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States that the hippocampus is a major part of the brain that controls the cognitive processes and something we use every second.  A loss of sleep can  negatively impact this particular region of the brain because neurons that act as communication between the hippocampus and the rest of the body disappear when an individual is sleep deprived.  Continues by adding that while deprived of sleep, neural connections in the brain are being destroyed which is causing the size of the hippocampus to decrease. I question why the hippocampus shrinks while the neurons are being destroyed.  "After the analyzing the results, we saw a dramatic thirty percent spine loss after sleep deprivation in the hippocampus."

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Sleep deprivation and memory problems | Robbert Havekes | TEDxDenHelder

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Source states the very harmful physical and mental effects that sleep deprivation can have on individuals. Adenosine and Melatonin are two key chemicals that send us into sleep and allow our body and brain to relax. Continues by saying that a large group of Americans from every age group are regularly sleep deprived.  Also explains that sleep deprivation causes toxic waste to build up in the brain which can lead to many terrible effects.  The glymphatic system gets rid of this waste and is active during sleep.  Since Melatonin and Adenosine send us to sleep, I wonder if caffeine kills these chemicals to wake us up. "Losing shut eye can result in hormonal imbalance, problems with memory and illness."

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What would happen if you didn’t sleep? - Claudia Aguirre

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Article discusses the importance of sleep and the effects a clock controlled world has on peoples sleep habits.  States that sleep deprivation can lead to twitching and muscular discomfort.  Continues by saying that an average person would need eight to ten hours of sleep a night and that most Americans believe they can manage on much less. Adds interesting information by saying that an individual can not make up for the lost sleep by just resting.  And when doing tasks that don't require much effort such as reading and you feel sleepy, this means you are sleep deprived. I realize that this can actually be a good technique to use to test whether I am getting enough sleep for my body. "Although most people tend to minimize the effects of insufficient sleep as simply feeling a bit tired, studies of sleep-deprived people have shown that they are less efficient and more irritable."

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PERSONAL HEALTH; Facing Up to the Realities of Sleep Deprivation

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PERSONAL HEALTH WAKE UP! This is National Sleep Awareness Week and judging from a national survey, Americans remain woefully ignorant about sleep, its critical role in their lives and the hazards of not getting enough of it. How serious is this ignorance?

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Essay investigates the hypothesis that sleep deprivation during the ages of  18 - 25  can cause many effects which can be very costly for the brain in the long term and short term.  Through research, finds that sleep deprivation can cause memory loss in the long term, but worsen the ability to memorize in the short term.  The ability to focus and learn decreases and it also stated that when deprived of sleep, toxic waste that is common in Alzheimer’s patients, clumps together in the brain.  Raises an interesting question by asking whether different sleep patterns of the different cultures around the world had an effect on the percentage of sleep deprived individuals and the development of brain dysfunctions. "Sleep deprivation makes it difficult for brain cells to communicate effectively, which can lead to temporary mental lapses that affect memory and visual perception."

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The academic journal article says that memory is divided into three different parts. There is acquisition, where the brain acquires new information.  Consolidation, when the brain makes this information a stable memory.  Then there's recall, when it's able to refer back to this memory. The first and third ones happen while an individual is awake, while the third happens when they are asleep.  The article also says that slow-wave-sleep, which is deep sleep, can play a huge role in the processing and consolidating of memories and learning.  Now I understand why people tend to do better on tests if they get a good night sleep rather than staying up all night studying.  "Consolidation takes place during sleep through the strengthening of the neural connections that form our memories."

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Sleep, Learning, and Memory | Healthy Sleep

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Sleep, learning, and memory are complex phenomena that are not entirely understood. However, animal and human studies suggest that the quantity and quality of sleep have a profound impact on learning and memory. Research suggests that sleep helps learning and memory in two distinct ways. First, a sl…

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According to the article, sleep deprivation can cause an individual to literally lose the ability and/or willingness to go through with a certain task, a task that they would be able to do on a regular night of rest.  The article also states that as a result of this, the memory of the individual is being strained which causes the ability to remember or memorize decreased significantly.  This was true for me when I pulled an all nighter and the next day it was very hard to memorize a couple of formulas in calculus. It continued by stating that sleep deprivation even caused interruptions with in the brain and it's functions while the individual was trying to perform daily, routine tasks.  "If management of proactive interference is the cause, then the density of interruptions or other memory events in time may be more important than the length of time itself."

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By: Michelle E. Stepan
Department of Psychology, Michigan State University;
Kimberly M. Fenn
Department of Psychology, Michigan State University
Erik M. Altmann
Department of Psychology, Michigan State University

Acknowledgement: This research was supported by Grant N000141612841 from the Office of Naval Research to Kimberly M. Fenn and Erik M. Altmann.

Sleep deprivation is known to affect attention and vigilance (e.g., Lim & Dinges, 2008; Norton, 1970; Wimmer, Hoffmann, Bonato, & Moffitt, 1992), but questions remain about its effects on higher-order cognitive processes (see Killgore, 2010 for review). Some studies found that sleep deprivation impaired working memory ( Chee & Choo, 2004; Chee et al., 2006; Choo, Lee, Venkatraman, Sheu, & Chee, 2005; Durmer, & Dinges, 2005; Habeck et al., 2004; Mu et al., 2005) or executive function ( Durmer & Dinges, 2005; Nilsson et al., 2005), whereas others found no effect on higher-order processes ( Binks, Waters, & Hurry, 1999; Nilsson et al., 2005; Tucker, Whitney, Belenky, Hinson, & Van Dongen, 2010; Wimmer et al., 1992). Some studies even found divergent effects using the same task ( Chee & Choo, 2004; Chee et al., 2006). These equivocal findings may be a function of relatively small sample sizes.

Here we studied effects of sleep deprivation on error rates in a procedural task, focusing on the role of memory maintenance. In our task, participants perform a set of steps in a prescribed sequence. Every few trials-a trial being a performed step-the participant is interrupted for about 20 s. After the interruption, the participant must resume the interrupted sequence with the correct step. To know which step is correct, the participant must remember the last step performed before the interruption. Maintaining a memory for that step is made difficult by interference from the interrupting task.

