This work was supported by the National Natural Science Foundation of China (No. 81772423). The authors would like to thank the table tennis players who participated in this study.

This study was approved by The Human Ethics Committee of Ningbo University, China. Written informed consent was obtained from all subjects after they were told about the goal, details, requirements, and experimental procedures of the table tennis experimental.
1. Laboratory preparation for table tennis
<ol>
	<li>Insert the USB dongle into the PC&#39;s parallel port and open the motion-capture infrared cameras and analog-to-digital converter. 
	NOTE: In this laboratory, the force platform (sampling frequency of 1000 Hz) is used together with the motion acquisition system, and the data collected by the force platform was displayed and preliminarily analyzed through the same system. The default sampling frequency of the force platform is 1000 Hz.</li>
	<li>Double-click the software icon on the desktop to open the tracking software. 
	NOTE: Before opening the software, remove all obstacles in the experimental environment and clean the ground.</li>
	<li>Every camera node will show a green light if the hardware connection is true. When the indicator light of all cameras is green, select eight cameras in the Local System.</li>
	<li>Click on Camera in the Perspective window and adjust the Strobe Intensity as 0.95-1, Gain to times 1 (x1), Threshold as 0.2-0.4, Minimum Circularity Ratio as 0.5, Grayscale Mode to Auto, as well as Max Blob Height to 50.</li>
	<li>Place the T correction rack in the center of the shooting area, and select eight cameras in the system. Using a 2D model, confirm that the camera can discern T correction and that there are no noise points.
	<ol>
		<li>Place the T correction rack in the center of the camera area. Click on the System Preparation, the L - Frame drop-down list, and select 5 Marker Wand &#38; L - Frame. Then, click on the Start button under the AimMX cameras option.</li>
	</ol>
	</li>
	<li>Select the System preparation button, and click on the Start button in the Calibrate MX Camera section in the Tool pane. Then, wave the T-wand in the capture range. When the blue light on the infrared camera stops flashing, stop the action.
	<ol>
		<li>Observe the progress bar until the calibration process is complete at 100% and returns to 0%. At the same time, observe the error of the image. When the error of the image is less than 0.3, continue the following operation.</li>
	</ol>
	</li>
	<li>Place the T-shaped correction frame in the center of the moving area to ensure that the axis direction is consistent with the boundary direction of the force platform.</li>
	<li>Select the Start button under the Set Volume Origin section in the Tool pane.</li>
</ol>
2. Participants&#39; preparation
NOTE: Sixteen healthy male national level 1 table tennis players volunteered to participate in the experiment (Ages: 20.75 &#177; 2.06year; Height: 173.25 &#177; 6.65 cm; Weight: 66.50 &#177; 14.27 kg; Training Year: 12.50 &#177; 2.08 year). All of them belong to the Ningbo University table tennis team. Before the formal start of the experiment, the details and process of the experiment were briefly explained to the participants again, and the written informed consent of the participant who met the conditions of the experiment were obtained.
<ol>
	<li>Select participants that are right-handed, have the right leg as dominant, and are in good physical health, free of any form of lower limb disease or injury in the last 6 months. A total of 16 male participants who met the experimental conditions were included in this experiment. The demographic information of participants is shown in Table 1. 
	NOTE: Because there are few left-handed racket users, it was easier to find enough right-handed racket users to participate in this experiment.</li>
	<li>Ask all participants to fill out a questionnaire related to fitness. 
	NOTE: Questions include: Have you had a history of table tennis competition? How often do you take part in table tennis training in a week? Have you suffered any lower-limb disorders and injuries in the last 6 months?</li>
	<li>Ensure that all participants wear professional table tennis match shoes as well as identical t-shirts and tight-fitting pants. Have all participants use the same professional table tennis racket.</li>
