An augmented reality home-training system based on the mirror training and imagery approach

Trojan J, Diers M, Fuchs X, et al. An augmented reality home-training system based on the mirror training and imagery approach. Behavior Research Methods. 2013;46(3):634-640

Treatment of phantom limb pain (PLP) based on augmented reality and gaming controlled by myoelectric pattern recognition: a case study of a chronic PLP patient

A variety of treatments have been historically used to alleviate phantom limb pain (PLP) with varying efficacy. Recently, virtual reality (VR) has been employed as a more sophisticated mirror therapy. Despite the advantages of VR over a conventional mirror, this approach has retained the use of the contralateral limb and is therefore restricted to unilateral amputees. Moreover, this strategy disregards the actual effort made by the patient to produce phantom motions. In this work, we investigate a treatment in which the virtual limb responds directly to myoelectric activity at the stump, while the illusion of a restored limb is enhanced through augmented reality (AR). Further, phantom motions are facilitated and encouraged through gaming. The proposed set of technologies was administered to a chronic PLP patient who has shown resistance to a variety of treatments (including mirror therapy) for 48 years. Individual and simultaneous phantom movements were predicted using myoelectric pattern recognition and were then used as input for VR and AR environments, as well as for a racing game. The sustained level of pain reported by the patient was gradually reduced to complete pain-free periods. The phantom posture initially reported as a strongly closed fist was gradually relaxed, interestingly resembling the neutral posture displayed by the virtual limb. The patient acquired the ability to freely move his phantom limb, and a telescopic effect was observed where the position of the phantom hand was restored to the anatomically correct distance. More importantly, the effect of the interventions was positively and noticeably perceived by the patient and his relatives. Despite the limitation of a single case study, the successful results of the proposed system in a patient for whom other medical and non-medical treatments have been ineffective justifies and motivates further investigation in a wider study

Clinical Trial of the Virtual Integration Environment to Treat Phantom Limb Pain With Upper Extremity Amputation

Background: Phantom limb pain (PLP) is commonly seen following upper extremity (UE) amputation. Use of both mirror therapy, which utilizes limb reflection in a mirror, and virtual reality therapy, which utilizes computer limb simulation, has been used to relieve PLP. We explored whether the Virtual Integration Environment (VIE), a virtual reality UE simulator, could be used as a therapy device to effectively treat PLP in individuals with UE amputation.Methods: Participants with UE amputation and PLP were recruited at Walter Reed National Military Medical Center (WRNMMC) and instructed to follow the limb movements of a virtual avatar within the VIE system across a series of study sessions. At the end of each session, participants drove virtual avatar limb movements during a period of “free-play” utilizing surface electromyography recordings collected from their residual limbs. PLP and phantom limb sensations were assessed at baseline and following each session using the Visual Analog Scale (VAS) and Short Form McGill Pain Questionnaire (SF-MPQ), respectively. In addition, both measures were used to assess residual limb pain (RLP) at baseline and at each study session. In total, 14 male, active duty military personnel were recruited for the study.Results: Of the 14 individuals recruited to the study, nine reported PLP at the time of screening. Eight of these individuals completed the study, while one withdrew after three sessions and thus is not included in the final analysis. Five of these eight individuals noted RLP at baseline. Participants completed an average of 18, 30-min sessions with the VIE leading to a significant reduction in PLP in seven of the eight (88%) affected limbs and a reduction in RLP in four of the five (80%) affected limbs. The same user reported an increase in PLP and RLP across sessions. All participants who denied RLP at baseline (n = 3) continued to deny RLP at each study session.Conclusions: Success with the VIE system confirms its application as a non-invasive and low-cost therapy option for PLP and phantom limb symptoms for individuals with upper limb loss

Jahresbericht 2010 / Institut für Angewandte Informatik (KIT Scientific Reports ; 7601)

Das Institut für Angewandte Informatik (IAI) ist eine Organisationseinheit des Karlsruher Instituts für Technologie (KIT), Universität des Landes Baden-Württemberg und nationales Forschungszentrum in der Helmholtz-Gemeinschaft. Das Institut betreibt Forschung und Entwicklung auf dem Gebiet innovativer, anwendungsorientierter Informations-, Automatisierungs- und Systemtechnik

Ein neues Konzept zur Sensorik und Steuerung einer aktiven Hybrid-Orthese für die obere Extremität

