The authors wish to thank all members of the Orofacial Physiology and Perceptual Analysis Lab (OPPAL; Etter, Director) and the Sensory Evaluation Center (Hayes, Director), both located at Penn State.

All procedures were approved by the Institutional Review Board for conducting human research at The Pennsylvania State University and were consistent with the Declaration of Helsinki.
1. Set-up
<ol>
	<li>Display all monofilaments with target points between 0.008g (lowest factory setting) and 15 g (a priori ceiling determined during pilot testing).
	<ol>
		<li>Set out the monofilaments with target forces of 0.008, 0.02, 0.04, 0.07, 0.16, 0.4, 0.6, 1.0, 1.4, 2.0, 4.0, 6.0, 8.0, 10.0, and 15.0 g.</li>
	</ol>
	</li>
	<li>Set the monofilaments out on the table so each target level can be easily read by the experimenter.</li>
	<li>Seat the participant in a comfortable chair with a glass of water within arm&#39;s reach.</li>
	<li>Instruct the participant that when it is time, they will be asked to close their eyes and stick out their tongue.
	<ol>
		<li>Identify the approximate testing location at midline tongue. The testing location should be approximately 10 mm posterior to the tongue tip.</li>
		<li>Encourage the participant to stop regularly and take a sip of water approximately every 5-10 trials or after the first incorrect response for either testing protocol, detection or discrimination. 
		CAUTION: The tongue should gently protrude from mouth such that the tongue tip meets the inferior edge of the lower lip. The participant should not be straining to stick their tongue out as far as possible or it will fatigue quickly and could alter testing results.</li>
	</ol>
	</li>
</ol>
2. Detection threshold estimates
<ol>
	<li>Instruct participant, &#34;For this test, you will hear me say &#39;Trial 1&#39; and &#39;Trial 2&#39;. You will feel a point of pressure in one of these trials. If you think you feel a point of pressure in trial 1, put up 1 finger. If you think you feel a point of pressure in trial 2, put up 2 fingers. If you&#39;re not sure, make your best guess. Pressure will always be applied in one of the two trials.&#34;</li>
	<li>Identify the starting point for testing: Determine the starting point for all participants for the detection threshold estimates. Published protocol begins at 1.0 g. Researchers strongly suggest the experimenter begins at a suprathreshold level to be sure that the majority of participants can easily identify the first target force.</li>
	<li>Tell participant to close their eyes and start the trials
	<ol>
		<li>Say Trial 1 and pause. Say Trial 2 and pause. Be sure to deliver the pressure in one of these trials such that the monofilament is pressed to the tongue surface until the monofilament buckles. Hold for a second and release.
		<ol>
			<li>Use a random number generator to create a series of 1 or 2. Follow this series to randomly present the stimulus in Trial 1 or Trial 2 (See Supplementary Files 3 &#38; 4). Do not follow a pattern.</li>
			<li>Be deliberate and intentional when applying the pressure such that the stimulus is always clearly delivered in Trial 1 or Trial 2 with a 1-s pause before and after when the Trial is said and when the stimulus is delivered.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Record the participant&#39;s response (See Supplementary Files 1-4 for examples).</li>
	<li>Continue testing using a 3-down/1-up decision rule to select the next stimulus.
	<ol>
		<li>Move up to the next monofilament in the series after any incorrect or &#34;missed&#34; response.</li>
		<li>Ensure that the participant gets three correct responses in a row for the experimenter to move down to the next monofilament in the series.</li>
	</ol>
	</li>
	<li>Stopping point
	<ol>
		<li>Stop testing when a participant has reached his/her stopping point. This is defined as the point when a participant has crossed over or received the test stimulus from the same target monofilament a total of five times.</li>
		<li>If the participant reaches the lowest available testing target (0.008g), continue delivering this target for 5 consecutive sets before stopping.</li>
		<li>If the participant reaches the highest testing target (15 g) and cannot correctly identify the target trial, discontinue testing.</li>