	<li>Give each participant 5 min to adapt to the experimental environment and 15 min to warm up with light running on the professional treadmill and stretching. Due to the short duration of the experiment, restrict subjects from eating and drinking during the formal experiment in order to keep them in a stable state. 
	NOTE: Participants first completed a 5 min jog at an adaptive speed on the lab&#39;s professional running table, followed by a 5 min stretch of their lower limb muscles. Finally, they practiced table tennis footwork technique for 5 min. After completing the warm-up task, the participants were given 2 min to adjust their state. The formal data collection began.</li>
</ol>
3. Static calibration
<ol>
	<li>Click on the Data Management button on the toolbar.</li>
	<li>Click on the New Database tab on the toolbar, click on the Location, and then import the description of the trial. Select Clinical Template and click on the Create button.</li>
	<li>Select the name of the database created in the Open Database window. Then, click on the green New Patient Category button, the yellow New Patient button, and the gray New Session button to create experimental information in the newly opened screen.</li>
	<li>Click on Subjects to create a New Subject data set in the Nexus main pane.</li>
	<li>Click on the Start button in the Subject Capture section to create a static model. Click on the Stop button when the image frames are at 140-200 to finish the establishment of the static model. 
	&#8203;NOTE: The participants were asked to stand on a force platform during the experiment. They were asked to maintain a stable posture with their hands folded and raised on their chest, looking ahead, and their feet shoulder-width apart.</li>
</ol>
4. Dynamic trials
<ol>
	<li>As shown in Figure 1, place the table tennis table and ball basket in the experimental environment to ensure that the subjects have enough space to execute two kinds of footwork. 
	NOTE: The table tennis table and balls are up to the standards of professional events.</li>
	<li>Ask the participant to hold the ready position, When the experimenter gives the start command, ask the coach to serve the table tennis balls to the first and final impact area, respectively.
	<ol>
		<li>Before the formal experiment begins, give the participants enough time to get accustomed to this position through practice.</li>
		<li>Ask the participants to start on the left side of the table, about half a meter away from the table. Then, ask them to hit the first and second served ball by forehand with maximum force and return to the ready position after finishing the second stroke task.</li>
		<li>Ask the participants to first use the chasse step footwork to complete 5 successful strokes, and then use the cross-step footwork to complete 5 successful strokes.</li>
	</ol>
	</li>
	<li>In the software, click on the Capture button in the pressure platform to start the recording and click on the Stop button to end the recording. Repeat five times for each participant. 
	&#8203;NOTE: If the shot is not within the range of the target area, or if the subject&#39;s right foot is not fully on the force platform, the measurement will be re-taken.</li>
</ol>
5. Post-processing
<ol>
	<li>Double-click on the trial name in the Data Management window. Click on the Reconstruct Pipeline and Labels buttons in the toolbar to display the experiment demonstration.</li>
	<li>In the Perspective window, move the blue triangle on the time bar to intercept the desired time interval.</li>
	<li>Select the Dynamic Plug-in Gait that is in the Subject Calibration pane. Click on the Start button to run and export the data.</li>
</ol>
6. Statistical analysis
<ol>
	<li>Analyze all data using professional statistical software. Run the Shapiro-Wilks tests to check the normal distribution for all variables.</li>
	<li>Use a paired t-test to compare kinetics characteristics of chasse step footwork and cross-step footwork during table tennis stroke.</li>
	<li>Set the significance level at p &#60; 0.05. The results are presented as the mean &#177; the standard deviation throughout the text unless otherwise stated.</li>
</ol>

