This research was supported by grant funding from Virginia&#8217;s Commonwealth Health Research Board.

The protocol for the ease of explanation has been divided into 2 parts: 1) Experimental procedure and 2) Automated analysis. All animals were treated according to the Guide for the Care and Use of Laboratory Animals15, and all procedures were approved by the Institutional Animal Care and Use Committee.
1. Experimental Procedure
<ol>
	<li>Set up the cage, which is a black non-reflective Plexiglas rectangular box (52 x 25 x 23 cm3) divided into three compartments: social, nonsocial, and a neutral middle compartment (Figure 1). Place inverted wire cups in each of the end compartments during sessions I and II (discussed below) and house the stimulus mouse during session II.</li>
	<li>Set up the camera in such a manner that the cage fills the field of view. Since lighting can interfere with mouse behavior, maintain a luminance of no more than 3.5 lux inside the cage, coming from indirect light from an incandescent light bulb and measured on the cage floor in upward direction. Also use an infrared light source, which mice cannot sense but the camera can detect. Record all movies in 720 x 480 standard definition.</li>
	<li>Record a single frame of an empty cage for later image processing (called the &#8220;reference frame&#8221;) and save as a grayscale image.</li>
	<li>Session I: Introduce test mouse into the cage and wave hand over the cage, indicating the start of session (compare Automated Analysis). Record movie for 10 min. At the end of 10 min, put the mouse back into its original cage.</li>
	<li>Session II: Put the stimulus mouse under one of the inverted cups (counterbalanced).</li>
	<li>Use the &#8220;Social left&#8221; or &#8220;Social right&#8221; button to select whether the stimulus mouse is in the inverted cup on the left or in the inverted cup on the right. 
	NOTE: The inverted cup with the stimulus mouse is called the &#8220;social cup&#8221;, whereas the other cup the &#8220;nonsocial cup&#8221;. The compartment in which the social cup is located is called the social compartment, the compartment with the nonsocial cup is the nonsocial compartment, and the middle compartment is the &#8220;neutral compartment&#8221;.</li>
	<li>Introduce the test mouse into the cage. Wave hand over the cage to indicate the start of the session. Record movie for 10 min. Importantly, keep mice in the sociability apparatus before removing the inverted cups to begin Session III.</li>
	<li>Session III: Remove the inverted cups, release both mice and allow the test and stimulus mice to interact freely with each other. Wave hand over the cage to indicate the start of the session. Record movie for 10 min. At the end of 10 min, put both mice back into their respective cages.</li>
</ol>
2. Automated Analysis
NOTE: The commands in section 2 are issued via a graphical user interface (see Figure 2) that controls our software. Here we explain the step-by-step processing that our software allows; the software is also capable of performing the analysis in batch mode without user input.
<ol>
	<li>For every movie, execute the following processing steps:
	<ol>
		<li>Load movie (click Load button).</li>
		<li>Select cage configuration, which tells the analysis program the location of cage boundaries, compartment boundaries, and cup locations. Select one of four saved configurations or manually adjust all coordinates. 
		NOTE: The configuration usually does not change from one experiment to the next and can therefore be reused.</li>
		<li>For each frame of the movie, perform the following processing steps (2.1.3.1-2.1.3.6).
		<ol>
			<li>Convert the frame to grayscale by clicking the &#8220;Grayscale&#8221; button.</li>
			<li>Digitally subtract the grayscale reference frame (see step 1.3) by clicking the &#8220;Subtract&#8221; button. NOTE: The goal of this step is to make the pixel values of the frame very close to zero everywhere except for the mouse position.</li>
			<li>Binarize the frame by setting all pixels below a certain threshold level to black, all pixels above that level to white (click the &#8220;Binarize&#8221; button). 
