This research was funded by the Intramural Research Program of the NIMH (ZIA MH00889). RMS was also supported by a FRAXA Postdoctoral Fellowship.

NOTE: All the procedures were approved by the National Institute of Mental Health Animal Care and Use Committee and performed in accordance with the National Institutes of Health Guidelines on the Care and Use of Animals.
1. Sleep Deprivation Setup
<ol>
	<li>Use soft paintbrushes to gently poke mice when asleep.
	<ol>
		<li>Make sure the paintbrush can fit through the bars of the mouse cage feeder to ensure that mice have access to food and water ad libitum during sleep deprivation.</li>
		<li>Do not use paintbrushes for multiple cages to prevent the transfer of scents between cages. We suggest that you label each brush with its assigned cage and restrict its use to that cage.</li>
	</ol>
	</li>
	<li>Designate a room where all sleep deprivation will occur.</li>
</ol>
2. Animal Setup
<ol>
	<li>Randomly assign each cage to either sleep deprivation or control group.</li>
	<li>Give mice access to food and water ad libitum during the experiment.</li>
	<li>Make sure view of mice is not restricted by bedding, nest material, or enrichment objects in cage.
	<ol>
		<li>Remove extra bedding or enrichment objects that could restrict the view of the mice.</li>
	</ol>
	</li>
	<li>If food or water restricts view of mice, move mice to an area of cage where the view is not restricted.
	<ol>
		<li>If the food blocks a large portion of the cage, remove some food and place pellets at the bottom of the cage so that animals maintain access to food during the sleep deprivation period.</li>
	</ol>
	</li>
</ol>
3. Animal Conditions
NOTE: We chose to begin the three hour sleep deprivation period at 11 AM, when mice are in the middle of their inactive phase, but the time of day and duration of sleep deprivation can be chosen based on the desired experimental conditions.
<ol>
	<li>Control Group.
	<ol>
		<li>On P5, remove the sire from the breeder cage and leave the dam with the pups until weaning (P21).</li>
		<li>Move mice assigned to the control group to the sleep deprivation room and gently prod the mice with a paint brush continuously for 10 minutes a day for the duration of the experiment (P5 to P42).</li>
		<li>After these 10 minutes, return the mice to the animal holding room and do not disturb them</li>
	</ol>
	</li>
	<li>Sleep Deprivation Group.
	<ol>
		<li>On P5, remove the sire from the breeder cage and leave the dam with the pups until weaning (P21). 
		NOTE: Sleep deprivation prior to P5 may result in cannibalization of the pups. We did not observe significant cannibalization at P5 and later. 
		NOTE: In young pups, the drive to sleep is very high requiring almost constant stroking. As the mice develop, especially after weaning, the sleep pressure is lower and they do not need constant prodding.</li>
		<li>Continue with sleep deprivation every day until P42. 
		NOTE: Sleep deprivation protocols can vary in length and extend past P42 if desired.</li>
		<li>Move mice assigned to the sleep deprivation group to the sleep deprivation room daily during the light cycle where they will be monitored. The exact duration of sleep deprivation can be adjusted based on the specific research question. 
		NOTE: In neonatal mice sleep deprivation that lasts longer than 3 hours is difficult because of the increase in sleep pressure15.
		<ol>
			<li>During this time, gently prod the mice with the paintbrush any time that sleep is evident. Specifics of sleep deprivation are explained in the next section.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
4. Sleep Deprivation
<ol>
	<li>Gently prod mouse with paintbrush if suspected of being asleep until a response is observed. Alternatively, invert mice and push over onto their backs to disrupt sleep.
	<ol>
		<li>Consider a mouse to be asleep if any of the following occur: inactivity, twitching (especially with pups), or if their eyes are closed (in mice older than P12).</li>
		<li>Consider mice to be awake if they are moving around, trying to flip over after being on their backs, or grooming themselves.</li>
	</ol>
	</li>
	<li>If dam is covering pups during sleep deprivation, gently prod her away from pups so the view of the pups is unrestricted.</li>
</ol>
5. After Sleep Deprivation
<ol>
	<li>When the three-hour period of sleep deprivation is complete, put the bedding and any food that may have been removed back and put the lid back on the cage.</li>
	<li>Return cages to animal holding room until the next day of sleep deprivation.</li>
</ol>
6. Subsequent Experiments
<ol>
	<li>Depending on the goal of the sleep deprivation study, proceed with subsequent experiments.
	<ol>
		<li>Harvest serum from animals to determine corticosterone levels18.</li>
		<li>Do any of a number of behavioral tests, including Open field, RotaRod, Elevated Plus Maze, Social behavior testing, Marble Burying, etc.8,19,20 These behavior tests will also prevent the animals from sleeping so that should be factored in when determining how many days of continuous sleep deprivation to employ.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose.