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No potential conflict of interest was reported by the authors.

The aim of this study is to investigate the ground reaction force characteristics between cross-step and chasse steps during stroke in table tennis. The key findings of this study are stated here. The anterior ground reaction force of cross-step footwork was significantly larger than the chasse step footwork. The lateral ground reaction force of cross-step footwork was significantly lower than the chasse step footwork. The vertical ground reaction force of cross-step footwork was significantly lower than the chasse step ...

Table tennis has developed continuously in sports training and competition practice for more than 100 years1. With economic globalization and cultural exchanges, table tennis has developed rapidly in various countries2,3. In Croatia, for example, table tennis is not only played in clubs, but also in universities, schools, and even in dormitories4. For athletes, the establishment of sports analysis is helpful for training and competition5. In table tennis competitions, players need good strategies to try to win the match6. Additionally, footwork is a skill that must be mastered in table tennis, and it is also the basis and one of the key points of table tennis training. The chasse step and cross-step are the basic steps of table tennis7. Every sports skill has a basic mechanical structure. The study of biomechanics is of high interest to the progress and development of table tennis skills. In training and competition, table tennis players find the accurate position through their steps7. Therefore, it is necessary to study the step of table tennis.
There are differences in the step of table tennis players from different regions, with Asian players using steps more frequently than European players both during training and in competition8. During competition, a high-level table tennis player will hit the ball in a shorter time, at a more steady step, and have enough time to hit the next ball9. In table tennis, because of the cross-step hitting action, in most cases it is a technical action to save the ball, leading to the inability to complete the hitting action with high quality. On the contrary, different from cross-step hitting, chasse step hitting is a common technical action, so athletes can better grasp the hitting technical action through practice to ensure the quality of their stroke. A chasse step is when the drive leg (right leg) moves to the right side (toward the ball) and then the left leg follows to move. A cross-step is when the drive leg (right leg) moves to the right side (toward the ball) with a large distance, and the left leg does not move.
Through previous studies, lower limb muscles play an important role in table tennis performance10. Table tennis has similarities with tennis moves. There are differences in the driving stability of lower limbs of tennis players with different levels of serving skill11. Table tennis involves knee flexion and asymmetrical torsion of the trunk12. In order to improve the skills of table tennis players, attention should be paid to the rotation of the pelvis13. When playing forehand loop, excellent table tennis players have a better sole control ability14. High-level table tennis players can better control the plantar pressure deviation, increase the inner and outer pressure deviation, and reduce the front and back pressure deviation15. Compared with a straight shot, a diagonal shot has a greater knee extension during the swing16. Table tennis service technology is diverse and has complex biomechanical characteristics. Compared with standing serves, squatting serves require higher lower-limb drive17. Compared with beginners, elite athletes are more flexible in their stride in cross-step exercises7.
In light of the above, with the increasing progress of science and the continuous development of table tennis skills, more and more players and researchers have joined table tennis, which requires high-quality biomechanical research to support the sport. However, due to the complexity of table tennis, it is difficult for researchers to measure the biomechanics1. There are few studies on the biomechanics of the lower limbs of table tennis. The purpose of this study was to measure the ground reaction force of elite college table tennis players in the movement of the racket lead and swing in chasse step and cross-step. The ground reaction force data of the two steps are compared. The first hypothesis of this study is that the chasse step and cross-step have different ground reaction force characteristics. The ground reaction force of chasse step and cross-step is used to obtain the kinetic data of two kinds of steps, which provides guidance and suggestions for table tennis players.

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			<td>14 mm Diameter Passive Retro-reflective Marker</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>n=22</td>
		</tr>
		<tr>
			<td>Double Adhesive Tape</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>For fixing markers to skin</td>
		</tr>
		<tr>
			<td>Force Platform</td>
			<td>Advanced Mechanical Technology, Inc.</td>
			<td></td>
			<td>Measure ground reaction force</td>
		</tr>
		<tr>
			<td>Motion Tracking Cameras</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>n= 8</td>
		</tr>
		<tr>
			<td>T-Frame</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>-</td>
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		<tr>
			<td>Valid Dongle</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>Vicon Nexus 1.4.116</td>
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		<tr>
			<td>Vicon Datastation ADC</td>
			<td>Oxford Metrics Ltd., Oxford, UK</td>
			<td></td>
			<td>-</td>
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comparison of kinetic characteristics of footwork during stroke in table tennis: cross-step and chasse step

The cross-step and chasse step are the basic steps of table tennis. This study presents a protocol to investigate the ground reaction force characteristics between cross-step and chasse step during stroke in table tennis. Sixteen healthy male national level 1 table tennis players (Age: 20.75 &plusmn; 2.06 years) volunteered to participate in the experiment after understanding the purpose and details of the experiment. All participants were asked to hit the ball into the target zone by cross-step and chasse step, respectively. The ground reaction force in the anterior-posterior, medial-lateral, and vertical directions of the participant was measured by a force platform. The key finding of this study was that: the posterior ground reaction force of cross-step footwork (0.89 &plusmn; 0.21) was significantly large (P = 0.014) than the chasse step footwork (0.82 &plusmn; 0.18). However, the lateral ground reaction force of cross-step footwork (-0.38 &plusmn; 0.21) was significantly lower (P &lt; 0.001) than chasse step footwork (-0.46 &plusmn; 0.29) as well as the vertical ground reaction force of cross-step footwork (1.73 &plusmn; 0.19) was significantly lower (P &lt; 0.001) than chasse step footwork (1.9 &plusmn; 0.33). Based on the mechanism of the kinetic chain, the better lower limb dynamic performance of sliding stroke may be conducive to energy transmission and thus bring gain to the swing speed. Beginners should start from the chasse step to hit the ball technically, and then practice the skill of cross-step.

