Sleep disorders common during COVID-19 pandemic

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Re: Sleep disorders common during COVID-19 pandemic

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Tim ,
that's a lot of reading ! ....and i thought that i read a lot :D Maybe I have sleep issues , or this just happens to be one of my favorite topics , but here I am ... wide awake at midnight again .



Individuals with high ADHD-traits are more vulnerable to insomnia

12/18/20


https://www.sciencedaily.com/releases/2 ... 084147.htm


Individuals with high ADHD-traits that do not meet the criteria for a diagnosis are less able to perform tasks involving attentional regulation or emotional control after a sleepless night than individuals with low ADHD-traits, a new study from Karolinska Institutet published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging reports.

While it can cause multiple cognitive impairments, there is considerable individual variation in sensitivity to the effects of insomnia. The reason for this variability has been an unresolved research question for long. In the present study, KI researchers investigated how sleep deprivation affects our executive functions, which is to say the central cognitive processes that govern our thoughts and actions. They also wanted to ascertain if people with ADHD tendencies are more sensitive to insomnia, with more severe functional impairments as a result.

ADHD (attention deficit hyperactivity disorder) is characterized by inattention, impulsiveness and hyperactivity; however, the symptoms vary from person to person and often also include emotional instability.

"You could say that many people have some subclinical ADHD-like symptoms but a diagnosis is only made once the symptoms become so prominent that they interfere with our everyday lives," says Predrag Petrovic, consultant and associate professor in psychiatry at the Department of Clinical Neuroscience at Karolinska Institutet, Sweden, who led the study along with Tina Sundelin and John Axelsson, both researchers at Karolinska Institutet and the Stress Research Institute at Stockholm University.

The study included 180 healthy participants between the ages of 17 and 45 without an ADHD diagnosis. Tendencies towards inattentiveness and emotional instability were assessed on the Brown Attention Deficit Disorder (B-ADD) scale.

The participants were randomly assigned to two groups, one that was allowed to sleep normally and one that was deprived of sleep for one night. They were then instructed to perform a test that measures executive functions and emotional control the following day (a Stroop test with neutral and emotional faces).

The researchers found that the sleep-deprived group showed worse performance in the experimental tasks (including more cognitive response variability). Moreover, people with high ADHD-traits were more vulnerable to sleep deprivation and showed greater impairment than those with low ADHD-traits.

The effects were also related to the most prominent type of subclinical ADHD-like symptom, in that after being deprived of sleep, the participants who displayed more everyday problems with emotional instability had larger problems with the cognitive task involving emotional regulation, and those who had more everyday inattention symptoms had larger problems with the non-emotional cognitive task.

"One of the reasons why these results are important is that we know that young people are getting much less sleep than they did just ten years ago," explains Dr Petrovic. "If young people with high ADHD-traits regularly get too little sleep they will perform worse cognitively and, what's more, their symptoms might even end up at a clinically significant level."

Story Source:

Materials provided by Karolinska Institutet.

Journal Reference:

Orestis Floros, John Axelsson, Rita Almeida, Lars Tigerström, Mats Lekander, Tina Sundelin, Predrag Petrovic. Vulnerability in Executive Functions to Sleep Deprivation Is Predicted by Subclinical Attention-Deficit/Hyperactivity Disorder Symptoms. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, 2020; DOI: 10.1016/j.bpsc.2020.09.019
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General anesthesia and normal sleep affect brain in an amazingly similar way as consciousness fades

12/29/21


https://www.sciencedaily.com/releases/2 ... 104525.htm


What happens in the brain when our conscious awareness fades during general anesthesia and normal sleep? Finnish scientists studied this question with novel experimental designs and functional brain imaging. They succeeded in separating the specific changes related to consciousness from the more widespread overall effects, and discovered that the effects of anesthesia and sleep on brain activity were surprisingly similar. These novel findings point to a common central core brain network fundamental for human consciousness.

Explaining the biological basis of human consciousness is one of the greatest challenges of science. While the loss and return of consciousness, as regulated by drugs or physiological sleep, have been employed as model systems in the study of human consciousness, previous research results have been confounded by many experimental simplifications.

