Examining Dual-Task Interactions Using a Novel Virtual Reality-Based Simon Task

Abstract

Maintaining balance while performing secondary tasks is essential for daily life. The interplay between motor control and cognitive processes during dual tasks remains equivocal, characterized by mixed findings across studies. This pilot study implements a novel adaptation of the Simon task in virtual reality (VR) to better understand cognitive–motor interactions by observing both postural and cognitive performance under single- and dual-task conditions. Participants (n = 10) stood on a motorized sway-referenced force plate, maintaining balance with or without a secondary task. The secondary tasks consisted of a VR-based Simon task performed either using a joystick controller or by reach and point. Results showed dual-task costs to postural control, with significant increases in center of pressure sway area during the reaching task. Cognitive conflict further increased postural sway under the most demanding condition, when participants performed reaching on the sway-referenced surface. Cognitive performance was also sensitive to task demands, with response times slower on the sway-referenced surface and during pointing, while accuracy was lower during pointing. This suggests that increasing combined task demands can affect both postural and cognitive performance. Together, these preliminary findings are compatible with the central capacity model and contribute to the body of evidence of cognitive penetrability in higher-level postural control processes. Importantly, the VR Simon task provides a simple novel paradigm that can be used to further investigate cognitive–motor interactions during postural control.