Table 4.

Identification of problems and proposed recommendations or using technology to perform virtual tasks by people with dementia.

Technology, Identified problems		Solution
LMa
	Grabbing/moving technology needlessly	Design a setup where the LM is fixed and not graspable (ie, a 3D printed container or embedded onto the tabletop surface).
	Confusing virtual objects (spheres) with the joints of the virtual hand	Use identifiable virtual objects and representations of the hand with higher realism.
Tablet
	Moving the whole tablet involuntarily	Secure the tablet on a table or fixed structure such that patients do not need to hold it and can interact with its touch screen.
	Triggering undesired touch inputs	Deactivate multi-touch and disable system buttons.
ARb
	Interaction with physical elements	Ergonomic design with affordances consistent with the task at hand can enhance performance.
	Tracking problems	The most common tracking problems are related to (1) shadows, (2) markers out of the camera’s field-of-view, or (3) projection of virtual elements on markers. Solutions include using a room without direct sunlight and controlled light conditions; using lower contrast virtual elements that diminish interference of projecting on markers; and using a setup with clearly defined interaction boundaries.
Mouse
	Buttons not salient	Select a computer mouse that visually clearly identifies where those buttons are. A large colored sticker or paint on a button can also be used to improve its saliency.
	Too many buttons	Most modern computer mice consist of 3 buttons and a scroll wheel. Choose a one-button mouse (ie, Apple mouse). Disabling or mapping all mouse buttons to the same functionality will minimize the impact of choosing the wrong button.
	Mouse cursor (and other elements) too small	Increase the size of the mouse cursor and other virtual elements to enhance performance.
HMDc with controllers
	Too many buttons in handheld controls	Users only see a virtual representation of the controls in the HMD. Minimum button input should be considered while the remaining buttons are disabled or mapped to the same function.
	Hitting controls against each other	Use only one control to interact with the virtual content when possible. Alternatively, replace the controllers with an LM.
HMD with LM
	Lack of haptic feedback	Complement with alternative channels to convey haptic feedback (ie, auditory or visual).
	Cybersickness and balance issues	People with disabilities need to be assessed for balance, and seating setups should be considered. Safety harnesses or other safety measures should be considered when standing.
HMD
	Discomfort because of the device’s heat	Use in a properly ventilated room. In case of discomfort, divide the session into multiple shorter intervals.
	Cybersickness	Virtual environments should be designed to minimize optic flow, and incongruency between physical and virtual motion should be minimized. It can be achieved by reducing forward motion and rotations as well as using simpler environments with fewer visual elements.

^aLM: leap motion.

^bAR: augmented reality.

^cHMD: head-mounted display.