomnography parameters. And longitudinal studies can better explain the associations between sleep disorders and glaucoma progression.  In addition, we know that there are several types of ipRGCs and they have specific functions (pupillary reflex or circadian rhythms), therefore, evaluations would also need to include a more thorough assessment to understand better the specific role of ipRGCs in sleep disturbances. However, it is true that these ipRGCs functions are impaired in glaucoma, affecting the quality of life of these patients.   Citation:   Intrinsically Photosensitive Retinal Ganglion Cell Activity Is Associated with Decreased Sleep Quality in Patients with Glaucoma  Gracitelli, Carolina P.B. et al. Ophthalmology Published Online: April 06, 2015 DOI: http://dx.doi.org/10.1016/j.ophtha.2015.02.030MedicalResearch.com Interview with: Carolina P B Gracitelli, M.D. Ophthalmology - PhD Candidate/ Research Fellow University of California San Diego - Hamilton Glaucoma Center Medical Research: What is the background for this study? What are the main findings? Dr. Gracitelli: Of all the diseases that can lead to blindness, glaucoma is one of the most important diseases; it affects more than 70 million people worldwide, of whom approximately 10 % are bilaterally blind. Different studies have reported that the damage caused by glaucomatous disease lead to retinal ganglion cell (RGC) loss and consequently loss of intrinsically photosensitive retinal ganglion cells (ipRGCs), which is a subtype of retinal ganglion cell. This subpopulation of RGC is clearly related with non-image-forming visual function such as photic synchronization of circadian rhythms and the pupillary light reflex. However, the true impact of glaucoma on sleep quality, sleep disturbance or circadian rhythm was until nowadays controversial. The main clinical finding of our study was that glaucoma leads to retinal ganglion cell death, including ipRGC death. These cells are connected to several non-image-forming functions, including circadian photoentrainment and pupillary reflexes. Therefore, the image-forming and non-image-forming visual systems are associated with glaucoma. Circadian function has not been well investigated in clinical daily practice, but it can interfere with the quality of life of these patients. Concerns about sleep disturbances in glaucoma patients should be incorporated into clinical evaluations. (more…)
Author Interviews, Endocrinology, JCEM, Metabolic Syndrome, Sleep Disorders / 03.04.2015

CDC- sleepMedicalResearch.com Interview with: Nan Hee Kim M.D., Ph.D., Professor Korea University Ansan Hospital, Gojan1-dong, Danwon-gu, Gyunggi-do, Korea MedicalResearch: What is the background for this study? Dr. Nan Hee Kim: Many individuals in modern society experience a discrepancy between social and biological time. Especially during the work or school week, we are often forced to be awake against our preferred time. In addition, the increase of light, TV, computer and internet make people stay up late at night. However, night owls (evening persons) have been reported to have more health and behavioral problems than morning persons. Evening persons experience eating disorders, negative mood and insufficient sleep compared to morning persons. They initiate sleep later in the night but need to wake up earlier than their biologic morning due to social demands. There is abundant evidence that short sleep duration and insomnia are significant risk factors for obesity and diabetes. Therefore, we feel the necessity to reveal whether evening persons are associated with metabolic abnormalities in the general population. MedicalResearch: What are the main findings? Dr. Nan Hee Kim: In middle-aged adults, people who stayed up late had a 1.7-fold increased risk for type 2 diabetes and metabolic syndrome, and a 3.2-fold increase in risk for sarcopenia as compared with morning persons, independent of sleep duration and lifestyle. Evening persons were associated with reduced muscle mass in men and increased fat mass including visceral fat in women. (more…)
Author Interviews, Sleep Disorders / 25.03.2015

MedicalResearch.com Interview with: Richard G. Stevens, Ph.D., Professor, Cancer Epidemiologist UConn Health Medical Research: What is the background for this study? What are the main findings? Dr. Stevens: Since first introducing the concept of a possible connection between exposure to light at night and breast cancer in the mid-80s, we’ve seen growing evidence of how artificial light can suppress the circadian hormone melatonin and bring about physiological changes. The extent of this “circadian disruption” varies by the type of light and the time of day. Humans evolved with a body clock that followed the solar clock. Nature intended us to be awake in daylight and at rest in the dark of night. Therefore, the intense, short-wavelength light of the sun in the morning triggers us to become awake and alert, just as the absence of sunlight in the evening allows our body to produce melatonin. Even with the use of fire to provide light in the evening, the circadian impact was relatively minimal because of firelight’s place on the red end of the visible spectrum. Humans survived under this simple formula for many thousands of years. Then electric light started to take an increasingly strong foothold in everyday life. Today we are typically surrounded at all hours of the day and night by artificial light – in many cases it’s not bright enough during the day to match the sun, and it’s too bright at night to be conducive to the natural sleep/wake cycle. Think computer screens, tablets, smart phones, e-readers, etc. These devices emit enough short-wavelength, or blue, light to disrupt our body clocks in the evening. So do fluorescent and LED lights. Our paper – I worked with Dr. Yong Zhu from Yale on this – represents a new analysis and synthesis of what we know up to now on the effect of lighting on our health. We don't know for certain, but there's growing evidence that the long-term implications of this may have ties to breast cancer, obesity, diabetes, and depression, and possibly other cancers. Exposure to electric light  started about 130 years ago,  which is a tiny period of time in evolutionary terms. In other words, not long enough to undo human evolution. (more…)
Author Interviews, Sexual Health, Sleep Disorders, University of Michigan / 24.03.2015

