60,063 research outputs found

    Timing and correction of stepping movements with a virtual reality avatar

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    Research into the ability to coordinate one’s movements with external cues has focussed on the use of simple rhythmic, auditory and visual stimuli, or interpersonal coordination with another person. Coordinating movements with a virtual avatar has not been explored, in the context of responses to temporal cues. To determine whether cueing of movements using a virtual avatar is effective, people’s ability to accurately coordinate with the stimuli needs to be investigated. Here we focus on temporal cues, as we know from timing studies that visual cues can be difficult to follow in the timing context. Real stepping movements were mapped onto an avatar using motion capture data. Healthy participants were then motion captured whilst stepping in time with the avatar’s movements, as viewed through a virtual reality headset. The timing of one of the avatar step cycles was accelerated or decelerated by 15% to create a temporal perturbation, for which participants would need to correct to, in order to remain in time. Step onset times of participants relative to the corresponding step-onsets of the avatar were used to measure the timing errors (asynchronies) between them. Participants completed either a visual-only condition, or auditory-visual with footstep sounds included, at two stepping tempo conditions (Fast: 400ms interval, Slow: 800ms interval). Participants’ asynchronies exhibited slow drift in the Visual-Only condition, but became stable in the Auditory-Visual condition. Moreover, we observed a clear corrective response to the phase perturbation in both the fast and slow tempo auditory-visual conditions. We conclude that an avatar’s movements can be used to influence a person’s own motion, but should include relevant auditory cues congruent with the movement to ensure a suitable level of entrainment is achieved. This approach has applications in physiotherapy, where virtual avatars present an opportunity to provide the guidance to assist patients in adhering to prescribed exercises

    Prefrontal cortex activation upon a demanding virtual hand-controlled task: A new frontier for neuroergonomics

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    open9noFunctional near-infrared spectroscopy (fNIRS) is a non-invasive vascular-based functional neuroimaging technology that can assess, simultaneously from multiple cortical areas, concentration changes in oxygenated-deoxygenated hemoglobin at the level of the cortical microcirculation blood vessels. fNIRS, with its high degree of ecological validity and its very limited requirement of physical constraints to subjects, could represent a valid tool for monitoring cortical responses in the research field of neuroergonomics. In virtual reality (VR) real situations can be replicated with greater control than those obtainable in the real world. Therefore, VR is the ideal setting where studies about neuroergonomics applications can be performed. The aim of the present study was to investigate, by a 20-channel fNIRS system, the dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC) in subjects while performing a demanding VR hand-controlled task (HCT). Considering the complexity of the HCT, its execution should require the attentional resources allocation and the integration of different executive functions. The HCT simulates the interaction with a real, remotely-driven, system operating in a critical environment. The hand movements were captured by a high spatial and temporal resolution 3-dimensional (3D) hand-sensing device, the LEAP motion controller, a gesture-based control interface that could be used in VR for tele-operated applications. Fifteen University students were asked to guide, with their right hand/forearm, a virtual ball (VB) over a virtual route (VROU) reproducing a 42 m narrow road including some critical points. The subjects tried to travel as long as possible without making VB fall. The distance traveled by the guided VB was 70.2 ± 37.2 m. The less skilled subjects failed several times in guiding the VB over the VROU. Nevertheless, a bilateral VLPFC activation, in response to the HCT execution, was observed in all the subjects. No correlation was found between the distance traveled by the guided VB and the corresponding cortical activation. These results confirm the suitability of fNIRS technology to objectively evaluate cortical hemodynamic changes occurring in VR environments. Future studies could give a contribution to a better understanding of the cognitive mechanisms underlying human performance either in expert or non-expert operators during the simulation of different demanding/fatiguing activities.openCarrieri, Marika; Petracca, Andrea; Lancia, Stefania; Basso Moro, Sara; Brigadoi, Sabrina; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, ValentinaCarrieri, Marika; Petracca, Andrea; Lancia, Stefania; BASSO MORO, Sara; Brigadoi, Sabrina; Spezialetti, Matteo; Ferrari, Marco; Placidi, Giuseppe; Quaresima, Valentin