As shown in Figure 2 and Table 2, the posterior ground reaction force of the cross-step footwork (0.89 &#177; 0.21) was significantly larger (P = 0.014) compared with the chasse step footwork (0.82 &#177; 0.18). However, the lateral ground reaction force of cross-step footwork (-0.38 &#177; 0.21) was significantly lower (P &#60; 0.001) than the chasse step footwork (-0.46 &#177; 0.29). Additionlly, the vertical ground reaction force of cross-step footwork (1.73 &#177; 0.19) ...

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Comparison of Kinetic Characteristics of Footwork during Stroke in Table Tennis: Cross-Step and Chasse Step

This study presents a protocol to investigate the ground reaction force characteristics between cross-step and chasse step during stroke in table tennis.

The cross-step and chasse step are the basic steps of table tennis. This study presents a protocol to investigate the ground reaction force ...

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2.6K Views.  Ningbo University. This study presents a protocol to investigate the ground reaction force characteristics between cross-step and chasse step during stroke in table tennis.

Video: Comparison of Kinetic Characteristics of Footwork during Stroke in Table Tennis: Cross-Step and Chasse Step

Compensatory Limb Use and Behavioral Assessment of Motor Skill Learning Following Sensorimotor Cortex Injury in a Mouse Model of Ischemic Stroke

Mouse models have become increasingly popular in the field of behavioral neuroscience, and specifically in studies of experimental stroke. As models advance, it is important to develop sensitive behavioral measures specific to the mouse. The present protocol describes a skilled motor task for use in mouse models of stroke. The Pasta Matrix Reaching Task functions as a versatile and sensitive behavioral assay that permits experimenters to collect accurate outcome data and manipulate limb use to mimic human clinical phenomena including compensatory strategies (i.e., learned non-use) and focused rehabilitative training. When combined with neuroanatomical tools, this task also permits researchers to explore the mechanisms that support behavioral recovery of function (or lack thereof) following stroke. The task is both simple and affordable to set up and conduct, offering a variety of training and testing options for numerous research questions concerning functional outcome following injury. Though the task has been applied to mouse models of stroke, it may also be beneficial in studies of functional outcome in other upper extremity injury models.

Mouse models have become increasingly popular in studies of behavioral neuroscience. As models advance, it is important to develop sensitive behavioral measures specific to the mouse. This protocol describes the Pasta Matrix Reaching Task, which is a skilled motor task for use in mouse models of stroke.

Mouse models have become increasingly popular in the field of behavioral neuroscience, and specifically in studies of experimental stroke. As models ...

Transcranial Direct Current Stimulation and Simultaneous  Functional Magnetic Resonance Imaging

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp to manipulate cortical excitability and, consequently, behavior and brain function. In the last decade, numerous studies have addressed short-term and long-term effects of tDCS on different measures of behavioral performance during motor and cognitive tasks, both in healthy individuals and in a number of different patient populations. So far, however, little is known about the neural underpinnings of tDCS-action in humans with regard to large-scale brain networks. This issue can be addressed by combining tDCS with functional brain imaging techniques like functional magnetic resonance imaging (fMRI) or electroencephalography (EEG).
In particular, fMRI is the most widely used brain imaging technique to investigate the neural mechanisms underlying cognition and motor functions. Application of tDCS during fMRI allows analysis of the neural mechanisms underlying behavioral tDCS effects with high spatial resolution across the entire brain. Recent studies using this technique identified stimulation induced changes in task-related functional brain activity at the stimulation site&#160;and also in more distant brain regions, which were associated with behavioral improvement. In addition, tDCS administered during resting-state fMRI allowed identification of widespread changes in whole brain functional connectivity.
Future studies using this combined protocol should yield new insights into the mechanisms of tDCS action in health and disease and new options for more targeted application of tDCS in research and clinical settings. The present manuscript describes this novel technique in a step-by-step fashion, with a focus on technical aspects of tDCS administered during fMRI.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique. It has successfully been used in basic research and clinical settings to modulate brain function in humans. This article describes the implementation of tDCS and simultaneous functional magnetic resonance imaging (fMRI), to investigate the neural basis of tDCS effects.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that uses weak electrical currents administered to the scalp ...