The theoretical question we address is whether sleep deprivation affects memory processes and, if so, whether the effects are mediated by global cognitive impairments or impairments of memory-related processes specifically. We isolate effects on memory processes by comparing two trial types that differ only in the need for memory maintenance. A postinterruption trial follows an interruption, whereas a baseline trial follows another trial. The processing for the two trial types is identical except that a postinterruption trial requires recall of the step performed before the interruption, and therefore depends on memory maintenance during the interruption. Both trial types should show effects of global factors, such as increased fatigue or wake state instability ( Doran, Van Dongen, & Dinges, 2001; Lim & Dinges, 2008). Only postinterruption trials should show effects specific to memory maintenance. Deprivation studies involving higher level tasks (e.g., Caldwell & Ramspott, 1998; Hack, Choi, Vijayapalan, Davies, & Stradling, 2001; Thomas et al., 2000) typically do not include measures such as our baseline trials that allow effects on higher-order processes to be isolated like this. We can also measure time-on-task effects specifically on memory maintenance because there are many postinterruption and baseline trials per session. Time-on-task effects after reduced sleep are well documented in vigilance tasks (e.g., Doran et al., 2001; Van Dongen, Maislin, Mullington, & Dinges, 2003) but have not been widely studied for higher-order cognitive processes. Finally, we aimed for conclusive results by testing a large sample. To our knowledge, ours is the largest study of the effect of sleep deprivation on higher-order cognition.

Participants

Informed consent was obtained from all participants and the study was approved by Michigan State University's Institutional Review Board. Participants were Michigan State University undergraduates who were native English speakers, had never been diagnosed with a memory or sleep disorder, were not color blind, and had no strong morning or evening preference (scores of 42 to 58 on the Morningness-Eveningness Questionnaire; Horne & Ostberg, 1976) or major sleep disturbances (scores of 0 to 10 on the sleep disturbance section of the Pittsburgh Sleep Quality Index; Buysse, Reynolds, Monk, Berman, & Kupfer, 1989). On the night before the study, they slept at least 6 hrs and woke by 9:00 a.m. They also refrained from napping prior to their arrival in the laboratory. They were permitted no caffeine, alcohol, or drugs for 24 hr prior to the study.

Of an initial sample of 269 participants, 20 were lost to attrition, two to caffeine consumption, one to technical problems, and 12 to failure to maintain criterion accuracy (discussed in the Materials section) in Session 1. Data from the remaining 234 participants (18 to 25 years old, Mage = 19.02, SD = 1.19; 138 women) were submitted to analysis. Participants were run in groups of up to 11, across two testing rooms, and were given course credit as compensation.

Materials

Here we summarize key elements of the procedural task; detailed descriptions are presented in Altmann, Trafton, and Hambrick (2014, 2017). Participants performed a sequence of seven steps in a loop. The correct order of the steps is specified by an acronym, UNRAVEL. Each letter of UNRAVEL identifies a different two-alternative forced-choice decision rule to apply to a randomly generated stimulus. Figure 1 shows two sample stimuli, the seven decision rules, and the correct response to each stimulus according to each rule to illustrate the various decisions. The stimulus contains no information about the step to perform next, so participants must remember where they are in the sequence. When participants reach the "L" step they start over with the "U" step.

Figure 1. Above: Example of two randomly generated stimuli from the UNRAVEL task (where each letter of UNRAVEL identifies a different two-alternative forced-choice decision rule to apply to a randomly generated stimulus). Below: The UNRAVEL rules that correspond to each step (letter) in the UNRAVEL acronym, and the correct keyboard responses for each rule based on the two stimuli above. The letters in boldface type represent the possible response options for each rule. Adapted from "Momentary interruptions can derail the train of thought," by E. M. Altmann, J. G. Trafton, and D. Z. Hambrick, 2014, Journal of Experimental Psychology: General, 143, pp. 215-226. Copyright 2014 by the American Psychological Association.

There were four blocks of trials per session. Each block contained 66 trials on average ( SD = 12) and was interrupted 10 times at random points by a typing task in which participants had to correctly transcribe two letter strings, each consisting of the 14 UNRAVEL responses (see Figure 1) presented in random order. After the second string, participants had to pick up where they left off in the UNRAVEL sequence. An interruption lasted about 20 s ( M = 22.47, SD = 6.47). A session took about 35 min ( M = 36.13, SD = 9.25).

We measured accuracy in terms of sequence errors and nonsequence errors. A sequence error occurred if the participant performed the wrong successor of the step performed immediately prior. For example, if steps "N," "R," "V," and "E" were performed in succession, "V" would be a sequence error because that step should have been "A." However, "E" would be correct because it follows "V." A nonsequence error occurred if the participant performed the correct step but made the incorrect response for that step given the stimulus (because all 14 responses are unique, we could infer the intended step from any response). A trial was coded as correct if there was neither a sequence nor a nonsequence error.

If fewer than 70% of trials in a block were correct, the participant was instructed to be more accurate at the end of the block. We coded a session as a failure if accuracy was below 70% on two or more blocks, on grounds that the participant did not follow the instruction to be more accurate. We excluded participants who failed Session 1 from all analyses because we could not be sure they understood the task.

Procedure

Participants were recruited for a study on sleep deprivation and told they would either remain awake all night or be permitted to sleep. They arrived at 10:00 p.m. for Session 1 and completed sleepiness and mood assessments, as discussed in the online supplemental material. Next, participants completed the UNRAVEL task and a battery of cognitive and personality measures that were part of a separate study. After completing all tasks (∼2 hrs), participants were randomly assigned to conditions. Researchers and participants were blind to condition until all evening testing was finished. Participants randomly assigned to the sleep group ( n = 112) were given a Charge 2 activity monitor (Fitbit Inc., San Francisco, CA) to track their sleep, and then given a ride home. Participants assigned to the deprivation group ( n = 122) stayed awake overnight in the laboratory.

Deprivation participants were monitored throughout the night by two trained research assistants (see the online supplemental material for further information). They were permitted to read, do homework, watch TV/movies, play games, or engage in other quiet activities but were not permitted to engage in activities that activated the autonomic nervous system. We provided water and snacks and allowed participants to consume anything that did not contain caffeine or alcohol. Every 2 hrs, participants completed sleepiness and mood assessments. Participants were sleep-deprived for approximately 24 hr at the start of Session 2.

At 8:45 a.m. the following morning, sleep participants returned and all participants completed Session 2, which included mood and sleepiness assessments, UNRAVEL, and other cognitive tasks associated with the separate experiment. The experiment finished at 10:00 a.m., and deprivation participants were given a ride home.

Deprivation participants failed Session 2 at a greater rate ( n = 18, 15%) than sleep participants ( n = 1, 1%), χ ²(1, N = 234) = 15.04, p < .001. Thus, in some participants, sleep deprivation caused a breakdown in the ability, or perhaps the willingness, to perform the task as instructed, which they had managed to do the previous evening.