David A Kalmbach, PhD Sleep and Circadian Research Laboratory Department of Psychiatry University of Michigan Medical School MedicalResearch.com Interview with: David A Kalmbach, PhD Sleep and Circadian Research Laboratory Department of Psychiatry University of Michigan Medical School Medical Research: What is the background for this study? What are the main findings? Dr. Kalmbach: As it happens, my research background is in sexual health, and my clinical work is in behavioral sleep medicine. Therefore, I've long been interested in the intersection between sleep and sexual response, though there has been little research in this area. With the growing recognition of a wide range of morbidities associated with poor sleep, coupled with the multifactorial etiology of sexual dysfunctions, I wanted to investigate whether sleep disturbance was associated with poorer sexual response. Using a 2-week daily diary approach in a sample of 171 young women, we found that longer reported sleep duration led to greater sexual desire the next day. This relationship was mirrored by finding that the likelihood of partnered sexual activity was increased following nights during which women slept longer. We also found an association between genital arousal and sleep length, though this relationship was more complex. Women reported greater vaginal arousal during sexual activity following nights of shorter sleep. However, women who slept longer on average reported better vaginal arousal than women who obtained less sleep on average. This dual relationship may reflect differential effects of a single night of sleep deprivations versus chronic sleep deprivation. However, I think more research is needed to delineate the underlying mechanisms of these relationships. Even so, I think it is notable that daytime sequelae of poor sleep (e.g., mood changes, fatigue) did not account for the relationships between sleep and sexual response. (more…)
Author Interviews, Endocrinology, Pediatrics, Sleep Disorders, Vanderbilt / 28.02.2015

Dave Kennaway, PhD Professor, Lloyd Cox Senior Research Fellow, Head Circadian Physiology Laboratory School of Paediatrics and Reproductive Health Robinson Research Institute, Faculty of Health Sciences, Medical School, University of Adelaide AustraliaMedicalResearch.com Interview with: Dave Kennaway, PhD Professor Lloyd Cox Senior Research Fellow, Head Circadian Physiology Laboratory School of Paediatrics and Reproductive Health Robinson Research Institute, Faculty of Health Sciences, Medical School, University of Adelaide Australia MedicalResearch: What is the background for this review? What are the main findings? Dr. Kennaway: There is evidence that melatonin is being prescribed to for sleep disorders in children and adolescents who are developing normally despite the fact that there have been no properly designed studies on the effects of prolonged administration to children. In countries where melatonin has been registered, it is for use as a monotherapy for the short term treatment of primary insomnia, characterised by poor quality of sleep in patients who are aged 55 years and over. Use in Paediatrics is always “off-label”. After more than 50 years of melatonin research in animals there is overwhelming evidence that melatonin administration affects many organ systems. These include important effects on the reproductive organs of rodents, cats, ruminants and primates and melatonin is in fact registered as a veterinary drug for this purpose. The effects of melatonin, however, go beyond the potential reproductive consequences, including effects on cardiovascular, immune and metabolic systems. It is clear that many paediatricians, practitioners and parents are unaware of this. MedicalResearch: What should clinicians and patients take away from your report? Dr. Kennaway: Clinicians and patients need to recognise that melatonin is a hormone and not a drug developed for a specific purpose or illness. There have been no appropriate trials in children addressing the effects of prolonged administration of melatonin in children. Given the extensive literature on the role of the hormone in normal physiology it is unlikely that such trials would ever be approved. Should endocrine or other abnormalities appear in the future in children previously treated with melatonin it will not be tenable to argue that we were surprised. (more…)
Anesthesiology, Author Interviews, JAMA, Sleep Disorders / 24.02.2015