fMRI Validation of fNIRS Measurements During a Naturalistic Task

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced version of the task using fMRI (functional magnetic resonance imaging). Recently, it has been shown that fNIRS can accurately record functional brain activities equivalent to those concurrently recorded with functional magnetic resonance imaging for classic psychophysical tasks and simple finger tapping paradigms. However, an often quoted benefit of fNIRS is that the technique allows for studying neural mechanisms of complex, naturalistic behaviors that are not possible using the constrained environment of fMRI. Our goal was to extend the findings of previous studies that have shown high correlation between concurrently recorded fNIRS and fMRI signals to compare neural recordings obtained in fMRI procedures to those separately obtained in naturalistic fNIRS experiments. Specifically, we developed a modified version of the dance video game Dance Dance Revolution (DDR) to be compatible with both fMRI and fNIRS imaging procedures. In this methodology we explain the modifications to the software and hardware for compatibility with each technique as well as the scanning and calibration procedures used to obtain representative results. The results of the study show a task-related increase in oxyhemoglobin in both modalities and demonstrate that it is possible to replicate the findings of fMRI using fNIRS in a naturalistic task. This technique represents a methodology to compare fMRI imaging paradigms which utilize a reduced-world environment to fNIRS in closer approximation to naturalistic, full-body activities and behaviors. Further development of this technique may apply to neurodegenerative diseases, such as Parkinson&#8217;s disease, late states of dementia, or those with magnetic susceptibility which are contraindicated for fMRI scanning.

We present a method to compare functional brain activity recorded during a naturalistic task using fNIRS with activity recorded during fMRI.

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced ...

Utilizing Electroencephalography Measurements for Comparison of Task-Specific Neural Efficiencies: Spatial Intelligence Tasks

Spatial intelligence is often linked to success in engineering education and engineering professions. The use of electroencephalography enables comparative calculation of individuals&#39; neural efficiency as they perform successive tasks requiring spatial ability to derive solutions. Neural efficiency here is defined as having less beta activation, and therefore expending fewer neural resources, to perform a task in comparison to other groups or other tasks. For inter-task comparisons of tasks with similar durations, these measurements may enable a comparison of task type difficulty. For intra-participant and inter-participant comparisons, these measurements provide potential insight into the participant&#39;s level of spatial ability and different engineering problem solving tasks. Performance on the selected tasks can be analyzed and correlated with beta activities. This work presents a detailed research protocol studying the neural efficiency of students engaged in the solving of typical spatial ability and Statics problems. Students completed problems specific to the Mental Cutting Test (MCT), Purdue Spatial Visualization test of Rotations (PSVT:R), and Statics. While engaged in solving these problems, participants&#39; brain waves were measured with EEG allowing data to be collected regarding alpha and beta brain wave activation and use. The work looks to correlate functional performance on pure spatial tasks with spatially intensive engineering tasks to identify the pathways to successful performance in engineering and the resulting improvements in engineering education that may follow.

This manuscript describes an approach to measure neural activity of humans while solving spatially focused engineering problems. The electroencephalogram methodology helps interpret beta brain wave measurements in terms of neural efficiency, with the aim of ultimately enabling comparisons of task performance both between problem types and between participants.

Spatial intelligence is often linked to success in engineering education and engineering professions. The use of electroencephalography enables ...

Investigating the 'Uncatchable Smile' in Leonardo da Vinci's La Bella Principessa: A Comparison with the Mona Lisa and Pollaiuolo's Portrait of a Girl

This paper discusses how the &#39;Uncatchable Smile&#39; illusion in Leonardo da Vinci&#39;s La Bella Principessa portrait was discovered. Kemp and Cotte1 described the expression of the Princess as ambiguous and &#34;subtle to an inexpressible degree&#34;. A combination of three methods was used (inter-observation, structured interviews, and psychophysical experiments) to identify what may underlie this &#39;ambiguity&#39;. The inter-observation and the structured interview methods were firstly applied to generate experimental hypotheses that were successively tested by a series of psychophysical experiments. The combination of these research methods minimizes the impact of the researcher&#39;s beliefs and biases in the development of the research design. It emerged that the ambiguity in La Bella Principessa is triggered by a change in the perceived level of contentment in her facial expression and that this perceptual change is attributable to a visual illusion relating to her mouth. Moreover, it was found that a similar effect can be observed in the Mona Lisa. As the smile in La Bella Principessa disappears as soon as the viewer tries to &#39;catch it&#39;, we named this visual illusion the &#39;Uncatchable Smile&#39;. The elusive quality of the Mona Lisa&#39;s smile2 is probably why the portrait is so famous, and so the existence of a similar ambiguity in a portrait painted by Leonardo prior to the Mona Lisa is even more interesting.