	</ol>
	</li>
	<li>Estimate approximately 5-10 min to complete testing to determine a detection threshold estimate for midline tongue. 
	NOTE: Stopping points apply regardless of whether the participant gets that last trial correct or incorrect.</li>
</ol>
3. Discrimination Threshold Estimates
<ol>
	<li>To complete discrimination threshold testing, follow a similar protocol to detection threshold testing.</li>
	<li>Instruct participant, &#34;For this test, you will still hear me say &#39;Trial 1&#39; and &#39;Trial 2&#39; but this time you will feel a point of pressure in both trials. I want you to identify which trial contained the stronger or harder point of pressure. If you think the harder/stronger pressure was in trial 1, put up 1 finger. If you think you the harder/stronger pressure was in trial 2, put up 2 fingers. If you&#39;re not sure, make your best guess.&#34;</li>
	<li>Identify a starting point
	<ol>
		<li>Begin test at three monofilament levels above the stopping point for their estimated detection threshold. Use the target stimulus and the monofilament immediately below it in force as the two discrimination stimuli.</li>
		<li>Follow this example: If the participant reached a stopping point of 0.008 g, start his/her discrimination testing at 0.07g as the target stimulus and the monofilament directly below it (0.04 g) as the second stimulus delivered.</li>
	</ol>
	</li>
	<li>Tell the participant to close their eyes and start the trials.
	<ol>
		<li>Deliver the two stimuli after clearly stating Trial 1 or Trial 2. Again, this should be randomized, to avoid a pattern.</li>
	</ol>
	</li>
	<li>Record the participant&#39;s response (See Supplementary Files 1-4 for examples).</li>
	<li>Continue testing using the same 3-down/1-up and stopping point as used in the protocol for Detection Thresholds.
	<ol>
		<li>Continue testing with 0.008g with no stimulus delivered in the second trial if the participant reaches 0.008 g during discrimination testing (lowest manufactured level).</li>
		<li>Offer the participant a drink of water if they miss two target stimuli in a row.</li>
	</ol>
	</li>
	<li>Estimate approximately 5-10 min to complete a discrimination threshold estimate for midline tongue.</li>
</ol>
4. Scoring
<ol>
	<li>Record all target stimuli and participant response data from threshold estimate testing.
	<ol>
		<li>Record the stopping point for each individual for both detection and discrimination</li>
		<li>Record the number of trials it took for the participant to successfully complete testing</li>
		<li>Record the participant&#39;s threshold average by finding the first time the participant was given the eventual stopping point stimulus. Add all the target stimuli delivered between the first instance of the stopping point target force and the last and divide by the total number of trials. This gives a threshold estimate average that takes in to account the variability within a participant.</li>
	</ol>
	</li>
	<li>Set up data recording sheets using one of the two suggested options. Find examples of completed sheets using the same values can be found in the Supplementary Materials. The first option (Supplementary Files 1 &#38; 2) provides a data sheet and completed example in which the participant&#39;s responses and threshold estimate can be easily visualized and recorded on one sheet. The second option (Supplementary Files 3 &#38; 4) provides a data sheet with randomized order for presenting the test stimuli. A separate sheet is needed for each test - detection or discrimination.</li>
</ol>
5. Cleaning equipment
<ol>
	<li>Do not close the monofilaments during testing or immediately following testing until they are cleaned.</li>
	<li>Place the nylon end of the monofilament between an alcohol prep pad (70% alcohol) and gently squeeze the alcohol pad together while pulling the monofilament through.</li>
	<li>Leave the monofilament in the open position, repeat the cleaning process on each monofilament used.</li>
	<li>Allow the monofilaments to air dry in the open position.</li>
	<li>Close the monofilaments and store them in a clean and dry environment, away from direct sunlight, as described in the manufacturer&#39;s directions.</li>
</ol>