Nick Franks FSB, FRCA, FMedSci, FRS Professor of Biophysics and Anaesthetics, Professor William Wisden, Chair in Molecular NeuroscienceMedicalResearch.com Interview Professor Nick Franks  Professor of Biophysics and Anaesthetics Professor William Wisden, Chair in Molecular Neuroscience Department of Life sciences Wolfson Laboratories, Imperial College, South Kensington London Medical Research: What is the background for this study? What are the main findings? Profs. Franks and Wisden: We were interested in finding out how a particular type of sedative drug, dexmedetomidine, works in the brain. This drug is increasingly used during intensive care for sedation of patients, but unlike other powerful sedatives, it induces a state whereby the patient can be temporarily woken up. This is a highly useful property because it means patients can be both sedated and responsive during procedures. The drugged sedative state induced by dexmedetomidine struck us as being highly similar to the deep sleep that we all need to have if we have been extensively sleep deprived. If people and animals are kept awake for extended periods of time, they have to sleep. Most people know this from common experience - catching up on lost sleep. But how and why we need to sleep after sleep deprivation is not known. We found that dexmedetomidine-induced sedation and this recovery sleep used the same brain circuits, in a tiny area at the base of the brain called the preoptic hypothalamus. To do this we used a new genetic technique in mice that allowed us to mark or "tag" which neurons in the mouse’s brain were active during sedation or recovery sleep after sleep deprivation. The beauty of this technique is that we could then specifically reactivate these same neurons several days later with a special molecule that only binds to the tagged neurons. This reactivation caused the mice to go into a deep sleep. We concluded that the sedative drug dexmedetomidine copies or hijacks the mechanism used by the brain to respond to sleep deprivation and trigger deep sleep. (more…)
Author Interviews, CHEST, Lifestyle & Health, Obstructive Sleep Apnea / 24.02.2015

Matthew Buman PhD Asst Professor SNHP Exercise & Wellness Arizona State UniversityMedicalResearch.com Interview with: Matthew Buman PhD Asst Professor SNHP Exercise & Wellness Arizona State University   Medical Research: What is the background for this study? What are the main findings? Dr. Buman: A lack of physical activity is a known risk factor for insomnia, poor sleep, and obstructive sleep apnea. In addition to physical activity, sedentary behavior has emerged as an important behavior. Sedentary behavior is not just the lack of physical activity, but actually refers to the time someone spend sitting. This behavior has been shown to, independent of physical activity, be related to many poor health outcomes including cardiovascular disease, diabetes, and even premature death. This is the first study to examine whether there is a relationship between excess sitting and insomnia, poor sleep, and risk for obstructive sleep apnea. We found, after adjusting for physical activity and body weight (among other confounding factors), that total daily sitting was associated with poor sleep quality but not other sleep metrics or OSA risk. However, we also examined sitting while watching television and found a significant relationship between this type of sitting and a host of sleep quality metrics as well as risk for OSA. In a subsequent analysis we found that despite the independent relationship between sitting while watching television with OSA risk, those that were physically active were protected from this negative impact. (more…)
Author Interviews, Pediatrics, Pediatrics / 20.02.2015

Katherine M. Keyes, Ph.D. Assistant Professor of Epidemiology Columbia University Mailman School of Public Health New York, NY 10032MedicalResearch.com Interview with: Katherine M. Keyes, Ph.D. Assistant Professor of Epidemiology Columbia University Mailman School of Public Health New York, NY 10032 Medical Research: What is the background for this study? What are the main findings? Dr. Keyes: The Monitoring the Future study is an annually conducted survey of 8th, 10th, and 12th grade high school students in the United States, covering a wide range of adolescent health behaviors. The same questions on adolescent sleep were queried every year since 1991, allowing us to examine historical trends in the amount of sleep adolescents report. We found that there have been substantial decreases in the proportion of adolescents who report 7 or more hours of sleep on a regular basis, across all age groups and across all demographic groups. In the most recent years, after age 15, less than half of adolescents report regularly getting 7 or more hours of sleep every night. Given the importance of sleep in both the short and the long term for adolescent health, these findings suggest substantial public health concern. (more…)
Author Interviews, BMJ, Sleep Disorders / 18.02.2015

Karen Thorpe PhD Professor, Developmental Psychology Program Leader, Early Education and Development Group Program leader, Sleep in Early Childhood Group School of Psychology and Counselling Queensland University of Technology Australia MedicalResearch.com Interview with: Karen Thorpe PhD Professor, Developmental Psychology Program Leader, Early Education and Development Group Program leader, Sleep in Early Childhood Group School of Psychology and Counseling Queensland University of Technology Australia MedicalResearch: What is the background for this study? Professor Thorpe: Sleep is undoubtedly important not only for how well we think, feel and behave in our daily lives but also for longer-term health. In childhood, the quantity and quality of night-time and 24 hour sleep have consistently been identified as predictor of health. For example, night sleep predicts weight status. These findings have led to the hypothesis that increasing quantity of sleep through promoting daytime sleep would benefit child health. We sought to look for evidence on the independent effects of daytime sleep on child health, learning and behavior to assess whether this hypothesis was supported. (more…)
Author Interviews, JAMA, Sleep Disorders / 16.02.2015

