Dissociation of perception and motor execution of lower limb in multi-directional movements

Abstract

Abstract Estimating action capability is important for humans to successfully move their bodies. Reachability has been proposed to be an overestimation of motor abilities, by judging the unreachable distance as reachable. Existing literature have mainly investigated the sagittal direction, but multi-directional reachability is unexplored. This study examined the relationship between cognition and movement using the reaching of the lower limbs in multiple directions. Sixteen adults were asked to reach targets projected on the floor in 21 locations (seven directions and three distances) to estimate the reaching time. We found that movement slowed as the direction increased toward the contralateral side, but subjective reaching time did not change with direction. Multiple regression analysis showed that subjective reaching time could be calculated with high accuracy, using mainly the duration from the toe leaving the ground to movement completion. These results suggest that changes in direction may not be perceived precisely by the motor system of the lower limbs, and subjective reaching time was strongly affected by the time after the toe- left the ground. Our findings provide novel insights into the relationship between motor and cognition in multiple directions, which may provide a new strategy for the maximal performance of lower limb movement.