			Note: The idea is that since the mouse pixels generally have higher values than the remaining pixels, the mouse pixels will become white and all other pixels black. The optimal threshold level depends on the lighting condition and can be determined by assessing the mouse shape throughout a movie. If the threshold is chosen too low, the mouse appears too large, and pixels that do not belong to the mouse can be colored white. If the threshold is too high, the mouse becomes small and can disintegrate into disconnected pieces. In the recorded movies, the optimal threshold was always between 20 and 35 (on a scale from 0 to 255).</li>
			<li>Erode13 the binarized picture e times, then dilate13 2e times, then erode again e times, by pushing the button &#8220;Erod/Dil&#8221;. 
			Note: The purpose to this procedure is to remove the tail. For the resolution (720 x 480) that was used, e = 3 worked in all circumstances. 
			Note: The software checks automatically for the presence of a hand in the picture (during the recording of movies, hands are waved through the picture to indicate the beginning of a session). If a hand is present, there will be unusually many white pixels in the binarized frame because the hand is much larger than a mouse. The condition for the presence of a hand is that there are more than 10,000 white pixels in the binarized frame. The software determines the beginnings of sessions I, II, and III, by detecting the range of frames in which hand movements occur.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>In sessions I and II, continue as follows:
	<ol>
		<li>Detect the largest connected component of the set of white pixels (Click &#8220;LComp&#8221;). Note: The purpose of this step is to eliminate white pixels that do not belong to the mouse, e.g., caused by the motion of the stimulus mouse in session II. The largest connected component is in almost all frames the mouse.</li>
		<li>Determine the two most distant white pixels (called the &#8220;ends&#8221; of the mouse) by clicking &#8220;Find Ends&#8221;. 
		Note: The software establishes the continuity of the two ends, i.e., for each of the ends in the first frame to which of the ends in the subsequent frames they belong. The general idea is that since frames are recorded at high rate, the ends cannot travel far from one frame to the next, so that for the correct continuation of the ends from one frame to the next is that which minimizes the sum of the distances that the ends move. See the Discussion for more detail.</li>
		<li>Determine which end of the mouse is the nose.
		<ol>
			<li>Determine the direction in which a mouse moves by observing how the center of gravity (COG) changes from frame to frame (the COG&#8217;s motion is the motion of the sum of all mouse pixels). 
			Note: The COG of a set of pixels p1, ... , pn&#160; with coordinates x1, .. , xn &#160; is defined by: 
			<img alt="Equation 1" src="/files/ftp_upload/52508/52508eq1.jpg" /> 
			Mice usually move forward (i.e., towards their nose). In a section of several hundred frames, there is always very high confidence in the head/tail detection. 
			Note: The software automatically determines towards which of the detected ends the mouse is moving; this end is identified as the nose and marked with a red circle in the movie. When the detected nose is marked with a red circle in every frame, the user can check the quality of the detection.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>In session III, continue as follows:
	<ol>
		<li>Detect two largest components of white pixels.
		<ol>
			<li>If both are of acceptable size for a mouse and their centers of gravity (COGs) are compatible with the mouse COGs of the previous frame, consider these two components the two mice.</li>
			<li>Consider mouse sizes acceptable if they have not changed by more than 20% since the previous frame, and consider COGs of two consecutive frames as compatible if their difference is not larger than the distance a mouse can travel in the time between frames (this distance follows from the maximum mouse speed, which can be determined as part of the preparations of an experiment series by analyzing the motion of several individual mice (as in sessions I and II). 