David S. Black, Ph.D., M.P.H. Associate Professor of Preventive Medicine Keck School of Medicine of USC.MedicalResearch.com Interview with: David S. Black, Ph.D., M.P.H. Associate Professor of Preventive Medicine Keck School of Medicine of USC. Medical Research: What is the background for this study? What are the main findings? Dr. Black: Sleep disturbances pose a significant medical and public health concern for our nation’s aging population. An estimated 50% of people aged 55 years and older suffer from some form of sleep problem, including initiating and maintaining sleep. Sleep can be affected by a number of things. There are obvious factors like disturbances, dealing with insomnia or any form of aches and pains. But there is also one that many people have probably not considered. Traffic noise. Just like the factors listed previously, there is always a solution to a problem. There isn't anything that cannot be fixed. If you are someone that is having trouble sleeping due to the high level of traffic noises around your area, it may be best to look into a site like soundproofpanda.com to find a solution that can help reduce this issue and eventually provide you with a good's night sleep. Older adults report the highest prevalence of sleep problems compared to younger age groups when quantified by both self-report and biological assessment. Moderate sleep complaints in older adults are often associated with deficits in daytime functioning, including elevated levels of fatigue, disturbed mood such as depressive symptoms and reduced quality of life, and lead to the onset of clinical insomnia. Addressing moderate sleep complaints and sleep-related daytime dysfunction using community-accessible programs is a promising public health approach. Our main findings indicate that the mindfulness training program, which is available to the general community, resulted in improvement in sleep quality at post-intervention relative to a highly active and standardized sleep hygiene education program. Effect size for improvement in sleep quality was large (0.89) and of clinical relevance considering that effect sizes obtained from all types of behavioral interventions on self-reported sleep quality outcomes averages 0.76 in older adults. Meta-analyses comparing treatment modalities indicate that the mean effect size for self-reported sleep improvements resulting from pharmacotherapy (0.87) (i.e., benzodiazepines, benzodiazepine receptor agonists) and behavioral therapy (0.96) are of medium-to-large magnitude in mixed-age adult samples with primary insomnia. Thus, our observed changes are consistent with previous studies and are at the level of a minimally important difference for insomnia severity. The mindfulness program also yielded relative improvements on sleep-related daytime impairments of depression and fatigue symptoms that were of medium-to-large effect size. (more…)
Author Interviews, Brigham & Women's - Harvard, PNAS, Sleep Disorders / 06.02.2015

Christa Van Dort PhD Department of Anesthesia, Critical Care, and Pain Medicine, Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts General Hospital, Harvard Medical School Boston, MA, 02114MedicalResearch.com Interview with: Christa Van Dort PhD Department of Anesthesia, Critical Care, and Pain Medicine, Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts General Hospital, Harvard Medical School Boston, MA, 02114 Medical Research: What is the background for this study? What are the main findings? Dr. Van Dort:  Sleep is crucial for survival and maintenance of health.  Inadequate sleep and sleep disorders impair many brain and body functions such as executive function, the immune system and memory consolidation. The benefits of sleep are dependent on normal sleep physiology and patterns. Natural sleep is composed of non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep alternating every 90 min in humans.  Each stage provides different benefits, for example deep NREM sleep is associated with feeling rested and REM sleep is important for learning. Current sleep aids do not effectively restore normal sleep physiology or timing and as a result do not fulfill the important functions of natural sleep.  To develop new strategies for reproducing natural sleep, we aimed to understand each component of sleep (NREM and REM sleep) individually and then in combination. Cholinergic neurons have been hypothesized to control REM sleep for many years but no one had been able to test this directly due to limited methodology. Optogenetics solved this problem by giving us the ability to activate selectively the cholinergic neurons in the pedunculopontine tegmentum (PPT) and laterodorsal tegmentum (LDT). The primary finding of this study was that cholinergic neurons in the PPT and LDT are sufficient to drive REM sleep from NREM sleep. These cholinergic neurons were important for initiation of REM sleep but not the duration of REM sleep. Understanding REM sleep control is an important first step in reproducing normal sleep patterns and by itself could enhance learning and memory. (more…)