    Knowing me, knowing you: perspectives on awareness in autism

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    Purpose: This paper raises important questions from the different perspectives on autism research that arose from a seminar on autism and technology, held as part of an ESRC-funded series on innovative technologies for autism. Design/methodology/approach: The paper focuses on the roles of technology in understanding questions about different perspectives on autism: how do people on the spectrum see neurotypicals (people without autism) and vice versa?; how do we use eye-gaze differently from each other?; how might technology influence what is looked at and how we measure this?; what differences might there be in how people use imitation of others?; and finally, how should we study and treat any differences? Findings: We synthesise common themes from invited talks and responses. The audience discussions highlighted the ways in which we take account of human variation, how we can understand the perspective of another, particularly across third-person and second-person approaches in research, and how researchers and stakeholders engage with each other. Originality/value: We argue that the question of perspectives is important for considering how people with autism and neurotypical people interact in everyday contexts, and how researchers frame their research questions and methods. We propose that stakeholders and researchers can fruitfully engage directly in discussions of research, in ways that benefit both research and practice

    Trunk motion visual feedback during walking improves dynamic balance in older adults: Assessor blinded randomized controlled trial.

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    BACKGROUND: Virtual reality and augmented feedback have become more prevalent as training methods to improve balance. Few reports exist on the benefits of providing trunk motion visual feedback (VFB) during treadmill walking, and most of those reports only describe within session changes. RESEARCH QUESTION: To determine whether trunk motion VFB treadmill walking would improve over-ground balance for older adults with self-reported balance problems. METHODS: 40 adults (75.8 years (SD 6.5)) with self-reported balance difficulties or a history of falling were randomized to a control or experimental group. Everyone walked on a treadmill at a comfortable speed 3×/week for 4 weeks in 2 min bouts separated by a seated rest. The control group was instructed to look at a stationary bulls-eye target while the experimental group also saw a moving cursor superimposed on the stationary bulls-eye that represented VFB of their walking trunk motion. The experimental group was instructed to keep the cursor in the center of the bulls-eye. Somatosensory (monofilaments and joint position testing) and vestibular function (canal specific clinical head impulses) was evaluated prior to intervention. Balance and mobility were tested before and after the intervention using Berg Balance Test, BESTest, mini-BESTest, and Six Minute Walk. RESULTS: There were no significant differences between groups before the intervention. The experimental group significantly improved on the BESTest (p = 0.031) and the mini-BEST (p = 0.019). The control group did not improve significantly on any measure. Individuals with more profound sensory impairments had a larger improvement on dynamic balance subtests of the BESTest. SIGNIFICANCE: Older adults with self-reported balance problems improve their dynamic balance after training using trunk motion VFB treadmill walking. Individuals with worse sensory function may benefit more from trunk motion VFB during walking than individuals with intact sensory function

    De-Roling from Experiences and Identities in Virtual Worlds

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    Within dramatherapy and psychodrama, the term ‘de-roling’ indicates a set of activities that assist the subjects of therapy in ‘disrobing’ themselves from their fictional characters. Starting from the psychological needs and the therapeutic goals that ‘de-roling’ techniques address in dramatherapy and psychodrama, this text provides a broader understanding of procedures and exercises that define and ease transitional experiences across cultural practices such as religious rituals and spatial design. After this introductory section, we propose a tentative answer as to why game studies and virtual world research largely ignored processes of ‘roling’ and ‘de-roling’ that separate the lived experience of role-play from our everyday sense of the self. The concluding sections argue that de-roling techniques are likely to become more relevant, both academically and in terms of their practical applications, with the growing diffusion of virtual technologies in social practices. The relationships we can establish with ourselves and with our surroundings in digital virtual worlds are, we argue, only partially comparable with similar occurrences in pre-digital practices of subjectification. We propose a perspective according to which the accessibility and immersive phenomenological richness of virtual reality technologies are likely to exacerbate the potentially dissociative effects of virtual reality applications. This text constitutes an initial step towards framing specific socio-technical concerns and starting a timely conversation that binds together dramatherapy, psychodrama, game studies, and the design of digital virtual worlds