			Note: If the two largest components are not acceptable sizes for a mouse, or the COGs are too different from those in the previous frame, the software automatically increases the binarization threshold until the two largest components are of acceptable size and their COGs are compatible with those of the previous frame.</li>
		</ol>
		</li>
		<li>Click the test mouse in the first frame. Use the analysis in 2.3.1 to identify both test and stimulus mouse in every frame of session III.</li>
		<li>Identify the frames in session III in which the one mouse socially approaches the other. Note: The software implements this step by automatically checking that the distance between the mice is less than the typical interaction distance of mice (we use 2 cm).</li>
		<li>When the software plays a short segment of the movie with the detected approach to the user, click a button to indicate whether this approach qualifies as a social approach by the test mouse, social avoidance by the test mouse, or neither. 
		Note: Step 2.3.4 can be automatized if it is known which mouse is the test mouse. Since this information gets lost when the mice get too close to each other (or climb on top of each other), and since we have not yet found a way to label the mice in a way that can be detected reliably by our software AND does not affect their behavior, we have reverted to manual classification for now.</li>
	</ol>
	</li>
	<li>To evaluate processed movies, load movie using Load button.
	<ol>
		<li>Click on Start Session 1 to display the first frame of session 1 (or Start Session 2 to display the first frame of session 2).</li>
		<li>Click on Play/Stop to play and stop movies. 
		Note: The processed movies will display mouse with head and tail marked with differently colored circles. All sociability measures are displayed on the screen and updated as the movie plays.</li>
		<li>Export sociability data in Excel format by clicking &#8220;Export&#8221;.</li>
		<li>Click on &#8220;Compile Data&#8221; to compile all the data of all movies in a folder into a single excel file.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Brodkin, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BALB/c+mice:+Low+sociability+and+other+phenotypes+that+may+be+relevant+to+autism.">BALB/c mice: Low sociability and other phenotypes that may be relevant to autism.</a> Behavioural Brain Research. 176, 53-65 (2007).</li><li>Deutsch, S. I., Burket, J. A., Urbano, M. R., Herndon, A. L., Winebarger, E. E., Mohammadi, M. 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I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapamycin+improves+sociability+in+the+BTBR+T(+)Itpr3(tf)/J+mouse+model+of+autism+spectrum+disorders.">Rapamycin improves sociability in the BTBR T(+)Itpr3(tf)/J mouse model of autism spectrum disorders.</a> Brain Research Bulletin. 100, 70-75 (2014).</li><li>Burket, J. A., Benson, A. D., Tang, A. H., Deutsch, S. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=D-Cycloserine+improves+sociability+in+the+BTBR+T++Itpr3tf/J+mouse+model+of+autism+spectrum+disorders+with+altered+Ras/Raf/ERK1/2+signaling.">D-Cycloserine improves sociability in the BTBR T+ Itpr3tf/J mouse model of autism spectrum disorders with altered Ras/Raf/ERK1/2 signaling.</a> Brain Research Bulletin. 96, 62-70 (2013).</li><li>Burket, J. A., Herndon, A. L., Deutsch, S. 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I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetically+inbred+BALB/c+mice+differ+from+outbred+Swiss+Webster+mice+on+discrete+measures+of+sociability:+relevance+to+a+genetic+mouse+model+of+autism+spectrum+disorders.">Genetically inbred BALB/c mice differ from outbred Swiss Webster mice on discrete measures of sociability: relevance to a genetic mouse model of autism spectrum disorders.</a> Autism Research. 4, 393-400 (2011).</li><li>Jacome, L. F., Burket, J. A., Herndon, A. L., Cannon, W. R., Deutsch, S. 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The authors have nothing to disclose.