Here we describe a method for sleep deprivation, gentle handling, that can be used in both rodent pups and in adults. Gentle handing requires researchers to observe mice for the duration of a sleep deprivation period and gently prod the animals whenever they are inactive or twitching to prevent sleep. Prior sleep deprivation studies have verified by means of simultaneous electroencephalogram (EEG) recordings that gentle handling prevents both REM and non-REM (NREM) sleep10. While gentle handling i...

Sleep plays a critical role in neuronal plasticity and synapse formation and elimination during brain development1,2. Specifically, rapid eye movement (REM) sleep is essential for forming stable synaptic circuits through both strengthening of specific synapses and synaptic pruning2. Pharmacological sleep deprivation early in life leads to many physiological and behavioral deficits3,4. In addition to pharmacological sleep deprivation, other forms of sleep deprivation such as constant shaking, forced locomotion, or presentation of an aversive stimulus have been associated with depression-like symptoms during adulthood, different neural activation patterns, and changes in sleep time and sleep continuity during a recovery period following deprivation5,6,7. When sleep is chronically restricted in mice for over five weeks during development, behavioral deficits were observed following a month of sleep recovery8. Taken together, these studies suggest that disruption of sleep in the neonatal rodent can affect later sleep patterns, brain function, and behavior. Highlighting the importance of sleep for normal brain development in humans, many patients with neurodevelopmental disorders, including Autism Spectrum Disorders, Tuberous Sclerosis Complex, Fragile X Syndrome, and Attention-Deficit/Hyperactivity Disorder, report abnormalities in sleep patterns in addition to a variety of behavioral deficits1.
Given the number of neurodevelopmental disorders that are associated with abnormal sleep patterns, it is important to understand how lack of sleep affects brain function and behavior. However, despite the data that support the importance of sleep during development, most methodologies that restrict or deprive animals of sleep focus on adults. These techniques include a variety of tests that require forced locomotor activity (e.g., constant treadmill), constant disruption (e.g., rotating sweeper bar or continual novel object presentation), or disturbing the animal at the onset of REM sleep (e.g., platform over water)9,10. Although these methods have effectively shown the problems associated with sleep deprivation in adults, none of these methods are appropriate for rodent pups because of their limited mobility, high sleep drive, and the adverse effects of stress early in life. Due to the importance of sleep during development, it is critical to understand how restricted sleep in neonatal pups affects future behavior during adulthood.
One technique to restrict sleep that can be used in rodent pups is gentle handling. Gentle handling involves the investigator directly interacting with the rodents any time sleep behavior is observed. Investigators can use their hands, a paintbrush, or presentation of novel objects to physically disrupt sleep in neonatal rodents8,10,11,12,13,14. Sleep can be behaviorally determined by lack of motor activity, myoclonic twitching, and eye closure (in older rodent pups). EEG validation confirms that disrupting sleep with gentle handling based on these behaviors reduces total sleep time by 91% in P12 rats14. Other techniques that have been used to deprive young mice include electric shock and presentation of unpleasant stimuli, but these techniques cannot be used for chronic sleep restriction and are more stressful than gentle handling7,15. Chronic sleep restriction can also be accomplished through a shaking protocol that can be used with or without EEG electrode implantation and associated computer software, but this protocol does not prevent all sleep and therefore is less controlled compared to gentle handling4,16. The ability to restrict or deprive mice of sleep for many days in a row without specific equipment, computer software, or electrode implantation is a benefit of the gentle handling technique. Chronic sleep restriction via gentle handling effectively limits sleep in neonatal rodents and produces a variety of behavioral changes following the sleep deprivation period8,11,12,17.
Here, we describe results in which chronic sleep deprivation for three hours per day from postnatal day 5 (P5) to P42 significantly affects sociability of mice following a 30-day recovery period in which sleep is not disturbed. These results highlight the long-term effects of chronic sleep restriction during development on future behavior.

