User:Shanehyde10/sandbox

SHANE HYDE AND PETER GAFFNEY

SLEEP INERTIA WIKIPEDIA EDIT PROJECT : HUMAN PHYSIOLOGY FORDHAM UNIVERSITY

For the physiology wikipedia project for the Spring 2017 semester, I have chosen to review/edit the article on Sleep Inertia.

Prior to reviewing the article, it holds standing as a start class of mid-importance in the scope of WikiProject Physiology.

I believe that the article can be improved, for it is very brief and seemingly undeveloped in its structure. The article only contains 2 sub-headings, and only 11 references. After a background literature search on the topic, it appears that review papers are not entirely abundant, however there is sufficient material on the web to ad to the article.

Organizationally, the article can be headed differently than the mere factors and causes. Within the factors section, there can be a subdivision

Factors:

adenosine

glucose/glucagon

caffeine

Measures:

KSS

definition of grogginess

how it has been measured throughout the literature

**************************HERE IS THE ORIGINAL ARTICLE PRIOR TO OUR EDITING************************************

Sleep inertia is a physiological state characterised by a decline in motor dexterity and a subjective feeling of grogginess immediately following an abrupt awakening. The impaired alertness may interfere with the ability to perform mental or physical tasks. Sleep inertia can also refer to the tendency of a person wanting to return to sleep.

Sleep inertia occurs normally after awakening. Upon awakening in the morning, subjective alertness and mental performance are significantly impaired. Morning sleep inertia may take several hours to dissipate. In the majority of cases, morning sleep inertia is experienced for 15 to 30 minutes after waking.

[At first glance, the intro may be a bit wordy, especially with the repetition of the word "awakening" and the use of "grogginess". These simple aesthetic changes may improve the presentation of the article as a whole.]

Factors[edit | edit source]

[The usage of factors as a heading is ambiguous and features too much overlap with causes, especially in the presentation of this article. We plan to remove factors as a heading, and rather use symptoms. This section will be limited to only the symptoms of sleep inertia, aside from what has caused these symptoms physiologically, and potential ways to alleviate these symptoms]

Studies by the Human Factors Division at NASA Ames Research Center have shown that a variety of factors influence the severity and duration of sleep inertia.These include:

[The statement above implies that NASA Ames Research Center is the only research center responsible for sleep inertia research. In reality the research into this topic expands much further, and this claim should not be used in the heading.]

• Depth of sleep when awakened. After roughly 10–30 minutes, the brain enters into slow-wave sleep [6]. Being awakened during this stage yields more sleep inertia than awakening from other stages of sleep.

[The citation in the above statement (not present here) is from an expired webpage and must be removed.]

• Timing of sleep. Sleep inertia is thought to be related to the phase of the body's circadian rhythm. Sleep inertia in terms of a serial addition task had a strong circadian rhythm. "Sleep inertia is the impaired cognitive performance immediately upon awakening, which decays over tens of minutes. This phenomenon has relevance to people who need to make important decisions soon after awakening, such as on-call emergency workers."

[Further research expressed the conflicting factors between circadian rhythm and sleep studies, and

• Chemical influences. Drugs such as caffeine can suppress the effect of sleep inertia, possibly by blocking adenosine receptors in the brain. Sustained low-dose caffeine was examined as a sleep inertia countermeasure during the last 66 hours of an 88-hour period of wakefulness that included seven two-hour naps. Lapses in attention were examined after awakening from naps. Performance was impaired significantly in the placebo condition but not with caffeine, and caffeine had only modest effects on nap sleep structure.

[The statement crossed out above contains merely a summary of a primary article. Primary research should not be used in Wikipedia articles and the findings from this single study may not be entirely replicable. Information from this source has been found within an existing review article and will be replaced with findings from the review.]

Reaction time performance is directly related to sleep stage at awakening; persons awakened during the deepest sleep have the slowest reaction times.

