This study was sponsored by the National Natural Science Foundation of China (81772423), the K. C. Wong Magna Fund of Ningbo University, and the National Social Science Foundation of China (16BTY085).

The experiment was approved by the Ethics Committee of the Faculty of Sports Science in Ningbo University. All the participants have signed written consents and were told about the requirements and process of the lunge experiment.
1. Gait Laboratory Preparation
<ol>
	<li>When calibrating, remove or cover other potentially reflective items in the volume, avoid the effects of reflections from sunlight, light, and other reflective items on the identification, and ensure a reasonable fluorescent light in the laboratory.</li>
	<li>Plug the dongle into the PC and turn on the motion capture cameras, proprietary tracking software, force platform amplifiers, and the external analog-to-digital converter (ADC).</li>
	<li>Place eight cameras on both sides of the simulated badminton court. Initialize the cameras. Select the Local System node from the System resources pane, and each of the camera nodes will display a green light if selected correctly.
	<ol>
		<li>In the Camera view pane, click Properties to adjust the camera parameters: set the Strobe Intensity to 0.95 to 1, the Threshold to 0.2 - 0.4, the Gain to times 1 (x1), the Grayscale mode to Auto, the Minimum circularity ratio to 0.5, the Max blob height to 50, and select Enable LEDs.</li>
	</ol>
	</li>
	<li>Select Camera in the Perspective pane and put the T-frame on the force plate. In the System resources pane, click the MX Cameras, and select multiple cameras to adjust the parameters.
	<ol>
		<li>In the Setting section, set the parameters of all selected cameras to ensure that data transmitted from each camera can be seen.</li>
	</ol>
	</li>
	<li>Select the 5 marker wand &#38; T-frame in the drop-down menu of the T-frame and select all the cameras.</li>
	<li>Click the split screen button in the upper right corner of the Properties pane. Select the Camera Positions in the Option panel and click the Off button in the drop-down menu of the Extended Frustum.
	<ol>
		<li>Wave the T-frame around the capture volume and stop until the blue light of the camera stops flashing.</li>
	</ol>
	</li>
	<li>Start the calibration, which means the camera continuously collects the data of the markers and displays the collected valid data in the MX Cameras Calibration Feedback toolbar below the Tools pane. Finish the calibration; the progress bar returns to 0%. Ensure the value displayed in the Image Error is less than 0.3.</li>
	<li>Put the T-frame on the force plate (60 x 90 cm) with the axis along the edge of the plate. Ensure that the direction of the T-frame is in accordance with the experimental direction.</li>
	<li>Ensure that the origin of the T-frame is also that of capture volume. Click the Start button from the Set volume origin in the Tool pane to set the origin.</li>
	<li>Ask the subjects to stand on the force plate. Confirm that the direction of the ground reaction vector is upward. Ask the subjects step off the force plate.</li>
	<li>Before starting the trials, click the Force, and select Zero Level. Find the valid data collected in the Wand Count and ensure that each camera collects at least 1,000 frames of valid data.</li>
	<li>Prepare 16 markers of 14 mm in diameter and paste double-sided tape on them in advance.</li>
</ol>
2. Subject Preparation
<ol>
	<li>Let potential subjects fill in a questionnaire survey. Obtain written informed consent from the subjects that fulfill the inclusion criteria. 
	NOTE: Questions: (i) How many years have you played badminton? (ii) Have you participated in professional national level badminton competitions? (iii) Have you suffered any sports injuries and received surgeries? Here, a total of 16 male participants took part in the study: eight professional badminton players and eight amateur badminton players.</li>
