Using augmented reality to assess spatial neglect: The Free Exploration Test (FET).

BACKGROUND: To capture the distortion of exploratory activity typical of patients with spatial neglect, traditional diagnostic methods and new virtual reality applications use confined workspaces that limit patients' exploration behavior to a predefined area. Our aim was to overcome these limitations and enable the recording of patients' biased activity in real, unconfined space. METHODS: We developed the Free Exploration Test (FET) based on augmented reality technology. Using a live stream via the back camera on a tablet, patients search for a (non-existent) virtual target in their environment, while their exploration movements are recorded for 30 s. We tested 20 neglect patients and 20 healthy participants and compared the performance of the FET with traditional neglect tests. RESULTS: In contrast to controls, neglect patients exhibited a significant rightward bias in exploratory movements. The FET had a high discriminative power (area under the curve = 0.89) and correlated positively with traditional tests of spatial neglect (Letter Cancellation, Bells Test, Copying Task, Line Bisection). An optimal cut-off point of the averaged bias of exploratory activity was at 9.0° on the right; it distinguished neglect patients from controls with 85% sensitivity. DISCUSSION: FET offers time-efficient (execution time: ∼3 min), easy-to-apply, and gamified assessment of free exploratory activity. It supplements traditional neglect tests, providing unrestricted recording of exploration in the real, unconfined space surrounding the patient.

Spatial Neglect Therapy With the Augmented Reality App "Negami" for Active Exploration Training: A Randomized Controlled Trial on 20 Stroke Patients With Spatial Neglect.

OBJECTIVE: To investigate the efficacy of the augmented reality (AR) app "Negami" as an active exploration training for the treatment of spatial neglect. Improvements of the ipsilesional attention and orientation bias (and resulting contralesional neglect) will be examined in stroke patients with spatial neglect and compared with a control group. DESIGN: Randomized controlled trial with an experimental Negami group, consisting of patients with spatial neglect, and a group of neglect patients receiving standard neglect therapy. SETTING: Three rehabilitation hospitals. PARTICIPANTS: Twenty right hemispheric stroke patients with spatial neglect (N=20). INTERVENTION: Over a period of 2 weeks, both groups received 5 training sessions per week (à 25 minutes). Neglect behavior was assessed weekly over a 5-week period, with the Negami therapy group receiving a second follow-up assessment at 1-to-2-month intervals after completion of training. MAIN OUTCOME MEASURES: Letter Cancellation, Bells Test, Copying Task, Line Bisection Task, and a self-developed "Exploration Test". RESULTS: Both groups improved significantly. While the Negami therapy group improved in 4 of 5 neglect tests used, the standard therapy group improved in only 1 of these tests. We observed significantly better improvement in the Negami group already after the first week of training. This difference was also significant after the end of the training as well as 1 week after the end of training and remained stable 1-2 months after the end of treatment. CONCLUSION: Negami can be used as an effective alternative or addition to current standard neglect therapy, and may even be superior to it.

Negami: An Augmented Reality App for the Treatment of Spatial Neglect After Stroke.

BACKGROUND: A widely applied and effective rehabilitation method for patients experiencing spatial neglect after a stroke is "visual exploration training." Patients improve their ipsilesional bias of attention and orientation by training exploration movements and search strategies toward the contralesional side of space. In this context, gamification can have a positive influence on motivation for treatment and thus on the success of treatment. In contrast to virtual reality applications, treatment enhancements through augmented reality (AR) have not yet been investigated, although they offer some advantages over virtual reality. OBJECTIVE: This study aimed to develop an AR-based app (Negami) for the treatment of spatial neglect that combines visual exploration training with active, contralesionally oriented rotation of the eyes, head, and trunk. METHODS: The app inserts a virtual element (origami bird) into the real space surrounding the patient, which the patient explores with the camera of a tablet. Subjective reports from healthy elderly participants (n=10) and patients with spatial neglect after stroke (n=10) who trained with the new Negami app were analyzed. Usability, side effects, and game experience were assessed by various questionnaires. RESULTS: Training at the highest defined difficulty level was perceived as differently challenging but not as frustrating by the group of healthy elderly participants. The app was rated with high usability, hardly any side effects, high motivation, and entertainment. The group of patients with spatial neglect after stroke consistently evaluated the app positively on the dimensions of motivation, satisfaction, and fun. CONCLUSIONS: The Negami app represents a promising extension by adding AR to traditional exploration training for spatial neglect. Through participants' natural interaction with the physical surrounding environment during playful tasks, side effects as symptoms of cybersickness are minimized and patients' motivation appeared to markedly increase. The use of AR in cognitive rehabilitation programs and the treatment of spatial neglect seems promising and should receive further investigation.