An adaptive strategy for an immersive visuo-haptic attention training game

Abstract

Attention training using virtual environments is a promising way to treat mental disorders such as attention-deficit hyperactivity disorder (ADHD). Interactive haptic tasks combined with immersive visual display provide a potential solution for attention modulation and training. In this paper, we introduced a visuo-haptic game consisting of stimulus-response tasks using fingertip pressure control with immersive visual display using the Oculus Rift. Users were required to press a force sensor using either the index or middle finger from either hand. In each trial, users needed to maintain a constant force with an expected tolerance within an allowable response time. An adaptive strategy was proposed to tune the difficulty level of the task to match the force control skill of the user, which may produce an optimal success rate in each trial to maintain users’ interest and keep them motivated. Furthermore, a randomized algorithm was adopted to vary the target fingertip, target force magnitude and target tolerance between adjacent trials, which was designed to avoid the boring repetition and thus to keep the users’ curiosity on the task. Experimental results on six participants show that the proposed strategy was able to obtain different expected success rates, i.e. either 79.4% or 50%.