Neural dynamics of hand pre-shaping during prehension

The reach-to-grasp movement exhibits both parallel and serial combinations of tightly scheduled movement components. Among the movement components are a free movement phase involving transport and pre-shaping of the hand, and in-contact phases, involving grasping, lifting, and manipulation of objects with appropriate forces. Several factors are known to influence the shape of the hand (hand preshaping) during a reach-to-grasp movement, including the initial aperture of the fingers, object size, or movement speed. Moreover, the spatiotemporal specification of the parameters for hand pre-shaping may evolve gradually during the reach-to-grasp movement. In this paper we simulate three computational models of coordination between hand transport and hand preshaping under different initial finger aperture conditions to investigate the spatiotemporal dynamics of hand preshaping.