	<li>Determine of the subjects meet the criteria. 
	&#8203;NOTE: The criteria include the following items. All participants did not suffer from any injuries in the upper and lower limbs in the six months before the study; the subjects also did not take part in any high-intensity training or competition 2 d before the experiment; for all subjects, the right hand and leg were dominant. Half of the subjects were professional players, half were amateur players; this resulted in eight subjects who are professional badminton players (ages: 23.4 &#177; 1.3 years; height: 172.7 &#177; 3.8 cm; mass: 66.3 &#177; 3.9 kg; badminton-playing years: 9.7 &#177; 1.2 years) and have participated in professional national level competitions, and eight subjects who are amateur badminton players (ages: 22.5 &#177; 1.4 years; height: 173.2 &#177; 1.8 cm; mass: 67.5 &#177; 2.3 kg; badminton playing years: 3.2 &#177; 1.1 years).</li>
	<li>Ask the subjects to wear T-shirts and tight shorts.</li>
	<li>Measure the subjects&#39; height (mm) and weight (kg), as well as the length of both left and right leg (mm) from the superior iliac spine to the ankle internal condyle, the knee widths (mm) from the medial to the lateral knee condyle, and the ankle widths (mm) from the medial to the lateral ankle condyle.</li>
	<li>Mark the skin areas of the anatomical bony landmarks to place the makers.
	<ol>
		<li>Shave body hair as needed and wipe the skin with alcohol. 
		NOTE: The marker locations include spaces bilaterally located to the anterior-superior iliac spine, posterior-superior iliac spine (PSI), lateral thigh (THI), lateral knee (KNE), lateral tibia (TIB), lateral ankle (ANK), heel (HEE), and toe (TOE).</li>
	</ol>
	</li>
	<li>Palpateto identify the anatomical landmarks. Paste the 16 markers on the lower limb.</li>
	<li>Ask the subjects to wear the same brand and series of badminton shoes; then, let them perform a right forward lunge naturally, and ensure the markers on their lower limbs are captured by the cameras.</li>
	<li>Ask the subjects to perform the right forward lunge at a comfortable low speed in the simulated court until they can perform the movement steadily, and instruct them to perform some auxiliary exercises (e.g., marching lunge leg stretch) to warm up.</li>
	<li>Ask the subjects to perform the right forward lunge at a comfortable high speed in the simulated court until they can perform the movement steadily at this speed; then, ask them to put their right leg in the designated area (position B in Figure 1) and underhand strike the shuttlecock to the backcourt (position C).</li>
	<li>Instruct the subjects to perform a maximal right forward lunge from start position A (Figure 1) and underhand strike the shuttlecock to the backcourt (position C), ensuring that their right leg naturally steps on and fully contacts the force platform as they pass, and the subjects must go back to start position A after striking the shuttlecock.</li>
</ol>
3. Static Calibration
<ol>
	<li>Open the Data Management to create a new database. Select the Location, type in the name, and select Based on | Clinical template; then, click on Create.</li>
	<li>Select the subject&#39;s name and click on Open. Click on New patient classification | New patient | New session in order to create the subjects&#39; information.</li>
	<li>At the beginning of the trials, select Session to capture data. Return to the Nexus pane, click on Subjects, and then, click the New subject button. Rename the trials if necessary.</li>
	<li>Click on Go Live, select Split horizontally, and select Graph to view the Trajectory Count.
	<ol>
		<li>Check the number of the markers, which is 16, indicating that there is no unwanted light pollution and all the markers have been captured.</li>
	</ol>
	</li>
	<li>Start to capture static data. In the Subject Preparation section of the toolbar, select Subject Capture and click the Start button. Ask the subjects to stay still and capture 200 frames of images. Click the Stop button.</li>