<table>
	<tbody>
		<tr>
			<td>C57BL/6J mice</td>
			<td>Jackson Labs</td>
			<td>000664</td>
			<td>Wildtype mice used</td>
		</tr>
		<tr>
			<td>Super Mouse 750 Mouse Cage</td>
			<td>Lab Products, Inc.&#160;</td>
			<td></td>
			<td>Cages for the mice</td>
		</tr>
		<tr>
			<td>SANI-Chips Bedding</td>
			<td>PJ Murphys</td>
			<td></td>
			<td>Bedding for the mice</td>
		</tr>
		<tr>
			<td>S&#38;S Bristle Brush Assortment Pack</td>
			<td>Staples</td>
			<td>Item # 13764, Model AB37100</td>
			<td>Paint brushes are used to gently poke mice</td>
		</tr>
	</tbody>
</table>

chronic sleep deprivation in mouse pups by means of gentle handling

Sleep is critical for proper development and neural plasticity. Moreover, abnormal sleep patterns are characteristic of many neurodevelopmental disorders. Studying how chronic sleep restriction during development can affect adult behavior may add to our understanding of the emergence of behavioral symptoms of neurodevelopmental disorders. While there are many methods that can be used to restrict sleep in rodents including forced locomotion, constant disruption, presentation of an aversive stimulus, or electric shock, many of these methods are very stressful and cannot be used in neonatal mice. Here, we describe gentle handling, a sleep deprivation technique that can be used chronically throughout development and into adulthood to achieve sleep restriction. Gentle handling involves close observation of the mice throughout the sleep deprivation period and requires the researcher to gently prod the animals whenever they are inactive or display behaviors associated with sleep. Coupled with EEG recordings, gentle handling could be used to selectively disrupt a specific phase of sleep such as rapid eye movement (REM) sleep. The technique of gentle handling is a powerful tool for the study of the effects of chronic sleep restriction even in neonatal mice that circumvents many of the more stressful procedures used for sleep deprivation.

To investigate the effects of chronic sleep restriction on behavior, we sleep restricted mice for three hours daily between 11:00 AM and 2:00 PM from P5 to P428. Following the sleep restriction, mice were left undisturbed for four weeks and allowed to recover from sleep restriction. Mice were tested for behavior following the four-week recovery period. The three-chamber social behavior test was used to assess sociability (preference for a novel mouse compared to a ...

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Chronic Sleep Deprivation in Mouse Pups by Means of Gentle Handling

We describe a sleep deprivation technique known as gentle handling where investigators gently prod mice any time sleep behavior is observed. This method is a powerful tool that allows researchers to study the effects that chronic sleep restriction throughout development can have on future brain physiology and behavior.

Sleep is critical for proper development and neural plasticity. Moreover, abnormal sleep patterns are characteristic of many neurodevelopmental disorders. ...

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9.9K Views.  National Institutes of Health. We describe a sleep deprivation technique known as gentle handling where investigators gently prod mice any time sleep behavior is observed. This method is a powerful tool that allows researchers to study the effects that chronic sleep restriction throughout development can have on future brain physiology and behavior.