By combining videotaping mice and automatic movie analysis, we have created an affordable, reliable high-throughput screening technique.
The accuracy of the automated analysis was compared with the results of manual analysis for more than 100 movies. In the overwhelming majority of frames (&#62; 99%) of frames, the nose of the mouse is identified with good precision. Most of the (few) misdetections have no effect on the sociability measures, so that around 80% of the movies do not require any ...

Impaired sociability is one of the primary symptom domains in a range of neurodevelopmental disorders, including autism spectrum disorders (ASDs)1,2. It severely limits the patients&#39; ability to develop relationships and greatly affects patients, families, and caregivers2,3.
In an effort to better understand the mechanism underlying impaired sociability and develop treatments, several mouse models have been studied1,4&#8211;9. One such strain is the BALB/c mouse, an inbred strain that exhibits strikingly low sociability, resembling features seen in patients with ASD58&#8211;12. For example, the BALB/c mouse displays a lower frequency of social approaches and a usually negative response to social approaches by a stimulus mouse (e.g., social avoidance) than the Swiss Webster comparator strain10.
To test whether a proposed treatment is effective in increasing sociability, objective measures are needed. A widely accepted framework is to analyze the sociability in a standardized apparatus that has three compartments (see Figure 1).
The left and right compartments each contain an inverted wire cup which houses a socially salient stimulus mouse. The test mouse is released into the apparatus for three intervals of 10 min (sessions I-III); session I assesses the locomotor activity of the test mouse, while sessions II and III assess different aspects of the test mouse&#39;s sociability.
In session I, the test mouse is allowed to acclimate to the apparatus. In this session, the number of transitions that the test mouse makes between the different compartments is measured. Importantly, sociability measures obtained in the standard three-compartment apparatus are dependent upon locomotor activity, and reduced locomotor activity can confound interpretation of sociability data.
In session II, the test mouse is moving freely and a stimulus mouse is placed under one of the inverted cups (counterbalanced). The stimulus mice are 4-week old outbred male ICR mice, age- and sex-matched to the test mice. The stimulus mouse is enclosed in an inverted cup in the side designated as the social compartment, and an empty inverted cup is placed in the side designated as the nonsocial compartment. In session II, the sociability of the test mouse is quantified by comparing the time it spends near the &#8220;social&#8221; inverted cup (less than 2 cm away) vs. the time it spends near the &#8220;nonsocial&#8221; inverted cup, and by the time it spends in the social compartment vs. the time it spends in the nonsocial compartment. Swiss Webster comparator mice spend significantly more time in the social compartment and near the social inverted cup compared to BALB/c mice that show no significant preference for the social inverted cup or the social compartment12.
In session III, test and stimulus mice are allowed to interact freely (inverted cups are removed). Measures of sociability, stereotypic behaviors and transitions between compartments are reliably obtained in the third 10 min session of free interaction between test and stimulus mice and analyzed. In this report, the sociability of the test mouse is quantified via two measures: 1) the number of social approaches it makes toward the stimulus mouse, where a social approach is defined as moving forward (nose first) towards the stimulus mouse so that the nose is less than 2 cm away from the stimulus mouse; 2) the number of avoidances of social approaches by the stimulus mouse. The test mouse is considered to be avoiding the approach if it turns or moves away from the stimulus mouse, or if it temporarily stops moving (&#8220;freezing behavior&#8221;) after the stimulus mouse has approached the test mouse. BALB/c mice show a decrease in number of social approaches made towards the stimulus mouse and an increase in the number of negative responses to social approaches by the stimulus mouse, compared to the Swiss Webster comparator strain10.
The evaluation of the behavioral movies has traditionally been done manually, i.e., by watching the movie carefully (possibly at reduced speed) and activating stopwatches for the time the mouse spends in a certain compartment or near one of the inverted cups10. This method requires watching of the movie repeatedly and is, therefore, very time-consuming. Also, the accuracy is limited by the rater&#8217;s reaction time for the stopwatch measurements and ability to perceive whether the mouse is within 2 cm of the inverted cup. In recent work, two compounds, (D-serine and D-cycloserine) have proven effective in restoring sociability in BALB/c mice9,10,12. It is known that both components modulate the NMDA receptor, which is known to play a central role in social behavior2,12. A large array of compounds is known to modulate NMDA receptor activity in a variety of well-defined ways, and the potential for a breakthrough in ASD treatment makes the expedited evaluation of these compounds a priority and a fast automatic method for evaluation highly desirable.
Described below is an automatic analysis procedure developed for the assessment of mouse sociability. It uses image processing methods on all the frames of the mouse movies to identify the position of the mouse or mice. In sessions I and II, it further detects nose position and uses it to compute sociability measures. In session III, it automatically detects all approaches, but manual classification (social approach, social avoidance, or other) is required.