In our remaining analyses, we included only participants who passed Session 2 (sleep [ n = 111], deprivation [ n = 104]). We examined sequence errors separately on postinterruption trials (trials immediately following an interruption) and baseline trials (trials following other trials). The two trial types involve identical processing except that postinterruption trials involve recall of the step performed before the interruption, and thus depend on memory maintenance.

Sequence errors are plotted in Figure 2. For postinterruption errors, an analysis of variance (ANOVA) with group (sleep, deprivation) as a between-subjects factor and session (1, 2) and block (1 to 4) as within-subjects factors showed a significant three-way interaction, F(3, 639) = 3.73, p = .011, η ² = .017. To probe the interaction, we analyzed effects of group and block within each session. In Session 1, there was no main effect of group, F(1, 213) = 1.51, p = .221, η ² = .007. There was a main effect of block, F(3, 639) = 9.03, p < .001, η ² = .041, reflecting a practice effect, but no interaction, F(3, 639) = 1.30, p = .275, η ² = .006. Thus, the two groups performed similarly on Session 1, as expected given double-blind administration of the task followed by random assignment to group.

Figure 2. UNRAVEL (where each letter of UNRAVEL identifies a different two-alternative forced-choice decision rule to apply to a randomly generated stimulus) sequence errors: Percentage of postinterruption (solid lines) and baseline (dashed lines) errors made across the four blocks of UNRAVEL in Session 1 (left side) and Session 2 (right side) for the sleep and deprivation groups. Error bars are standard error of the mean.

For postinterruption errors in Session 2, there was a main effect of group, F(1, 213) = 40.76, p < .001, η ² = .161, a main effect of block, F(3, 639) = 13.04, p < .001, η ² = .058, and a significant two-way interaction, F(3, 639) = 7.58, p < .001, η ² = .034. To probe the interaction, we analyzed effects of block within each group. The effect of block was not significant for sleep ( F < 1), but was for deprivation, F(3, 309) = 15.86, p < .001, η ² = .133. In the deprivation group, a polynomial trend analysis indicated a linear increase in errors across blocks, F(1, 103) = 38.53, p < .001, η ² = .272, but no quadratic or cubic trend ( Fs < 1.12, ps > .29). A pairwise comparison showed fewer postinterruption errors in Block 1 than Block 4, t(103) = −6.19, p < .001, d = 0.607, indicating worse performance at the end of the session than at the start. Thus, deprivation participants who passed Session 2 still made more postinterruption errors overall than sleep participants and progressively made more errors across Session 2.

For baseline errors, the Group × Block × Session ANOVA also showed a three-way interaction, F(3, 639) = 3.05, p = .028, η ² = .014. To probe the interaction, we analyzed effects of group and block within each session. In Session 1, there was no main effect of group, F < 1. There was a main effect of block, F(3, 639) = 12.70, p < .001, η ² = .056, reflecting a practice effect, and a marginal interaction, F(3, 639) = 2.37, p = .070, η ² = .011, which we do not attempt to interpret. Thus, on this measure the groups again performed similarly in Session 1.

For baseline errors in Session 2, there were main effects of group, F(1, 213) = 6.96, p = .009, η ² = .032, and block, F(3, 639) = 5.22, p = .001, η ² = .024, but no interaction ( F < 1). The block effect reflects an increase in errors across the session. This increase is relatively small, and did not differ by group, so our interpretation is that the underlying mechanism that caused the increase in errors is not the one that caused the increase in postinterruption errors for the deprivation group. To assess this interpretation statistically, we compared the block effect for postinterruption and baseline errors in the same analysis. A Group × Block × Error Type (postinterruption, baseline) ANOVA for Session 2 showed a significant three-way interaction, F(3, 639) = 6.85, p < .001, η ² = .031. To probe the interaction, we analyzed the Block × Error Type interaction separately for each group. The interaction was not significant for sleep ( F < 1), but was significant for deprivation, F(3, 309) = 12.62, p < .001, η ² = .109. This analysis supports the inference that sleep deprivation had an effect specifically on postinterruption errors, causing them to become more frequent as Session 2 progressed.

In a large sample, we investigated the effects of sleep deprivation on error rates in a procedural task that requires maintenance of task-related information during interruptions. In the evening, sleep and deprivation groups performed similarly. The next morning, a significant proportion of deprivation participants (15%) were unable or unwilling to achieve a modest level of accuracy that they were instructed to achieve and were able to achieve the evening before.

Among those who achieved criterion accuracy, sleep deprivation still impaired performance, in two ways (see Figure 2). First, sleep-deprived participants made more postinterruption and baseline errors, with the effect on postinterruption errors substantially larger (η ² = .161 vs. η ² = .032). Second, sleep-deprived participants made progressively more postinterruption errors across Session 2. The difference in error rates between the first and last block of the session was over half a standard deviation ( d = 0.607). Baseline errors, which are like postinterruption errors except for maintenance failures, did not show the same pattern. Thus, memory maintenance processes became more impaired as Session 2 progressed.

This time-on-task effect resembles that found in sleep-deprived performance on vigilance tasks, but the underlying mechanism seems to be different. In the vigilance context, worsening performance over time has been linked to increasing wake state instability as the homeostatic sleep drive increases ( Doran et al., 2001; Lim & Dinges, 2008). If this mechanism had also been at work in our study, it should have affected overall performance and not just postinterruption errors. Baseline sequence errors increased with time-on-task, but the effect was not large and was similar for both groups, so we assume it was unrelated to sleep deprivation. Accordingly, wake state instability does not seem to have increased over the duration of the session and therefore does not seem to have caused the increase in postinterruption errors.

Instead, the underlying mechanism seems to be related specifically to memory maintenance. Memory maintenance is a complex process with many component mechanisms. As a possible clue to which component was affected, we note that the increase in postinterruption errors across blocks in Session 2 correlates with the number of experienced interruptions. This suggests that the underlying mechanism might be a buildup of proactive interference in episodic memory for past performance. In one theory of cognitive control, specifically this kind of buildup is a primary operational constraint on a system that has to be goal-directed yet be able to change goals ( Altmann & Gray, 2008). In terms of the present results, the implication is that sleep deprivation impairs the mechanisms that manage the buildup of proactive interference. This account is broadly consistent with findings linking sleep deprivation to prefrontal cortex functioning ( Chee & Choo, 2004; Choo et al., 2005; Drummond, Brown, Salamat, & Gillin, 2004; Drummond et al., 1999, 2000; Mu et al., 2005). Procedures used to measure release from proactive interference in list learning (e.g., Wickens, Born, & Allen, 1963) could be adapted to test this account of increasing memory impairments with time-on-task.

