The Cleveland Clinic Virtual Reality Shopping platform combines state-of-the-art virtual reality content with an omnidirectional treadmill to objectively quantify instrumental activities of daily living. A novel aspect of this system is addressing the locomotion problem. Typically, with VR applications, you have a disconnect between visual information and vestibular information, which results in motion sickness.
Here, by combining virtual reality with an omnidirectional treadmill, we have congruent visual and vestibular information, which eliminates motion sickness. A decline in the performance of instrumental activities of daily living has been shown to be a prodromal marker for Parkinson's and Alzheimer's disease. By developing an objective quantitative method of evaluating IADLs, we can potentially have earlier diagnosis and better treatment of these diseases.
Demonstrating the procedure today will be Morgan McGrath, a doctoral candidate from my lab, and Anson Rosenfeldt, the physical therapist from my lab, will be demonstrating the CC-VRS task. Turn on each VR device and look for a green indicator light. Calibrate the boundaries and orientation of the virtual space by selecting Room Setup in the Steam VR menu.
Follow the on-screen prompts using the hand controllers while walking around the boundaries of the virtual space. Next, power on the omnidirectional treadmill using the green power button on the attached foot pedal. Launch the Infinadeck software on the computer.
Use the Select User Tracker function in the application and identify the waist tracker as the appropriate tracking device. Center this tracker on the Infinadeck surface. Use the Set Center Point function to calibrate the middle of the treadmill platform.
Set the waist tracker on the ring and use the Set Ring Height to calibrate the height of the ring. After calibration, fit a full body harness to the user. Fix the left and right-foot trackers to the feet of the user by zip ties around the shoelaces.
Screw the waist tracker onto the specially designed waist belt and adjust the belt until the tracker sits in the middle of the user's lumbar region. Place the left and right-hand controllers and tighten the straps until secure and comfortable. Clip the user's harness into a ceiling-mounted cable above the center of the omnidirectional treadmill to prevent falls and increase the level of comfort for the user without impeding natural gait.
Allow the user to walk and turn on the omnidirectional treadmill. Explain the importance of the waist tracker position relative to the center of the treadmill platform and encourage the user to get comfortable walking around the outer edges of the treadmill boundary while holding the handrail for support. Disengage the treadmill via the application to continue with user preparation.
With the user standing on the stationary treadmill, place the headset on the user's head and assist with adjustments, such as the rear stability knob, top weight-bearing strap, and interpupillary distance slider. Make sure that the fit is comfortable and the display is clear. Ensure the headset-mounted speakers are positioned over the ears and set to an appropriate volume level.
Instruct the user to stand near the center of the omnidirectional treadmill platform and click Start on the application to reengage the treadmill. Launch the CC-VRS application and perform a brief tutorial prior to the Basic and Complex CC-VRS to ensure an understanding of the requirements. Select Comprehensive Tutorial to load a small practice environment.
Activate the shopping list by raising the left hand and holding the A or B button on the controller. Close the shopping list by releasing the A or B button. Select items from the shelves using the controller triggers, then place items into the grocery cart using the controller triggers, then perform a price comparison task for sale items by choosing the most cost effective option.
Avoid obstacles in the store, including spills on the floor and narrowed aisle ways that are caused by the placement of other shoppers or carts along the path. Execute a delayed verbal recall of five words presented via an auditory announcement at the start of the scenario.Pasta.Milk.Butter. Each user completes one basic and one complex shopping scenario.
The basic scenario requires following the route and selecting items from the shopping list. To launch the basic scenario, select Basic Scenario from the drop-down list and path length and the number of list items. In the complex scenario, the user is provided a list of different grocery items while following the identical route through the store, but additional cognitive and motor demands are introduced.
To launch the complex scenario, select Complex Scenario from the drop-down list and choose the path length and number of list items. At the completion of a scenario, summary metrics are displayed for the clinician to view. A participant with Parkinson's disease was assessed using the CC-VRS platform and the navigational path and walking velocity were recorded as they completed the task.
Walking speed over the course of the trial and the number of corresponding list activations are shown. Inspection of the performance of young adults in CC-VRS indicated that they had fewer overall stops and could simultaneously walk and view the list. Conversely, the patients with Parkinson's disease had more stops and each corresponded to a list view, suggesting they were unable to effectively dual-task.
Results of the simulator sickness questionnaire after the CC-VRS indicated that most patients endorsed mild symptoms at baseline with symptoms somewhat elevated immediately after the CC-VRS. The symptoms returned to baseline levels within 30 minutes of completing the platform, suggesting that coupling VR content with an omnidirectional treadmill is feasible. The CC-VRS platform could be used to rehabilitate patients with neurological disease.
We can safely immerse them in a real-world environment and train them on these tasks that are important for daily activities. The CC-VRS is truly scalable and immersive. The objective quantification of instrumental activities of daily living will result in earlier diagnosis of Parkinson's and Alzheimer's disease and better treatments of these diseases.