Investigating the &#039;Uncatchable Smile&#039; in Leonardo da Vinci&#039;s La Bella Principessa: A Comparison with the Mona Lisa and Pollaiuolo&#039;s Portrait of a Girl

This paper discusses the methodology used to reveal the &#39;Uncatchable Smile&#39; illusion in Leonardo da Vinci&#39;s La Bella Principessa portrait. A combination of three methods was used (inter-observation, structured interviews, and psychophysical experiments), which led to an investigation that shaped itself without prior beliefs, thus reducing potential researcher bias.

This paper discusses how the &#39;Uncatchable Smile&#39; illusion in Leonardo da Vinci&#39;s La Bella Principessa portrait was discovered. Kemp and Cotte1 ...

Mobile Game-based Virtual Reality Program for Upper Extremity Stroke Rehabilitation

Stroke rehabilitation requires repetitive, intensive, goal-oriented therapy. Virtual reality (VR) has the potential to satisfy these requirements. Game-based therapy can promote patients&#39; engagement in rehabilitation therapy as a more interesting and a motivating tool. Mobile devices such as smartphones and tablet PCs can provide personalized home-based therapy with interactive communication between patients and clinicians. In this study, a mobile VR upper extremity rehabilitation program using game applications was developed. The findings from the study show that the mobile game-based VR program effectively promotes upper extremity recovery in patients with stroke. In addition, patients completed two weeks of treatment using the program without adverse effects and were generally satisfied with the program. This mobile game-based VR upper extremity rehabilitation program can substitute for some parts of the conventional therapy that are delivered one-on-one by an occupational therapist. This time-efficient, easy to implement, and clinically effective program would be a good candidate tool for tele-rehabilitation for upper extremity recovery in patients with stroke. Patients and therapists can collaborate remotely through these e-health rehabilitation programs while reducing economic and social costs.

Here, we present a protocol to develop and apply a mobile game-based virtual reality program for the recovery of upper limb dysfunction in patients with stroke. The present study shows that the mobile program is feasible and effectively promotes upper limb recovery in stroke patients.

Stroke rehabilitation requires repetitive, intensive, goal-oriented therapy. Virtual reality (VR) has the potential to satisfy these requirements. ...

Eye Tracking During Visually Situated Language Comprehension: Flexibility and Limitations in Uncovering Visual Context Effects

The present work is a description and an assessment of a methodology designed to quantify different aspects of the interaction between language processing and the perception of the visual world. The recording of eye-gaze patterns has provided good evidence for the contribution of both the visual context and linguistic/world knowledge to language comprehension. Initial research assessed object-context effects to test&#160;theories of modularity in language processing. In the introduction, we describe how subsequent investigations have taken the role of the wider visual context in language processing as a research topic in its own right, asking questions such as how our visual perception of events and of speakers contributes to&#160;comprehension informed by&#160;comprehenders&#39; experience. Among the examined aspects of the visual context are actions, events, a speaker&#39;s gaze, and emotional facial expressions, as well as spatial object configurations. Following an overview of the eye-tracking method and its different applications, we list the key steps of the methodology in the protocol, illustrating how to successfully use it to study visually-situated language comprehension. A final section presents three sets of representative results and illustrates the benefits and limitations of eye tracking for investigating the interplay between the perception of the visual world and language comprehension.

The present article reviews an eye-tracking methodology for studies on language comprehension. To obtain reliable data, key steps of the protocol must be followed. Among these are the correct set-up of the eye tracker (e.g., ensuring good quality of the eye and head images) and accurate calibration.

The present work is a description and an assessment of a methodology designed to quantify different aspects of the interaction between language processing ...