Für die Nutzung der aktiven Hybrid-Orthese für die obere Extremität wird in dieser Dissertationsschrift ein neues Konzept zur Sensorik und Steuerung vorgestellt. Die Grundidee besteht darin, neue, beziehungsweise modifizierte, Sensoren zur Steuerung der aktiven Hybrid-Orthese zu entwickeln. Mittels der entwickelten Sensoren wird eine neue Steuerung und ein neues Konzept zur Steuerung der aktive Hybrid-Orthese entwickelt und anschließend evaluiert

Measuring prefrontal cortex response to virtual reality exposure therapy in freely moving participants

Virtual Reality Exposure Therapy has demonstrated efficacy in the treatment of phobias; yet little is known about its underlying neural mechanisms. Neuroimaging studies have demonstrated that both traditional exposure therapy and virtual reality exposure therapy normalise brain activity within a prefrontal - amygdalar fear circuit after the treatment. However, the previous studies employed technologies that perhaps impact on ecological validity and naturalness of experience. Moreover, there are no studies investigating what is happening in the brain within a virtual reality session. This PhD takes a multidisciplinary approach and draws upon research areas of cognitive neuroscience, neuropsychology, and virtual reality. The approach is twofold - developmental and experimental. A key methodological objective was to maximise ecological validity by allowing freedom of movement and sight of one’s own body. This was approached by combining wearable fNIRS within Immersive Projection Technology (IPT). The stimulus was adapted from a classic VR experiment - Pit Room. The scope of this PhD includes three experiments. The first pilot experiment tested the potential of combining the wearable Functional Near-Infrared Spectroscopy (fNIRS) device – NIRSport, with virtual reality (VR) display - CAVE-like Immersive Projection Technology (IPT) system – Octave. The aim was to test the feasibility of the protocol in terms of the design, integration of technology, and signal to noise ratio in the Pit Room study, which involved measuring brain response during exposure to heights in virtual reality. The study demonstrated that brain activity could be measured in IPT without a significant signal interference. Although there was no significant change in brain activity during exposure to virtual heights, the study found trends toward increased HbO in the prefrontal cortex. The second study investigated the brain activity indicative of fear inhibition and cognitive reappraisal within a single session of VRET in healthy controls. The heart rate was also measured as an indicator of emotional arousal (fear response) during the VRET session. 27 healthy volunteers were exposed to heights in virtual reality. Changes in oxygenated haemoglobin concentration in the prefrontal cortex were measured in three blocks using a wireless fNIRS, and heart rate was measured using a wireless psychophysiological monitor. Results revealed increased HbO concentration in the DLPFC and MPFC during exposure to the fear-evoking VR, consistent with fear inhibition and cognitive reappraisal measured in previous neuroimaging studies that had not used VR. Within-session brain activity was measured at much higher temporal resolution than in previous studies. Consistent with previous studies, a trend showed an increase of brain activity in the DLPFC indicative of cognitive reappraisal at the beginning of the session. Then additionally the MPFC was activated consistent with fear inhibition. The heart rate showed a trend towards a gradual decrease within a session. The aim of the third study was to investigate the neural basis of VRET in an acrophobic population. In particular, the study focused on measuring functional brain activity associated with both within- and between-session learning. Psychophysiological monitoring was also employed to measure levels of emotional arousal within- and between sessions. 13 acrophobic volunteers took part in three-session VRET for a fear of heights. Changes in HbO in the prefrontal cortex were measured in three blocks to investigate within–session brain activity and across three sessions to investigate between-session inhibitory learning. Results demonstrated that phobic participants have decreased activity in the DLPFC and MPFC at the beginning, however, after three sessions of VRET, activity in these brain areas increased towards normal (measured in healthy controls). Although there was no within-session learning during the first and second session, the study found a significant increase in the DLPFC at the beginning of a session. During the second block, additionally, the MPFC was activated. The magnitude of brain activity in those regions was negatively correlated with the initial level of acrophobia. Due to the technical difficulties, no significant results were found in psychophysiological measures. However, subjective fear ratings decreased significantly within- and between sessions. Moreover, participants who felt more present demonstrated stronger results in brain activity at the end of VRET. This is the first project that investigated the neural correlates of fear inhibition and inhibitory learning by combining a VR display in which people can move around and see their body, with wearable neural imaging that gave a reasonable compromise between spatial and temporal resolution. This project has an application in widening access to immersive neuroimaging across understanding, diagnosis, assessment, and treatment of, a range of mental disorders such as phobia, anxiety or post-traumatic stress disorder. An application that is receiving an interest in the clinical community is repeatable, direct and quantifiable assessment within clinics, to diagnose, steer treatment and measure treatment outcome