	<li>Click on Run the reconstruct pipeline to construct markers data. Select Label, identify in the markers&#39; list, and apply the labels to the corresponding markers. Click the Save button. Press the Esc key to exit.</li>
	<li>Click the Subject Preparation and select the Static plug-in gait in the Subject calibration drop-down menu.</li>
	<li>Click Option in the Frame range window that is newly displayed and select Left foot and Right foot in the pop-up window. Select the Start button and, then, save.</li>
</ol>
4. Dynamic Trials
<ol>
	<li>Ask the subject to be in the proper start position.</li>
	<li>After creating the static template, click the Go Live button and select the Capture. Set the Trial Type and the Session in order. Type in a trial name, and the Description is optional.</li>
	<li>Click the Start button in the last option to start capturing and stop after finishing the process. Just repeat the process for each trial.
	<ol>
		<li>In order to conduct experiments, ask the subjects to perform the lunge fast and naturally. Ensure there is a 2 min interval between each trial.</li>
		<li>Ask the subjects the perform the right forward lunge, of which the last step is on the force plate. Require the subjects to perform the movement 6x. If the markers shift or drop, reattach them promptly and capture again.</li>
	</ol>
	</li>
	<li>Select Stop after the subjects perform a maximal right forward lunge and go back to position A (start/finish position).</li>
</ol>
5. Postprocessing
<ol>
	<li>Use special software for postprocessing. Open Data management, double-click the x icon under Files, and click the Run the reconstruct pipeline and labels button; then, click Play under the Perspective pane to play the captured video.</li>
	<li>Drag the pointers on the progress bar under the Perspective pane to set the start and end time of the video.</li>
	<li>Place the cursor within the progress bar, and right-click to select Zoom to Region-of-Interest.</li>
	<li>The identification step is the same as the static identification process. Check the markers and click Fill. Check if all the markers are identified by observing their trajectories. Right-click on unlabeled markers and select Delete all unlabeled.</li>
	<li>Click Start, and the files will be exported in .csv format for postprocessing.</li>
</ol>
6. Data Analysis
<ol>
	<li>Filter kinematic and kinetic data using low-pass Butterworth filters with frequencies at 10 Hz and 25 Hz.</li>
	<li>Calculate the ROMs of the knee and the ankle on sagittal, frontal, and horizontal planes, and obtain the knee and ankle moments through the approach of three-dimensional inverse dynamics. 
	NOTE: The ROMs of the ankle and knee were obtained from the maximum and minimum joint angles on three-dimensional movement planes.</li>
	<li>Divide the lunge into four phases, which include the initial impact peak (I, 5% of the stance), the secondary impact peak (II, 20% of the stance), weight acceptance (III, 40% - 70% of the stance), and the drive-off (IV, 80% of the stance).</li>
	<li>Standardize all joint moment data by using the subjects&#39; weights.</li>
	<li>Collect ground reaction forces and kinematic data at the same time. For each subject, use the mean values of the kinematic and kinetic data of six successful trials for statistical analysis. 
	NOTE: The parameters include the joint (i.e., ankle, knee, and hip) three-dimensional ROMs and the knee and ankle moments.</li>
	<li>Transmit the data to the software for analysis.</li>
</ol>
7. Statistical Analysis
<ol>
	<li>Examine the data of the captured ankle and knee ROMs and the joint moments, using independent-sampled t-tests between the professional players and the amateur players. Use a two-sample t-test to calculate the appropriate number of subjects. Indicate the joints&#39; ROMs and moments by mean values. Set the significance level at p = 0.05.</li>
</ol>