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The authors Nicole M. Etter, Scott P. Breen, and Maya I.M. Alcala have no conflicts to disclose; Breen and Alcala were students at the time the work was performed and are now employed in the food industry. The authors John E. Hayes and Gregory R. Ziegler have each received speaking or consulting fees from non-profit organizations and corporate clients in the food industry. Additionally, the Sensory Evaluation Center (Hayes, Director) at Penn State routinely conducts taste tests for the food industry to facilitate experiential learning for students. None of these organizations have had any role in study conception, design or interpretation, or the decision to publish these data.

In previous studies, researchers observed that periodic rewetting of the tongue was an important step. For example, participants who did not regularly rewet the tongue demonstrated poorer sensory acuity. While no attempts were made to systematically determine the optimal rewetting interval, experience suggests experimenters should ask participants to rewet the tongue every few trials by bringing the tongue back into the mouth and/or having a small sip of water. Although work by Verrillo and colleagues found that vibrotactile detection thresholds were not impacted by skin hydration, these studies were completed on the hand, forearm, and cheek - not the tongue23. Because the tongue is consistently bathed in saliva, the change from wet to dry could alter sensory acuity. In fact, in work assessing salivary production and flavor appreciation in older adults, researchers found a relationship between decreased salivation and perception of umami flavor24. Aside from lingual moisture, changes in point pressure detection and discrimination threshold estimates can be impacted by a number of individual factors, including advancing age22 or changes in cognition25 which may impact attention to task. Additionally, some previous studies have either excluded smokers or asked participants to refrain from smoking for a period of time prior to testing26.
A blindfold was not used in this protocol as prior experience suggested participants find it distracting to be blindfolded with their mouths open and tongue out. In pilot testing of the protocol, participants were startled by the stimuli or repeatedly told researchers they couldn&#39;t concentrate. Therefore, participants were simply told to close their eyes. If a participant opened their eyes during a set of stimuli presentations, that set can be repeated. Other studies in the field have chosen to use a blindfold20; however, use of a blindfold may not significantly change the results when comparing across studies11.
During initial trials of this protocol, researchers selected a ceiling of 15.0 g. Although available monofilaments go up to 300 g, a ceiling was selected a priori to prevent the risk of damaging the skin. Additionally, when testing an area like the tongue for which there is no internal skeletal structure, application of monofilaments higher than 15 g were found to move the entire tongue muscle which could activate sensory nerve endings in surrounding locations17. In the representative data sample, many healthy young adults were able to sense the 0.008 g target monofilament - the lowest manufactured Von Frey hair monofilament. Alternatively, Cochet-Bonnet contact aesthesiometers have been used to measure sensitivity of the cornea. It is possible this device may provide an opportunity to test at levels less than 0.008 g; however, there are unresolved questions related to calibration of Cochet-Bonnet devices and ability to share findings across studies27.
This protocol is adapted from recent work by Etter and colleagues17 with a few key differences. In Etter&#39;s original protocol, threshold estimates were not averaged across trials. This may have missed some of the variability in participant responses. Additionally, Etter&#39;s original protocol was focused on using the tongue for speech-related movements, and therefore assessed point pressure of tongue at the right and left lateral edges just posterior to tongue tip versus midline tongue locations that may be more important for texture appreciation and swallowing28,29.
Future applications of this testing protocol may include studies of individuals with a variety of central and/or peripheral nervous system damage, as well as those with damage to the oral mucosa either from trauma, tumors, or post radiation therapy. For example, researchers recently evaluated individuals post-stroke who were experiencing oral dysphagia and noted increase thresholds, or decreased sensation in people with stroke as compared to healthy controls30. Additionally, in a review paper by Kaplan and colleagues, patients with xerostomia for a variety of medical reasons reported changes in mastication and swallowing, decreased salivary flow rates, and changes to oral mucosa31. Future work assessing the impact of these changes on tactile point pressure assessments would be beneficial to the field.
Finally, using this protocol does not require any mark to be made to the tongue to ensure exact testing location is repeated with each trial. This was originally done to increase clinical application of this protocol to medical and outpatient clinic locations. Reliability testing by Etter colleagues demonstrated high test-retest results without marking the tongue17. However, it is possible to mark the tongue using a dye to ensure a consistent target location as illustrated in a recent study by Santagiuliana and colleagues26. The appropriateness of using food dye to mark the tongue may vary depending on testing location and research question.