From an applied perspective, our results suggest that sleep deprivation can cause a generalized failure to perform a procedural task as instructed, among people who can perform the task successfully when they are not sleep deprived. Whether this breakdown in our participants reflected lack of ability, lack of motivation, or some combination is a critical question to follow up in future work, given that we tested undergraduates participating for course credit rather than professionals performing the tasks they are trained for in high-stakes situations.

Even short of this kind of breakdown, our results suggest that sleep-deprived operators should generally not perform procedural tasks involving interruptions and costly errors-or, if they must, that the assignment should only last for brief periods. If management of proactive interference is the cause, then the density of interruptions or other memory events in time may be more important than the length of time itself. Either way, a more detailed theoretical understanding of this empirical pattern stands to have important implications for the design of systems that may have to accommodate sleep-deprived operators.

This work is a collaborative effort to understand effects of sleep deprivation on procedural error, which is a concern in many workplaces. One of the two laboratories involved develops behavioral tests and cognitive models of goal-directed behavior; the other studies effects of sleep and sleep deprivation on memory and performance. Both take advantage of the statistical power afforded by a large participant pool to answer empirical questions with high reliability. This work is sponsored by the U.S. Navy, which has suffered notable incidents linked to sleep deprived operators making costly procedural errors ( Navy Office of Information, 2017).

The UNRAVEL task was developed to address several challenges associated with studying procedural error ( Altmann et al., 2014). Of relevance here is that the task affords different kinds of error representing failures of different cognitive processes, allowing us to isolate sleep deprivation effects on different processes in a way that seems to be unique in sleep deprivation research. The task also shows promise as a measure of individual differences ( Hambrick & Altmann, 2015; Hambrick, Altmann, & Burgoyne, in press) and in ongoing research we are looking for markers that predict susceptibility to sleep deprivation.

1 Nonsequence errors, and data and statistical tables for all analyses, are presented in the online supplemental material.

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Submitted: May 14, 2018 Revised: July 10, 2018 Accepted: July 18, 2018

This publication is protected by US and international copyright laws and its content may not be copied without the copyright holders express written permission except for the print or download capabilities of the retrieval software used for access. This content is intended solely for the use of the individual user.

Source: Journal of Experimental Psychology: General. Vol. 148. (10), Oct, 2019 pp. 1828-1833)
Accession Number: 2018-47603-001
Digital Object Identifier: 10.1037/xge0000495

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Effects of sleep deprivation on procedural errors

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By: Michelle E. Stepan Department of Psychology, Michigan State University; Kimberly M. Fenn Department of Psychology, Michigan State University Erik M. Altmann Department of Psychology, Michigan State University Acknowledgement: This research was supported by Grant N000141612841 from the Office of Naval Research to Kimberly M. Fenn and Erik M. Altmann.

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The source states that the effects of sleep deprivation include worsening long term memory, decision making and the ability to learn. Continues by saying that sleep deprivation can lead to permanent brain damage which can lead to serious alterations in the daily choices we make. A lack of sleep can also cause us to feel more confident and less cautious than normal while feeling more anxious, restless, irritable, less satisfied. Feeling confident while being sleep deprived was very true for me after nights I spent awake all night doing school work.  Individuals also lose control over their emotions due to sleep deprivation.  So it can be concluded that sleep deprivation can lead to very serious negative effects for an individual in the long term. "Sleep deprivation can over-stimulate parts of the brain and even lead to permanent brain damage."

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Sleep deprivation effects on the brain can be a little harder to identify than the physical effects of sleep deprivation - but make no mistake: sleep deprivation effects relating to the brain may be the most dangerous of all the consequences of lack of sleep.

Sleep deprivation's connection to decreased attention and working memory "is well established," according to the journal Neuropsychiatric Disease and Treatment, "but it also affects other functions, such as long-term memory and decision-making." ¹

At its most basic, effects of lack of sleep on the brain affect "mood and the ability to make memories and learn," Dr. Susan Redline of Brigham and Women's Hospital in Boston told ABC News. ²

At a more advanced level, sleep deprivation can over-stimulate parts of the brain and even lead to permanent brain damage, according to a report on sleep deprivation among students published by The Guardian. ³ "This is because of the brain's 'neural plasticity' - which means its ability to adapt to new situations. When it's forced to operate in a different state on a regular basis, it permanently alters itself."

Well, that's scary, but surely it only affects those who chronically skip sleep - night shift workers, perhaps, or severe sleep apnea sufferers? Not quite. "Our results suggest that just one night of sleep loss significantly alters the optimal functioning of this essential brain process," according to Andrea Goldstein from the Sleep and Neuroimaging Laboratory at the University of California, Berkeley, in the ABC News article.

Among children, sleep deprivation has been linked to "poorer grades, moodiness and depression," reports The New York Times. ⁴ The same article describes the effects of sleep deprivation on teenagers as linked to "poorer grades, moodiness and depression ... those deprived of an hour's sleep performed less well on tests for reaction time, recall and responsiveness than the children who slept the extra hour."

Identifying sleep deprivation effects on the brain

One of the most insidious effects of lack of sleep on the brain is that it can be tough to identify - not only cognitive but emotional issues have been reported, and can lead to conflicting feelings of euphoria and depression.

As the ABC News article explains, imaging of the brain strongly suggests that "sleep deprivation can boost activity in the brain's emotional centers" - meaning that lack of sleep can cause us to feel more confident and less cautious than normal. That's a basic malfunctioning of the brain that can lead to serious repercussions in the daily choices we make.

On the other hand, the link between sleep deprivation and depression is also well established. "People feel more anxious, restless, irritable, less satisfied," Dr. Mark Dyken, director of the University of Iowa's Sleep Disorders Center in Iowa City, is quoted in the ABC News article. "They have difficulty focusing and sometimes feel like they just don't care anymore."

"We found that the emotional center of the brain ... was about 60 percent more active in people who had been sleep deprived, which was quite a frightening amount," said Professor Matt Walker of the University of California, Berkeley, via an article in The Telegraph. ⁵ "As the frontal lobe puts the brakes on the brain's emotional center, it shows that when you're sleep deprived you're all accelerator and no brakes. You don't have control over your emotions."

That's an extreme effect, resulting from extreme sleep deprivation. Most of us don't suffer from that level of sleep loss. All the same, the lessons of sleep deprivation effects on the brain point to a need to try to maintain the recommended level of sleep - six to eight hours each night.