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The authors have nothing to disclose.

One of the disadvantages of most studies analyzing the biomechanical characteristics of the badminton lunging step is that they ignore the skill level of the badminton players performing the lunge. This study divides the subjects into professional players and amateur players to explore the differences in joint ROM and joint moment at different levels when performing a right forward lunge.
As for the ankle joint ROM on the frontal plane, the amateur players exhibited greater ROM than the profes...

Badminton has always been one of the most popular sports in the world. In a game, the frequency of performing lunges is relatively high1. It is of vital importance to master the ability to quickly perform a lunge and return to the start position or move in the other direction2. The lunge not only is crucial to badminton but also is of great importance to tennis, table tennis, and other sports.
The forward lunge has been taken as a function evaluation method for anterior cruciate ligament (ACL) deficiency and knee stability3,4. Studies show that badminton players need both high muscular strength and professional techniques. In general, amateur players pay more attention to technical training than to muscular strength training. If an individual of low-strength ability takes a low-quality training, the training time becomes longer, therefore leading to an overload of the lower limbs and even to a sports injury.
High-intensity training results in a large load on the lower limbs, which may be the cause of sports injuries5. Lower limb injuries account for 60% of the total number of injuries. For both male and female badminton players, the knee and the foot are the most vulnerable parts6,7,8,9. Kinetic data analysis can be used to explain the lower limb injuries of players at different levels. It was reported that professional badminton players have considerable intratendinous flow which rises after repetitive load movements, especially in the patella tendon of the dominant leg.
Reports show that previously conducted research on racquet sports mainly assessed kinematic parameters but focused less on kinetics2,10. When a professional player has played a competition, the pressure is concentrated in their Achilles tendon and anterior knee tendons, especially in the dominant lunge leg5. In racquet sports, clinical analyses of injuries mainly focused on the lower limb, which exceeded 58%, specifically on the knee and ankle5,8,10,11,12,13.
Previous studies have evaluated the physiological indicators of badminton14,15,16 and the features of physical abilities17,18,19,20. Due to these basic features, basic actions on the agility of badminton are proposed to improve the training effect and the on-the-spot performance of the players21,22. Previous studies on badminton focused on different movements or directions of lunge movement without comparing the movement characteristics between professional and amateur badminton players23,24,25,26,27. These differences in dynamics and joint movement make them susceptible to different mechanisms of sports injuries.
The aim of this study is to study the differences in kinematics and dynamics between professional badminton players and amateur badminton players, as well as the range of movement (ROM) of the dominant leg. It is assumed that professional and amateur badminton players show differences in the right forward lunge and that a greater ROM increases the risk of sports injuries.

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			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
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			<td style="width:167px;">n= 8</td>
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			<td height="21" style="height:21px;width:216px;">Valid Dongle</td>
			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
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			<td>Vicon Nexus 1.4.116</td>
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			<td style="width:71px;">Kistler, Switzerland</td>
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			<td>n=1</td>
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			<td style="width:71px;">Kistler, Switzerland</td>
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			<td>n=1</td>
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			<td height="22" style="height:23px;">Vicon Datastation ADC&#160;</td>
			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:119px;"></td>
			<td>-</td>
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			<td height="22" style="height:22px;width:216px;">T-Frame</td>
			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:119px;">-</td>
			<td>-</td>
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			<td height="22" style="height:23px;width:216px;">14 mm Diameter Passive Retro-reflective Marker</td>
			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:119px;"></td>
			<td>n=16</td>
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			<td height="22" style="height:22px;width:216px;">Double Adhesive Tape</td>
			<td style="width:71px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:119px;"></td>
			<td>For fixing markers to skin</td>
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			<td height="210" style="height:210px;width:216px;">Badmionton racket&#160;</td>
			<td>Li-ning, China</td>
			<td style="width:119px;">BADMINTON RACKET CLUB PLAY BLADE 1000 
			[AYPL186-4]</td>
			<td style="width:167px;">MATERIAL: Standard Grade Carbon Fiber 
			WEIGHT: 81-84 grams 
			OVERALL LENGTH: 675mm 
			GRIP LENGTH: 200mm 
			BALANCE POINT: 295mm 
			TENSION: Vertical 20-24 lbs, Horizontal 22-26 lbs</td>
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biomechanical analysis methods to assess professional badminton players' lunge performance

Under the condition of simulating a badminton court in the laboratory, this study used the injury mechanism model to analyze the maximal right lunge movements of eight professional badminton players and eight amateur players. The purpose of this protocol is to study the differences in kinematics and joint moment of the right knee and ankle. A motion capture system and force plate were used to capture data of the joint movements of the lower extremity and the vertical ground reaction force (vGRF). Sixteen young men who did not have any sports injuries in the past 6 months took part in the study. The subjects performed a maximal right lunge from the start position with their right foot, stepping on and fully contacting with the force plate, hit the shuttlecock with an underhand stroke to the designated position in the backcourt, and then returned to the start/end position. All subjects wore the same badminton shoes to avoid a difference in impact from different badminton shoes. The amateur players showed a greater range of ankle movement and reverse joint moment on the frontal plane, and a larger internal joint rotation moment on the horizontal plane. The professional badminton players exhibited greater knee moment on the sagittal and frontal planes. Therefore, these factors should be considered in the development of the training program to reduce the risk of sports injuries in knee and ankle joints. This study simulates the real badminton court and calibrates the range of activities of each movement of the subjects so that the subjects complete the experimental action in a natural state with high quality. A limitation of this study is that it does not combine joint load and muscle activity. Another limitation is that the sample size is small and should be expanded in future studies. This research method can be applied to the lower limb biomechanical research of other footwork in the badminton project.