<table>
	<tbody>
		<tr>
			<td>Plexiglas cage</td>
			<td>Norva Plastics, Norfolk, VA</td>
			<td>custom made</td>
			<td>Dimensions and layout described in manuscript, 
			can be adjusted according to needs. 
			Use non-reflective plexiglas for to facilitate image processing</td>
		</tr>
		<tr>
			<td>Wire cups</td>
			<td>Kitchen plus</td>
			<td>315</td>
			<td>Use one to house stimulus mouse, one empty</td>
		</tr>
		<tr>
			<td>Video camera</td>
			<td>SONY</td>
			<td>HDR-PJ790</td>
			<td>Can be replaced by any camera with 
			Comparable specifications</td>
		</tr>
		<tr>
			<td>OpenCV (Image processing library)</td>
			<td>Willow Garage</td>
			<td>N/A</td>
			<td>Any modern image processing library 
			can be used.</td>
		</tr>
	</tbody>
</table>

experimental assessment of mouse sociability using an automated image processing approach

Mouse is the preferred model organism for testing drugs designed to increase sociability. We present a method to quantify mouse sociability in which the test mouse is placed in a standardized apparatus and relevant behaviors are assessed in three different sessions (called session I, II, and III).
The apparatus has three compartments (see Figure 1), the left and right compartments contain an inverted cup which can house a mouse (called &#34;stimulus mouse&#34;).
In session I, the test mouse is placed in the cage and its mobility is characterized by the number of transitions made between compartments. In session II, a stimulus mouse is placed under one of the inverted cups and the sociability of the test mouse is quantified by the amounts of time it spends near the cup containing the enclosed stimulus mouse vs. the empty inverted cup. In session III, the inverted cups are removed and both mice interact freely. The sociability of the test mouse in session III is quantified by the number of social approaches it makes toward the stimulus mouse and by the number of times it avoids a social approach by the stimulus mouse.
The automated evaluation of the movie detects the nose of the test mouse, which allows the determination of all described sociability measures in session I and II (in session III, approaches are identified automatically but classified manually). To find the nose, the image of an empty cage is digitally subtracted from each frame of the movie and the resulting image is binarized to identify the mouse pixels. The mouse tail is automatically removed and the two most distant points of the remaining mouse are determined; these are close to nose and base of tail. By analyzing the motion of the mouse and using continuity arguments, the nose is identified.
<img alt="Figure 1" src="/files/ftp_upload/52508/52508fig1.jpg" /> 
Figure 1. Assessment of Sociability During 3 sessions. Session I (top): Acclimation of test mouse to the cage. Session II (middle): Test mouse moving freely in the cage while the stimulus mouse is enclosed in an inverted cup. Session III (bottom): Both test mouse and stimulus mouse are allowed to move freely and interact with each other.

Figure 3 shows a color frame of a behavioral movie with an empty cage. The mouse has not been introduced into the cage yet. The position of the cups, (social and nonsocial) and the compartment boundaries are superimposed. The color frame of empty cage is converted to 8 bit grayscale as shown in Figure 4 and used as a reference frame. The reference frame is subtracted from every other frame of the captured movie.
Figure 5 shows one of the frame...

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Experimental Assessment of Mouse Sociability Using an Automated Image Processing Approach

This protocol describes a method to quantify mouse sociability. Mice are videotaped as they move and interact in a special cage. Movie processing allows for the automated quantification of sociability with excellent accuracy and reliability.

Mouse is the preferred model organism for testing drugs designed to increase sociability. We present a method to quantify mouse sociability in which the ...

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8.3K Views.  Old Dominion University. This protocol describes a method to quantify mouse sociability. Mice are videotaped as they move and interact in a special cage. Movie processing allows for the automated quantification of sociability with excellent accuracy and reliability.

Video: Experimental Assessment of Mouse Sociability Using an Automated Image Processing Approach

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Objective and easy measurement of sensory processing is extremely difficult in nonverbal or vulnerable pediatric patients. We developed a new methodology to quantitatively assess infants and children&#39;s cortical processing of light touch, speech sounds, and the multisensory processing of the 2 stimuli, without requiring active subject participation or causing discomfort in vulnerable patients.

