This study was supported by the Seoul National University Bundang Hospital Research Fund (14-2015-022) and by the Ministry of Trade Industry &#38; Energy(MOTIE, Korea), Ministry of Science &#38; ICT(MSIT, Korea), and Ministry of Health &#38; Welfare(MOHW, Korea) under Technology Development Program for AI-Bio-Robot-Medicine Convergence (20001650). We would like to thank Su-Bin Park, Nu-Ri Kim and Ye-Lin Jang for helping to prepare and proceed with the video shooting.

All procedures were reviewed and approved by the Seoul National University Bundang Hospital Institutional Review Board (IRB). To recruit healthy participants, posters were used to advertise around the hospital.
1. Experimental set-up
<ol>
	<li>Participant recruitment
	<ol>
		<li>Perform the subject screening process using the following inclusion criteria: 1) healthy, between 18 and 50 years old; 2) right-handed, assessed by Edinburgh handedness inventory14; 3) able to wear the head mount display for VR and to detect objects within VR; and 4) no history of diseases affecting the brain, such as stroke, Parkinson&#39;s disease, or traumatic brain injury. 
		NOTE: These criteria were designed to screen participants with the ability to participate in the experiment and regulate factors affecting the results.</li>
		<li>Recruit participants and provide a detailed explanation of the entire study and expected clinical issues. Consent must be obtained prior to inclusion.</li>
	</ol>
	</li>
	<li>Experimental system 
	NOTE: A customized VPAT system using an immersive VR system and depth-sensing camera was used. Functional infrared spectroscopy (fNIRS) was simultaneously used to investigate the cortical activation. VPAT and fNIRS were linked together for the experiment (Figure 1).
	<ol>
		<li>VPAT system 
		NOTE: The VPAT system consists of a head mount display for VR implementation, a hand tracking sensor that can recognize hand gestures for intuitive input by the user, and a hardware push button. The overall composition is shown in Figure 1.
		<ol>
			<li>Make sure that the hand tracking sensor is not tilted in front of the head mount display.</li>
			<li>Check that the reference camera for the VR system is properly installed on top of the front monitor.</li>
			<li>Secure the push button in a location near the hand to be used by the participant for the experiment.</li>
			<li>Run the software to make sure there are no errors. 
			NOTE: The virtual environment was implemented to match the actual environment as close as possible. The task was performed through hand pointing within the virtual environment and button input through the push button.</li>
		</ol>
		</li>
		<li>fNIRS
		<ol>
			<li>Use a commercial fNIRS system including a personal computer (PC), 31 optodes (15 light sources and 16 detectors), textile EEG caps, and data recording software.</li>
		</ol>
		</li>
		<li>Linkage between VPAT system and fNIRS (Figure 1).
		<ol>
			<li>Use the remote keyboard control software using TCP/IP communication to synchronize the starting event in the VPAT system with the timing of recording in the fNIRS system.</li>
			<li>Use the remote command key in the computer to start fNIRS recording.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
2. Experimental set-up (Figure 2)
<ol>
	<li>fNIRS measurement setting
	<ol>
		<li>Place the participant in a chair with his/her back in a straight posture, about fifteen centimeters away from the table. Confirm that the participant&#39;s hand does not hit the table when reaching out.</li>
		<li>For fNIRS cap setting, select the cap size according to the participant&#39;s head circumference. Place the cap so that the vertex (Cz) is located at the intersection of the midpoint between the inion and nasion and the midpoint between the left preauricular and right preauricular areas. Display the montage on the screen and connect 15 sources and 24 detectors to the montage. If necessary to improve the gain from the light source, use conductive gel after hair preparation and insert the optode. Have the participant wear a retaining cap. 
		NOTE: The study used three different sizes of textile EEG caps with circumferences of 54, 56, and 58 cm.</li>
		<li>For software setting (calibration, etc.), run the fNIRS system software and load the neglect montage.</li>
		<li>Let the montage be displayed on the screen and set 15 sources and 24 detectors according to the montage (Figure 3).</li>
		<li>Press the calibrate button. If &#34;Lost&#34; is displayed on the screen, repeat the hair preparation, and then recalibrate.</li>
	</ol>
	</li>
	<li>VPAT system setting
	<ol>
		<li>Connect the HMD, reference camera, and Leap motion camera, and push the button connecting the computer to set up the VPAT system.</li>
		<li>Mount the virtual reality head-mounted display (VR HMD) on the participant&#39;s head over the cap for fNIRS. Make sure to avoid movement of the cap.</li>
		<li>Run the VPAT software. Enter the participant&#39;s information (name abbreviation, age, handedness) and press the &#34;Start&#34; button.</li>
		<li>Confirm the visualization of the virtual hand in the display. Proceed with a two-step calibration (i.e., screen calibration and target distance calibration).</li>
		<li>Instruct the participant to watch the red cross mark (+) in the center, then press the &#34;r&#34; key to calibrate the screen. 
		NOTE: Screen calibration places the virtual space in front of the user&#39;s visual range by recentering the coordinate system.</li>
		<li>Instruct the participant to point to the target (i.e., ball) with his or her right hand, then press the &#34;O&#34; key to calibrate the hand position. 
		NOTE: In our study, the object that the participant had to target was a white ball on a pink stick that came down from the top of the view. Target distance calibration places the target within the reach of the user. This is used to correctly position the target during the experiment.</li>