Figure 2&#160;shows the mean vGRF of phases I, II, III, and IV (i.e., the initial impact peak, secondary impact peak, weight acceptance, and drive-off phases, respectively) of the professional players and the amateur players when they performed a lunge. There is no significant difference in phases I, II, and III. However, the vGRF of the professional players is markedly higher than that of the amateur players, indicating a significant difference (<st...

Watch this Scientific Journal Video about Biomechanical Analysis Methods to Assess Professional Badminton Players' Lunge Performance at JoVE.com

Biomechanical Analysis Methods to Assess Professional Badminton Players' Lunge Performance

Here, we present a protocol to evaluate the differences in injury mechanisms between professional and amateur players when performing a badminton maximal right lunge movement by analyzing lower limb kinematics.

Under the condition of simulating a badminton court in the laboratory, this study used the injury mechanism model to analyze the maximal right lunge ...

biomechanical-analysis-methods-to-assess-professional-badminton

Research

JoVE Journal

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10.5K Views.  Ningbo University. Here, we present a protocol to evaluate the differences in injury mechanisms between professional and amateur players when performing a badminton maximal right lunge movement by analyzing lower limb kinematics.

Video: Biomechanical Analysis Methods to Assess Professional Badminton Players' Lunge Performance

Methods to Test Visual Attention Online

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative data samples than can typically be collected on college campuses. However, before such methods can be widely adopted, a number of technological challenges must be overcome &#8211; in particular in experiments where tight control over stimulus properties is necessary. Here we present methods for collecting performance data on two tests of visual attention. Both tests require control over the visual angle of the stimuli (which in turn requires knowledge of the viewing distance, monitor size, screen resolution, etc.) and the timing of the stimuli (as the tests involve either briefly flashed stimuli or stimuli that move at specific rates). Data collected on these tests from over 1,700 online participants were consistent with data collected in laboratory-based versions of the exact same tests. These results suggest that with proper care, timing/stimulus size dependent tasks can be deployed in web-based settings.

To replicate laboratory settings, online data collection methods for visual tasks require tight control over stimulus presentation. We outline methods for the use of a web application to collect performance data on two tests of visual attention.

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative ...

Multifunctional Setup for Studying Human Motor Control Using Transcranial Magnetic Stimulation, Electromyography, Motion Capture, and Virtual Reality

The study of neuromuscular control of movement in humans is accomplished with numerous technologies. Non-invasive methods for investigating neuromuscular function include transcranial magnetic stimulation, electromyography, and three-dimensional motion capture. The advent of readily available and cost-effective virtual reality solutions has expanded the capabilities of researchers in recreating &#8220;real-world&#8221; environments and movements in a laboratory setting. Naturalistic movement analysis will not only garner a greater understanding of motor control in healthy individuals, but also permit the design of experiments and rehabilitation strategies that target specific motor impairments (e.g. stroke). The combined use of these tools will lead to increasingly deeper understanding of neural mechanisms of motor control. A key requirement when combining these data acquisition systems is fine temporal correspondence between the various data streams. This protocol describes a multifunctional system&#8217;s overall connectivity, intersystem signaling, and the temporal synchronization of recorded data. Synchronization of the component systems is primarily accomplished through the use of a customizable circuit, readily made with off the shelf components and minimal electronics assembly skills.

Transcranial magnetic stimulation, electromyography, and 3D motion capture are commonly used non-invasive techniques for investigating neuromuscular function in humans. In this paper, we describe a protocol that synchronously samples data generated by all three of these tools along with the unique addition of virtual reality stimulus presentation and feedback.

The study of neuromuscular control of movement in humans is accomplished with numerous technologies. Non-invasive methods for investigating neuromuscular ...