"Sleep is restorative," Dr. Dyken reminds us. "And if you don't get it, your health will suffer."
References

1. Paula Alhola and Päivi Polo-Kantola, "Sleep deprivation: Impact on cognitive performance," Neuropsychiatr Dis Treat. 2007 October; 3(5): 553-567. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656292/ (accessed June 28, 2013).

2. Moisse, Katie. 2012. 5 health hazards linked to lack of sleep. ABC News, June 11, 2012.http://abcnews.go.com/Health/Sleep/health-hazards-linked-lack-sleep/story?id=16524313#.UcyEgDu1HOE (accessed June 28, 2013).

3. Cox, David. 2012. What happens to your body if you don't let it sleep? The Guardian, October 9, 2012.http://www.guardian.co.uk/education/mortarboard/2012/oct/09/students-beware-sleep-deprivation (accessed June 28, 2013).

4. Brody, Jane E. 2007. At every age, feeling the effects of too little sleep. New York Times, October 23, 2007.http://www.nytimes.com/2007/10/23/health/23brod.html (accessed June 28, 2013).

5. Macdonald-Smith, Fiona. 2009. Can sleep deprivation be the cause of mental illness? The Telegraph, March 2, 2009. http://www.telegraph.co.uk/health/4862280/Can-sleep-deprivation-be-the-cause-of-mental-illness.html (accessed June 28, 2013).

This blog post contains general information about medical conditions and treatments. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. The information is not advice, and should not be treated as such. You must not rely on the information on this website as an alternative to medical advice from your doctor or other professional healthcare provider.

If you have any specific questions about any medical matter, you should consult your doctor or other professional healthcare provider. If you think you may be suffering from any medical condition, you should seek immediate medical attention. You should never delay seeking medical advice, disregard medical advice, or discontinue medical treatment because of information on this website. The views expressed on this blog and website have no relation to those of any academic, hospital, practice, or other institution with which the authors are affiliated and do not directly reflect the views of ResMed or any of its subsidiaries or affiliates.

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Sleep deprivation effects on the brain can be a little harder to identify than the physical effects of sleep deprivation - but make no mistake: sleep deprivation effects relating to the brain may be the most dangerous of all the consequences of lack of sleep.

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The reader is informed that just one sleepless night can lead to the creation of a protein implicated in Alzheimer’s in your brain.  The brain uses sleep to get rid of waste which are clumps of misfolded protein, and a lack of sleep turns them toxic. Alzheimer’s disease is associated with the accumulation of such proteins in the human brain. This made me question how the brain actually gets the waste out of the body. The article also stated that there was a study done that showed that sleep deprivation altered connections between the pre-frontal cortex and the part of the brain that deals with emotions.  "Sleep deprived individuals become hypersensitive to rewarding stimuli, emotional responses are heightened, and start acting irrationally."

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Author:
Moheb Costandi, M.Sc.
Published:
July 18, 2018

Sleep is what biologists call a primary biological need, something that no animal can live without, like food and water. The average person spends 25 years, or one third of their lifespan, in this unconscious - and highly vulnerable - state; and yet, the precise function of sleep eludes us.

The past two decades has seen huge leaps in our understanding, however. We now know that sleep plays an important role in learning and memory, with the brain activity patterns associated with newly-acquired information being "replayed" during certain stages of sleep to consolidate it (see " Decoding the Patterns in Sleep" and " The Sleeping Brain ").
Waste disposal
It is also clear that sleep is vital for maintaining good overall brain health, and that prolonged periods of sleep deprivation can have severe consequences. Sleep disturbances are associated with neurodegenerative diseases and psychiatric disorders, so maintaining good sleep hygiene likely reduces one's risk of developing such conditions (see " The Link Between Depression, Sleep, and Stress ").

A new study now shows that just one night of sleep deprivation results in the accumulation in the brain of a protein implicated in Alzheimer's, highlighting once again the importance of good sleep hygiene for brain health.

The brain does most of its housekeeping while we sleep, and one housekeeping duty in particular - waste disposal - seems to be acutely sensitive to a lack of sleep. The brain disposes of its waste via the glymphatic system, which is thought to consist of a network of vessels that runs alongside blood vessels in the scalp and drains waste-filled cerebrospinal fluid from the organ.

Waste products cleared away by this system include insoluble clumps of misfolded proteins that are deposited in the brain; these occur as a normal part of the aging process and also in neurodegenerative diseases. Alzheimer's disease, for example, is associated with the deposition of two such proteins: amyloid-beta, which aggregates to form plaques around brain cells, and tau, which forms tangles inside them.

The finding that the glymphatic system works best while we sleep helps to explain why sleep disturbances are linked to neurodegenerative diseases: Poor sleep hygiene likely reduces the efficiency of the brain's waste disposal system, so that the insoluble protein clumps that would normally be cleared away by it remain in place. Prolonged periods of poor sleep could result in these clumps accumulating to toxic levels, and these, in turn, could worsen sleeping difficulties in a vicious cycle (see " Cleaning the Dirty Brain? ")

We have all had late or sleepless nights, and most of us probably consider this to be completely harmless, even though we know from experience that losing sleep has dramatic effects on our mental abilities and well-being. Sleep deprivation makes us moody and irritable, and impairs brain functions such as memory and decision-making. It also negatively impacts the rest of the body - it impairs the functioning of the immune system, for example, making us more susceptible to infection.

Better brain imaging now enables researchers to examine exactly how sleep deprivation affects brain function. One study, published in 2009, showed that sleep deprivation alters functional connections between the prefrontal cortex and the brain's reward- and emotion-processing centers, impairing so-called executive functions. As a result, we become hypersensitive to rewarding stimuli, our emotional responses are heightened, and we start acting irrationally.

The latest of these studies shows that one night of sleep deprivation results in the deposition of amyloid-beta plaques in parts of the brain that are affected in Alzheimer's. Earlier research had shown that circulating amyloid-beta levels fluctuate with the sleep-wake cycle in mice, and that sleep deprivation significantly increases amyloid-beta levels in the animals' brains, but it was not clear if these findings also apply to humans.

Ehsan Shokri-Kojori of the National Institutes of Health and his colleagues may now have resolved this issue. They injected 20 healthy participants with a radioactive tracer that binds to amyloid-beta, and used positron emission tomography (PET) to see where the tracer was distributed in their brains, once after one night of rested sleep and again after one night of sleep deprivation.