Video: Chronic Sleep Deprivation in Mouse Pups by Means of Gentle Handling

The Crossmodal Congruency Task as a Means to Obtain an Objective Behavioral Measure in the Rubber Hand Illusion Paradigm

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden hand is touched. If the viewed and felt touches are given at the same time then this is sufficient to induce the compelling experience that the rubber hand is one's own hand. The RHI can be used to investigate exactly how the brain constructs distinct body representations for one's own body. Such representations are crucial for successful interactions with the external world. To obtain a subjective measure of the RHI, researchers typically ask participants to rate statements such as "I felt as if the rubber hand were my hand". Here we demonstrate how the crossmodal congruency task can be used to obtain an objective behavioral measure within this paradigm.
The variant of the crossmodal congruency task we employ involves the presentation of tactile targets and visual distractors. Targets and distractors are spatially congruent (i.e. same finger) on some trials and incongruent (i.e. different finger) on others. The difference in performance between incongruent and congruent trials - the crossmodal congruency effect (CCE) - indexes multisensory interactions. Importantly, the CCE is modulated both by viewing a hand as well as the synchrony of viewed and felt touch which are both crucial factors for the RHI.
The use of the crossmodal congruency task within the RHI paradigm has several advantages. It is a simple behavioral measure which can be repeated many times and which can be obtained during the illusion while participants view the artificial hand. Furthermore, this measure is not susceptible to observer and experimenter biases. The combination of the RHI paradigm with the crossmodal congruency task allows in particular for the investigation of multisensory processes which are critical for modulations of body representations as in the RHI.

We demonstrate how an objective measure can be employed in the widely employed rubber hand illusion paradigm. This measure is obtained by modifying the well-established crossmodal congruency task. This task allows the investigation of multisensory processes which are critical for modulations of body representations as in the rubber hand illusion.

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden ...

The Use of the Puzzle Box as a Means of Assessing the Efficacy of Environmental Enrichment

Environmental enrichment can dramatically influence the development and function of neural circuits. Further, enrichment has been shown to successfully delay the onset of symptoms in models of Huntington&#8217;s disease 1-4, suggesting environmental factors can evoke a neuroprotective effect against the progressive, cellular level damage observed in neurodegenerative disorders. The ways in which an animal can be environmentally enriched, however, can vary considerably. Further, there is no straightforward manner in which the effects of environmental enrichment can be assessed: most methods require either fairly complicated behavioral paradigms and/or postmortem anatomical/physiological analyses. This protocol describes the use of a simple and inexpensive behavioral assay, the Puzzle Box 5-7 as a robust means of determining the efficacy of increased social, sensory and motor stimulation on mice compared to cohorts raised in standard laboratory conditions. This simple problem solving task takes advantage of a rodent&#8217;s innate desire to avoid open enclosures by seeking shelter. Cognitive ability is assessed by adding increasingly complex impediments to the shelter&#8217;s entrance. The time a given subject takes to successfully remove the obstructions and enter the shelter serves as the primary metric for task performance. This method could provide a reliable means of rapidly assessing the efficacy of different enrichment protocols on cognitive function, thus paving the way for systematically determining the role specific environmental factors play in delaying the onset of neurodevelopmental and neurodegenerative disease.

Environmental enrichment provides a potential protective effect against neurodegenerative disorders. Currently, however, there is no easy way of determining the efficacy of enrichment procedures. This protocol describes a simple &#8220;Puzzle Box&#8221; method for assessing an animal&#8217;s cognitive function, in order to reveal the effectiveness of environmental enrichment.

Environmental enrichment can dramatically influence the development and function of neural circuits.  Further, enrichment has been shown to successfully ...

Errors as a Means of Reducing Impulsive Food Choice

Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ultimately, to reduced life expectancy. The capacity to refrain from automatic responses is usually high in situations in which making errors is highly likely. The protocol described here aims at reducing imprudent preference in women during hypothetical intertemporal choices about appetitive food by associating it with errors. First, participants undergo an error task where two different edible stimuli are associated with two different error likelihoods (high and low). Second, they make intertemporal choices about the two edible stimuli, separately. As a result, this method decreases the discount rate for future amounts of the edible reward that cued higher error likelihood, selectively. This effect is under the influence of the self-reported hunger level. The present protocol demonstrates that errors, well known as motivationally salient events, can induce the recruitment of cognitive control, thus being ultimately useful in reducing impatient choices for edible commodities.