Computerized Adaptive Testing System of Functional Assessment of Stroke

The computerized adaptive testing system of the functional assessment of stroke (CAT-FAS) can simultaneously assess four functions (motor functions of the upper and lower extremities, postural control, and basic activities of daily living) with sufficient reliability and administrative efficiency. CAT, a modern measurement method, aims to provide a reliable estimate of the examinee's level of function rapidly. CAT administers only a few items whose item difficulties match an examinee's level of function and, thus, the administered items of CAT can provide sufficient information to reliably estimate the examinee's level of function in a short time. The CAT-FAS was developed through four steps: (1) determining the item bank, (2) determining the stopping rules, (3) validating the CAT-FAS, and (4) establishing a platform of online administration. The results of this study indicate that the CAT-FAS has sufficient administrative efficiency (average number of items = 8.5) and reliability (group-level Rasch reliability: 0.88 - 0.93; individual-level Rasch reliability: &#8805;70% of patients had Rasch reliability score &#8805;0.90) to simultaneously assess four functions in patients with stroke. In addition, because the CAT-FAS is a computer-based test, the CAT-FAS has three additional advantages: the automatic calculation of scores, the immediate storage of data, and the easy exporting of data. These advantages of the CAT-FAS will be beneficial to data management for clinicians and researchers.

Here, we present a protocol to develop the computerized adaptive testing system of the functional assessment of stroke (CAT-FAS). The CAT-FAS can simultaneously assess four functions (two motor functions [upper and lower extremities], postural control, and basic activities of daily living) with sufficient reliability and administrative efficiency.

The computerized adaptive testing system of the functional assessment of stroke (CAT-FAS) can simultaneously assess four functions (motor functions of the ...

A Middle Cerebral Artery Occlusion Technique for Inducing Post-stroke Depression in Rats

Post-stroke depression (PSD) is the most recurrent of all psychiatric complications resulting from an ischemic stroke. A greater majority (about 60%) of all ischemic stroke patients suffer from PSD, a disorder considered to be an ischemic stroke-related precursor for increased death and degradation in health. The pathophysiology of PSD is still obscure. To study the mechanism of development and occurrence of PSD further, and to find out a therapy, we attempted to develop a new protocol that requires occluding the middle cerebral artery (MCA) via the internal carotid artery (ICA) in rats. This protocol describes a model of PSD induced in rats through the middle cerebral artery occlusion (MCAO). Also used in the experiment are the Porsolt forced swim test and the sucrose preference test to confirm and evaluate the depressive mood of the rats under investigation. Rather than inserting the catheter through the external carotid artery (ECA), as stipulated for the original procedure, this MCAO technique has the monofilament passing directly through the ICA. This MCAO technique was developed a few years ago and leads to a reduction in mortality and variability. It is generally accepted that the criteria used are preferred in the selection of biological models. The data obtained with this protocol show that this model of MCAO could be a way of inducing PSD in rats and could potentially lead to the understanding of the pathophysiology and the future development of new drugs and other neuroprotective agents.

Here we present a protocol to induce post-stroke depression in rats by occluding the middle cerebral artery via the internal carotid artery. We use the Porsolt forced swim test and the sucrose preference test to confirm and evaluate induced depressive moods.

Post-stroke depression (PSD) is the most recurrent of all psychiatric complications resulting from an ischemic stroke. A greater majority (about 60%) of ...

Evaluating Skilled Prehension in Mice Using an Auto-Trainer

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that permits the mouse to reach out of its cage and retrieve food pellets. Minimal food restriction is employed to encourage the mice to perform the food retrieval from the slot. As the mice begin to associate coming to the slot for food, the pellets are manually pulled away to stimulate extension and pronation of their paw to grasp and retrieve the pellet through the frontal slot. When the mice begin to reach for the pellets as they arrive at the slot, the behavioral assay can be performed by measuring the rate at which they successfully grasp and retrieve the desired pellet. They are then introduced to an auto-trainer that automates both the process of providing food pellets for the mouse to grasp, and the recording of successful and failed reaching and grasping attempts. This allows for the collection of reaching data for multiple mice with minimal effort, to be used in experimental analysis as appropriate.

Method to assess the impact of training on motor skills is a useful tool. Unfortunately, most behavioral assessments can be labor intensive and/or expensive.We describe here a robotic method of assessing prehension (reach-to-grasp) skill in mice.

We describe a method to introduce na&#239;ve mice to a novel prehension (reach-to-grasp) task. Mice are housed singly in cages with a frontal slot that ...