We thank J. M. C. D. Meijer of theTechnical Development Studio of Wageningen University and Research for his help in the development of the mEETr tray. This research was funded by the 4 Dutch Technical Universities, 4TU- Pride and Prejudice project.

This pilot study was approved by the METC of Wageningen University prior to starting the project.
CAUTION: All the participants contributing to this project provided an informed consent, including the approval of video images showing visible and recognizable faces.
1. Sample preparation and participant consent
<ol>
	<li>Prepare a juice (glass or cup), fruit yoghurt (bowl), and fruit pieces (plate). 
	NOTE: These foods are selected for demonstration purposes only (Figure 2).</li>
	<li>Recruit a participant or a volunteer who agrees to participate in the study.</li>
	<li>Exclude the participants wearing glasses (who cannot use contact lenses) and/or having facial hair (beard or mustache) to avoid measurement errors.</li>
	<li>Inform the participants about the study and the data collection (data storage, accessibility). Obtain separate permissions in case of non-anonymous video recordings. Get the signature of the participant on the informed consent before collecting data.</li>
</ol>
2. Device and measurement location set-up
NOTE: This protocol is suited for data collection in a controlled (eating laboratory) setting.
<ol>
	<li>Make sure that the light in the room is evenly distributed-avoid shadows on participants&#39; faces.</li>
	<li>Avoid the background noise on the video recordings due to the presence of individuals other than the participant.</li>
	<li>Seat the participant on a chair before a table; with tabletop located just below the participant&#39;s chest.</li>
	<li>Connect the wireless receiver of the tray and the webcam to a laptop.</li>
	<li>Start up the laptop. Ensure that the laptop has the following specifications: CPU i7-10750H, SSD M.2 512 GB, Memory 1x 16 GB, DDR4 2933 MHz non-ECC-memory, Operating system 64 bit.</li>
	<li>Switch on the tray and ensure that there is charge in the tray (green light).</li>
	<li>Open the connector program (dos), the receiver, and the processor software program together with the dashboard, respectively.</li>
	<li>Check the incoming image quality in the processor program (Figure 3). 
	NOTE: To detect the eating behavior, the image quality should be within the last quarter of the task bar (green); as close to 100% green as possible. Shadow forming may lead to low image quality.</li>
	<li>Make sure the image frame is correct to prevent poor image quality. Ensure that the participant&#39;s head (above the cranium) till chest, including arms and shoulders are clearly visible.</li>
</ol>
3. Weighing system and data transport
<ol>
	<li>Validate the measures prior to the use of the mEETr for the first time. 
	NOTE: The mEETr device consists of a regular commercially available dining tray (fiber enforced epoxy dinner tray) with three built-in weighing stations (Figure 2).</li>
	<li>To validate the set-up, ensure that the tray continuously measures the weight of a plate, bowl, and drinking glass. 
	NOTE: The precision of the weighing scale across the whole range should be 0.3%.</li>
	<li>Do not place too much weight on each weighing platform. The maximum weight for the largest platform (dinner plate) is 1.5 kg. The maximum weight of the two smaller weighing platforms (bowl and glass) is 800 g. The minimum weight that can be accurately measured is 1 g for each weighing station.</li>
	<li>Make sure that the plate, the cup, and the bowl are not resting on the platform or the surrounding tray. Make use of the center ring to avoid this. 
	NOTE: Each weighing station consists of three triangle positioned force sensors that act together as one scale. A triangle position was chosen to balance weight.</li>
	<li>Make sure to keep the tray dry. The tray includes a 50 mm thin base panel (central circuit board) below the tray that contains the electronics.</li>
	<li>For data transfer, make sure that the tray connects to a wireless receiver. 
	NOTE: Transfer the weighing data at a 1 s interval via a short-range radio signal (about 1 m distance). Connect the receiver to a personal computer (PC) via an USB port.</li>