Giving in to temptation of tasty food may result in long-term overweight problems. This protocol describes how to reduce imprudent preference for edible commodities during hypothetical intertemporal choices in women by associating them with errors.

Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ...

Manipulation of Epileptiform Electrocorticograms (ECoGs) and Sleep in Rats and Mice by Acupuncture

Ancient Chinese literature has documented that acupuncture possesses efficient therapeutic effects on epilepsy and insomnia. There is, however, little research to reveal the possible mechanisms behind these effects. To investigate the effect of acupuncture on epilepsy and sleep, several issues need to be addressed. The first is to identify the acupoints, which correspond between humans, rats, and mice. Furthermore, the depth of insertion of the acupuncture needle, the degree of needle twist in manual needle acupuncture, and the stimulation parameters for electroacupuncture (EA) need to be determined. To evaluate the effects of acupuncture on epilepsy and sleep, a feasible model of epilepsy in rodents is required. We administer pilocarpine into the left central nucleus of the amygdala (CeA) to simulate focal temporal lobe epilepsy (TLE) in rats. Intraperitoneal (IP) injection of pilocarpine induces generalized epilepsy and status epilepticus (SE) in rats. Five IP injections of pentylenetetrazol (PTZ) with a one-day interval between each injection successfully induces spontaneous generalized epilepsy in mice. Recordings of electrocorticograms (ECoGs), electromyograms (EMGs), brain temperature, and locomotor activity are used for sleep analysis in rats, while ECoGs, EMGs, and locomotor activity are employed for sleep analysis in mice. ECoG electrodes are implanted into the frontal, parietal, and contralateral occipital cortices, and a thermistor is implanted above the cerebral cortex by stereotactic surgery. EMG electrodes are implanted into the neck muscles, and an infrared detector determines locomotor activity. The criteria for categorizing vigilance stages, including wakefulness, rapid eye movement (REM) sleep, and non-REM (NREM) sleep are based on information from ECoGs, EMGs, brain temperature, and locomotor activity. Detailed classification criteria are stated in the text.

Manipulation of Epileptiform Electrocorticograms ECoGs and Sleep in Rats and Mice by Acupuncture

This paper demonstrates the performance of acupuncture, epilepsy models, and the analysis of sleep in rodents. The acupuncture procedure and the identification of acupoints are described. Pilocarpine or pentylenetetrazol (PTZ) is used to induce epilepsy. Electrocorticogram (ECoG), electromyogram (EMG), brain temperature, and locomotor activity recordings are employed for sleep analysis.

Ancient Chinese literature has documented that acupuncture possesses efficient therapeutic effects on epilepsy and insomnia. There is, however, little ...

Neurodevelopmental Reflex Testing in Neonatal Rat Pups

Neurodevelopmental reflex testing is commonly used in clinical practice to assess the maturation of the nervous system. Neurodevelopmental reflexes are also referred to as primitive reflexes. They are sensitive and consistent with later outcomes. Abnormal reflexes are described as an absence, persistence, reappearance, or latency of reflexes, which are predictive indices of infants that are at high risk for neurodevelopmental disorders. Animal models of neurodevelopmental disabilities, such as cerebral palsy, often display aberrant developmental reflexes, as would be observed in human infants. The techniques described assess a variety of neurodevelopmental reflexes in neonatal rats. Neurodevelopmental reflex testing offers the investigator a testing method that is not otherwise available in such young animals. The methodology presented here aims to assist investigators in examining developmental milestones in neonatal rats as a method of detecting early-onset brain injury and/or determining the effectiveness of therapeutic interventions. The methodology presented here aims to provide a general guideline for investigators.

Behavioral testing is the gold standard for determining outcomes following brain injury, and can identify the presence of developmental disabilities in infants and children. Neurodevelopmental reflexes are an early indicator of these abnormalities. A host of easily accomplished developmental reflex tests in the neonatal rodent were developed and described here.