"One major challenge has been to design a set-up, where brain data in different states differ only in respect to consciousness. Our study overcomes many previous confounders, and for the first time, reveals the neural mechanisms underlying connected consciousness," says Harry Scheinin, Docent of Pharmacology, Anesthesiologist, and the Principal Investigator of the study from the University of Turku, Finland.

A new and innovative experimental set-up

Brain activity was measured with positron emission tomography (PET) imaging during different states of consciousness in two separate experiments in the same group of healthy subjects. Measurements were made during wakefulness, escalating and constant levels of two anesthetic agents, and during sleep-deprived wakefulness and Non-Rapid Eye Movement (NREM) sleep.

In the first experiment, the subjects were randomly allocated to receive either propofol or dexmedetomidine (two anesthetic agents with different molecular mechanisms of action) at stepwise increments until the subjects no longer responded. In the sleep study, they were allowed to fall asleep naturally. In both experiments, the subjects were roused to achieve rapid recovery to a responsive state, followed by immediate and detailed interviews of subjective experiences from the preceding unresponsive period. Unresponsive anesthetic states and verified NREM sleep stages, where a subsequent report of mental content included no signs of awareness of the surrounding world, indicated a disconnected state in the study participants. Importantly, the drug dosing in the first experiment was not changed before or during the shift in the behavioral state of the subjects.

"This unique experimental design was the key idea of our study and enabled us to distinguish the changes that were specific to the state of consciousness from the overall effects of anesthesia," explains Annalotta Scheinin, Anesthesiologist, Doctoral Candidate and the first author of the paper.

Researchers discovered a common central core brain network


When PET images of responsive and connected brains were compared with those of unresponsive and disconnected, the scientists found that activity of the thalamus, cingulate cortices and angular gyri were affected independently of the used anesthetic agent, drug concentration and direction of change in the state of consciousness. Strikingly analogous findings were obtained when physiological sleep was compared with sleep-deprived wakefulness. Brain activity changes were much more extensive when the disconnected states were compared with a fully awake state. State-specific findings were thus distinct and separable from the overall effects of drug-induced anesthesia and natural sleep, which included widespread suppression of brain activity across cortical areas.

These findings identify a central core brain network that is fundamental for human consciousness.

"General anesthesia seems to resemble normal sleep more than has traditionally been thought. This interpretation is, however, well in line with our recent electrophysiological findings in another anesthesia study," says Harry Scheinin.

Subjective experiences are common during general anesthesia

Interestingly, unresponsiveness rarely denoted unconsciousness (i.e., total absence of subjective experiences), as most participants reported internally generated experiences, such as dreams, in the interviews. This is not an entirely new finding as dreams are commonly reported by patients after general anesthesia.

"However, because of the minimal delay between the awakenings and the interviews, the current results add significantly to our understanding of the nature of the anesthetic state. Against a common belief, full loss of consciousness is not needed for successful general anesthesia, as it is sufficient to just disconnect the patient's experiences from what is going on in the operating room," explains Annalotta Scheinin.

The new study sheds light on the fundamental nature of human consciousness and brings new information on brain functions in intermediate states between wakefulness and complete unconsciousness. These findings may also challenge our current understanding of the essence of general anesthesia.

The experiments were carried out at Turku PET Centre as a joint effort of the research groups of Harry Scheinin studying anesthesia mechanisms, and Professor of Psychology Antti Revonsuo studying human consciousness and the brain from the point of view of philosophy and psychology, in collaboration with Professor Michael Alkire from the University of California, Irvine, USA. Turku PET Centre is a Finnish National Research Institute established by University of Turku, Åbo Akademi University and Turku University Hospital. The study was funded by the Academy of Finland and the Jane and Aatos Erkko Foundation.

Story Source:

Materials provided by University of Turku.

Journal Reference:

Annalotta Scheinin, Oskari Kantonen, Michael Alkire, Jaakko Långsjö, Roosa E Kallionpää, Kaike Kaisti, Linda Radek, Jarkko Johansson, Nils Sandman, Mikko Nyman, Mika Scheinin, Tero Vahlberg, Antti Revonsuo, Katja Valli, Harry Scheinin. Foundations of human consciousness: Imaging the twilight zone. The Journal of Neuroscience, 2020; JN-RM-0775-20 DOI: 10.1523/JNEUROSCI.0775-20.2020
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Which came first, sleep or the brain?