Testing of mental arithmetic capability after one- and two hour naps at all times of day and night and after varying amounts of sleep and sleep deprivation demonstrated an inertia characterized by social interaction but with simultaneous performance impairment, reverie and misjudgment of sleepiness.

Cause[edit | edit source]

One theory is that sleep inertia is caused by the build-up of adenosine in the brain during NREM sleep. Adenosine then binds to receptors, and feelings of tiredness result. Sleep inertia may also be the result of lower levels of glucose being available than during wakefulness - The gradual dissipation of sleep inertia could be attributed to the effects of Glucagon on Glycogen shortly after awakening, and the gradual increase in blood glucose to a normal level, assisted and achieved by eating as well.^{[citation needed]}

See also[edit | edit source]

• Circadian rhythm sleep disorder
• Delayed sleep phase syndrome
• Shift work

********************************************************END ORIGINAL ARTICLE*********************************************************************************

We plan to rearrange the article into 3 subheadings, which would rearrange the current order and layout of information. The original article contains only two subheading, factors and causes, and the content appears to overlap between the two. There is no distinct border separating, so we propose to break it down into signs/symptoms and causes instead. This will separate the features of sleep inertia from the physiological mechanisms that are causing it. We also propose to include a third section on the diagnosis or measurement of sleep inertia, and any possible pathophysiology that might be related to sleep inertia. The next step is to look into these sub-heading further and support the article with new references.

Additional Source: "THE SLEEP INERTIA PHENOMENON DURING THE SLEEP-WAKE TRANSITION: THEORETICAL AND OPERATIONAL ISSUES"

Ferrera, Michele and de Gennaro, Luigi Published: 2000

> Immediately after waking there are still remnants of slow-wave sleep, as shown by a gradual decline in delta/theta power shown by Fast-Fourier Transformation of EEG signals, and carry-over of SWS components in a subset of individuals shown by visual-evoked potentials

>Cerebral blood flow velocity may take up to 30 minutes to return to waking state levels, indicative of uncoupled cerebral electrical and vascular activity and retardation of physiological onset of wakefulness

>Sleep inertia has been shown to exhibit its effects in an asymptotic fashion, with its strongest effects apparent immediately upon waking followed by a sharp decline

>awakenings during slow wave sleep have been shown to impair performance on simple-motor, sensory-motor, and cognitive tasks

>Sleep deprivation leads to a greater duration of slow wave sleep. Consequentially, prior sleep deprivation was shown to potentiate the effects of sleep inertia and the associated cognitive impairment

>Highly demanding cognitive tasks are more greatly impaired as compared to simple motor tasks (may be due to the attentional load). More specifically, the accuracy of the subject's abilities is far more effected than the speed

Additional Source: "TIME TO WAKE UP: REACTIVE COUNTERMEASURES TO SLEEP INERTIA"

Hilditch, C., Dorrian, J., and Banks, S. Published: 2016

**NOTE: this review directly addresses strategies to combat the effects of sleep inertia. Some of these strategies elucidate mechanisms of sleep inertia, however much of this material can be included in the final section on diagnosis/alleviation of symptoms

>one testing method is psychomotor vigilance task (PVT) which measures reaction time and attentiveness of subject

>sustained low-dose caffeine (one quarter cup coffee every hour) alleviated some effects of sleep inertia. However important to note administration of coffee was given before the actual sleeping period. When administered following sleep, caffeine gum did indeed improve PVT performance, however effects took from 12-18 minutes post-sleep to set in

>light was shown in several studies to improve subjective sleepiness, however not motor/cognitive parameter improvements were shown across the board. One study however did find that dawn simulation with strong light did show performance benefits on tasks. This review describes the Cortisol Awakening Response (CAR) with reference to light, mentioning lower levels of cortisol during the deep stages of sleep, followed by a spike upon awakening. CAR was potentiated by the greater presence of light upon awakening.