    The minimum energy expenditure shortest path method

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    This article discusses the addition of an energy parameter to the shortest path execution process; namely, the energy expenditure by a character during execution of the path. Given a simple environment in which a character has the ability to perform actions related to locomotion, such as walking and stair stepping, current techniques execute the shortest path based on the length of the extracted root trajectory. However, actual humans acting in constrained environments do not plan only according to shortest path criterion, they conceptually measure the path that minimizes the amount of energy expenditure. On this basis, it seems that virtual characters should also execute their paths according to the minimization of actual energy expenditure as well. In this article, a simple method that uses a formula for computing vanadium dioxide (VO2VO_2) levels, which is a proxy for the energy expenditure by humans during various activities, is presented. The presented solution could be beneficial in any situation requiring a sophisticated perspective of the path-execution process. Moreover, it can be implemented in almost every path-planning method that has the ability to measure stepping actions or other actions of a virtual character

    Application of serious games to sport, health and exercise

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    Use of interactive entertainment has been exponentially expanded since the last decade. Throughout this 10+ year evolution there has been a concern about turning entertainment properties into serious applications, a.k.a "Serious Games". In this article we present two set of Serious Game applications, an Environment Visualising game which focuses solely on applying serious games to elite Olympic sport and another set of serious games that incorporate an in house developed proprietary input system that can detect most of the human movements which focuses on applying serious games to health and exercise

    Feeling crowded yet?: Crowd simulations for VR

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    With advances in virtual reality technology and its multiple applications, the need for believable, immersive virtual environments is increasing. Even though current computer graphics methods allow us to develop highly realistic virtual worlds, the main element failing to enhance presence is autonomous groups of human inhabitants. A great number of crowd simulation techniques have emerged in the last decade, but critical details in the crowd's movements and appearance do not meet the standards necessary to convince VR participants that they are present in a real crowd. In this paper, we review recent advances in the creation of immersive virtual crowds and discuss areas that require further work to turn these simulations into more fully immersive and believable experiences.Peer ReviewedPostprint (author's final draft

    The Effectiveness of Aquatic Therapy, Robot Assisted Gait Training, and Virtual Reality on Patients with Parkinson\u27s Disease: A Literature Review

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    Background & Purpose: Parkinson’s disease (PD) is a progressive neurodegenerative disorder that affects a person’s central nervous system (CNS) as well as dopamine production. Most cases of PD cause the patient to have postural instability, difficulty with ambulation, as well as a resting tremor. Patients diagnosed with PD show a slow decline in overall function and therefore, need to maintain physical activity in order to plateau PD. Traditionally, patients with PD undergo conventional methods of physical therapy (PT) to help plateau their disease. Our literature review looked into the effectiveness of non-traditional methods such as aquatic therapy, robot-assisted gait training (RAGT), and virtual reality (VR). Methods: We started our search in January 2021, using the PubMed database, and found 7,222 articles. Using the combination of “Parkinson’s disease” with the terms “aquatic therapy”, “robot-assisted gait training”, “virtual reality”, “pathophysiology”, “end-effector”, and “stepping time” and narrowed down our articles to 11. As this is a literature review, we would skim the abstracts and then decide from there whether to read the entire article to use it for our research. Results & Discussion: Aquatic therapy, RAGT, and VR are all beneficial to individuals with PD when looking for balance improvement. Conclusion: More research is needed in aquatic therapy, RAGT, and VR when looking into the effectiveness and benefits for individuals with PD and PT should consider treating patients with PD with non-conventional methods if available.https://digitalcommons.misericordia.edu/research_posters2021/1067/thumbnail.jp
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