AbstractHistorically, the transformation of sensory inputs into action has been treated as a set of relatively unidirectional processing events: first, processing sensory information, then constructing an internal representation of the world, making a decision about the target of action, and finally executing an action plan. This sequential approach leaves a critical gap in our understanding of how sensorimotor circuits operate in complex visual environments in concert with perceptual and cognitive systems. In the present study, to overcome this gap, we aimed to examine co-dependence between action and perception. Specifically, we examined the relation between action fluency and the sensitivity of perceptual discrimination. We used a dual-task paradigm, in which participants prepared an action (e.g., grasping) with varying difficulty levels of execution, while concurrently performing an orientation change-detection task. We demonstrated that as action became more fluent (i.e., grasping errors decreased), perceptual discrimination performance also improved. Importantly, we also established a casual relation that grasping training prior to discrimination enhanced subsequent perceptual sensitivity. Together, our results clearly showed synergistic and reciprocal connection between perceptual and motor processes. Further understanding of this relation might also contribute to developing a more effective visual acuity training program by combining fluent action for amblyopia or other visual deficits.
Acknowledgments: NSF CAREER Award (BCS 1555006) to J.H.S