1/8/21

https://www.sciencedaily.com/releases/2 ... 111055.htm


Stay awake too long, and thinking straight can become extremely difficult. Thankfully, a few winks of sleep is often enough to get our brains functioning up to speed again. But just when and why did animals start to require sleep? And is having a brain even a prerequisite?

In a study that could help to understand the evolutional origin of sleep in animals, an international team of researchers has shown that tiny, water-dwelling hydras not only show signs of a sleep-like state despite lacking central nervous systems but also respond to molecules associated with sleep in more evolved animals.

"We now have strong evidence that animals must have acquired the need to sleep before acquiring a brain," says Taichi Q. Itoh, assistant professor at Kyushu University's Faculty of Arts and Science and leader of the research reported in Science Advances.

While sleeping behavior was also recently found in jellyfish, a relative of hydras and fellow member of the phylum Cnidaria, the new study from researchers at Kyushu University in Japan and Ulsan National Institute of Science and Technology in Korea found that several chemicals eliciting drowsiness and sleep even in humans had similar effects on the species Hydra vulgaris.

"Based on our findings and previous reports regarding jellyfish, we can say that sleep evolution is independent of brain evolution," states Itoh.

"Many questions still remain regarding how sleep emerged in animals, but hydras provide an easy-to-handle creature for further investigating the detailed mechanisms producing sleep in brainless animals to help possibly one day answer these questions."

Only a couple of centimeters long, hydras have a diffuse network of nerves but lack the centralization associated with a brain.

While sleep is often monitored based on the measurement of brain waves, this is not an option for tiny, brainless animals.

As an alternative, the researchers used a video system to track movement to determine when hydras were in a sleep-like state characterized by reduced movement -- which could be disrupted with a flash of light.

Instead of repeating every 24 hours like a circadian rhythm, the researchers found that the hydras exhibit a four-hour cycle of active and sleep-like states.

More importantly, the researchers uncovered many similarities related to sleep regulation on a molecular and genetic level regardless of the possession of a brain.

Exposing the hydras to melatonin, a commonly used sleep aid, moderately increased the sleep amount and frequency, while the inhibitory neurotransmitter GABA, another chemical linked to sleep activity in many animals, greatly increased sleep activity.

On the other hand, dopamine, which causes arousal in many animals, actually promoted sleep in the hydras.

"While some sleep mechanisms appear to have been conserved, others may have switched function during evolution of the brain," suggests Itoh.

Furthermore, the researchers could use vibrations and temperature changes to disturb the hydras' sleep and induce signs of sleep deprivation, causing the hydras to sleep longer during the following day and even suppressing cell proliferation.

Investigating more closely, the researchers found that sleep deprivation led to changes in the expression of 212 genes, including one related to PRKG, a protein involved in sleep regulation in the wide range of animals, including mice, fruit flies, and nematodes.

Disrupting other fruit fly genes appearing to share a common evolutional origin with the sleep-related ones in hydras altered sleep duration in fruit flies, and further investigation of such genes may help to identify currently unknown sleep-related genes in animals with brains.

"Taken all together, these experiments provide strong evidence that animals acquired sleep-related mechanisms before the evolutional development of the central nervous system and that many of these mechanisms were conserved as brains evolved," says Itoh.


Story Source:

Materials provided by Kyushu University.

Journal Reference:

Hiroyuki J. Kanaya, Sungeon Park, Ji-hyung Kim, Junko Kusumi, Sofian Krenenou, Etsuko Sawatari, Aya Sato, Jongbin Lee, Hyunwoo Bang, Yoshitaka Kobayakawa, Chunghun Lim, Taichi Q. Itoh. A sleep-like state in Hydra unravels conserved sleep mechanisms during the evolutionary development of the central nervous system. Science Advances, 2020; 6 (41): eabb9415 DOI: 10.1126/sciadv.abb9415
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Mothers, but not fathers, with multiple children report more fragmented sleep

Study tracks sleep patterns of first-time and experienced parents

1/12/21


https://www.sciencedaily.com/releases/2 ... 163627.htm


Mothers with multiple children report more fragmented sleep than mothers of a single child, but the number of children in a family doesn't seem to affect the quality of sleep for fathers, according to a study from McGill University.

A total of 111 parents (54 couples and 3 mothers of single-parent families) participated in the study published in the Journal of Sleep Research led by McGill doctoral student Samantha Kenny under the supervision of Marie-Hélène Pennestri, Assistant Professor in the Department of Educational and Counselling Psychology.