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Motor control and balance performance are known to deteriorate with age. This paper presents a number of standard noninvasive behavioral tests with the addition of a simple rotary stimulus to challenge the vestibular system and show changes in balance performance in a murine model of aging.

Age related decline in balance performance is associated with deteriorating muscle strength, motor coordination and vestibular function. While a number of ...

Assessment of Social Cognition in Non-human Primates Using a Network of Computerized Automated Learning Device (ALDM) Test Systems

Fagot &#38; Paleressompoulle1 and Fagot &#38; Bonte2 have published an automated learning device (ALDM) for the study of cognitive abilities of monkeys maintained in semi-free ranging conditions. Data accumulated during the last five years have consistently demonstrated the efficiency of this protocol to investigate individual/physical cognition in monkeys, and have further shown that this procedure reduces stress level during animal testing3. This paper demonstrates that networks of ALDM can also be used to investigate different facets of social cognition and in-group expressed behaviors in monkeys, and describes three illustrative protocols developed for that purpose. The first study demonstrates how ethological assessments of social behavior and computerized assessments of cognitive performance could be integrated to investigate the effects of socially exhibited moods on the cognitive performance of individuals. The second study shows that batteries of ALDM running in parallel can provide unique information on the influence of the presence of others on task performance. Finally, the last study shows that networks of ALDM test units can also be used to study issues related to social transmission and cultural evolution. Combined together, these three studies demonstrate clearly that ALDM testing is a highly promising experimental tool for bridging the gap in the animal literature between research on individual cognition and research on social cognition.

Assessment of Social Cognition in Non-human Primates Using a Network of Computerized Automated Learning Device ALDM Test Systems

Fagot &#38; Paleressompoulle1 have published an automated learning device (ALDM) aimed at testing individual cognitive abilities in semi-free ranging monkeys. The main goal of our protocol is to use a network of ALDM test units to study social cognition in non-human primates.

Fagot &#38; Paleressompoulle1 and Fagot &#38; Bonte2 have published an automated learning device (ALDM) for the study of cognitive abilities of monkeys ...

An Objective and Child-friendly Assessment of Arm Function by Using a 3-D Sensor

Progressive and irreversible muscle atrophy characterizes Spinal Muscular Atrophy (SMA) and other similar muscle disorder diseases. Objective assessment of muscle functions is an essential and important, although challenging, prerequisite for successful clinical trials. Current clinical rating scales restrain the movement abnormalities to certain predefined coarse-grained individual items. The Kinect 3-D sensor has emerged as a low-cost and portable motion sensing technology used to capture and track people&#39;s movement in many medical and research fields. A novel approach using this 3-D sensor was developed and a game-like test was designed to objectively measure the upper limb function of patients with SMA. The prototype test targeted joint movement capability. While sitting in a virtual scene, the patient was instructed to extend, flex, and lift the whole arm in order to reach and place some objects. Both kinematic and spatiotemporal characteristics of upper limb movement were extracted and analyzed, e.g., elbow extension and flexion angles, hand velocity, and acceleration. The first study included a small cohort of 18 ambulant SMA patients and 19 age- and gender-matched healthy controls. A comprehensive analysis of arm movement was achieved; however, no significant difference between the groups were found due to the mismatch of patient&#39;s capability and the test difficulty. Based on this experience, a second version of the test consisting of a modified version of the first game with increased difficulties and a second game targeting muscle endurance were designed and implemented. The new test has not been conducted in any patient groups yet. Our work has demonstrated the potential capability of the 3-D sensor in assessing such muscle function and suggested an objective approach to complement the clinical rating scales.

An objective measure of muscle functions is challenging especially in children. Based on a commercially available digital 3-D sensor, a child-friendly gaming test was developed to assess upper limb function for clinical trials.

Progressive and irreversible muscle atrophy characterizes Spinal Muscular Atrophy (SMA) and other similar muscle disorder diseases. Objective assessment ...