In a paper published in the Proceedings of the National Academy of Sciences, they reported that total amyloid beta levels increased by approximately 5 percent after one night of sleep deprivation, in the right hippocampus and thalamus, both of which are affected early on in Alzheimer's. Furthermore, study participants with the largest increases in amyloid-beta levels also reported worse moods the following day.
A sleep-deprived society?
"We did not determine the extent to which the elevated amyloid levels subside," says Shokri-Kojori, "but it is likely that sleep will clear away these effects, especially when amyloid-beta is in the soluble form."

He adds the caveat that they did not differentiate between the soluble and insoluble forms of the protein, however. "We really don't know whether these changes are lasting, but consistently higher levels of amyloid-beta would likely increase the risk of plaque formation."

Researchers and clinicians now agree that good sleep hygiene is a pillar of the neuroprotective lifestyle, and there is compelling evidence that improving sleep can have huge benefits for overall well-being. One recent study of more than 7,500 British university students showed that digital cognitive behavioral therapy for insomnia not only improved the students' sleep but also reduced the level of delusions and hallucinations they experienced.

"We can now think of sleep as a therapeutic target," says study co-author Russell Foster, director of the Sleep and Circadian Neuroscience Institute at the University of Oxford. "By stabilizing sleep, we actually reduced the severity of their psychiatric symptoms."

The latest findings, presented at the SLEEP 2018 conference in Baltimore in June, show that a daytime lighting intervention improves sleep and mood in Alzheimer's patients, adding more weight to the idea of targeting sleep to treat both psychiatric and neurological conditions.

Yet many remain largely unaware of the importance of sleep. Some experts argue that we live in a sleep-deprived society, in which large sections of the population do not get enough rest or have otherwise unhealthy sleep patterns - including shift workers with irregular schedules and schoolchildren who start their day as early as 7:30 am.

"Sleep is the best cognitive enhancer we've got, but we're doing a very poor job translating this information across to the health community," says Foster, "and it seems extraordinary to me there are no proper educational packages that teach kids about the importance of sleep."

"We don't have longitudinal studies of kids showing poor sleep, so we need to invest in research to resolve unanswered questions. What are these kids' educational outcomes? Can their disrupted sleep be accommodated, or are they suffering long-term health consequences?

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The Sleep-Deprived Brain | Dana Foundation

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Author: Moheb Costandi, M.Sc. Published: July 18, 2018 Sleep is what biologists call a primary biological need, something that no animal can live without, like food and water. The average person spends 25 years, or one third of their lifespan, in this unconscious - and highly vulnerable - state; and yet, the precise function of sleep eludes us.

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According to the article, when a human brain doesn’t receive enough rest for too often, the speed of its brain cells movement slows down dramatically.  The article also referred to a study done at UCLA which showed that as individuals got more and more deprived of sleep, it became more challenging to carry out certain tasks because their brain cells began to slow down.  This slow down of the brain cells in the individuals were being being seen visually by researchers through electrodes attached to their brains. This made me realize why biking to school became a lot harder for me after I spent the entire night before awake. "Sleep deprivation makes it difficult for brain cells to communicate effectively, which can lead to temporary mental lapses that affect memory and visual perception."

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Credit: pathdoc/Shutterstock

After a sleepless night, you likely feel sluggish the next morning, and a small new study suggests why: Your brain cells feel sluggish, too. And when those brain cells are tired, you may be more likely to be forgetful and get distracted more easily, the research found.

In the study, the researchers found that sleep deprivation makes it difficult for brain cells to communicate effectively, which, in turn, can lead to temporary mental lapses that affect memory and visual perception.

In other words, the findings offer clues as to why a sleepless night makes it so hard to think and concentrate the next day. [ The Spooky Effects of Sleep Deprivation]

"We discovered that starving the body of sleep also robs neurons of the ability to function properly," senior study author Dr. Itzhak Fried, a professor of neurosurgery at the University of California, Los Angeles (UCLA), said in a statement. "This paves the way for cognitive lapses in how we perceive and react to the world around us."

To study the effects of sleep deprivation, the researchers recruited 12 patients with epilepsy who, as part of a preparation for surgery unrelated to the study, had electrodes implanted into their brains.These electrodes allowed the researchers to monitor hundreds of individual brain cells.

The people in the study then had to stay up for an entire night. During this time, the researchers measured the participants' brain activity as they carried out certain tasks. For example, the patients were asked to categorize various imagesof faces, places and animalsas fast as possible. Each image caused cells in areas of the brain to produce distinctive patterns of electrical activity. Specifically, the researchers focused on cell activity in the temporal lobe, which regulates visual perception and memory.

The researchers found that as the patients got tired, it became more challenging for them to categorize the images, and their brain cells began to slow down.

"We were fascinated to observe how sleep deprivation dampened brain cell activity," lead study author Yuval Nir, a sleep researcher at Tel Aviv University in Israel, said in the statement. "Unlike the usual rapid reaction, the neurons responded slowly, fired more weakly and their transmissions dragged on longer than usual."

In addition, the researchers found that sleep deprivation affects some areas of the brain more than others. Regions of the brain that experienced sluggish brain cell activity also exhibited brain activity normally seen when a person is asleep, the researchers said.

"This phenomenon suggests that select regions of the patients' brains were dozing, causing mental lapses, while the rest of the brain was awake and running as usual," Fried said.

In addition, the findings suggest that a lack of sleep can interfere with the ability of neurons in the brain to encode information and translate visual input into conscious thought, the researchers said. For example, when a sleep-deprived driver sees a pedestrian stepping in front of his car, it may take longer for the driver to realize what he or she is seeing because "the very act of seeing the pedestrian slows down in the driver's overtired brain," Nir said.

The researchers compared the effects of sleep deprivation to those of drunk driving.

"Inadequate sleep exerts a similar influence on our brain as drinking too much," Fried said. "Yet no legal or medical standards exist for identifying overtired drivers on the road the same way we target drunk drivers."

The study was published yesterday (Nov. 6) in the journal Nature Medicine.

Originally published on Live Science.

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Here's What Happens in the Brain When You Don't Get Enough Sleep

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After a sleepless night, you likely feel sluggish the next morning, and a small new study suggests why: Your brain cells feel sluggish, too. And when those brain cells are tired, you may be more likely to be forgetful and get distracted more easily, the research found.

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According to the article, sleep actually plays a mop up roll by helping clean up toxins that form inside the brain. Adds that long term sleep deprivation can lead to severe illness.  It also stated that Alzheimer’s disease is inheritable from an affected parent. Since this is true, I questioned if children with parents who had Alzheimers, had sleeping problems throughout the early years of their lives.  This article also stated that the lack of sleep can lead to certain disorders, and also that certain diseases cause a lack of sleep.  “Sleep disturbances are common among people with age-related neurological disorders such as Alzheimer’s disease."