Neurodevelopmental reflex testing is commonly used in clinical practice to assess the maturation of the nervous system. Neurodevelopmental reflexes are ...

Noninvasive, High-throughput Determination of Sleep Duration in Rodents

Traditionally, sleep is monitored by an electroencephalogram (EEG). EEG studies in rodents require surgical implantation of the electrodes followed by a long recovery period. To perform an EEG recording, the animal is connected to a receiver, creating an unnatural tether to the head-mount. EEG monitoring is time consuming, carries risk to the animal, and is not a completely natural setting for the measurement of sleep. Alternative methods to detect sleep, particularly in a high-throughput fashion, would greatly advance the field of sleep research. Here, we describe a validated method for detecting sleep via activity-based home-cage monitoring. Previous studies have shown that sleep assessed via this method has a high degree of agreement with sleep defined by traditional EEG-based measures. Whereas this method is validated for total sleep time, it is important to note that sleep bout duration should be assessed by an EEG which has better temporal resolution. The EEG can also differentiate rapid eye movement (REM) and non-REM sleep, giving more detail about the exact nature of sleep. Nevertheless, activity-based sleep determination can be used to analyze multiple days of undisturbed sleep and to assess sleep as a response to an acute event (like stress). Here, we show the power of this system to detect the response of mice to daily intraperitoneal injections.

We describe a high-throughput method of measuring sleep by means of activity-based home-cage monitoring. This method offers advantages over traditional EEG-based methods. It is well validated for the determination of total sleep duration and can be a powerful tool to monitor sleep in rodent models of human disease.

Traditionally, sleep is monitored by an electroencephalogram (EEG). EEG studies in rodents require surgical implantation of the electrodes followed by a ...

Measuring Active and Passive Tameness Separately in Mice

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two behavioral components: a reluctance to avoid humans (passive tameness) and a motivation to approach humans (active tameness). To quantify these components in mice, we previously developed behavioral tests for active tameness, passive tameness, and the willingness to stay on a human hand, each designed to be completed within 3 min. The data obtained were used for selective breeding, with a large number of mice analyzed per generation. The active tameness test measures the movement of the mouse toward a human hand and the contact it engages in. The passive tameness test measures the duration of time that a mouse tolerates human touch. In the stay-on-hand test, a mouse is placed on a human hand and touched slowly using the thumb of that hand; the duration of time that the animal remains on the hand is measured. Here, we describe the test set-up and apparatus, explain the procedures, and discuss the appropriate data analysis. Finally, we explain how to interpret the results.

Tameness in animals includes a reduction of avoidance responses to humans (passive tameness) and an increase in active approaches to humans (active tameness). Here, we describe detailed protocols for three behavioral tests (active tameness, passive tameness, and stay-on-hand tests) to separately measure the active and passive tameness of mice.

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two ...

Novel Object Recognition and Object Location Behavioral Testing in Mice on a Budget

Ethologically relevant behavioral testing is a critical component of any study that uses mouse models to study the cognitive effects of various physiological or pathological changes. The object location task (OLT) and the novel object recognition task (NORT) are two effective behavioral tasks commonly used to reveal the function and relative health of specific brain regions involved in memory. While both of these tests exploit the inherent preference of mice for the novelty to reveal memory for previously encountered objects, the OLT primarily evaluates spatial learning, which relies heavily on hippocampal activity. The NORT, in contrast, evaluates non-spatial learning of object identity, which relies on multiple brain regions. Both tasks require an open-field-testing arena, objects with equivalent intrinsic value to mice, appropriate environmental cues, and video recording equipment and the software. Commercially available systems, while convenient, can be costly. This manuscript details a simple, cost-effective method for building the arenas and setting up the equipment necessary to perform the OLT and NORT. Furthermore, the manuscript describes an efficient testing protocol that incorporates both OLT and NORT and provides typical methods for data acquisition and analysis, as well as representative results. Successful completion of these tests can provide valuable insight into the memory function of various mouse model systems and appraise the underlying neural regions that support these functions.