Participants' sleep patterns were studied for two weeks. Mothers with one baby reported having less interrupted and better-quality sleep than mothers with more than one child, although the total amount of sleep did not differ depending on the number of children. No difference was noted in fathers.

"Experienced mothers perceived their sleep to be more fragmented than that of first-time mothers. Tension in the marital relationship may transpire if childcare is one-sided and not discussed collaboratively," says Pennestri, who is also a researcher at the Hôpital en santé mentale Rivière-des-Prairies (CIUSSS-NIM).

According to the researchers, interventions developed by healthcare providers targeting an equal distribution of daytime and nighttime childcare tasks could be helpful. These interventions should be tailored to each family member, depending on their situation.

As next steps, the researchers aim to explain the differences between mothers and fathers, and determine why mothers with more than one child report worse sleep.


Story Source:

Materials provided by McGill University.

Journal Reference:

Samantha Kenny, Rebecca Burdayron, Émilie Lannes, Karine Dubois‐Comtois, Marie‐Julie Béliveau, Marie‐Hélène Pennestri. Mothers’ and fathers’ sleep: Is there a difference between first‐time and experienced parents of 6‐month‐olds? Journal of Sleep Research, 2020; DOI: 10.1111/jsr.13238
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Fragmented sleep patterns can predict vulnerability to chronic stress

1/13/21


https://www.sciencedaily.com/releases/2 ... 085407.htm


New research from NYU Abu Dhabi's Laboratory of Neural Systems and Behavior for the first time used an animal model to demonstrate how abnormal sleep architecture can be a predictor of stress vulnerability. These important findings have the potential to inform the development of sleep tests that can help identify who may be susceptible -- or resilient -- to future stress.

In the study, Abnormal Sleep Signals Vulnerability to Chronic Social Defeat Stress, which appears in the journal Frontiers in Neuroscience, NYUAD Assistant Professor of Biology Dipesh Chaudhury and Research Associate Basma Radwan describe their development of a mouse model to detect how disruptions in Non-rapid Eye Movement (NREM) sleep result in increased vulnerability to future stress.

The researchers assessed the sleep characteristics of both stress-susceptible and stress-resilient mice before and after experiencing chronic social defeat (CSD) stress. The social behavior of the mice post-stress was classified in two main phenotypes: those susceptible to stress that displayed social avoidance and those that were resilient to stress. Pre-CSD, mice susceptible to stress displayed increased fragmentation of Non-Rapid Eye Movement (NREM) sleep due to increased switching between NREM and wake and shorter average duration of NREM bouts, relative to mice resilient to stress. Their analysis showed that the pre-CSD sleep features from both phenotypes of mice allowed prediction of susceptibility to stress with more than 80 percent accuracy. Post-CSD, susceptible mice maintained high NREM fragmentation during the light and dark phase while resilient mice exhibited high NREM fragmentation only in the dark.

The findings demonstrate that mice that become susceptible to CSD stress exhibit pre-existing abnormal sleep/wake characteristics prior to stress exposure. In addition, subsequent exposure to stress further impairs sleep and the homeostatic response.

"Our study is the first to provide an animal model to investigate the relationship between poor sleep continuity and vulnerability to chronic stress and depressive disorders," said Chaudhury and Radwan. "This marker of vulnerability to stress opens up avenues for many possible future studies that could further explain the underlying molecular processes and neural circuitry that lead to mood disorders."


Story Source:

Materials provided by New York University.

Journal Reference:

Basma Radwan, Gloria Jansen, Dipesh Chaudhury. Abnormal Sleep Signals Vulnerability to Chronic Social Defeat Stress. Frontiers in Neuroscience, 2021; 14 DOI: 10.3389/fnins.2020.610655
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How the brain paralyzes you while you sleep

1/14/21


https://www.sciencedaily.com/releases/2 ... 085417.htm


We laugh when we see Homer Simpson falling asleep while driving, while in church, and while even operating the nuclear reactor. In reality though, narcolepsy, cataplexy, and rapid eye movement (REM) sleep behavior disorder are all serious sleep-related illnesses. Researchers at the University of Tsukuba led by Professor Takeshi Sakurai have found neurons in the brain that link all three disorders and could provide a target for treatments.