Systematic Assessment of Well-Being in Mice for Procedures Using General Anesthesia

In keeping with the 3R Principle (Replacement, Reduction, Refinement) developed by Russel and Burch, scientific research should use alternatives to animal experimentation whenever possible. When there is no alternative to animal experimentation, the total number of laboratory animals used should be the minimum needed to obtain valuable data. Moreover, appropriate refinement measures should be applied to minimize pain, suffering, and distress accompanying the experimental procedure. The categories used to classify the degree of pain, suffering, and distress are non-recovery, mild, moderate, or severe (EU Directive 2010/63). To determine which categories apply in individual cases, it is crucial to use scientifically sound tools.
The well-being-assessment protocol presented here is designed for procedures during which general anesthesia is used. The protocol focuses on home cage activity, the Mouse Grimace Scale, and luxury behaviors such as burrowing and nest building behavior as indicators of well-being. It also uses the free exploratory paradigm for trait anxiety-related behavior. Fecal corticosterone metabolites as indicators of acute stress are measured over the 24-h post-anesthetic period.
The protocol provides scientifically solid information on the well-being of mice following general anesthesia. Due to its simplicity, the protocol can easily be adapted and integrated in a planned study. Although it does not provide a scale to classify distress in categories according to the EU Directive 2010/63, it can help researchers estimate the degree of severity of a procedure using scientifically sound data. It provides a way to improve the assessment of well-being in a scientific, animal-centered manner.

We developed a protocol to assess well-being in mice during procedures using general anesthesia. A series of behavioral parameters indicating levels of well-being as well as glucocorticoid metabolites were analyzed. The protocol can serve as a general aid to estimate the degree of severity in a scientific, animal-centered manner.

In keeping with the 3R Principle (Replacement, Reduction, Refinement) developed by Russel and Burch, scientific research should use alternatives to animal ...

An Electrophysiology Protocol to Measure Reward Anticipation and Processing in Children

We present a protocol designed to measure the neural correlates of reward in children. The protocol allows researchers to measure both reward anticipation and processing. Its purpose is to create a reward task that is appropriate for young children with and without autism while controlling reward properties between two conditions: social and nonsocial. The current protocol allows for comparisons of brain activity between social and nonsocial reward conditions while keeping the reward itself identical between conditions. Using this protocol, we found evidence that neurotypical children demonstrate enhanced anticipatory brain activity during the social condition. Furthermore, we found that neurotypical children anticipate social reward more robustly than children with autism diagnoses. As the task uses snacks as a reward, it is most appropriate for young children. However, the protocol may be adapted for use with adolescent or adult populations if snacks are replaced by monetary incentives. The protocol is designed to measure electrophysiological events (event-related potentials), but it may be customized for use with eye-tracking or fMRI.

This protocol is designed to measure reward anticipation and processing in young children with and without autism. Specifically, the protocol is designed to study the neural correlates of reward during social and nonsocial conditions while controlling for reward between conditions.

We present a protocol designed to measure the neural correlates of reward in children. The protocol allows researchers to measure both reward anticipation ...

An Experimental Paradigm for Measuring the Effects of Ageing on Sentence Processing

Previous studies have found that older adults have greater difficulties in processing syntactically complex sentences than younger adults. However, the exact regions where the difficulties arise have not been fully identified. In this study, a maze task was implemented to investigate how older adults and younger adults differentially processed two types of sentences with different levels of syntactic complexity, namely subject relative clauses and object relative clauses. Participants were asked to choose between two alternatives at each segment of the sentences. The task required participants to engage in a strictly incremental mode of processing. The reading times for each segment were recorded, allowing the quantification of the difficulty of sentence reading. The task allowed us to identify the exact locations of the processing difficulty and thus facilitate a more accurate assessment of the age-related decline in sentence processing. The results indicate that the effect of ageing was found mainly at the head nouns, but not at other regions of the sentences, a finding which suggests that the maze task is an effective method to identify the exact location of the ageing effect on sentence processing. The implications of this experimental paradigm for investigating the effect of ageing on sentence processing are discussed.