	<li>The three force sensors measure the forces (or weights), sum them up, and convert them to a calibrated weight value.</li>
	<li>Recharge the tray after each use. 
	NOTE: The tray is powered by an internal battery pack and can be charged with a USB charger. An on/off slide switch is located near to the USB socket. A full battery charge provides for about 20 h of use.</li>
	<li>Do not clean the tray in a dishwasher; the tray is not dishwasher proof. Clean the tray using a cleaning spray. Ensure that the tray is kept clean and dry. Leak channels along the platforms drain liquid spills.</li>
</ol>
4. Participant explanations and start of observation
<ol>
	<li>Place the mEETr in front of the participant.</li>
	<li>Instruct the participant to 1) eat as much or as little as he/she wants, 2) look straight into the webcam while eating, and 3) do not put hands in front of the face while eating.</li>
	<li>Start a new observation in the receiver software. Log the date, participant number, participant&#39;s gender, age, and anthropometric data, such as weight and height. Include additional information such as the study condition and the study visit in the observation name.</li>
	<li>Press Record in the receiver software to record the observation.</li>
	<li>Activate the dashboard in order to check the video recordings and the incoming data during data collection (Figure 4).</li>
	<li>Prior to the recording, ask the participant to 1) raise the card with the participant number, and 2) raise their hand at the start and end of the meal.</li>
	<li>End the observation when the participant finishes eating. It takes 2 min to transfer all the data to a spreadsheet.</li>
	<li>This is the end of the session for the participant.</li>
	<li>Disconnect the webcam and the tray-receiver from the laptop and clean it with a cleaning tissue or cleaning spray.</li>
</ol>
5. Evaluation and transfer of data
<ol>
	<li>Open the last observation in the receiver software. Automated measures of eating behavior are stored under the heading Data. Click on Export Data to extract the raw data. The subsequent output file contains data on the participant number, real time, relative (to start) time, and eating behavior variables (number of bites, number of chews, chewing duration) per test participant. 
	NOTE: All behaviors are time stamped. In the receiver software, additional external data of the tray can be extracted, for example, the data on the weight of each of the three trays. The data is recorded 10 times per second and transferred. The tray data collection time is synchronized with the eating behavior recordings.</li>
	<li>Summarize and visualize the results in different bar charts within the program itself. Export the results as raw data in log files (.xsl) (Figure 5).</li>
	<li>Export the log files to a spreadsheet and perform the data analysis using the statistical program of preference.</li>
	<li>Clean the data before data analysis. 
	&#8203;NOTE: Due to the distortions of pressing with cutlery on the plates (causing an increase in weight), weighing data of the tray needs to be cleaned to a Kaplan Meier curve with step size indicating bite size, the step length indicating time between bites. The beginning of the curve indicates start-weight, the last step indicates end-weight) as follows.
	<ol>
		<li>Smoothen over the timepoints to measurements per second to filter out extreme values.</li>
		<li>Set 5 g boundary, detect weight plateaus (i.e., no change within +/- 5 g), and weight changes (changes over time larger than 5 g) to indicate bite sizes and portion changes.</li>
		<li>Exclude weight increase due to cutlery remaining on the plate. 
		NOTE: The output is the total weight changes per weight station begin and end of meal (= meal size), average bite size, and bites per min.</li>
	</ol>
	</li>
	<li>To determine eating rate (g/sec) and bite size (g/bite) changes over the course of the meal, manually integrate the tray weight data and the eating behavior (Figure&#160;6,&#160;Figure 7,&#160;Figure 8,&#160;Figure 9,&#160;Figure&#160;10).</li>
</ol>