REM sleep correlates when we dream. Our eyes move back and forth, but our bodies remain still. This near-paralysis of muscles while dreaming is called REM-atonia, and is lacking in people with REM sleep behavior disorder. Instead of being still during REM sleep, muscles move around, often going as far as to stand up and jump, yell, or punch. Sakurai and his team set out to find the neurons in the brain that normally prevent this type of behavior during REM sleep.

Working with mice, the team identified a specific group of neurons as likely candidates. These cells were located in an area of the brain called the ventral medial medulla and received input from another area called the sublaterodorsal tegmental nucleus, or SLD. "The anatomy of the neurons we found matched what we know," explains Sakurai. "They were connected to neurons that control voluntary movements, but not those that control muscles in the eyes or internal organs. Importantly, they were inhibitory, meaning that they can prevent muscle movement when active." When the researchers blocked the input to these neurons, the mice began moving during their sleep, just like someone with REM sleep behavior disorder.

Narcolepsy is characterized by suddenly falling asleep at any time during the day, even in mid-sentence. Cataplexy is a related illness in which people suddenly lose muscle tone and collapse. Although they are awake, their muscles act as if they are in REM sleep. Sakurai and his team suspected that the special neurons they found were related to these two disorders. They tested their hypothesis using a mouse model of narcolepsy in which cataplexic attacks could be triggered by chocolate. "We found that silencing the SLD-to-ventral medial medulla reduced the number of cataplexic bouts," says Sakurai.

Overall, the experiments showed these special circuits control muscle atonia in both REM sleep and cataplexy. "The glycinergic neurons we have identified in the ventral medial medulla could be a good target for drug therapies for people with narcolepsy, cataplexy, or REM sleep behavior disorder," says Sakurai. "Future studies will have to examine how emotions, which are known to trigger cataplexy, can affect these neurons."


Story Source:

Materials provided by University of Tsukuba.

Journal Reference:

Shuntaro Uchida, Shingo Soya, Yuki C. Saito, Arisa Hirano, Keisuke Koga, Makoto Tsuda, Manabu Abe, Kenji Sakimura, Takeshi Sakurai. A discrete glycinergic neuronal population in the ventromedial medulla that induces muscle atonia during REM sleep and cataplexy in mice. The Journal of Neuroscience, 2020; JN-RM-0688-20 DOI: 10.1523/JNEUROSCI.0688-20.2020
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Deep sleep takes out the trash

Waste clearance is crucial for brain health, preventing neurodegenerative disease

1/20/21



A new Northwestern University study reaffirms the importance of getting a good night's sleep.

By examining fruit flies' brain activity and behavior, the researchers found that deep sleep has an ancient, restorative power to clear waste from the brain. This waste potentially includes toxic proteins that may lead to neurodegenerative disease.

"Waste clearance could be important, in general, for maintaining brain health or for preventing neurogenerative disease," said Dr. Ravi Allada, senior author of the study. "Waste clearance may occur during wake and sleep but is substantially enhanced during deep sleep."

The study will publish tomorrow (Jan. 20) in the journal Science Advances.

Allada is the Edward C. Stuntz Distinguished Professor in Neuroscience and chair of the Department of Neurobiology in the Northwestern's Weinberg College of Arts and Sciences. He also is associate director of Northwestern's Center for Sleep and Circadian Biology. Bart van Alphen, a postdoctoral fellow in Allada's laboratory, was the paper's first author.

Although fruit flies seem very different from humans, the neurons that govern flies' sleep-wake cycles are strikingly similar to our own. For this reason, fruit flies have become a well-studied model organism for sleep, circadian rhythms and neurodegenerative diseases.

In the current study, Allada and his team examined proboscis extension sleep (PES), a deep-sleep stage in fruit flies, which is similar to deep, slow-wave sleep in humans. The researchers discovered that, during this stage, fruit flies repeatedly extend and retract their proboscis (or snout).

"This pumping motion moves fluids possibly to the fly version of the kidneys," Allada said. "Our study shows that this facilitates waste clearance and aids in injury recovery."

When Allada's team impaired flies' deep sleep, the flies were less able to clear an injected non-metabolizable dye from their systems and were more susceptible to traumatic injuries.