		<li>After calibration, press the &#34;w&#34; key to begin the experiment.</li>
	</ol>
	</li>
	<li>VPAT and fNIRS linkage setting
	<ol>
		<li>Use the event synchronization software to enter the trigger for analysis into fNIRS and connect VPAT to fNIRS.</li>
		<li>For time synchronization between VPAT and fNIRS, connect the computers with the two systems to the same network, and then synchronize them through the self-produced key transferring program.</li>
		<li>After connecting through the IP and Port inputs of both computers, start the experiment session via the &#34;w&#34; key in the VPAT program. The event synchronization software is executed automatically, and triggers during execution are automatically transferred to fNIRS and saved.</li>
		<li>After the experiment, obtain the software auto-termination and VPAT data. Then stop the VPAT and fNIRS system software. 
		NOTE: The participants must return their hands to their original position after pointing during the VPAT experiment.</li>
	</ol>
	</li>
</ol>
3. Experiment to validate VPAT system
<ol>
	<li>Block designed experiment with fNIRS recording (Figure 4)
	<ol>
		<li>After completing the set-up process in step 2, confirm the participant&#39;s readiness to start the experiment.</li>
		<li>Start the VPAT system without the prism mode and instruct the participant to point to the target in the VR system immediately for familiarization with the procedure.</li>
		<li>Each phase consists of blocks for pointing, clicking, or resting (Figure 4). Again, instruct the participant to click on the button or point to the target in the VR system with their right index finger as quickly as possible.</li>
		<li>Start the experiment with four phases simultaneously with fNIRS recording by clicking the start key. 
		NOTE: During the pointing task, the white ball had to be touched within a fixed time.
		<ol>
			<li>Instruct the participants to point, click, or rest when the appropriate icon appears. 
			NOTE: During the task, pointing and clicking were indicated by an icon directly above the white ball and right side of the timer bar. The time to perform the task was indicated by the timer bar as shown in Figure 2.</li>
			<li>Tell the participant to touch the target that appears on the left or right side within 3 s. For the clicking block, instruct the participant to press the push button. 
			NOTE: The target set containing the white ball was located at a distance of -10&#176; or 10&#176; from the participant&#39;s center, obtained by calibration. The target set appeared randomly on the right or left side. According to the experimental design, the target appeared for 3 s, then disappeared, and then regenerated to a new position.</li>
			<li>Ensure that the participant performs the same way when the phase is switched. 
			NOTE: In the pointing task, Virtual Prism Adaptation Mode showed a deviation of 10&#176; or 20&#176; to the left side of the imaginary hand in the VR space relative to the participant&#39;s head. Zero degrees indicated that the positions of the virtual hand and the actual hand coincided. 
			NOTE: The experiment (Figure 4) consists of a total of four phases, with each phase consisting of pointing and clicking or rest alternately (Phase 1 and 4 were pointing and clicking, and phase 2 and 3 were pointing and resting).</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
4. Data analysis
<ol>
	<li>Pointing error analysis 
	NOTE: The data were stored from the moment the experimenter pressed the start button &#34;w&#34;. The data were automatically stored at about 60 Hz every frame through the VPAT software. The phase name, elapsed time, and virtual index finger position were stored over time. The pointing error was the angle value between the target and index finger, centered on the participant&#39;s head position.
	<ol>
		<li>Classify the pointing task data by phases (pre-VPAT, VPAT 10&#176;, VPAT 20&#176;, post-VPAT).</li>
		<li>Classify the data of the pointing task and the clicking task in the data of each phase (phase 1 and 4).</li>
		<li>Classify the data by sub-phase in units of 30 s according to each phase and each type of task.</li>
		<li>Extract the median value of 10 trial error (pointing error) values from the index finger position data for median pointing error analysis.</li>
		<li>Use the repeated measures analysis of variance test (ANOVA) to analyze the difference between each phase. 
		NOTE: In the case of hand tracking using the Leap motion sensor, outliers were due to occlusion or false detection of the hand posture. With the exception of false hand position data, the median value was used to find the representative pointing error value in the sub-phase.</li>
	</ol>
	</li>
	<li>fNIRS data processing
	<ol>
		<li>Launch the fNIRS analysis software and load the raw data file and probe information.</li>
		<li>Perform a marker setting process by editing the event record to verify each condition during the experiment.</li>
		<li>Carry out data preprocessing by deleting the experimentally irrelevant time intervals, remove artifacts, such as steps and spikes, and apply frequency filters to exclude experimentally irrelevant frequency bands. 
		NOTE: All data sets were filtered with a 0.01 Hz high-pass filter and a 0.2 Hz low-pass filter to remove instrumental or physiological noise contributions.</li>
		<li>Specify wavelengths by entering the value of the peak illumination wavelengths (i.e., 760 and 850 nm). Use a physical distance of 3 cm between the source and detector for channel.</li>
		<li>Select the baseline field, which refers to the time period that corresponds to a baseline wherein participants are typically resting quietly. 
		NOTE: We selected the baseline field as the full-time course of the data set, which was the default setting.</li>
		<li>Compute the time series of hemodynamic states to finish the preprocessing from the filtered data.</li>
	</ol>
	</li>
</ol>