Here, we present a protocol to examine the age-related decline in sentence processing using a maze task that allowed us to localize the processing difficulty at each word of the sentences during reading.

Previous studies have found that older adults have greater difficulties in processing syntactically complex sentences than younger adults. However, the ...

Assessment of Stress Effects on Cognitive Flexibility using an Operant Strategy Shifting Paradigm

Stress affects cognitive function. Whether stress enhances or impairs cognitive function depends on several factors, including the 1) type, intensity, and duration of the stressor; 2) type of cognitive function under study; and 3) timing of the stressor in relation to learning or executing the cognitive task. Furthermore, sex differences among the effects of stress on cognitive function have been widely documented. Described here is an adaptation of an automated operant strategy shifting paradigm to assess how variations in stress affect cognitive flexibility in male and female Sprague Dawley rats. Specifically, restraint stress is used before or after training in this operant-based task to examine how stress affects cognitive performance in both sexes. Particular brain areas associated with each task in this automated paradigm have been well-established (i.e., the medial prefrontal cortex and orbitofrontal cortex). This allows for targeted manipulations during the experiment or the assessment of particular genes and proteins in these regions upon completion of the paradigm. This paradigm also allows for the detection of different types of performance errors that occur after stress, each of which has defined neural substrates. Also identified are distinct sex differences in perseverative errors after a repeated restraint stress paradigm. The use of these techniques in a preclinical model may reveal how stress affects the brain and impairs cognition in psychiatric disorders, such as post-traumatic stress disorder (PTSD) and major depressive disorder (MDD), which display marked sex differences in prevalence.

Stressful life events impair cognitive function, increasing the risk of psychiatric disorders. This protocol illustrates how stress affects cognitive flexibility using an automated operant strategy shifting paradigm in male and female Sprague Dawley rats. Specific brain areas underlying particular behaviors are discussed, and translational relevance of results are explored.

Stress affects cognitive function. Whether stress enhances or impairs cognitive function depends on several factors, including the 1) type, intensity, and ...

Concept Development and Use of an Automated Food Intake and Eating Behavior Assessment Method

The vast majority of dietary and eating behavior assessment methods are based on self-reports. They are burdensome and also prone to measurement errors. Recent technological innovations allow for the development of more accurate and precise dietary and eating behavior assessment tools that require less effort for both the user and the researcher. Therefore, a new sensor-based device to assess food intake and eating behavior was developed. The device is a regular dining tray equipped with a video camera and three separate built-in weighing stations. The weighing stations measure the weight of the bowl, plate, and drinking cup continuously over the course of a meal. The video camera positioned to the face records eating behavior characteristics (chews, bites), which are analyzed using artificial intelligence (AI)-based automatic facial expression software. The tray weight and the video data are transported at real-time to a personal computer (PC) using a wireless receiver. The outcomes of interest, such as the amount eaten, eating rate and bite size, can be calculated by subtracting the data of these measures at the timepoints of interest. The information obtained by the current version of the tray can be used for research purposes, an upgraded version of the device would also facilitate the provision of more personalized advice on dietary intake and eating behavior. Contrary to the conventional dietary assessment methods, this dietary assessment device measures food intake directly within a meal and is not dependent on memory or the portion size estimation. Ultimately, this device is therefore suited for daily main meal food intake and eating behavior measures. In the future, this technology based dietary assessment method can be linked to health applications or smart watches to obtain a complete overview of exercise, energy intake, and eating behavior.

This protocol shows and explains a new technology-based dietary assessment method. The method consists of a dining tray with multiple built-in weighing scales and a video camera. The device is unique in the sense that it incorporates automated measures of food and drink intake and eating behavior over the course of a meal.

The vast majority of dietary and eating behavior assessment methods are based on self-reports. They are burdensome and also prone to measurement errors. ...