>Both sound and temperature were studied with relation to sleep inertia, however the authors are hesitant to make gross claims about either. Reduction in subjective sleepiness was correlated to a decrease in distal-proximal skin temperature gradient (DPG), and the implementation of light accelerated this decrease in DPG, however there was no interaction effects on the objective parameters of sleep inertia. Spatial memory was impaired immediately following a nap compared to a no-nap condition, and a nap+noise condition appeared to reverse these effects.

>self-awakening vs. forced awakening expressed greater attentiveness at the 15 minute mark, however no later improvements following this benchmark were observed

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Addition of new sub-heading : Treatments/Countermeasures

(since all material is newly written, all font will be in bold-face)

Treatments/Countermeasures

There has been a great deal of research into potential methods to relieve the effects of sleep inertia. The demand for remedies is driven by the occupational hazards of sleep inertia for employees who work extended shifts such as medical professionals, emergency responders, or military personnel. The motor functioning and cognitive ability of these professionals who must immediately respond to a call can pose a safety hazard in the workplace. Below are some of the various conditions that have been suggested to combat sleep inertia.

Napping

When sleep deprived, re-entering sleep may provide a viable route to reduce mental and physical fatigue but this can also induce sleep inertia. In order to limit sleep inertia, one should avert from waking in the deeper stages of slow-wave sleep. The onset of slow-wave sleep occurs approximately 30 minutes after falling asleep, therefore a nap should be limited to under 25 minutes to reduce the effects of sleep inertia upon waking . Furthermore, self-awakening from a short nap was shown to relieve disorientation of sleep inertia as opposed to a forced awakening but these results may warrant more research into the nature of arousal after sleep periods .

Caffeine

Caffeine is a xanthine derivative that can cross the blood-brain barrier. The caffeine present in coffee or tea exerts its stimulating action by blocking adenosine receptors in the brain. By antagonizing the adenosine receptors caffeine limits the effects of adenosine buildup in the brain and increases alertness and attentiveness. Previous research has shown that coupled with a short nap, the proactive administration of caffeine prior to the nap can alleviate the effects of sleep inertia . Nonetheless, individual degree of consumption and tolerance to caffeine may be responsible for variation in its efficacy to reduce sleep inertia symptoms.

Light

The natural light provided by the morning sunrise may be attributed to sleep inertia effects. Research simulating increase of light at dawn was shown to potentiate the Cortisol Awakening Response (CAR) . The CAR is a spike in blood cortisol levels following awakening, and is associated with the return to an alert cognitive state.

Other

Some other potential stimuli that could potentially minimized the effects of sleep inertia are sound and temperature. There is moderate evidence that the presence of mild sounds, and a sharp decrease in body temperature may independently reverse sleep inertia symptoms . Noise is thought to increase the attentiveness of an individual upon awakening. A drop in temperature of the proximities may prevent heat loss, facilitating the return of core-body temperature to homeostatic daytime levels.

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Edits below address the symptoms heading. This heading will likely be short, since much of the physiological mechanisms are described in the symptoms and treatments sections.

Symptoms

• grogginess
• impaired motor dexterity
• decreased reaction time
• decreased cognitive functioning (PVT)
• *upon awakening for the first 20-45 minutes
• "Grogginess", as defined by a drowsy or disoriented state in which there is a dampening of sensory acuity and mental processing.
• Impaired motor dexterity and decrease in cognitive ability. These gross impairments may be responsible for the associated increase in reaction time and drop in attentiveness.
• Deficits in spatial memory
• Reports of heightened subjective fatigue

These symptoms are expressed with the greatest intensity immediately after waking, and disseminate following a period extended wakefulness. The duration of symptoms varies on a conditional basis, with primary expression during the first 15-60 minutes after waking and potentially extending for several hours . Tasks that require more complex cognitive operations will feature greater deficits as compared to a simple motor task; the accuracy of sensory and motor functioning is more impaired by sleep inertia as compared to sheer speed (cite). In order to measure the cognitive and motor deficiencies associated with sleep inertia, a battery of tests may be utilized including psychomotor vigilance task, descending subtraction task, auditory reaction time task, and the finger tapping task (cite,cite).