Allada said this study brings us closer to understanding the mystery of why all organisms need sleep. All animals -- especially those in the wild -- are incredibly vulnerable when they sleep. But research increasingly shows that the benefits of sleep -- including crucial waste removal -- outweigh this increased vulnerability.

"Our finding that deep sleep serves a role in waste clearance in the fruit fly indicates that waste clearance is an evolutionary conserved core function of sleep," the paper's coauthors write. "This suggests that waste clearance may have been a function of sleep in the common ancestor of flies and humans."

The study, "A deep sleep stage in Drosophila with a functional role in waste clearance," was supported by the U.S. Army (award numbers W81XWH-16-1-0169, W81XWH-16-1-0166, and W81XWH2010211) and the Alzheimer's Association (award number AARG-17-532626).

Story Source:

Materials provided by Northwestern University.

Journal Reference:

Bart van Alphen, Evan R. Semenza, Melvyn Yap, Bruno van Swinderen, Ravi Allada. A deep sleep stage in Drosophila with a functional role in waste clearance. Science Advances, 2021; 7 (4): eabc2999 DOI: 10.1126/sciadv.abc2999
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MRI helps unravel the mysteries of sleep

1/22/21


https://www.sciencedaily.com/releases/2 ... 085009.htm


Scientists are investigating brain activity during sleep with the help of MRI scans. It turns out our brains are much more active than we thought. Our state of consciousness changes significantly during stages of deep sleep, just as it does in a coma or under general anesthesia. Scientists have long believed -- but couldn't be certain -- that brain activity declines when we sleep. Most research on sleep is conducted using electroencephalography (EEG), a method that entails measuring brain activity through electrodes placed along a patient's scalp. However, Anjali Tarun, a doctoral assistant at EPFL's Medical Image Processing Laboratory within the School of Engineering, decided to investigate brain activity during sleep using magnetic resonance imaging, or MRI. According to Dimitri Van De Ville, who heads the lab, "MRI scans measure neural activity by detecting the hemodynamic response of structures throughout the brain, thereby providing important information in addition to EEGs." During these experiments, Tarun relied upon EEG to identify when the study participants had fallen asleep and pinpoint the different stages of sleep. Then she examined the MRI images to generate spatial maps of neural activity and determine different brain states.

Difficult data to obtain

The only catch was that it wasn't easy to perform brain MRIs on participants while they were sleeping. The machines are very noisy, making it hard for participants to reach a state of deep sleep. But working with Prof. Sophie Schwartz at the University of Geneva and Prof. Nikolai Axmacher at Ruhr-Universität Bochum, Tarun could leverage simultaneous MRI and EEG data from around thirty people. The brain-activity data were covered a period of nearly two hours while participants were sleeping in an MRI machine. "Two hours is a relatively long time, meaning we were able to obtain a set of rare, reliable data," says Tarun. "MRIs carried out while a patient is performing a cognitive task usually last around 10-30 minutes."

Brain activity during sleep

After checking, analyzing and comparing all the data, what Tarun found was surprising. "We calculated exactly how many times networks made up of different parts of the brain became active during each stage of sleep," she says. "We discovered that during light stages of sleep -- that is, between when you fall asleep and when you enter a state of deep sleep -- overall brain activity decreases. But communication among different parts of the brain becomes much more dynamic. We think that's due to the instability of brain states during this phase." Van De Ville adds: "What really surprised us in all this was the resulting paradox. During the transition phase from light to deep sleep, local brain activity increased and mutual interaction decreased. This indicates the inability of brain networks to synchronize."

The role of default-mode networks and the cerebellum

Consciousness is generally associated with neural networks that may be linked to our introspection processes, episodic memory and spontaneous thought. "We saw that the network between the anterior and posterior regions broke down, and this became increasingly pronounced with increasing sleep depth," says Van De Ville. "A similar breakdown in neural networks was also observed in the cerebellum, which is typically associated with motor control." For now, the scientists don't know exactly why this happens. But their findings are a first step towards a better understanding of our state of consciousness while we sleep. "Our findings show that consciousness is the result of interactions between different brain regions, and not in localized brain activity," says Tarun. "By studying how our state of consciousness is altered during different stages of sleep, and what that means in terms of brain network activity, we can better understand and account for the wide range of brain functions that characterize us as human beings."