<ol><li>Appelros, P., Karlsson, G. M., Seiger, A., Nydevik, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Neglect+and+anosognosia+after+first-ever+stroke%3A+incidence+and+relationship+to+disability%5BTitle%5D)+AND+%22Journal+of+Rehabilitation+Medicine%22%5BJournal%5D)">Neglect and anosognosia after first-ever stroke: incidence and relationship to disability.</a> Journal of Rehabilitation Medicine. 34 (5), 215-220 (2002).</li>
<li>Buxbaum, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Hemispatial+neglect+subtypes%2C+neuroanatomy%2C+and+disability%5BTitle%5D)+AND+%22Neurology%22%5BJournal%5D)">Hemispatial neglect subtypes, neuroanatomy, and disability.</a> Neurology. 62 (5), 749-756 (2004).</li>
<li>Jehkonen, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Visual+neglect+as+a+predictor+of+functional+outcome+one+year+after+stroke%5BTitle%5D)+AND+%22Acta+Neurologica+Scandinavica%22%5BJournal%5D)">Visual neglect as a predictor of functional outcome one year after stroke.</a> Acta Neurologica Scandinavica. 101 (3), 195-201 (2000).</li>
<li>Jehkonen, M., Laihosalo, M., Kettunen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Impact+of+neglect+on+functional+outcome+after+stroke%E2%80%93a+review+of+methodological+issues+and+recent+research+findings%5BTitle%5D)+AND+%22Restorative+Neurology+and+Neuroscience%22%5BJournal%5D)">Impact of neglect on functional outcome after stroke–a review of methodological issues and recent research findings.</a> Restorative Neurology and Neuroscience. 24 (4-6), 209-215 (2006).</li>
<li>Mizuno, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prism+adaptation+therapy+enhances+rehabilitation+of+stroke+patients+with+unilateral+spatial+neglect%3A+a+randomized%2C+controlled+trial%5BTitle%5D)+AND+%22Neurorehabilitation+and+Neural+Repair%22%5BJournal%5D)">Prism adaptation therapy enhances rehabilitation of stroke patients with unilateral spatial neglect: a randomized, controlled trial.</a> Neurorehabilitation and Neural Repair. 25 (8), 711-720 (2011).</li>
<li>Shiraishi, H., Yamakawa, Y., Itou, A., Muraki, T., Asada, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Long-term+effects+of+prism+adaptation+on+chronic+neglect+after+stroke%5BTitle%5D)+AND+%22NeuroRehabilitation%22%5BJournal%5D)">Long-term effects of prism adaptation on chronic neglect after stroke.</a> NeuroRehabilitation. 23 (2), 137-151 (2008).</li>
<li>Yang, N. Y., Zhou, D., Chung, R. C., Li-Tsang, C. W., Fong, K. N. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aYang%2C+NY+%22Rehabilitation+interventions+for+unilateral+neglect+after+stroke%3A+a+systematic+review+from+1997+through+2012%22">Rehabilitation interventions for unilateral neglect after stroke: a systematic review from 1997 through 2012</a>. , (2013).</li>
<li>Rossetti, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prism+adaptation+to+a+rightward+optical+deviation+rehabilitates+left+hemispatial+neglect%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">Prism adaptation to a rightward optical deviation rehabilitates left hemispatial neglect.</a> Nature. 395 (6698), 166-169 (1998).</li>
<li>Barrett, A., Goedert, K. M., Basso, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prism+adaptation+for+spatial+neglect+after+stroke%3A+translational+practice+gaps%5BTitle%5D)+AND+%22Nature+Reviews+Neurology%22%5BJournal%5D)">Prism adaptation for spatial neglect after stroke: translational practice gaps.</a> Nature Reviews Neurology. 8 (10), 567-577 (2012).</li>
<li>Maxton, C., Dineen, R., Padamsey, R., Munshi, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Don%27t+neglect+%27neglect%27-an+update+on+post+stroke+neglect%5BTitle%5D)+AND+%22International+Journal+of+Clinical+Practice%22%5BJournal%5D)">Don't neglect 'neglect'-an update on post stroke neglect.</a> International Journal of Clinical Practice. 67 (4), 369-378 (2013).</li>
<li>Gammeri, R., Turri, F., Ricci, R., Ptak, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Adaptation+to+virtual+prisms+and+its+relevance+for+neglect+rehabilitation%3A+a+single-blind+dose-response+study+with+healthy+participants%5BTitle%5D)+AND+%22Neuropsychol+Rehabilitation%22%5BJournal%5D)">Adaptation to virtual prisms and its relevance for neglect rehabilitation: a single-blind dose-response study with healthy participants.</a> Neuropsychol Rehabilitation. , 1-14 (2018).</li>
<li>Saj, A., Cojan, Y., Assal, F., Vuilleumier, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prism+adaptation+effect+on+neural+activity+and+spatial+neglect+depend+on+brain+lesion+site%5BTitle%5D)+AND+%22Cortex%22%5BJournal%5D)">Prism adaptation effect on neural activity and spatial neglect depend on brain lesion site.</a> Cortex. 119, 301-311 (2019).</li>
<li>Redding, G. M., Wallace, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Generalization+of+prism+adaptation%5BTitle%5D)+AND+%22Journal+of+Experimental+Psychology%3A+Human+Perception+and+Performance%22%5BJournal%5D)">Generalization of prism adaptation.</a> Journal of Experimental Psychology: Human Perception and Performance. 32 (4), 1006-1022 (2006).</li>
<li>Caplan, B., Mendoza, J. E. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aCaplan%2C+B+%22Encyclopedia+of+Clinical+Neuropsychology%22">Encyclopedia of Clinical Neuropsychology</a>. , Springer. 928(2011).</li>
<li>Kim, W. S., Paik, N. J., Cho, S. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aKim%2C+WS+%222017+International+Conference+on+Virtual+Rehabilitation+%28ICVR%29%22">2017 International Conference on Virtual Rehabilitation (ICVR)</a>. , IEEE. 1-2 (2017).</li>
<li>Munafo, J., Diedrick, M., Stoffregen, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+virtual+reality+head-mounted+display+Oculus+Rift+induces+motion+sickness+and+is+sexist+in+its+effects%5BTitle%5D)+AND+%22Experimental+Brain+Research%22%5BJournal%5D)">The virtual reality head-mounted display Oculus Rift induces motion sickness and is sexist in its effects.</a> Experimental Brain Research. 235 (3), 889-901 (2017).</li>
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</ol>

