Immersive 3D Virtual Reality Cancellation Task for Visual Neglect Assessment: A Pilot Study

Abstract

Background: Unilateral spatial neglect is an attention disorder frequently occurring after a right-hemispheric stroke. Neglect results in a reduction in quality of life and performance in activities of daily living. With current technical improvements in virtual reality (VR) technology, training with stereoscopic head-mounted displays (HMD) has become a promising new approach for the assessment and the rehabilitation of neglect. The focus of this pilot study was to develop and evaluate a simple visual search task in VR for HMD. The VR system was tested regarding feasibility, acceptance, and potential adverse effects in healthy controls and right-hemispheric stroke patients with and without neglect. Methods: The VR system consisted of two main components, a head-mounted display to present the virtual environment, and a hand-held controller for the interaction with the latter. The task followed the rationale of diagnostic paper-pencil cancellation tasks; i.e., the participants were asked to search targets among distractors. However, instead of a two-dimensional setup, the targets and distractors were arranged in three dimensions, in a sphere around the subject inside its field of view. Usability and acceptance of the task, as well as the performance in the latter, were tested in 15 right-hemispheric subacute stroke patients (10 of whom with and five of whom without unilateral spatial neglect; mean age: 67.1 ± 10.5 years) and 35 age-matched healthy controls. Results: System usability and acceptance were rated as high both in stroke patients and healthy controls, close to the maximum score of the questionnaire scale. No relevant adverse effects occurred. There was a high correlation (r = 0.854, p = 0.002) between the Center of Cancellation [an objective neglect measure) calculated from a paperpencil cancellation task (Sensitive Neglect Test (SNT)] and the newly developed VR cancellation task. Conclusion: Overall, the developed visual search task in the tested VR system is feasible, well-accepted, enjoyable, and does not evoke any significant negative effects, both for

Development of a Search Task Using Immersive Virtual Reality: Proof-of-Concept Study

“…The ratings for usability and acceptance of the bird search task were high in both healthy participants and stroke patients with hemispatial neglect. This result is in line with previous findings from studies investigating the acceptance of HMD-VR in elderly [60,61], studies using VR for neglect diagnostics [51], and studies in which a similar VR setup was used to apply audio-visual stimulation in critically ill patients [62].…”

“…To assess acceptance, usability, and participant's perception of the visual search task and of the VR system, 3 questions from the System Usability Scale (SUS) [ 49 ] were used, as previously reported by Gerber et al [ 50 ] and Knobel et al [ 51 ]. The questions were answered using a 5-point Likert-scale, ranging from “fully disagree” to “fully agree.” The mean score across all questions was calculated for each participant.…”

“…The Simulator Sickness Questionnaire (SSQ) [ 52 ] was used to assess side effects such as cybersickness, oculomotor problems, and disorientation [ 53 , 54 ]. In order to reduce the workload of the study participants, a subset of 7 questions from the SSQ was used, as previously reported by Gerber et al [ 50 ] and Knobel et al [ 51 ]. The questions were answered using a 4-point Likert-scale (ie, “None,” “Slight,” “Moderate,” “Severe”).…”

“…Regarding side effects, overall, only slight to none were reported. Furthermore, the nature and intensity of side effects [51,54,62]. In the group of patients with neglect, no severe side effects were reported (only 1 participant reported moderate sweating).…”

Procedural Learning through Action Observation: Preliminary Evidence from Virtual Gardening Activity in Intellectual Disability

“…VR implies the use of a computer-generated simulation of 3D environments, through which the users can experience a full or semi-immersive experience, as if they were in a real context dimension [58,61,62]. Innovative VR devices, including head mounted displays (HMDs) [57,[63][64][65], give the opportunity of taking advantage of a higher level of immersion (i.e., immersive virtual environments (IVEs)) [57], which is effective for enhancing motor and cognitive skills in healthy [63,65,66] and clinical populations [67][68][69]. Conversely, semiimmersive VR, due to the lack of HDMs, does not guarantee a full immersion but favors the interaction among participants, promoting group therapies [61].…”