<ol>
	<li>Burrows, T. L., Ho, Y. Y., Rollo, M. E., Collins, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validity+of+dietary+assessment+methods+when+compared+to+the+method+of+doubly+labeled+water:+A+systematic+review+in+adults.">Validity of dietary assessment methods when compared to the method of doubly labeled water: A systematic review in adults.</a> Frontiers in Endocrinology. 10, 850 (2019).</li><li>Brouwer-Brolsma, E. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dietary+intake+assessment:+From+traditional+paper-pencil+questionnaires+to+technology-based+tools.+Environmental+software+systems.+Data+science+in+action.">Dietary intake assessment: From traditional paper-pencil questionnaires to technology-based tools. Environmental software systems. Data science in action.</a> Advances in Information and Communication Technology. 554, (2020).</li><li>Palese, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+nursing+home+environment+can+maximise+eating+independence+among+residents+with+cognitive+impairment?+Findings+from+a+secondary+analysis.">What nursing home environment can maximise eating independence among residents with cognitive impairment? Findings from a secondary analysis.</a> Geriatric Nursing. 41 (6), 709-716 (2020).</li><li>Krop, E. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+oral+processing+on+appetite+and+food+intake+-+A+systematic+review+and+meta-analysis.">Influence of oral processing on appetite and food intake - A systematic review and meta-analysis.</a> Appetite. 125, 253-269 (2018).</li><li>Nicolas, E., Veyrune, J. L., Lassauzay, C., Peyron, M. A., Hennequin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+video+versus+electromyography+for+chewing+evaluation+of+the+elderly+wearing+a+complete+denture.">Validation of video versus electromyography for chewing evaluation of the elderly wearing a complete denture.</a> Journal of Oral Rehabilitation. 34 (8), 566-571 (2007).</li><li>Sabin, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+treatment+for+childhood+obesity+using+Mandometer&#174;+technology.">A novel treatment for childhood obesity using Mandometer&#174; technology.</a> International Journal of Obesity. 7, (2006).</li><li>Hermsen, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+Smart+fork+to+decelerate+eating+rate.">Evaluation of a Smart fork to decelerate eating rate.</a> Journal of the Academy of Nutrition and Dietetics. 116 (7), 1066-1068 (2016).</li><li>vanden Boer, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+splendid+eating+detection+sensor:+Development+and+feasibility+study.">The splendid eating detection sensor: Development and feasibility study.</a> JMIR mHealth and uHealth. 6 (9), 170 (2018).</li><li>Papapanagiotou, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+chewing+detection+system+based+on+ppg,+audio,+and+accelerometry.">A novel chewing detection system based on ppg, audio, and accelerometry.</a> IEEE Journal of Biomedical and Health Informatics. 21 (3), 607-618 (2016).</li><li>Ioakimidis, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Description+of+chewing+and+food+intake+over+the+course+of+a+meal.">Description of chewing and food intake over the course of a meal.</a> Physiology &amp; Behavior. 104 (5), 761-769 (2011).</li><li>Ruiz, L. D., Zuelch, M. L., Dimitratos, S. M., Scherr, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adolescent+obesity:+Diet+quality,+psychosocial+health,+and+cardiometabolic+risk+factors.">Adolescent obesity: Diet quality, psychosocial health, and cardiometabolic risk factors.</a> Nutrients. 12 (1), 43 (2020).</li><li>Forde, C. G., van Kuijk, N., Thaler, T., de Graaf, C., Martin, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oral+processing+characteristics+of+solid+savoury+meal+components,+and+relationship+with+food+composition,+sensory+attributes+and+expected+satiation.">Oral processing characteristics of solid savoury meal components, and relationship with food composition, sensory attributes and expected satiation.</a> Appetite. 60 (1), 208-219 (2013).</li><li>Weijzen, P. L. G., Smeets, P. A. M., de Graaf, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sip+size+of+orangeade:+effects+on+intake+and+sensory-specific+satiation.">Sip size of orangeade: effects on intake and sensory-specific satiation.</a> British Journal of Nutrition. 102 (07), 1091-1097 (2009).</li><li>Zijlstra, N., de Wijk, R. A., Mars, M., Stafleu, A., de Graaf, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+bite+size+and+oral+processing+time+of+a+semisolid+food+on+satiation.">Effect of bite size and oral processing time of a semisolid food on satiation.</a> The American Journal of Clinical Nutrition. 90 (2), 269-275 (2009).</li><li>Bolhuis, D. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Slow+food:+sustained+impact+of+harder+foods+on+the+reduction+in+energy+intake+over+the+course+of+the+day.">Slow food: sustained impact of harder foods on the reduction in energy intake over the course of the day.</a> PloS One. 9 (4), 93370 (2014).</li><li>Grinyer, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+anonymity+of+research+participants:+assumptions,+ethics+and+practicalities.">The anonymity of research participants: assumptions, ethics and practicalities.</a> Social Research Update. 36 (1), 4 (2002).</li></ol>