Won-Seok Kim, Sungmin Cho, and Nam-Jong Paik have a patent entitled &#34;Method, system and readable recording medium of creating visual stimulation using virtual model&#34;, number 10-1907181, which is relevant to this work.

This study implemented the prism adaption therapy using a translated hand movement in a VR environment. It investigated whether the deviation implemented was causing angle overshooting and behavioral adaptation, as in conventional prism adaption therapy.
In the median pointing error result (Figure 5) and the first pointing error result, the pointing error changed significantly when the phase was switched. Although some hand-recognition errors were eliminated, ther...

Hemispatial neglect, which affects the ability to perceive the contralateral hemispatial visual field, is a common impairment after stroke1,2. Although rehabilitation after hemispatial neglect is important, due to its association with poor functional and social outcomes, rehabilitation is often underutilized in real clinical practice3,4.
Among the various existing rehabilitation approaches suggested for hemispatial neglect, prism adaptation (PA) therapy has proven effective for recovery and improvement in hemispatial neglect in patients with subacute or chronic stroke5,6,7,8. However, conventional PA is underutilized due to several drawbacks9,10. These include 1) high cost and time requirement due to the prism lens needing to be changed to adjust to the degree of deviation; 2) the need to set up additional materials to be pointed at and to mask the hand trajectory; and 3) PA can only be used by patients who can sit and control their head position.
A recent study reproducing the adaptation effects in the virtual reality (VR) environment reported that it may be possible for the virtual prism adaptation therapy (VPAT) to have different effects depending on the subtypes of neglect11. It was also suggested that cortical activation for PA may vary according to brain lesions12. However, little is known about the cortical activation pattern seen in VR-induced PA.
To overcome these obstacles and promote the use of PA in a clinical setting, we developed a new PA therapy system using an immersive VR technology called virtual prism adaptation therapy (VPAT), via the use of a depth-sensing camera. We designed an immersive VR system with the ability to provide visual feedback about the position of a virtual limb to promote spatial realignment13. Using this immersive VR technology, which mimicked the effect of conventional PA, we designed an experiment to validate the VPAT system in healthy participants.
By conducting our visualized experimental protocol, we investigated whether the new VPAT system can induce behavioral adaptation, similar to conventional PA. Additionally, we would like to explore whether the VPAT system can induce the activation in the cortical regions associated with visuospatial perception or recovery of hemispatial neglect after stroke.

<table><tbody><tr><td>EASYCAP</td><td>Easycap</td><td>C-SAMS</td><td>Platform to accommodate fNIRS optodes</td></tr><tr><td>Leap Motion 3D Motion Controller</td><td>Ultrahaptics</td><td>FBA_LM-C01-US</td><td>Hand detection device attached HMD</td></tr><tr><td>Leap Motion VR Developer Mount for VR Headset</td><td>Ultrahaptics</td><td>VR-UAZ</td><td></td></tr><tr><td>Matlab R2015a</td><td>Mathworks</td><td></td><td>Programming language running with NIRStar</td></tr><tr><td>NIRScout</td><td>Medical Technology LLC</td><td>NSC-CORE</td><td>fNIRS system</td></tr><tr><td>nirsLAB v201605</td><td>Medical Technology LLC</td><td></td><td>Software for analyzing data collected with NIRScout</td></tr><tr><td>NIRStar 14.1</td><td>Medical Technology LLC</td><td></td><td>NIRScout Acquisition Software</td></tr><tr><td>Occulus Rift DK2</td><td>Occulus</td><td></td><td>VR HMD</td></tr><tr><td>PowerMate USB Multimedia Controller</td><td>Griffin Technology</td><td>NA16029</td><td>Push Button in task</td></tr><tr><td>SuperLab 5.0</td><td>Cedrus Corp.</td><td></td><td>Synchronize the stimulus presentations allied to NIRScout</td></tr></tbody></table>