Here we provide a protocol which includes comprehensive instructions for the economical establishment of murine object location and novel object recognition behavioral testing, including the design, cost, and construction of required equipment as well as execution of behavioral testing, data collection, and analysis.

Ethologically relevant behavioral testing is a critical component of any study that uses mouse models to study the cognitive effects of various ...

Automated Measurements of Sleep and Locomotor Activity in Mexican Cavefish

Across phyla, sleep is characterized by highly conserved behavioral characteristics that include elevated arousal threshold, rebound following sleep deprivation, and consolidated periods of behavioral immobility. The Mexican cavefish, Astyanax mexicanus (A. mexicanus), is a model for studying trait evolution in response to environmental perturbation. A. mexicanus exist as in eyed surface-dwelling forms and multiple blind cave-dwelling populations that have robust morphological and behavioral differences. Sleep loss has occurred in multiple, independently-evolved cavefish populations. This protocol describes a methodology for quantifying sleep and locomotor activity in A. mexicanus cave and surface fish. A cost-effective video monitoring system allows for behavioral imaging of individually-housed larval or adult fish for periods of a week or longer. The system can be applied to fish aged 4 days post fertilization through adulthood. The approach can also be adapted for measuring the effects of social interactions on sleep by recording multiple fish in a single arena. Following behavioral recordings, data is analyzed using automated tracking software and sleep analysis is processed using customized scripts that quantify multiple sleep variables including duration, bout length, and bout number. This system can be applied to measure sleep, circadian behavior, and locomotor activity in almost any fish species including zebrafish and sticklebacks.

This protocol details the methodology for quantifying locomotor behavior and sleep in the Mexican cavefish. Previous analyses are extended to measure these behaviors in socially-housed fish. This system can be widely applied to study sleep and activity in other fish species.

Across phyla, sleep is characterized by highly conserved behavioral characteristics that include elevated arousal threshold, rebound following sleep ...

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Sleep loss and circadian misalignment contribute to a meaningful proportion of operational accidents and incidents. Countermeasures and work scheduling designs aimed at mitigating fatigue are typically evaluated in controlled laboratory environments, but the effectiveness of translating such strategies to operational environments can be challenging to assess. This manuscript summarizes an approach for collecting sleep, circadian, fatigue, and performance data in a complex operational environment. We studied 44 airline pilots over 34 days while they flew a fixed schedule, which included a baseline data collection with 5 days of mid-morning flights, four early flights, four high-workload mid-day flights, and four late flights that landed after midnight. Each work block was separated by 3&#8211;4 days of rest. To assess sleep, participants wore a wrist-worn research-validated activity monitor continuously and completed daily sleep diaries. To assess the circadian phase, pilots were asked to collect all urine produced in four or eight hourly bins during the 24 h after each duty block for the assessment of 6-sulfatoxymelatonin (aMT6s), which is a biomarker of the circadian rhythm. To assess subjective fatigue and objective performance, participants were provided with a touch-screen device used to complete the Samn-Perelli Fatigue Scale and Psychomotor Vigilance Task (PVT) during and after each flight, and at waketime, mid-day, and bedtime. Using these methods, it was found that sleep duration was reduced during early starts and late finishes relative to baseline. Circadian phase shifted according to duty schedule, but there was a wide range in the aMT6s peak between individuals on each schedule. PVT performance was worse on the early, high-workload, and late schedules relative to baseline. Overall, the combination of these methods was practical and effective for assessing the influence of sleep loss and circadian phase on fatigue and performance in a complex operational environment.

Sleep loss and circadian misalignment contribute to numerous operational accidents and incidents. The effectiveness of countermeasures and work scheduling designs aimed at mitigating fatigue can be challenging to evaluate in operational environments. This manuscript summarizes an approach for collecting sleep, circadian, fatigue, and performance data in complex operational environments.

Sleep loss and circadian misalignment contribute to a meaningful proportion of operational accidents and incidents. Countermeasures and work scheduling ...