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...

<ol>
	<li>Appelros, P., Karlsson, G. M., Seiger, A., Nydevik, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neglect+and+anosognosia+after+first-ever+stroke:+incidence+and+relationship+to+disability.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemispatial+neglect+subtypes,+neuroanatomy,+and+disability.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+neglect+as+a+predictor+of+functional+outcome+one+year+after+stroke.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+neglect+on+functional+outcome+after+stroke&#8211;a+review+of+methodological+issues+and+recent+research+findings.">Impact of neglect on functional outcome after stroke&#8211;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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prism+adaptation+therapy+enhances+rehabilitation+of+stroke+patients+with+unilateral+spatial+neglect:+a+randomized,+controlled+trial.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+effects+of+prism+adaptation+on+chronic+neglect+after+stroke.">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://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Rehabilitation interventions for unilateral neglect after stroke: a systematic review from 1997 through 2012. , (2013).</li><li>Rossetti, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prism+adaptation+to+a+rightward+optical+deviation+rehabilitates+left+hemispatial+neglect.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prism+adaptation+for+spatial+neglect+after+stroke:+translational+practice+gaps.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Don't+neglect+'neglect'-an+update+on+post+stroke+neglect.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adaptation+to+virtual+prisms+and+its+relevance+for+neglect+rehabilitation:+a+single-blind+dose-response+study+with+healthy+participants.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prism+adaptation+effect+on+neural+activity+and+spatial+neglect+depend+on+brain+lesion+site.">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/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generalization+of+prism+adaptation.">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://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Encyclopedia of Clinical Neuropsychology. , 928 (2011).</li><li>Kim, W. S., Paik, N. J., Cho, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> 2017 International Conference on Virtual Rehabilitation (ICVR). , 1-2 (2017).</li><li>Munafo, J., Diedrick, M., Stoffregen, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+virtual+reality+head-mounted+display+Oculus+Rift+induces+motion+sickness+and+is+sexist+in+its+effects.">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><li>Merhi, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Proceedings of the Human Factors and Ergonomics Society Annual Meeting. , 2618-2622 (2018).</li><li>Duh, H. B. L., Parker, D. E., Furness, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Proceedings of 9th International Conference on Human-Computer Interaction. , 5-10 (2018).</li><li>Prothero, J. D., Draper, M. H., Parker, D., Wells, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+an+independent+visual+background+to+reduce+simulator+side-effects.">The use of an independent visual background to reduce simulator side-effects.</a> Aviation, Space, and Environmental Medicine. 70, 277-283 (1999).</li></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 border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<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 ...

Our experimental protocol can address whether prism adaptation therapy is effective for patients with hemispatial neglect and whether our virtual prism adaptation therapy system promotes spatial realignment and cortical activation. Virtual prism adaptation therapy was developed to be less costly, quicker to set up, and easier to adjust than conventional prism adaptation. This technique can be used to replace conventional prism therapy in patients with hemispatial neglect because it can mimic the effects of conventional prism adaptation.This method suggests a potential for using virtual reality for stroke therapy and may give insight into hemispatial neglect rehabilitation within the virtual rehabilitation field. Although the system is based on a virtual reality gaming engine and therefore is easily used. Be sure to take care with preparation.For functional near infrared spectroscopy measurement setup, have the participant sit in a chair with a straight back and confirm that the participant's hand will not hit the table when reaching out. Next, select the appropriate functional near infrared spectroscopy size according to the participant's head circumference and place the cap on the head of the participant so that the vertex 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.Use conductive gel to improve the gain from the light source if critical before inserting the optode and place the retaining cap on the participant. To set up the software, run the functional near infrared spectroscopy system software and load the neglect montage. With the montage displayed on the screen, set 15 sources and 24 detectors according to the montage and click calibrate.To calibrate the virtual prism adaptation therapy system, first mount the virtual reality head mounted display on over the functional near infrared spectroscopy cap taking care to avoid disturbing the cap. When the display is in place, open the virtual prism adaptation therapy software and enter the participant's information. Click start and confirm the visualization of the virtual hand in the display.Initiate the two-step calibration and instruct the participant to watch the red cross mark in the center of the screen. Then press the R key to calibrate the screen. Instruct the participant to point to the target with the right hand.Then press the O key to calibrate the hand position. Sufficient space should be provided for calibration in the hand range and the hand should not be stretched too far to set the target position. At the end of the calibration, confirm the participant's readiness to start the experiment and start the system without the prism mode.Click the start key to initiate an experiment with four phases simultaneously with functional near infrared spectroscopy recording and instruct the participant to point or click with their right index finger within three seconds of the appropriate icon appearing or to rest. In the virtual prism adaptation mode, the set deviation angle results in a virtual hand deviation. The green hand is the actual hand recognized position which is not shown to the user.The blue hands are deviated hands shown to the user. In deviation mode, the user's hand extends in the left direction in order to keep the user's hand more and more close to the target. For the clicking block, instruct the participant to press the push button.Each phase will consist of blocks for pointing, clicking, or resting. In this representative graph, the pointing error for four healthy participants is shown with the average of the median value from 10 trials in the subphase of each pointing task lasting 30 seconds. Here, the pointing error for each subject is presented demonstrating an adaptation during the virtual prism adaptation therapy phases and the post prismatic adaptation.Use screen calibration to place the virtual space in front of the user's visual range and use target distance calibration to place the target within the reach of the user. We have studied healthy adult volunteers, but the technology could be used with clinical patients. In addition, comparison of the data with real prism classes could be meaningful.

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6.5K visualizações.  Delvine Inc.. Nosso protocolo experimental pode abordar se a terapia de adaptação do prisma é eficaz para pacientes com negligência hemisespacial e se nosso sistema de terapia de adaptação de prisma virtual promove realinhamento espacial e ativação cortical. A terapia de adaptação do prisma virtual foi desenvolvida para ser menos cara, mais rápida de configurar e mais fácil de ajustar do que a adaptação convencional do prisma. Esta técnica pode ser usada para substituir a terapia convenciona...