virtual prism adaptation therapy: protocol for validation in healthy adults

Hemispatial neglect is a common impairment after stroke. It is associated with poor functional and social outcomes. Therefore, an adequate intervention is imperative for the successful management of hemispatial neglect. However, the clinical use of various interventions is limited in real clinical practice. Prism adaptation therapy is one of the most evidence-based rehabilitation modalities to treat hemispatial neglect. To overcome any possible shortcoming that may occur with prism therapy, we developed a new system using immersive virtual reality and depth-sensing camera to create a virtual prism adaptation therapy (VPAT). To validate the VPAT system, we designed an experimental protocol investigating the behavioral errors and changes in cortical activation via the VPAT system. Cortical activation was measured by functional near infrared spectroscopy (fNIRS). The experiment consisted of four phases. All four included clicking, pointing or rest applied to right-handed healthy people. Clicking versus pointing was used for investigating the cortical region related with the gross motor task, and pointing with VPAT versus pointing without VPAT was used for investigating the cortical region associated with visuospatial perception. The preliminary results from four healthy participants showed that pointing errors by the VPAT system was similar to the conventional prism adaptation therapy. Further analysis with more participants and fNIRS data, as well as a study in patients with stroke may be required.

Data from four healthy participants (1 man and 3 women) were used as representative results. A pointing error is shown in Figure 5A, with the averages of median value of 10 trials in the sub-phase of each pointing task lasting 30 s. Values on average for the median pointing errors in the first block of each phase were 0.45 &#177; 0.92 (pre-VPAT), 4.69 &#177; 3.08 (VPAT 10&#176;), 5.43 &#177; 2.22 (VPAT 20&#176;), and -5.17 &#177; 1.60 (post-VPAT). The trend of pointing error...

Watch this Scientific Journal Video about Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults at JoVE.com

Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults

This experimental protocol demonstrates the use of virtual prism adaptation therapy (VPAT) in healthy adults and the association between VPAT and functional near infrared spectroscopy to determine the effect of VPAT on cortical activation. Results suggest that VPAT may be feasible and could induce similar behavioral adaptation as conventional prism adaptation therapy.

Hemispatial neglect is a common impairment after stroke. It is associated with poor functional and social outcomes. Therefore, an adequate intervention is ...

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6.8K Views.  Delvine Inc.. This experimental protocol demonstrates the use of virtual prism adaptation therapy (VPAT) in healthy adults and the association between VPAT and functional near infrared spectroscopy to determine the effect of VPAT on cortical activation. Results suggest that VPAT may be feasible and could induce similar behavioral adaptation as conventional prism adaptation therapy.

Video: Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults

Haptic/Graphic Rehabilitation: Integrating a Robot into a Virtual Environment Library and Applying it to Stroke Therapy

Recent research that tests interactive devices for prolonged therapy practice has revealed new prospects for robotics combined with graphical and other forms of biofeedback. Previous human-robot interactive systems have required different software commands to be implemented for each robot leading to unnecessary developmental overhead time each time a new system becomes available. For example, when a haptic/graphic virtual reality environment has been coded for one specific robot to provide haptic feedback, that specific robot would not be able to be traded for another robot without recoding the program. However, recent efforts in the open source community have proposed a wrapper class approach that can elicit nearly identical responses regardless of the robot used. The result can lead researchers across the globe to perform similar experiments using shared code. Therefore modular "switching out"of one robot for another would not affect development time. In this paper, we outline the successful creation and implementation of a wrapper class for one robot into the open-source H3DAPI, which integrates the software commands most commonly used by all robots.

Recently, a vast amount of prospects have come available for human-robot interactive systems. In this paper we outline the integration of a new robotic device with open source software that can rapidly make possible a library of interactive functionality. We then outline a clinical application for a neurorehabilitation application.

Recent research that tests interactive devices for prolonged therapy practice has revealed new prospects for robotics combined with graphical and other ...