The mEETr device and accompanied software have been developed in cooperation with a commercial partner; Noldus Information technology. The authors declare no conflicts of interest.

A healthy diet and a healthy eating behavior have shown to play a key role in the prevention of and solution to overweight and obesity11. However, many of the methods used to measure the dietary intake and the eating behavior are burdensome for users, researchers, and health-care professionals and may be biased as they are dependent on memory and portion size estimations. Using the mEETr, independently or alongside conventional video and dietary assessment methods, would decrease the effort and th...

An erratum was issued for:&#160;<a href="https://www.jove.com/t/62144">Concept Development and Use of an Automated Food Intake and Eating Behavior Assessment Method</a>. An author name was updated.
The name was updated from:
Cees de Graaf
to:
Kees de Graaf

An erratum was issued for:&#160;<a href="https://www.jove.com/t/62144">Concept Development and Use of an Automated Food Intake and Eating Behavior Assessment Method</a>. An author name was updated.

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

In nutrition research and dietary practice, it is key to have good measures of what, how much, and how people eat, to find solutions to the overweight and obesity problems. To assess dietary intake, often conventional self-report questionnaires are used such as food diaries, 24 h recalls or food frequency questionnaires1. These methods rely on self-report and are therefore time-consuming and prone to bias due to social-desirable answers, memory inadequacy, and difficulties in estimating portion sizes2,3. In addition to measures of the diet quality (food type and amount eaten), it is also important to know how the food is eaten, as eating behaviors that slow down food intake have been shown to prevent overconsumption within a meal4. To assess eating behavior the golden standard is to have two observers annotate video recordings of people eating a meal5. This method is rather labor intensive and time consuming and does not allow for immediate feedback on the behavior.
Recent technological advances now provide the opportunity to combine automated measures of food intake with automated measures of the eating behavior over the course of a meal. In response to these developments, a new sensor-based dietary assessment method was developed, called the mEETr, the acronym of the two Dutch words &#39;Meter&#39; (translated: measuring device), and &#39;eet&#39; (translated: to eat). The mEETr is a regular dining tray with three built-in weighing stations (Figure 1 demonstrates the design of the tray and the sensor plates) and a camera holder. Each weighing station consists of three triangularly positioned measurement points to distribute the weight. The weighing stations measure the weight of the bowl, plate, and drinking cup or glass continuously over the meal. The mEETr also includes a video-camera holder. Currently, the camera holder is separate from the tray, but for standardization purposes an integrated camera after the next upgrade of mEETr (a folding video camera stick) would be ideal. The camera facilitates automated real-time analysis of the number of bites and chews, and eating duration, which allows for the generation of information on the eating rate and the bite size. Automated analysis of eating behavior is done with the use of a newly developed algorithm. Various research groups have developed devices to provide people real-time feedback on the acceleration of eating and the quantity people eat6. Also, augmented forks have been developed to provide real-time feedback on the number of bites and their frequency within a meal7. Additionally, an ear sensor was developed to measure the microstructure of eating in free living conditions8,9. Similar to this device is the set-up used by Ioakimidis et al.10, where video measures were combined with a weighing plate to determine the food intake, number of bites, and chewing behavior.
Compared to these devices the novelty of the mEETr is that it combines automated measures of food intake of two plates and a drinking cup (n = 3) and eating behavior (e.g., eating rate, number of bites, bite size, and chewing behavior) in one device. The mEETr, as demonstrated, is suited for within meal measures of food intake and eating behavior within a controlled (eating lab) environment, but eventually the aim is to use the mEETr in less controlled environments where re-occurring meal plans are used such as daycares, elderly-homes, and hospitals.
Ultimately, the mEETr will provide a more objective, and as such, more accurate and precise measure of food intake and eating behavior than conventional dietary assessment methods and manual coding of videos. Better measures of the food intake would benefit nutrition and health research, but also the health professionals in their challenge to combat the increase in food-related non-communicable diseases11. Ultimately the mEETr can be used in research and health-care settings as well as by health-conscious users at home by linking the mEETr to existing technologies and software, such as other health apps or smart watches. Overall, these health measures provide the user or the health-care professional with a rather diverse and complete overview of a variety of health-behavior patterns (e.g., food intake, eating behavior, energy expenditure based on real-life measures, sleep, stress) enabling the user to optimize their diet and create a healthy lifestyle.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Battery</td>
			<td>na</td>
			<td>na</td>
			<td>Battery pack (LiPo) and charge electronics via an USB port connector. No data from this port.</td>
		</tr>
		<tr>
			<td>Connector program</td>
			<td>Noldus</td>
			<td></td>
			<td>Noldus Information technology software dashboard nview</td>
		</tr>
		<tr>
			<td>Dinner tray</td>
			<td>na</td>
			<td>na</td>
			<td>Standard dinner tray from glass inforced epoxy</td>
		</tr>
		<tr>
			<td>Larger scale</td>
			<td>na</td>
			<td>na</td>
			<td>One high range custom made scale based on a triple force sensor method.</td>
		</tr>
		<tr>
			<td>Mainboard</td>
			<td>na</td>
			<td>na</td>
			<td>A mainboard converting the three scale measurements to calibrated weight numbers. This board also contains the low power short range RF transmitter.</td>
		</tr>
		<tr>
			<td>OS Windows</td>
			<td>Microsoft</td>
			<td></td>
			<td>windows 10 Pro 64 bit</td>
		</tr>
		<tr>
			<td>Processor program</td>
			<td>Noldus</td>
			<td></td>
			<td>Noldus Information technology software FaceReader</td>
		</tr>
		<tr>
			<td>Receiver program</td>
			<td>Noldus</td>
			<td></td>
			<td>Noldus Information technology software Observer</td>
		</tr>
		<tr>
			<td>RF receiver</td>
			<td>na</td>
			<td>na</td>
			<td>Custom build USB converter connected to a RF receiver. This receiver has a squelch setting for making it low range sensitive.</td>
		</tr>
		<tr>
			<td>Small scales</td>
			<td>na</td>
			<td>na</td>
			<td>Two low range custom made scales based on a triple force sensor method.</td>
		</tr>
	</tbody>
</table>