Any time we eat or drink, we determine the acceptability of a food based on multiple sensory percepts like taste, smell, and texture. Texture is not merely a physical property of the food; rather it arises from interactions of the food with the somatosensory (pressure and touch) system in the mouth. Flavor is the integrated percept that arises from multiple neuronal inputs, including taste, smell and oral touch1. Perception of food flavor, including pressure and texture information, is a key driver of food choice. Both common sense and data from numerous studies suggest people eat what they like2. However, in practice, this relationship between texture and food selection is more nuanced, as individuals avoid what they dislike3. Food selection is a behavior based on both cognitive choices and prior sensory experiences. Individual differences in smell and taste have a demonstrated ability to influence ingestive behavior4 with large variation across individuals to the point of influencing chronic diet choices5. Thus, two people may eat the same food but react very differently to it in regard to the degree of liking of that food. However, the degree to which this food preference is driven by individual differences in oral somatosensory function, including tactile and texture appreciation, remains understudied. In fact, the influences and mechanisms of oral point pressure and texture perception are much less understood relative to other oral sensory systems. Recent data suggests there may be important individual differences in oral tactile sensation abilities6,7,8. Because oral touch information is internalized and individual in nature9, it could drive individual preferences and influence food choices.
Measurements of peripheral nerve function through cutaneous pressure assessments require activation of slowly and rapidly adapting mechanoreceptors in the skin, including Merkel cells, Meissner corpuscles, Ruffini corpuscles and Pacinian corpuscles - with a high representation of slowly adapting mechanoreceptors in the face, lips, and oral mucosa that are responsive to pressure and slow stretch10,11. One relatively time and cost effective means of assessing oral tactile sensation is through the use of point-pressure assessments using Von Frey Hair (VFH) monofilaments. VFH monofilaments are widely used to assess peripheral nerve function through point pressure detection across the body, but specifically in glabrous (non-hairy) skin, including fingertip, hands, and feet12,13,14,15,16. In fact, testing with VFH monofilaments has demonstrated high test-retest reliability in the lips, tongue, and feet in healthy young, aging, and disordered populations16,17.
Assessing oral point-pressure detection and discrimination is potentially one part of a full assessment of a person&#39;s individual oral touch profile. Better understanding of individual oral touch responses could inform food choice preferences in healthy and disordered populations. A complete assessment of individual oral touch and texture perception could allow clinicians to improve recommendations for healthy aging adults as well as people with specialized (dysphagia) diets to meet their individual nutrition needs necessary for health and wellness. Select clinical populations with dysphagia, as well as typically aging adults, may require altered food textures to achieve adequate and safe nutrition; however, these clinical populations may also reject foods based on texture and mouth feel preferences18,19. Better understanding of the mechanisms underpinning food preferences that drive food choices, eating behavior, and diet compliance may provide novel targets for intervention, both at a systems level and an individual level.
The purpose of this assessment protocol is to characterize individual differences in oral point pressure (OPP) sensitivity by establishing detection and discrimination threshold estimates at midline tongue. This protocol uses Von Frey Hair monofilaments, commercially-available devices, to complete a relatively cost and time efficient assessment. Quantitative assessments of oral point pressure somatosensation using Von Frey hair monofilaments and this protocol were recently shown to be reliable in a cohort of healthy, young adults17 for lateral edge of the lips and tongue as a prelude to future work in speech and speech disorders. However, the present protocol and recent work has focused on midline tongue due to its involvement with manipulating foods for tasting and safe and efficient swallowing20.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>plastic cup for drinking water</td>
			<td>various</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Aesthesio Tactile Sensory Evaluator Kit</td>
			<td>DanMic Global LLC, San Jose CA</td>
			<td>514000-20C</td>
			<td></td>
		</tr>
	</tbody>
</table>

assessment of midline lingual point-pressure somatosensation using von frey hair monofilaments

Detection and discrimination threshold estimates for oral point pressure are assessed using Von Frey Hair monofilaments. Consistent with previously published protocols, threshold estimates are determined using a two-interval forced choice (2-IFC) paradigm with a three down/one up approach. Detection threshold estimates determine the mean force in which a participant can identify the presence of pressure. During the detection threshold procedure, the participant is instructed to choose which of two sequentially presented observation intervals contained the tactile test stimulus. If the participant performs three correct detections in a row (i.e., 3 &#39;hits&#39;), the researcher decreases the stimulus to the next lower target force level. With one incorrect detection (a &#39;miss&#39;), the researcher increases the force delivered to the next higher level. This threshold estimation approach is known as a 3-down/1-up adaptive staircase. Reponses are recorded on a paper ballot, and a participant&#39;s estimated threshold is defined as the geometric mean of five reversals. During the discrimination threshold procedure, the participant is asked to make a choice between two serially presented stimuli as to which is the &#34;harder&#34; or &#34;stronger&#34; pressure. The same scoring of &#39;hits&#39;, &#39;misses&#39;, and stopping points are used. Detection and discrimination testing for oral point pressure at tongue midline takes approximately 20 min to complete. Using these commercially-available clinical tools, individual touch sensation profiles for the midline tongue can be achieved in a relatively time and cost effective means.