Use of Galvanic Skin Responses, Salivary Biomarkers, and Self-reports to Assess Undergraduate Student Performance During a Laboratory Exam Activity

Typically, self-reports are used in educational research to assess student response and performance to a classroom activity. Yet, addition of biological and physiological measures such as salivary biomarkers and galvanic skin responses are rarely included, limiting the wealth of information that can be obtained to better understand student performance. A laboratory protocol to study undergraduate students&#39; responses to classroom events (e.g., exams) is presented. Participants were asked to complete a representative exam for their degree. Before and after the laboratory exam session, students completed an academic achievement emotions self-report and an interview that paralleled these questions when participants wore a galvanic skin sensor and salivary biomarkers were collected. Data collected from the three methods resulted in greater depth of information about students&#39; performance when compared to the self-report. The work can expand educational research capabilities through more comprehensive methods for obtaining nearer to real-time student responses to an examination activity.

Research on undergraduate students' academic achievement emotions have primarily relied on self-reports in laboratory settings. Studies rarely include bio-physiological measures to these self-reports. This protocol will describe a methodology that integrates self-reports with and bio-physiological measures to assess student response and performance during a laboratory examination activity.

Typically, self-reports are used in educational research to assess student response and performance to a classroom activity. Yet, addition of biological ...

The Emotional Stroop Task: Assessing Cognitive Performance under Exposure to Emotional Content

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than to ink colors of neutral words. The difference shows that people are affected by the emotional content conveyed by the carrier words even though they are irrelevant to the color-naming task at hand. The ESE has been widely deployed with patient populations, as well as with non-selected populations, because the emotion words can be selected to match the tested pathology. The ESE is a powerful tool, yet it is vulnerable to various threats to its validity. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them. The most prevalent threat to the validity of existing ESE studies is sustained effects and habituation wrought about by repeated exposure to emotion stimuli. Consequently, the order of exposure to emotion and neutral stimuli is of utmost importance. We show that in the standard design, only one specific order produces the ESE.

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than those of neutral words. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them.

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than to ink colors of neutral words. The ...

Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication

Mice emit ultrasonic vocalizations in different contexts throughout development and in adulthood. These vocal signals are now currently used as proxies for modeling the genetic bases of vocal communication deficits. Characterizing the vocal behavior of mouse models carrying mutations in genes associated with neuropsychiatric disorders such as autism spectrum disorders will help to understand the mechanisms leading to social communication deficits. We provide here protocols to reliably elicit ultrasonic vocalizations in pups and in adult mice. This standardization will help reduce inter-study variability due to the experimental settings. Pup isolation calls are recorded throughout development from individual pups isolated from dam and littermates. In adulthood, vocalizations are recorded during same-sex interactions (without a sexual component) by exposing socially motivated males or females to an unknown same-sex conspecific. We also provide a protocol to record vocalizations from adult males exposed to an estrus female. In this context, there is a sexual component in the interaction. These protocols are established to elicit a large amount of ultrasonic vocalizations in laboratory mice. However, we point out the important inter-individual variability in the vocal behavior of mice, which should be taken into account by recording a minimal number of individuals (at least 12 in each condition). These recordings of ultrasonic vocalizations are used to evaluate the call rate, the vocal repertoire and the acoustic structure of the calls. Data are combined with the analysis of synchronous video recordings to provide a more complete view on social communication in mice. These protocols are used to characterize the vocal communication deficits in mice lacking ProSAP1/Shank2, a gene associated with autism spectrum disorders. More ultrasonic vocalizations recordings can also be found on the mouseTube database, developed to favor the exchange of such data.

Mouse ultrasonic vocalizations are used as proxies to model the genetic bases of vocal communication deficits in mouse models for neuropsychiatric disorders. The present protocol describes three experimental contexts that reliably elicit ultrasonic vocalizations from pups (throughout development) and adult mice (same-sex interactions, male-estrus female interactions).

Mice emit ultrasonic vocalizations in different contexts throughout development and in adulthood. These vocal signals are now currently used as proxies ...

