JMIR Publications

ABSTRACT

Background:

Orientation deficits are among the most devastating consequences of early dementia. Digital navigation devices may help overcome these deficits, if they are adaptable to the user’s needs, i.e. provide situation aware, proactive navigation assistance. To fulfill this task, systems need to automatically detect spatial disorientation from sensor data in real-time. Ideally, this would require field studies consisting of real-world navigation. However, such field studies can be challenging, and are not guaranteed to cover sufficient instances of disorientation due to the large variability of real-world settings and lack of control over the environment.

Objective:

Extending a foregoing field study, here we aimed at evaluating the feasibility of using a sophisticated virtual reality (VR) setup, which allows a more controlled observation of disorientation states and accompanying behavioral and vital parameters in healthy older people and people with dementia (PwD).

Methods:

In this feasibility study, we describe the experimental design and pilot outcomes of an ongoing study aimed at investigating the effect of disorientation on gait and selected vital features in a virtual laboratory. We transferred a real-world navigation task to a treadmill-based virtual system for gait analysis. Disorientation was induced by deliberately manipulating landmarks in the VR projection. Associated responses in motion behavior and vital parameters were recorded by sensors. Primary outcomes descriptively summarized are variations in motion and vital parameters, frequency of disorientation and questionnaire-derived usability estimates (immersion and perceived control of the gait system) for our population of interest. Included so far are 2 (1 female) healthy older participants (Age: mean = 68.5, SD = 3.5; MMSE: mean = 28.5, SD = 0.7) and 1 PwD (male, age = 79, MMSE = 26). Recruitment is currently ongoing aiming at n = 30 older participants and n = 20 PwD.

Results:

All 3 participants could complete the experiment. The patients’ route was adapted by shortening it relative to the original route. An average of 28 instances of disorientation for the healthy older participants and 12 instances for the patient was observed. Questionnaire outcomes suggest that participants experienced an above-average level of immersion; 4.7 for presence, 5.8 for involvement and 5.5 for realism of 7 possible points, indicating overall a good ability to cope with the experiment. Variations were also observed in motion and vital parameters.

Conclusions:

This study presents the protocol and first feasibility outcomes of a study aimed at investigating the viability of using a sophisticated VR setup, based on an earlier real-world navigation study, to study spatial disorientation among healthy older people and PwD. Preliminary descriptive evaluation of the outcome measures gives confidence to the notion that our setup can be used to assess motion and physiological markers of disorientation even in people with cognitive decline. Clinical Trial: ClinicalTrials.gov; https://clinicaltrials.gov/ct2/show/NCT04134806