When interpreting the results, it is important to remember that lower threshold estimates indicate greater sensory acuity. The use of a forced choice procedure helps separates criterion response bias (i.e., a willingness to say yes) from underlying sensitivity of the system. A lower threshold indicates an individual can perceive a lighter stimulus than those with a higher threshold estimate. Higher threshold estimates indicate decreased sensory acuity. A higher threshold estimate indicates an individual requires a larger input to cognitively perceive the stimulus. Higher threshold estimates could be due to difficulty in cognitively completing the task16,21 or due to peripheral damage associated with advancing age or disorder to the cutaneous surface of the tongue or peripheral nerves22.
Data is still being collected to further develop normative data from a sample of nominally healthy adults. However, a sample of data on individual differences in oral somatosensory function was recently published7. Combining previously published data with additional data, a total of 111 healthy participants (34M:77F; mean 32.1 years, range 18 to 68 years) completed at least one portion of the detection and/or discrimination threshold estimate protocol described here.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td colspan="2">Detection</td>
			<td colspan="2">Discrimination</td>
		</tr>
		<tr>
			<td></td>
			<td colspan="2">(n= 51)</td>
			<td colspan="2">(n= 107)</td>
		</tr>
		<tr>
			<td>Location</td>
			<td>M (SD)</td>
			<td>Range</td>
			<td>M (SD)</td>
			<td>Range</td>
		</tr>
		<tr>
			<td>Midline Tongue</td>
			<td>0.0157 (0.022)</td>
			<td>0.008-0.16</td>
			<td>0.600 (1.812)</td>
			<td>0.02-15</td>
		</tr>
	</tbody>
</table>
Table 1: Detection and discrimination threshold estimates for pressure point sensitivity on midline tongue. The geometric mean, standard deviation and range are provided from our representative sample. Fifty one participants completed detection threshold estimate testing (10M:41F, mean 37.1 years). A total of 107 participants completed discrimination threshold estimate testing (31M: 76F, mean 31.9 years).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/60656/60656fig1.jpg" /> 
Figure 1: This figure presents data for midline lingual point pressure detection threshold estimate (g) by participant age (years). Note the y-axis ranges from 0.0 - 0.25 g. Participants across this healthy age span demonstrated low thresholds for point-pressure detection. <a href="https://www.jove.com/files/ftp_upload/60656/60656fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/60656/60656fig2.jpg" /> 
Figure 2: This figure provides data for midline lingual point pressure discrimination threshold estimate (g) by participant age (years). Note the y-axis ranges from 0.0 - 16.0 g. Participants across this healthy age span demonstrated increased variability in discrimination threshold estimates as compared to detection threshold estimates. <a href="https://www.jove.com/files/ftp_upload/60656/60656fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
Supplementary Materials 
Two potential options for setting up data recording sheets are available in the Supplementary Files. Data can easily be recorded and visualized using a one page data collection sheet (Supplementary files 1 &#38; 2). On this sheet, both detection and discrimination data can be recorded in their respective sections. The list of Von Frey Hair monofilament targets in grams (g) and the color of the pen are included on the left hand side. An asterisk (*) has been placed next to the 1.000 g target in the &#39;Detection&#39; section to remind testers of the starting point for testing using this protocol. The trial numbers are listed across the bottom to easily identify the total number of trials needed. The authors suggest following the key listed on the bottom right to mark correct and incorrect participant responses. A second data recording option is provided in Supplementary Files 3 &#38; 4. The series number is noted in the column marked #. The target or test stimuli is recorded in grams in the column labeled &#39;Target (g)&#39;. The next two columns are labeled &#39;Trial 1&#39; and &#39;Trial 2&#39; to indicate in which the trial the tester should deliver the test stimuli. This pattern was created using a random number generator. Experimenters will present the test stimuli in the trial with the &#34;X&#34; in it. For example, in the first series, the target stimuli would be delivered in the second trial because the &#34;X&#34; is under the Trial 2 heading. Finally, in the last column, the experimenter can record the participant&#39;s response as correct (Y) or incorrect (N). This column can also be used to note the number of presentations of that target to aide in identifying the stopping point.
Supplementary File 1. <a href="https://www.jove.com/files/ftp_upload/60656/supplementaryfile1.pdf" target="_blank">Please click here to view this file.</a>
Supplementary File 2. <a href="https://www.jove.com/files/ftp_upload/60656/supplementaryfile2.pdf" target="_blank">Please click here to view this file.</a>
Supplementary File 3. <a href="https://www.jove.com/files/ftp_upload/60656/supplementaryfile3.pdf" target="_blank">Please click here to view this file.</a>
Supplementary File 4. <a href="https://www.jove.com/files/ftp_upload/60656/supplementaryfile4.pdf" target="_blank">Please click here to view this file.</a>