Story Source:

Materials provided by Ecole Polytechnique Fédérale de Lausanne.

Journal Reference:


Anjali Tarun, Danyal Wainstein-Andriano, Virginie Sterpenich, Laurence Bayer, Lampros Perogamvros, Mark Solms, Nikolai Axmacher, Sophie Schwartz, Dimitri Van De Ville. NREM sleep stages specifically alter dynamical integration of large-scale brain networks. iScience, 2021; 24 (1): 101923 DOI: 10.1016/j.isci.2020.101923
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Lack of sleep, stress can lead to symptoms resembling concussion

1/22/21


https://www.sciencedaily.com/releases/2 ... 112323.htm


A new study suggests that a lot of people might be going through life with symptoms that resemble concussion -- a finding supporting researchers' argument that athletes recovering from a brain injury should be assessed and treated on a highly individualized basis.

In the national study, between 11% and 27% of healthy college athletes with no history of a recent concussion reported combinations of symptoms that met criteria for post-concussion syndrome (PCS) as defined by an international classification system. Among the nearly 31,000 student-athletes surveyed, three factors stood out as the most likely to predict PCS-like symptoms: lack of sleep, pre-existing mental health problems and stress.

The participants were cadets from four U.S. military service academies -- who undergo rigorous training and are required to participate in athletics -- and students who competed in NCAA sports at 26 U.S. higher education institutions.

Beyond the substantial numbers of students who reported clusters of PCS-like symptoms, between one-half and three-quarters of all of the athletes surveyed reported one or more symptoms commonly experienced by people who've had a concussion, the most common being fatigue or low energy and drowsiness.

"The numbers were high, and were consistent with previous research in this area, but it is quite shocking," said study lead author Jaclyn Caccese, assistant professor in The Ohio State University School of Health and Rehabilitation Sciences. "These are elite athletes who are physically fit, and they are experiencing that many symptoms commonly reported following concussion. So looking across the general population, they'd probably have even more."

It's important to understand that there are multiple sources of these symptoms, researchers say, so that student-athletes' post-concussion care zeroes in on symptoms caused by the injury. In addition, knowing athletes' medical history and baseline symptom status may help clinicians predict which pre-existing factors could contribute to a slower recovery from a concussion.

"When a patient comes into a clinic and they are a month or more out from their most recent concussion, we need to know what symptoms they were experiencing before their concussion to know if their symptoms are attributable to their concussion or something else. Then we can start treating the concussion-related symptoms to hopefully help people recover more quickly," Caccese said.

This study, published last week in the journal Sports Medicine, was conducted by the Concussion Assessment, Research and Education (CARE) Consortium established by the NCAA and U.S. Department of Defense. Caccese completed the research while she was a PhD student and postdoctoral researcher at the University of Delaware, a consortium member institution.

The initiative is designed to fill gaps in knowledge about concussion effects and recovery among student-athletes at colleges, universities and military service academies by collecting and analyzing data on men and women who compete in a range of sports and undergo military training.

Participants in this study included 12,039 military service academy cadets and 18,548 NCAA student-athletes who completed the Sport Concussion Assessment Tool symptom evaluation as part of the consortium's baseline testing. The consortium also collected demographic data and personal and family medical histories from participants.

Statistical analyses showed which factors in athletes' medical histories were most closely associated with reports of symptoms that aligned with PCS criteria. Among cadets, 17.8% of men and 27.6% of women reported a cluster of symptoms that met PCS criteria. Among NCAA athletes, 11.4% of men and 20% of women reported combined symptoms that mimicked the PCS criteria. (Caccese said the varied timing of data collection at military service academies compared to NCAA preseason testing likely contributed to the symptoms reported by a higher percentage of cadets.)

For both groups, sleep problems -- and particularly insufficient sleep the night before the test -- and pre-existing psychiatric disorders were the most predictive conditions, and a history of migraines also contributed to symptoms that met PCS criteria. In cadets, academic problems and being a first-year student increased odds of having symptoms that met PCS criteria, and in NCAA athletes, a history of ADHD or depression contributed to meeting PCS criteria.

The International Classification of Diseases, Tenth Revision uses the term post-concussion syndrome for persistent symptoms following concussion, although the cause or causes of these symptoms can be difficult to determine. Symptoms range from persistent headaches, dizziness and fatigue to anxiety, insomnia and loss of concentration and memory.

