Age-related Facilitation of Bimanual Finger Behaviors by Haptic Augmentation

Abstract

Proficient use of multiple fingers across both hands to manipulate objects empowers our daily interactions with the world. Gaining dexterity in performing delicate tasks with both hands can take weeks to years to master. The goal of this study is to understand if simple mechanical abstraction could improve performance on bimanual response time to visual stimuli, using index fingers and thumbs. A plate placed over the buttons was introduced to induce a new conceptualization of the task, where instead of pressing buttons, the subjects were rocking a plate over them. We observed improved performance in bimanual actions but not in unilateral actions. In the group of middle-aged individuals, synchronous bimanual responses were enhanced with the use of this mechanical augmentation. This effect remained even after removing the plate. Conversely, within a group of younger adults, there was no observed effect. We believe that highly similar afferent sensory signals from the fingers of both hands change the motor control strategy. This work lays the groundwork for further research into understanding the rich variety of multi-fingered bimanual behaviors in both abstract and practical settings.