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.

A slower ingestion rate (Figure 7), smaller sip/bite sizes (Figure 8), and more chews (Figure 9) led to lower intake of the salad compared to the yoghurt and juice (Figure 6) as measured by the mEETr tray. The participants ate 17% less of the fruit salad compared to the fruit juice. All the eating behavior characteristics differed between the juice, yoghurt, and salad (Figure 7</str...

Watch this Scientific Journal Video about Concept Development and Use of an Automated Food Intake and Eating Behavior Assessment Method at JoVE.com

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

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. ...

concept-development-use-an-automated-food-intake-eating-behavior

Research

Education

JoVE Core

JoVE Journal

Nursing

Behavior

Unit 1

Introduction to Health

SCIENTISTS IN ACTION

5.6K Views.  Wageningen University & Research. 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.

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

Studying Food Reward and Motivation in Humans

A key challenge in studying reward processing in humans is to go beyond subjective self-report measures and quantify different aspects of reward such as hedonics, motivation, and goal value in more objective ways. This is particularly relevant for the understanding of overeating and obesity as well as their potential treatments. In this paper are described a set of measures of food-related motivation using handgrip force as a motivational measure. These methods can be used to examine changes in food related motivation with metabolic (satiety) and pharmacological manipulations and can be used to evaluate interventions targeted at overeating and obesity. However to understand food-related decision making in the complex food environment it is essential to be able to ascertain the reward goal values that guide the decisions and behavioral choices that people make. These values are hidden but it is possible to ascertain them more objectively using metrics such as the willingness to pay and a method for this is described. Both these sets of methods provide quantitative measures of motivation and goal value that can be compared within and between individuals.