Bioengineering

Development of a Virtual Reality Assessment of Everyday Living Skills

Cognitive impairments affect the majority of patients with schizophrenia and these impairments predict poor long term psychosocial outcomes.&#160; Treatment studies aimed at cognitive impairment in patients with schizophrenia not only require demonstration of improvements on cognitive tests, but also evidence that any cognitive changes lead to clinically meaningful improvements.&#160; Measures of &#8220;functional capacity&#8221; index the extent to which individuals have the potential to perform skills required for real world functioning. &#160;Current data do not support the recommendation of any single instrument for measurement of functional capacity.&#160; The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) is a novel, interactive gaming based measure of functional capacity that uses a realistic simulated environment to recreate routine activities of daily living. Studies are currently underway to evaluate and establish the VRFCAT&#8217;s sensitivity, reliability, validity, and practicality.&#160;This new measure of functional capacity is practical, relevant, easy to use, and has several features that improve validity and sensitivity of measurement of function in clinical trials of patients with CNS disorders.

A challenge for proving treatment efficacy for cognitive impairments in schizophrenia is finding the optimizing measurement of skills related to everyday functioning.&#160; The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) is an interactive gaming based computerized measure aimed at skills associated with everyday functioning, including baseline impairments and treatment related changes.

Cognitive impairments affect the majority of patients with schizophrenia and these impairments predict poor long term psychosocial outcomes.&#160; ...

Behavior

Evaluating Flight Performance and Eye Movement Patterns Using Virtual Reality Flight Simulator

Efficient and economical performance evaluation of pilots has become critical to the aviation industry. With the development of virtual reality (VR) and the combination of eye-tracking technology, solutions to meet these needs are becoming a reality. Previous studies have explored VR-based flight simulators, focusing mainly on technology validation and flight training. The current study developed a new VR flight simulator to evaluate pilots' flight performance based on eye movement and flight indicators in a 3D immersive scene. During the experiment, 46 participants were recruited: 23 professional pilots and 23 college students without flight experience. The experiment results showed significant differences in flight performance between participants with and without flight experience, the former being higher than the latter. In contrast, those with flight experience showed more structured and efficient eye-movement patterns. These results of the differentiation of flight performance demonstrate the validity of the current VR flight simulator as a flight performance assessment method. The different eye-movement patterns with flight experience provide the basis for future flight selection. However, this VR-based flight simulator has shortcomings like motion feedback compared to traditional flight simulators. This flight simulator platform is highly flexible except for the apparent low cost. It can meet the diverse needs of researchers (e.g., measuring situation awareness, VR sickness, and workload by adding relevant scales).

A new virtual reality flight simulator was built, which enables efficient and low-cost evaluation of flight performance and eye movement patterns. It also provides a high-potential research tool for ergonomics and other research.

Efficient and economical performance evaluation of pilots has become critical to the aviation industry. With the development of virtual reality (VR) and ...

The Immersive Cleveland Clinic Virtual Reality Shopping Platform for the Assessment of Instrumental Activities of Daily Living

A decline in the performance of instrumental activities of daily living (IADLs) has been proposed as a prodromal marker of neurological disease. Existing clinical and performance-based IADL assessments are not feasible for integration into clinical medicine. Virtual reality (VR) is a powerful yet underutilized tool that could advance the diagnosis and treatment of neurological disease. An impediment to the adoption and scaling of VR in clinical neurology is VR-related sickness resulting from sensory inconsistencies between the visual and vestibular systems (i.e., locomotion problem).
The Cleveland Clinic Virtual Reality Shopping (CC-VRS) platform attempts to solve the locomotion problem by coupling an omnidirectional treadmill with high-resolution VR content, enabling the user to physically navigate a virtual grocery store to simulate shopping. The CC-VRS consists of Basic and Complex shopping experiences; both require walking 150 m and retrieving five items. The Complex experience has additional scenarios that increase the cognitive and motor demands of the task to better represent the continuum of activities associated with real-world shopping. The CC-VRS platform provides objective and quantitative biomechanical and cognitive outcomes related to the user&#39;s IADL performance. Initial data indicate that the CC-VRS results in minimal VR-sickness and is feasible and tolerable for older adults and patients with Parkinson&#39;s disease (PD). The considerations underlying the development, design, and hardware and software technology are reviewed, and initial models of integration into primary care and neurology are provided.

Virtual reality (VR) is a powerful yet underutilized approach to advance the diagnosis and treatment of neurological disease. The Cleveland Clinic Virtual Reality Shopping platform combines state-of-the-art VR content with an omnidirectional treadmill to quantify instrumental activities of daily living-a proposed prodromal marker of neurological disease.

A decline in the performance of instrumental activities of daily living (IADLs) has been proposed as a prodromal marker of neurological disease. Existing ...