Using Gold-standard Gait Analysis Methods to Assess Experience Effects on Lower-limb Mechanics During Moderate High-heeled Jogging and Running

A limited number of studies have explored lower-limb biomechanics during high-heeled jogging and running, and most studies have failed to clarify the wearing experience of subjects. This protocol describes the differences in lower-limb kinematics and ground reaction force (GRF) between experienced wearers (EW) and inexperienced wearers (IEW) during moderate high-heeled jogging and running. A three-dimensional (3D) motion analysis system with a configured force platform was used to synchronously capture lower-limb joint movements and GRF. 36 young females volunteered to participate in this study and were asked about high-heeled shoe-wearing experience, including frequency, duration, heel types, and heel heights. Eleven who had the experience of 3 to 6 cm heels for a minimum of three days per week (6 h per day) for at least two years and eleven who wore high heels less than twice per month participated. Subjects performed jogging and running at comfortable low and high speeds, respectively, with the right foot completely stepping onto a force platform when passing by along a 10 m walkway. EW and IEW adopted different biomechanical adaptations while jogging and running. IEW exhibited a generally larger range of joint movement, while EW showed a dramatically larger loading rate of GRF during running. Hence, further studies on the lower-limb biomechanics of high-heeled gait should strictly control the wearing experience of the subjects.

This study investigated lower-limb kinematics and ground reaction force (GRF) during moderate high-heeled jogging and running. Subjects were divided into groups of experienced wearers and inexperienced wearers. A three-dimensional motion analysis system with a configured force platform captured lower-limb joint movements and GRF.

A limited number of studies have explored lower-limb biomechanics during high-heeled jogging and running, and most studies have failed to clarify the ...

An Automated Method to Determine the Performance of Drosophila in Response to Temperature Changes in Space and Time

Temperature is a ubiquitous environmental factor that affects how species distribute and behave. Different species of Drosophila fruit flies have specific responses to changing temperatures according to their physiological tolerance and adaptability. Drosophila flies also possess a temperature sensing system that has become fundamental to understanding the neural basis of temperature processing in ectotherms. We present here a temperature-controlled arena that permits fast and precise temperature changes with temporal and spatial control to explore the response of individual flies to changing temperatures. Individual flies are placed in the arena and exposed to pre-programmed temperature challenges, such as uniform gradual increases in temperature to determine reaction norms or spatially distributed temperatures at the same time to determine preferences. Individuals are automatically tracked, allowing the quantification of speed or location preference. This method can be used to rapidly quantify the response over a large range of temperatures to determine temperature performance curves in Drosophila or other insects of similar size. In addition, it can be used for genetic studies to quantify temperature preferences and reactions of mutants or wild-type flies. This method can help uncover the basis of thermal speciation and adaptation, as well as the neural mechanisms behind temperature processing.

An Automated Method to Determine the Performance of Drosophila in Response to Temperature Changes in Space and Time

Here we present a protocol to automatically determine the locomotor performance of Drosophila at changing temperatures using a programmable temperature-controlled arena that produces fast and accurate temperature changes in time and space.

Temperature is a ubiquitous environmental factor that affects how species distribute and behave. Different species of Drosophila fruit flies have specific ...

Using Facial Electromyography to Assess Facial Muscle Reactions to Experienced and Observed Affective Touch in Humans

"Affective" touch is believed to be processed in a manner distinct from discriminatory touch and to involve activation of C-tactile (CT) afferent fibers. Touch that optimally activates CT fibers is consistently rated as hedonically pleasant. Patient groups with impaired social-emotional functioning also show disordered affective touch ratings. However, relying on self-reported ratings of touch has many limitations, including recall bias and communication barriers. Here, we describe a methodological approach to study affective responses to touch via facial electromyography (EMG) that circumvents the reliance on self-report ratings. Facial EMG is an objective, quantitative, and non-invasive method to measure facial muscle activity indicative of affective responses. Responses can be assessed across healthy and patient populations without the need for verbal communication. Here, we provide two separate datasets demonstrating that CT-optimal and non-optimal touch elicit distinct facial muscle reactions. Moreover, facial EMG responses are consistent across stimulus modalities, e.g. tactile (experienced touch) and visual (observed touch). Finally, the temporal resolution of facial EMG can detect responses on timescales that supersede that of verbal reporting. Together, our data suggest that facial EMG is a suitable methodology for use in affective tactile research that can be used to supplement, or in some cases, supplant, existing measures.