This article describes a set of methods for the measurement of food related motivation and food related goal values in humans.

A key challenge in studying reward processing in humans is to go beyond subjective self-report measures and quantify different aspects of reward such as ...

Assessment of Murine Exercise Endurance Without the Use of a Shock Grid: An Alternative to Forced Exercise

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most common method for assessing exercise endurance in mice utilizes forced running on a motorized treadmill equipped with a shock grid. Animals who quit running are pushed by the moving treadmill belt onto a grid that delivers an electric foot shock; to escape the negative stimulus, the mice return to running on the belt. However, avoidance behavior and psychological stress due to use of a shock apparatus can interfere with quantitation of running endurance, as well as confound measurements of postexercise serum hormone and cytokine levels. Here, we demonstrate and validate a refined method to measure running endurance in na&#239;ve C57BL/6 laboratory mice on a motorized treadmill without utilizing a shock grid. When mice are preacclimated to the treadmill, they run voluntarily with gait speeds specific to each mouse. Use of the shock grid is replaced by gentle encouragement by a human operator using a tongue depressor, coupled with sensitivity to the voluntary willingness to run on the part of the mouse. Clear endpoints for quantifying running time-to-exhaustion for each mouse are defined and reflected in behavioral signs of exhaustion such as splayed posture and labored breathing. This method is a humane refinement which also decreases the confounding effects of stress on experimental parameters.

A method to assess exercise endurance in laboratory mice without the use of a shock grid is demonstrated. This method is a humane refinement that can decrease the confounding effects of stress on experimental parameters.

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most ...

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 ...

Protocol for Data Collection and Analysis Applied to Automated Facial Expression Analysis Technology and Temporal Analysis for Sensory Evaluation

We demonstrate a method for capturing emotional response to beverages and liquefied foods in a sensory evaluation laboratory using automated facial expression analysis (AFEA) software. Additionally, we demonstrate a method for extracting relevant emotional data output and plotting the emotional response of a population over a specified time frame. By time pairing each participant's treatment response to a control stimulus (baseline), the overall emotional response over time and across multiple participants can be quantified. AFEA is a prospective analytical tool for assessing unbiased response to food and beverages. At present, most research has mainly focused on beverages. Methodologies and analyses have not yet been standardized for the application of AFEA to beverages and foods; however, a consistent standard methodology is needed. Optimizing video capture procedures and resulting video quality aids in a successful collection of emotional response to foods. Furthermore, the methodology of data analysis is novel for extracting the pertinent data relevant to the emotional response. The combinations of video capture optimization and data analysis will aid in standardizing the protocol for automated facial expression analysis and interpretation of emotional response data.

A protocol for capturing and statistically analyzing emotional response of a population to beverages and liquefied foods in a sensory evaluation laboratory using automated facial expression analysis software is described.

We demonstrate a method for capturing emotional response to beverages and liquefied foods in a sensory evaluation laboratory using automated facial ...

Feeding Experimentation Device (FED): Construction and Validation of an Open-source Device for Measuring Food Intake in Rodents

Food intake measurements are essential for many research studies. Here, we provide a detailed description of a novel solution for measuring food intake in mice: the Feeding Experimentation Device (FED). FED is an open-source system that was designed to facilitate flexibility in food intake studies. Due to its compact and battery powered design, FED can be placed within standard home cages or other experimental equipment. Food intake measurements can also be synchronized with other equipment in real-time via FED's transistor-transistor logic (TTL) digital output, or in post-acquisition processing as FED timestamps every event with a real-time clock. When in use, a food pellet sits within FED's food well where it is monitored via an infrared beam. When the pellet is removed by the mouse, FED logs the timestamp onto its internal secure digital (SD) card and dispenses another pellet. FED can run for up to 5 days before it is necessary to charge the battery and refill the pellet hopper, minimizing human interference in data collection. Assembly of FED requires minimal engineering background, and off-the-shelf materials and electronics were prioritized in its construction. We also provide scripts for analysis of food intake and meal patterns. Finally, FED is open-source and all design and construction files are online, to facilitate modifications and improvements by other researchers.