Engineering

Integrating VR and Biosensors for Quantitative Motion-Muscle Activity Assessment

Setup for the Quantitative Assessment of Motion and Muscle Activity During a Virtual Modified Box and Block Test

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and independence and may lead to complications. The importance of remote patient evaluation and rehabilitation has recently grown due to limited access to in-person services. For example, the COVID-19 pandemic unexpectedly resulted in strict regulations, reducing access to non-emergent healthcare services. Additionally, remote care offers an opportunity to address healthcare disparities in rural, underserved, and low-income areas where access to services remains limited. 
Improving accessibility through remote care options would limit the number of hospital or specialist visits and render routine care more affordable. Finally, the use of readily available commercial consumer electronics for at-home care can enhance patient outcomes due to improved quantitative observation of symptoms, treatment efficacy, and therapy dosage. While remote care is a promising means to address these issues, there is a crucial need to quantitatively characterize motor impairment for such applications. The following protocol seeks to address this knowledge gap to enable clinicians and researchers to obtain high-resolution data on complex movement and underlying muscle activity. The ultimate goal is to develop a protocol for remote administration of functional clinical tests. 
Here, participants were instructed to perform a medically-inspired Box and Block task (BBT), which is frequently used to assess hand function. This task requires subjects to transport standardized cubes between two compartments separated by a barrier. We implemented a modified BBT in virtual reality to demonstrate the potential of developing remote assessment protocols. Muscle activation was captured for each subject using surface electromyography. This protocol allowed for the acquisition of high-quality data to better characterize movement impairment in a detailed and quantitative manner. Ultimately, these data have the potential to be used to develop protocols for virtual rehabilitation and remote patient monitoring.

Author Spotlight: Enhancing Remote Rehabilitation with Virtual Reality and Electromyography

The protocol described here aims to enhance the quantitative evaluation of upper limb deficits, with the goal of developing additional technology for remote assessment both in the clinic and at home. Virtual reality and biosensor technologies are combined with standard clinical techniques to provide insights into the functioning of the neuromuscular system.

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and ...

Using Brain Activation (nir-HEG/Q-EEG) and Execution Measures (CPTs) in a ADHD Assessment Protocol

Attention Deficit Hyperactivity Disorder (ADHD) is a problem that impacts academic performance and has serious consequences that result in difficulties in scholastic, social and familial contexts. One of the most common problems in the identification of this disorder relates to the apparent over diagnosis of the disorder due to the absence of global protocols for assessment. The research group of School Learning, Difficulties and Academic Performance (ADIR) from the University of Oviedo, has developed a complete protocol that suggests the existence of certain patterns of cortical activation and executive control for identifying ADHD more objectively. This protocol takes into consideration some of the hypothetical determinants of ADHD, including the relationship between activation of selected areas of the brain, and differences in performance on various aspects of executive functioning such as omissions, commissions or response times, using innovative tools of Continuous Performance Testing (based on Virtual Reality CPT and Traditional CPT) and brain activation measures (two different tools, based on Hemoencephalography- nirHEG; and Quantified Electroencephalography --Q-EEG, respectively). This model of assessment aims to provide an effective assessment of ADHD symptomatology in order to design an accurate intervention and make appropriate recommendations for parents and teachers.

Using Brain Activation nir-HEG/Q-EEG and Execution Measures CPTs in a ADHD Assessment Protocol

This work presents a new protocol for the assessment of Attention Deficit Hyperactivity Disorder (ADHD) by providing a more objective diagnostic procedure for this developmental disorder based on the use of innovative tools. It also analyzes the relationship between activation measures and executive function measures.

Attention Deficit Hyperactivity Disorder (ADHD) is a problem that impacts academic performance and has serious consequences that result in difficulties in ...

Neuroscience

Real-time Video Projection in an MRI for Characterization of Neural Correlates Associated with Mirror Therapy for Phantom Limb Pain

Mirror therapy (MT) has been proposed as an effective rehabilitative strategy to alleviate pain symptoms in amputees with phantom limb pain (PLP). However, establishing the neural correlates associated with MT therapy have been challenging given that it is difficult to administer the therapy effectively within a magnetic resonance imaging (MRI) scanner environment. To characterize the functional organization of cortical regions associated with this rehabilitative strategy, we have developed a combined behavioral and functional neuroimaging protocol that can be applied in participants with a leg amputation. This novel approach allows participants to undergo MT within the MRI scanner environment by viewing real-time video images captured by a camera. The images are viewed by the participant through a system of mirrors and a monitor that the participant views while lying on the scanner bed. In this manner, functional changes in cortical areas of interest (e.g., sensorimotor cortex) can be characterized in response to the direct application of MT.

We present a novel combined behavioral and neuroimaging protocol employing real-time video projection for the purpose of characterizing the neural correlates associated with mirror therapy within the magnetic resonance imaging scanner environment in leg amputee subjects with phantom limb pain.

Mirror therapy (MT) has been proposed as an effective rehabilitative strategy to alleviate pain symptoms in amputees with phantom limb pain (PLP). ...