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Assessment of Midline Lingual Point-Pressure Somatosensation Using Von Frey Hair Monofilaments

This work describes a standard method to assess tactile sensation at the midline of the tongue tip. Using Von Frey Hair (VFH) monofilaments, this protocol provides estimates of detection and discrimination threshold estimates for oral point pressure (OPP).

Detection and discrimination threshold estimates for oral point pressure are assessed using Von Frey Hair monofilaments. Consistent with previously ...

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8.1K Views.  The Pennsylvania State University. This work describes a standard method to assess tactile sensation at the midline of the tongue tip. Using Von Frey Hair (VFH) monofilaments, this protocol provides estimates of detection and discrimination threshold estimates for oral point pressure (OPP).

Video: Assessment of Midline Lingual Point-Pressure Somatosensation Using Von Frey Hair Monofilaments

Assessment of Age-related Changes in Cognitive Functions Using EmoCogMeter, a Novel Tablet-computer Based Approach

The main goal of this study was to assess the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on cognitive functions across the lifespan in a sample of 378 healthy subjects (age range 18-89 years). Consistent with previous findings we found an age-related cognitive decline across a wide range of neuropsychological domains (memory, attention, executive functions), thereby proving the usability of our tablet-based application. Regardless of prior computer experience, subjects of all age groups were able to perform the tasks without instruction or feedback from an experimenter. Increased motivation and compliance proved to be beneficial for task performance, thereby potentially increasing the validity of the results. Our promising findings underline the great clinical and practical potential of a tablet-based application for detection and monitoring of cognitive dysfunction.

We tested the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on cognition. Results show an age-related cognitive decline, thereby proving the usability of our application. Findings underline the great clinical and practical potential of a tablet-based application for detection and monitoring of cognitive dysfunction.

The main goal of this study was to assess the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on ...

Behavioral Assessment of the Aging Mouse Vestibular System

Age related decline in balance performance is associated with deteriorating muscle strength, motor coordination and vestibular function. While a number of studies show changes in balance phenotype with age in rodents, very few isolate the vestibular contribution to balance under either normal conditions or during senescence. We use two standard behavioral tests to characterize the balance performance of mice at defined age points over the lifespan: the rotarod test and the inclined balance beam test. Importantly though, a custom built rotator is also used to stimulate the vestibular system of mice (without inducing overt signs of motion sickness). These two tests have been used to show that changes in vestibular mediated-balance performance are present over the murine lifespan. Preliminary results show that both the rotarod test and the modified balance beam test can be used to identify changes in balance performance during aging as an alternative to more difficult and invasive techniques such as vestibulo-ocular (VOR) measurements.

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 ...

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.

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 ...

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 ...

Combined Shuttle-Box Training with Electrophysiological Cortex Recording and Stimulation as a Tool to Study Perception and Learning

Shuttle-box avoidance learning is a well-established method in behavioral neuroscience and experimental setups were traditionally custom-made; the necessary equipment is now available by several commercial companies. This protocol provides a detailed description of a two-way shuttle-box avoidance learning paradigm in rodents (here Mongolian gerbils; Meriones unguiculatus) in combination with site-specific electrical intracortical microstimulation (ICMS) and simultaneous chronical electrophysiological in vivo recordings. The detailed protocol is applicable to study multiple aspects of learning behavior and perception in different rodent species.
Site-specific ICMS of auditory cortical circuits as conditioned stimuli here is used as a tool to test the perceptual relevance of specific afferent, efferent and intracortical connections. Distinct activation patterns can be evoked by using different stimulation electrode arrays for local, layer-dependent ICMS or distant ICMS sites. Utilizing behavioral signal detection analysis it can be determined which stimulation strategy is most effective for eliciting a behaviorally detectable and salient signal. Further, parallel multichannel-recordings using different electrode designs (surface electrodes, depth electrodes, etc.) allow for investigating neuronal observables over the time course of such learning processes. It will be discussed how changes of the behavioral design can increase the cognitive complexity (e.g. detection, discrimination, reversal learning).

