Digital Haptics Improve Speed of Visual Search Performance in a Dual-Task Setting

Abstract

Dashboard-mounted touchscreen tablets are now common in vehicles. Screen/phone use in cars likely shifts drivers’ attention away from the road and contributes to risk of accidents. Nevertheless, vision is subject to multisensory influences from other senses. Haptics may help maintain or even increase visual attention to the road, while still allowing for reliable dashboard control. Here, we provide a proof-of-concept for the effectiveness of digital haptic technologies (hereafter digital haptics), which use ultrasonic vibrations on a tablet screen to render haptic perceptions. Healthy human participants (N = 25) completed a divided-attention paradigm. The primary task was a centrally-presented visual conjunction search task, and the secondary task entailed control of laterally-presented sliders on the tablet. Sliders were vertical, horizontal or circular and were presented visually, haptically, or visuo-haptically. We reasoned that the primary task would be performed best when the secondary task was haptic-only. Reaction times (RTs) on the visual search task were fastest when the tablet task was haptic-only. This was not due to a speed-accuracy trade-off. While precision with the tablet task was lowest when haptic-only, such can likely be readily trained. These results provide the first quantitative support for introducing digital haptics into vehicle and similar contexts.