We describe a protocol to assess facial muscle activity in response to experienced and observed tactile stimulation using facial electromyography.

"Affective" touch is believed to be processed in a manner distinct from discriminatory touch and to involve activation of C-tactile (CT) afferent fibers. ...

Swimming Induced Paralysis to Assess Dopamine Signaling in Caenorhabditis elegans

The swimming assay described in this protocol is a valid tool to identify proteins regulating the dopaminergic synapses. Similar to mammals, dopamine (DA) controls several functions in C. elegans including learning and motor activity. Conditions that stimulate DA release (e.g., amphetamine (AMPH) treatments) or that prevent DA clearance (e.g., animals lacking the DA transporter (dat-1) which are incapable of reaccumulating DA into the neurons) generate an excess of extracellular DA ultimately resulting in inhibited locomotion. This behavior is particularly evident when animals swim in water. In fact, while wild-type animals continue to swim for an extended period, dat-1 null mutants and wild-type treated with AMPH or inhibitors of the DA transporter sink to the bottom of the well and do not move. This behavior is termed "Swimming Induced Paralysis" (SWIP). Although the SWIP assay is well established, a detailed description of the method is lacking. Here, we describe a step-by-step guide to perform SWIP. To perform the assay, late larval stage-4 animals are placed in a glass spot plate containing control sucrose solution with or without AMPH. Animals are scored for their swimming behavior either manually by visualization under a stereoscope or automatically by recording with a camera mounted on the stereoscope. Videos are then analyzed using a tracking software, which yields a visual representation of thrashing frequency and paralysis in the form of heat maps. Both the manual and automated systems guarantee an easily quantifiable readout of the animals' swimming ability and thus facilitate screening for animals bearing mutations within the dopaminergic system or for auxiliary genes. In addition, SWIP can be used to elucidate the mechanism of action of drugs of abuse such as AMPH.

Swimming Induced Paralysis to Assess Dopamine Signaling in Caenorhabditis elegans

Swimming induced paralysis (SWIP) is a well-established behavioral assay used to study the underlying mechanisms of dopamine signaling in Caenorhabditis elegans (C. elegans). However, a detailed method to perform the assay is lacking. Here, we describe a step-by-step protocol for SWIP.

The swimming assay described in this protocol is a valid tool to identify proteins regulating the dopaminergic synapses. Similar to mammals, dopamine (DA) ...

A Standardized Protocol for Preference Testing to Assess Fish Welfare

Animal welfare assessment techniques try to take into consideration the specific needs and wants of the animal in question. Providing enrichment (the addition of physical objects or conspecifics in the housing environment) is often a way to give captive animals the opportunity to choose who or what they interact with and how they spend their time. A fundamental component of the aquatic environment that is often overlooked in captivity, however, is the ability for the animal to choose to engage in physical exercise. For many animals, including fish, exercise is an important aspect of their life history, and is known to have many health benefits, including positive changes in the brain and behavior. Here we present a method for assessing habitat preferences in captive animals. The protocol could easily be adapted to look at a variety of environmental factors (e.g., gravel versus sand as a substrate, plastic plants versus live plants, low flow versus high flow of water) in different aquatic species, or for use with terrestrial species. Statistical assessment of preference is carried out using Jacob&#39;s preference index, which ranks the habitats from -1 (avoidance) to +1 (most preferred). With this information, it can be determined what the animal wants from a welfare perspective, including their preferred location.

A fundamental aspect of assessing the welfare of animals in captivity is to ask whether the animals have what they want. Here, we present a protocol to determine housing preference in the zebrafish (Danio rerio) with respect to the presence/absence of environmental enrichment and access to flowing of water.

Animal welfare assessment techniques try to take into consideration the specific needs and wants of the animal in question. Providing enrichment (the ...