Simultaneous Application of Transcranial Direct Current Stimulation during Virtual Reality Exposure

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that changes the likelihood of neuronal firing through modulation of neural resting membranes. Compared to other techniques, tDCS is relatively safe, cost-effective, and can be administered while individuals are engaged in controlled, specific cognitive processes. This latter point is important as tDCS may predominantly affect intrinsically active neural regions. In an effort to test tDCS as a potential treatment for psychiatric illness, the protocol described here outlines a novel procedure that allows the simultaneous application of tDCS during exposure to trauma-related cues using virtual reality (tDCS+VR) for veterans with posttraumatic stress disorder (NCT03372460). In this double-blind protocol, participants are assigned to either receive 2 mA tDCS, or sham stimulation, for 25 minutes while passively watching three 8-minute standardized virtual reality drives through Iraq or Afghanistan, with virtual reality events increasing in intensity during each drive. Participants undergo six sessions of tDCS+VR over the course of 2-3 weeks, and psychophysiology (skin conductance reactivity) is measured throughout each session. This allows testing for within and between session changes in hyperarousal to virtual reality events and adjunctive effects of tDCS. Stimulation is delivered through a built-in rechargeable battery-driven tDCS device using a 1 (anode) x 1 (cathode) unilateral electrode set-up. Each electrode is placed in a 3 x 3 cm (current density 2.22 A/m2) reusable sponge pocket saturated with 0.9% normal saline. Sponges with electrodes are attached to the participant&#8217;s skull using a rubber headband with the electrodes placed such that they target regions within the ventromedial prefrontal cortex. The virtual reality headset is placed over the tDCS montage in such a way as to avoid electrode interference.

This manuscript outlines a novel protocol to allow the simultaneous application of transcranial direct current stimulation during exposure to warzone trauma-related cues using virtual reality for veterans with posttraumatic stress disorder.

Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that changes the likelihood of neuronal firing through ...

Virtual Reality Tools for Assessing Unilateral Spatial Neglect: A Novel Opportunity for Data Collection

Unilateral spatial neglect (USN) is a syndrome characterized by inattention to or inaction in one side of space and affects between 23-46% of acute stroke survivors. The diagnosis and characterization of these symptoms in individual patients can be challenging and often requires skilled clinical staff. Virtual reality (VR) presents an opportunity to develop novel assessment tools for patients with USN.
We aimed to design and build a VR tool to detect and characterize subtle USN symptoms, and to test the tool on subjects treated with inhibitory repetitive transcranial magnetic stimulation (TMS) of cortical regions associated with USN.
We created three experimental conditions by applying TMS to two distinct regions of cortex associated with visuospatial processing- the superior temporal gyrus (STG) and the supramarginal gyrus (SMG) - and applied sham TMS as a control. We then placed subjects in a virtual reality environment in which they were asked to identify the flowers with lateral asymmetries of flowers distributed across bushes in both hemispaces, with dynamic difficulty adjustment based on each subject's performance. 
We found significant differences in average head yaw between subjects stimulated at the STG and those stimulated at the SMG and marginally significant effects in the average visual axis.
VR technology is becoming more accessible, affordable, and robust, presenting an exciting opportunity to create useful and novel game-like tools. In conjunction with TMS, these tools could be used to study specific, isolated, artificial neurological deficits in healthy subjects, informing the creation of VR-based diagnostic tools for patients with deficits due to acquired brain injury. This study is the first to our knowledge in which artificially generated USN symptoms have been evaluated with a VR task.

The goal was to design, build, and pilot a novel virtual reality task to detect and characterize unilateral spatial neglect, a syndrome affecting 23-46% of acute stroke survivors, expanding the role of virtual reality in the study and management of neurologic disease.

Unilateral spatial neglect (USN) is a syndrome characterized by inattention to or inaction in one side of space and affects between 23-46% of acute stroke ...

A Visuospatial Planning Task Coupled with Eye-Tracker and Electroencephalogram Systems

The planning process, characterized by the capability to formulate an organized plan to reach a goal, is essential for human goal-directed behavior. Since planning is compromised in several neuropsychiatric disorders, the implementation of proper clinical and experimental tests to examine planning is critical. Due to the nature of the deployment of planning, in which several cognitive domains participate, the assessment of planning and the design of behavioral paradigms coupled with neuroimaging methods are current challenges in cognitive neuroscience. A planning task was evaluated in combination with an electroencephalogram (EEG) system and eye movement recordings in 27 healthy adult participants. Planning can be separated into two stages: a mental planning stage in which a sequence of steps is internally represented and an execution stage in which motor action is used to achieve a previously planned goal. Our protocol included a planning task and a control task. The planning task involved solving 36 maze trials, each representing a zoo map. The task had four periods: i) planning, where the subjects were instructed to plan a path to visit the locations of four animals according to a set of rules; ii) maintenance, where the subjects had to retain the planned path in their working memory; iii) execution, where the subjects used eye movements to trace the previously planned path as indicated by the eye-tracker system; and iv) response, where the subjects reported the order of the visited animals. The control task had a similar structure, but the cognitive planning component was removed by modifying the task goal. The spatial and temporal patterns of the EEG revealed that planning induces a gradual and lasting rise in frontal-midline theta activity (FM&#952;) over time. The source of this activity was identified within the prefrontal cortex by source analyses. Our results suggested that the experimental paradigm combining EEG and eye-tracker systems was optimal for evaluating cognitive planning.

The study of cognitive planning combining EEG and eye-tracking systems provides a multimodal approach to investigate the neural mechanisms that mediate cognitive control and goal-directed behavior in humans. Here, we describe a protocol for investigating the role of brain oscillations and eye movements in planning performance.

The planning process, characterized by the capability to formulate an organized plan to reach a goal, is essential for human goal-directed behavior. Since ...