A complicating factor with high symptom reporting is that recognizing concussion and determining return to play is based on reported symptoms. And while some symptoms may be more closely connected to concussion than others -- such as dizziness, pressure in the head, or sensitivity to light or noise -- others, like fatigue, drowsiness and even headaches, can be linked to a variety of causes.

"Perhaps we can create a battery of symptoms more specific to concussion," Caccese said. "That is another project in this series -- trying to see if there are groups of symptoms or specific symptoms that may be more able to identify individuals with concussion."

The CARE Consortium also aims to identify factors that will help predict outcomes in student-athletes and cadets who suffer concussions.

"This hopefully not only shows clinicians that we need to consider how people would have presented before injury, but also provides some normative data so they can interpret other patients' data," Caccese said. "We really don't know a lot about why people have persistent symptoms, and it seems to be very variable. So we're trying to understand this better to help predict who will have a prolonged recovery, and who will not."


Story Source:

Materials provided by Ohio State University.

Journal Reference:

Jaclyn B. Caccese, Grant L. Iverson, Katherine J. Hunzinger, Breton M. Asken, James R. Clugston, Kenneth L. Cameron, Megan N. Houston, Steven J. Svoboda, Jonathan C. Jackson, Gerald T. McGinty, Carlos A. Estevez, Adam J. Susmarski, Alexander Enrique, Kelsey N. Bryk, Steven P. Broglio, Thomas W. McAllister, Michael McCrea, Paul F. Pasquina, Thomas A. Buckley. Factors Associated with Symptom Reporting in U.S. Service Academy Cadets and NCAA Student Athletes without Concussion: Findings from the CARE Consortium. Sports Medicine, 2021; DOI: 10.1007/s40279-020-01415-4
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Re: Sleep disorders common during COVID-19 pandemic

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Afternoon napping linked to better mental agility

Associated with better locational awareness, verbal fluency, and working memory

1/25/21


https://www.sciencedaily.com/releases/2 ... 191846.htm


Taking a regular afternoon nap may be linked to better mental agility, suggests research published in the online journal General Psychiatry.

It seems to be associated with better locational awareness, verbal fluency, and working memory, the findings indicate.

Longer life expectancy and the associated neurodegenerative changes that accompany it, raise the prospect of dementia, with around 1 in 10 people over the age of 65 affected in the developed world.

As people age, their sleep patterns change, with afternoon naps becoming more frequent. But research published to date hasn't reached any consensus on whether afternoon naps might help to stave off cognitive decline and dementia in older people or whether they might be a symptom of dementia.

The researchers explored this further in 2214 ostensibly healthy people aged at least 60 and resident in several large cities around China, including Beijing, Shanghai, and Xian.

In all, 1534 took a regular afternoon nap, while 680 didn't. All participants underwent a series of health checks and cognitive assessments, including the Mini Mental State Exam (MMSE) to check for dementia.

The average length of night time sleep was around 6.5 hours in both groups.

Afternoon naps were defined as periods of at least five consecutive minutes of sleep, but no more than 2 hours, and taken after lunch. Participants were asked how often they napped during the week; this ranged from once a week to every day.

The dementia screening tests included 30 items that measured several aspects of cognitive ability, and higher function, including visuo-spatial skills, working memory, attention span, problem solving, locational awareness and verbal fluency.

The MMSE cognitive performance scores were significantly higher among the nappers than they were among those who didn't nap. And there were significant differences in locational awareness, verbal fluency, and memory.

This is an observational study, and so can't establish cause. And there was no information on the duration or timing of the naps taken, which may be important.

But there are some possible explanations for the observations found, say the researchers.

One theory is that inflammation is a mediator between mid-day naps and poor health outcomes; inflammatory chemicals have an important role in sleep disorders, note the researchers.

Sleep regulates the body's immune response and napping is thought to be an evolved response to inflammation; people with higher levels of inflammation also nap more often, explain the researchers.


Story Source:

Materials provided by BMJ.

Journal Reference:

Han Cai, Ning Su, Wei Li, Xia Li, Shifu Xiao, Lin Sun. Relationship between afternoon napping and cognitive function in the ageing Chinese population. General Psychiatry, 2021; 34 (1): e100361 DOI: 10.1136/gpsych-2020-100361
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