Feeding Experimentation Device FED: Construction and Validation of an Open-source Device for Measuring Food Intake in Rodents

Feeding Experimentation Device (FED) is an open-source device for measuring food intake in mice. FED can also synchronize food intake measurements with other techniques via a real-time digital output. Here, we provide a step-by-step tutorial for the construction, validation, and usage of FED.

Food intake measurements are essential for many research studies. Here, we provide a detailed description of a novel solution for measuring food intake in ...

Combining Quantitative Food-intake Assays and Forcibly Activating Neurons to Study Appetite in Drosophila

Food consumption is under the tight control of the brain, which integrates the physiological status, palatability, and nutritional contents of the food, and issues commands to start or stop feeding. Deciphering the processes underlying the decision-making of timely and moderate feeding carries major implications in our understanding of physiological and psychological disorders related to feeding control. Simple, quantitative, and robust methods are required to measure the food ingestion of animals after experimental manipulation, such as forcibly increasing the activities of certain target neurons. Here, we introduced dye-labeling-based feeding assays to facilitate the neurogenetic study of feeding control in adult fruit flies. We review available feeding assays, and then describe our methods step-by-step from setup to analysis, which combine thermogenetic and optogenetic manipulation of neurons controlling feeding motivation with dye-labeled food intake assay. We also discuss the advantages and limitations of our methods, compared with other feeding assays, to help readers choose an appropriate assay.

Combining Quantitative Food-intake Assays and Forcibly Activating Neurons to Study Appetite in Drosophila

Quantitative food-intake assays with dyed food provide a robust and high-throughput means to evaluate feeding motivation. Combining the food consumption assay with thermogenetic and optogenetic screens is a powerful approach to investigate the neural circuits underlying appetite in adult Drosophila melanogaster.

Food consumption is under the tight control of the brain, which integrates the physiological status, palatability, and nutritional contents of the food, ...

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 ...

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.

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 ...

An Assessment Method and Toolkit to Evaluate Keyboard Design on Smartphones

Keyboard input has played an essential role in human-computer interaction with a vast user base, and the keyboard design has always been one of the fundamental objects of studies on smart devices. With the development of screen technology, more precise data and indicators could be collected by smartphones to in-depth evaluate the keyboard design. The enlargement of the phone screen has led to unsatisfactory input experience and finger pain, especially for one-handed input. The input efficiency and comfort have attracted the attention of researchers and designers, and the curved keyboard with size-adjustable buttons, which roughly accorded with the physiological structure of thumbs, was proposed to optimize the one-handed usage on large-screen smartphones. However, its real effects remained ambiguous. Therefore, this protocol demonstrated a general and summarized method to evaluate the effect of curved QWERTY keyboard design on a 5-inch smartphone through a self-developed software with detailed variables, including objective behavioral data, subjective feedback, and the coordinate data of each touchpoint. There is sufficient existing literature on evaluating virtual keyboards; however, only a few of them systematically summarized and took reflection on the evaluation methods and processes. Therefore, this protocol fills in the gap and presents a process and method of the systematic evaluation of keyboard design with available codes for analysis and visualization.&#160;It needs no additional or expensive equipment&#160;and is easy to conduct and operate. In addition, the protocol also helps to get potential reasons for the disadvantages of the design and enlightens the optimization of designs. In conclusion, this protocol with the open-source resources could not only be an in-class demonstrative experiment to inspire the novice to start their studies but also contributes to improving the user experience and the revenue of input method editor companies.

The presented protocol integrates various evaluation methods and demonstrates a method to evaluate the keyboard design on smartphones. Pairs matched by English characters are proposed as the input material, and the transition time between two keys is used as the dependent variable.

Keyboard input has played an essential role in human-computer interaction with a vast user base, and the keyboard design has always been one of the ...