Shuttle-box avoidance learning is well-established in behavioral neuroscience. This protocol describes how shuttle-box learning in rodents can be combined with site-specific electrical intracortical microstimulation (ICMS) and simultaneous chronical in vivo recordings as a tool to study multiple aspects of learning and perception.

Shuttle-box avoidance learning is a well-established method in behavioral neuroscience and experimental setups were traditionally custom-made; the ...

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 ...

Assessment of Social Transmission of Food Preferences Behaviors

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy aging groups. For example, olfactory dysfunction in AD can present as impairment in olfactory recognition, emerging during early stages of the disease and worsening while the disease progresses. The social transmission of food preferences (STFP) task is based on a rudimentary form of communication between rodents concerning distant foods dependent on the transmission of olfactory cues. Healthy wild-type mice would prefer to eat a novel, flavored food that was previously cued by a conspecific, and this food preference would be hampered in transgenic AD mice, such as the APP/PS1 model. Indeed, a strong preference for the cued food in C57Bl6/J mice of 3 months of age was found, and this was reduced in 3 months old transgenic APP/PS1 mice. In summary, STFP task could be a powerful measure to be integrated in present subclinical detection assays of AD.

This paper presents a protocol for the investigation of social transmission of food preference in mice. The advantages and possible applications for this procedure, for instance, in detecting early changes in AD mouse models, are highlighted. To conclude, interpretation of the results in light of critical details are discussed.

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy ...

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 ...

Multi-Modal Signals for Analyzing Pain Responses to Thermal and Electrical Stimuli

The assessment of pain relies mostly on methods that require a person to communicate. However, for people with cognitive and verbal impairments, existing methods are not sufficient as they lack reliability and validity. To approach this problem, recent research focuses on an objective pain assessment facilitated by parameters of responses derived from physiology, and video and audio signals. To develop reliable automated pain recognition systems, efforts have been made in creating multimodal databases in order to analyze pain and detect valid pain patterns. While the results are promising, they only focus on discriminating pain or pain intensities versus no pain. In order to advance this, research should also consider the quality and duration of pain as they provide additional valuable information for more advanced pain management. To complement existing databases and the analysis of pain regarding quality and length, this paper proposes a psychophysiological experiment to elicit, measure, and collect valid pain reactions. Participants are subjected to painful stimuli that differ in intensity (low, medium, and high), duration (5 s / 1 min), and modality (heat / electric pain) while audio, video (e.g., facial expressions, body gestures, facial skin temperature), and physiological signals (e.g., electrocardiogram [ECG], skin conductance level [SCL], facial electromyography [EMG], and EMG of M. trapezius) are being recorded. The study consists of a calibration phase to determine a subject&#8217;s individual pain range (from low to intolerable pain) and a stimulation phase in which pain stimuli, depending on the calibrated range, are applied. The obtained data may allow refining, improving, and evaluating automated recognition systems in terms of an objective pain assessment. For further development of such systems and to investigate pain reactions in more detail, additional pain modalities such as pressure, chemical, or cold pain should be included in future studies. Recorded data of this study will be released as the &#8220;X-ITE Pain Database&#8221;.

This article focuses on the experimental elicitation of pain through heat (thermal) and electrical stimulation while recording physiological, visual, and paralinguistic responses. It aims at collecting valid multimodal data for analyzing pain based on its intensity, quality, and duration.&#160;

The assessment of pain relies mostly on methods that require a person to communicate. However, for people with cognitive and verbal impairments, existing ...

Assessment of Sexual Behavior of Male Mice

Sexual behavior is highly species-specific. Although rodents have slightly different sexual behaviors, mice and rats have a similar sexual behavioral pattern. The purpose of this article is to describe the hormone-induced estrus ovariectomized female model and the experimental procedure for the assessment of sexual behavior of male mice. The most important sexual behavioral elements are demonstrated in the video and illustrations. The critical steps, advantages, and limitations of the sexual behavior test are explained as well. Finally, the behavior parameters are presented, and mounting, intromission, and ejaculation processes in mating are distinguished. Behavioral parameters are assessed in terms of the occurred duration and counts during the test period.

This article describes how to perform sexual behavior tests in male mice.

Sexual behavior is highly species-specific. Although rodents have slightly different sexual behaviors, mice and rats have a similar sexual behavioral ...