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Anatomy of Sleep
Sleep Stages
Sleep mechanisms
How Much Sleep Do You Need?
Dreaming
The Role of Genes and Neurotransmitters
Tracking Sleep Through Smart Technology
Tips for Getting a Good Night's Sleep
Hope Through Research
Where can I get more information?

Introduction

Sleep is an important part of your daily routine-you spend about one-third of your time doing it. Quality sleep - and getting enough of it at the right times -- is as essential to survival as food and water. Without sleep you can't form or maintain the pathways in your brain that let you learn and create new memories, and it's harder to concentrate and respond quickly.

Sleep is important to a number of brain functions, including how nerve cells (neurons) communicate with each other. In fact, your brain and body stay remarkably active while you sleep. Recent findings suggest that sleep plays a housekeeping role that removes toxins in your brain that build up while you are awake.

Everyone needs sleep, but its biological purpose remains a mystery. Sleep affects almost every type of tissue and system in the body - from the brain, heart, and lungs to metabolism, immune function, mood, and disease resistance. Research shows that a chronic lack of sleep, or getting poor quality sleep, increases the risk of disorders including high blood pressure, cardiovascular disease, diabetes, depression, and obesity.

Sleep is a complex and dynamic process that affects how you function in ways scientists are now beginning to understand. This booklet describes how your need for sleep is regulated and what happens in the brain during sleep.

Anatomy of Sleep

Several structures within the brain are involved with sleep.

The hypothalamus, a peanut-sized structure deep inside the brain, contains groups of nerve cells that act as control centers affecting sleep and arousal. Within the hypothalamus is the suprachiasmatic nucleus (SCN) - clusters of thousands of cells that receive information about light exposure directly from the eyes and control your behavioral rhythm. Some people with damage to the SCN sleep erratically throughout the day because they are not able to match their circadian rhythms with the light-dark cycle. Most blind people maintain some ability to sense light and are able to modify their sleep/wake cycle.

The brain stem, at the base of the brain, communicates with the hypothalamus to control the transitions between wake and sleep. (The brain stem includes structures called the pons, medulla, and midbrain.) Sleep-promoting cells within the hypothalamus and the brain stem produce a brain chemical called GABA, which acts to reduce the activity of arousal centers in the hypothalamus and the brain stem. The brain stem (especially the pons and medulla) also plays a special role in REM sleep; it sends signals to relax muscles essential for body posture and limb movements, so that we don't act out our dreams.

The thalamus acts as a relay for information from the senses to the cerebral cortex (the covering of the brain that interprets and processes information from short- to long-term memory). During most stages of sleep, the thalamus becomes quiet, letting you tune out the external world. But during REM sleep, the thalamus is active, sending the cortex images, sounds, and other sensations that fill our dreams.

The pineal gland, located within the brain's two hemispheres, receives signals from the SCN and increases production of the hormone melatonin, which helps put you to sleep once the lights go down. People who have lost their sight and cannot coordinate their natural wake-sleep cycle using natural light can stabilize their sleep patterns by taking small amounts of melatonin at the same time each day. Scientists believe that peaks and valleys of melatonin over time are important for matching the body's circadian rhythm to the external cycle of light and darkness.

The basal forebrain, near the front and bottom of the brain, also promotes sleep and wakefulness, while part of the midbrain acts as an arousal system. Release of adenosine (a chemical by-product of cellular energy consumption) from cells in the basal forebrain and probably other regions supports your sleep drive. Caffeine counteracts sleepiness by blocking the actions of adenosine.

The amygdala, an almond-shaped structure involved in processing emotions, becomes increasingly active during REM sleep.

Sleep Stages

There are two basic types of sleep: rapid eye movement (REM) sleep and non-REM sleep (which has three different stages). Each is linked to specific brain waves and neuronal activity. You cycle through all stages of non-REM and REM sleep several times during a typical night, with increasingly longer, deeper REM periods occurring toward morning.

Stage 1 non-REM sleep is the changeover from wakefulness to sleep. During this short period (lasting several minutes) of relatively light sleep, your heartbeat, breathing, and eye movements slow, and your muscles relax with occasional twitches. Your brain waves begin to slow from their daytime wakefulness patterns.

Stage 2 non-REM sleep is a period of light sleep before you enter deeper sleep. Your heartbeat and breathing slow, and muscles relax even further. Your body temperature drops and eye movements stop. Brain wave activity slows but is marked by brief bursts of electrical activity. You spend more of your repeated sleep cycles in stage 2 sleep than in other sleep stages.

Stage 3 non-REM sleep is the period of deep sleep that you need to feel refreshed in the morning. It occurs in longer periods during the first half of the night. Your heartbeat and breathing slow to their lowest levels during sleep. Your muscles are relaxed and it may be difficult to awaken you. Brain waves become even slower.

REM sleep first occurs about 90 minutes after falling asleep. Your eyes move rapidly from side to side behind closed eyelids. Mixed frequency brain wave activity becomes closer to that seen in wakefulness. Your breathing becomes faster and irregular, and your heart rate and blood pressure increase to near waking levels. Most of your dreaming occurs during REM sleep, although some can also occur in non-REM sleep. Your arm and leg muscles become temporarily paralyzed, which prevents you from acting out your dreams. As you age, you sleep less of your time in REM sleep. Memory consolidation most likely requires both non-REM and REM sleep.

Sleep mechanisms

Two internal biological mechanisms -circadian rhythm and homeostasis-work together to regulate when you are awake and sleep.

Circadian rhythms direct a wide variety of functions from daily fluctuations in wakefulness to body temperature, metabolism, and the release of hormones. They control your timing of sleep and cause you to be sleepy at night and your tendency to wake in the morning without an alarm. Your body's biological clock, which is based on a roughly 24-hour day, controls most circadian rhythms. Circadian rhythms synchronize with environmental cues (light, temperature) about the actual time of day, but they continue even in the absence of cues.

Sleep-wake homeostasis keeps track of your need for sleep. The homeostatic sleep drive reminds the body to sleep after a certain time and regulates sleep intensity. This sleep drive gets stronger every hour you are awake and causes you to sleep longer and more deeply after a period of sleep deprivation.

Factors that influence your sleep-wake needs include medical conditions, medications, stress, sleep environment, and what you eat and drink. Perhaps the greatest influence is the exposure to light. Specialized cells in the retinas of your eyes process light and tell the brain whether it is day or night and can advance or delay our sleep-wake cycle. Exposure to light can make it difficult to fall asleep and return to sleep when awakened.

Night shift workers often have trouble falling asleep when they go to bed, and also have trouble staying awake at work because their natural circadian rhythm and sleep-wake cycle is disrupted. In the case of jet lag, circadian rhythms become out of sync with the time of day when people fly to a different time zone, creating a mismatch between their internal clock and the actual clock.

How Much Sleep Do You Need?

Your need for sleep and your sleep patterns change as you age, but this varies significantly across individuals of the same age. There is no magic "number of sleep hours" that works for everybody of the same age. Babies initially sleep as much as 16 to 18 hours per day, which may boost growth and development (especially of the brain). School-age children and teens on average need about 9.5 hours of sleep per night. Most adults need 7-9 hours of sleep a night, but after age 60, nighttime sleep tends to be shorter, lighter, and interrupted by multiple awakenings. Elderly people are also more likely to take medications that interfere with sleep.

In general, people are getting less sleep than they need due to longer work hours and the availability of round-the-clock entertainment and other activities.

Many people feel they can "catch up" on missed sleep during the weekend but, depending on how sleep-deprived they are, sleeping longer on the weekends may not be adequate.

Dreaming

Everyone dreams. You spend about 2 hours each night dreaming but may not remember most of your dreams. Its exact purpose isn't known, but dreaming may help you process your emotions. Events from the day often invade your thoughts during sleep, and people suffering from stress or anxiety are more likely to have frightening dreams. Dreams can be experienced in all stages of sleep but usually are most vivid in REM sleep. Some people dream in color, while others only recall dreams in black and white.

The Role of Genes and Neurotransmitters
Chemical signals to sleep
Clusters of sleep-promoting neurons in many parts of the brain become more active as we get ready for bed. Nerve-signaling chemicals called neurotransmitters can "switch off" or dampen the activity of cells that signal arousal or relaxation. GABA is associated with sleep, muscle relaxation, and sedation. Norepinephrine and orexin (also called hypocretin) keep some parts of the brain active while we are awake. Other neurotransmitters that shape sleep and wakefulness include acetylcholine, histamine, adrenaline, cortisol, and serotonin.
Genes and sleep
Genes may play a significant role in how much sleep we need. Scientists have identified several genes involved with sleep and sleep disorders, including genes that control the excitability of neurons, and "clock" genes such as Per, tim, and Cry that influence our circadian rhythms and the timing of sleep. Genome-wide association studies have identified sites on various chromosomes that increase our susceptibility to sleep disorders. Also, different genes have been identified with such sleep disorders as familial advanced sleep-phase disorder, narcolepsy, and restless legs syndrome. Some of the genes expressed in the cerebral cortex and other brain areas change their level of expression between sleep and wake. Several genetic models-including the worm, fruit fly, and zebrafish-are helping scientists to identify molecular mechanisms and genetic variants involved in normal sleep and sleep disorders. Additional research will provide better understand of inherited sleep patterns and risks of circadian and sleep disorders.
Sleep studies
Your health care provider may recommend a polysomnogram or other test to diagnose a sleep disorder. A polysomnogram typically involves spending the night at a sleep lab or sleep center. It records your breathing, oxygen levels, eye and limb movements, heart rate, and brain waves throughout the night. Your sleep is also video and audio recorded. The data can help a sleep specialist determine if you are reaching and proceeding properly through the various sleep stages. Results may be used to develop a treatment plan or determine if further tests are needed.

Tracking Sleep Through Smart Technology

Millions of people are using smartphone apps, bedside monitors, and wearable items (including bracelets, smart watches, and headbands) to informally collect and analyze data about their sleep. Smart technology can record sounds and movement during sleep, journal hours slept, and monitor heart beat and respiration. Using a companion app, data from some devices can be synced to a smartphone or tablet, or uploaded to a PC. Other apps and devices make white noise, produce light that stimulates melatonin production, and use gentle vibrations to help us sleep and wake.

Tips for Getting a Good Night's Sleep

Getting enough sleep is good for your health. Here are a few tips to improve your sleep:

Set a schedule - go to bed and wake up at the same time each day.

Exercise 20 to 30 minutes a day but no later than a few hours before going to bed.

Avoid caffeine and nicotine late in the day and alcoholic drinks before bed.

Relax before bed - try a warm bath, reading, or another relaxing routine.

Create a room for sleep - avoid bright lights and loud sounds, keep the room at a comfortable temperature, and don't watch TV or have a computer in your bedroom.

Don't lie in bed awake. If you can't get to sleep, do something else, like reading or listening to music, until you feel tired.

See a doctor if you have a problem sleeping or if you feel unusually tired during the day. Most sleep disorders can be treated effectively.

Hope Through Research

Scientists continue to learn about the function and regulation of sleep. A key focus of research is to understand the risks involved with being chronically sleep deprived and the relationship between sleep and disease. People who are chronically sleep deprived are more likely to be overweight, have strokes and cardiovascular disease, infections, and certain types of cancer than those who get enough sleep. Sleep disturbances are common among people with age-related neurological disorders such as Alzheimer's disease and Parkinson's disease. Many mysteries remain about the association between sleep and these health problems. Does the lack of sleep lead to certain disorders, or do certain diseases cause a lack of sleep? These, and many other questions about sleep, represent the frontier of sleep research.

Where Can I Get More Information?

For information on other neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute's Brain Resources and Information Network (BRAIN) at:

BRAIN
P.O. Box 5801
Bethesda, MD 20824
(800) 352-9424
www.ninds.nih.gov

Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892

NIH Publication No. 17-3440c

NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.

All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.

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Anatomy of Sleep Sleep Stages Sleep mechanisms How Much Sleep Do You Need? Dreaming The Role of Genes and Neurotransmitters Tracking Sleep Through Smart Technology Tips for Getting a Good Night's Sleep Hope Through Research Where can I get more information?

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David Eagleman writes that in order to fulfill a need or to satisfy itself, the brain can create fake memories. The brain will create a memory of an event that never even happened, in order to get off with a task or to attain self fulfillment.  It can be concluded that depriving the brain of sleep can lead to not only memory loss, which is the most common thought of effect, it can even cause the formation of fake memories that are used to satisfy the individual which makes me wonder why this even happens. “No one is having an experience of the objective reality that really exists; each creature perceives only what it has evolved to perceive."

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Read 1,725 reviews from the world's largest community for readers. Locked in the silence and darkness of your skull, your brain fashions the rich narrative...