An object for an action, the same object for other actions: effects on hand shaping

Abstract

Objects can be grasped in several ways due to their physical properties, the context surrounding the object, and the goal of the grasping agent. The aim of the present study was to investigate whether the prior-to-contact grasping kinematics of the same object vary as a result of different goals of the person grasping it. Subjects were requested to reach toward and grasp a bottle filled with water, and then complete one of the following tasks: (1) Grasp it without performing any subsequent action; (2) Lift and throw it; (3) Pour the water into a container; (4) Place it accurately on a target area; (5) Pass it to another person. We measured the angular excursions at both metacarpal-phalangeal (mcp) and proximal interphalangeal (pip) joints of all digits, and abduction angles of adjacent digit pairs by means of resistive sensors embedded in a glove. The results showed that the presence and the nature of the task to be performed following grasping affect the positioning of the fingers during the reaching phase. We contend that a one-to-one association between a sensory stimulus and a motor response does not capture all the aspects involved in grasping. The theoretical approach within which we frame our discussion considers internal models of anticipatory control which may provide a suitable explanation of our results.

Limb versus Speech Motor Control: A Conceptual Review

“…Obviously, the choice of the first motor act is adapted with respect to the goal of the second movement, enabling a comfortable end state (Rosenbaum et al, 2006). Similar to those daily life observations, experiments with various motion tasks showed that movement parameters like hand shaping, peak aperture, and reaching duration of an initial reaching and grasping submovement are affected in various ways by the movement that follows (Ansuini et al, 2006(Ansuini et al, , 2008Armbrüster & Spijkers, 2006). Throwing or placing an object under high or low accuracy constraints, for instance, affects hand shaping during the approach phase.…”

Interactional leader–follower sensorimotor communication strategies during repetitive joint actions

“…We already showed that the asymmetric allocation of information concerning an action's goal is reflected in the way we perform that action and thus communicate with our partners during motor interactions [14]. Thus, the kinematics of our movements are not resistant to higher-order plans such as the representation we hold of the overall goal of an action [32,33]. During motor interactions, we tend to build a representation of what we think our partner will do based on the information we have and those we are able to infer from his behaviour [34].…”

Understanding intentions from actions: Direct perception, inference, and the roles of mirror and mentalizing systems

“…Importantly, the kinematics of reach--to--grasp actions are modulated even when actions are performed on the same object, but with different intentions. Thus Marteniuk and colleagues (1987) demonstrated differences in the kinematic profiles of actions when the actor's intention was to place an object carefully into a small container, versus into a large box (see Ansuini, Giosa, Turella, Altoè, & Castiello, 2008;Ansuini, Santello, Massaccesi, & Castiello, 2006, for a similar result). Consistent with these results, Schuboe and colleagues (2008) showed kinematic differences between actions towards a bottle depending on whether the intention was to pour or to place the bottle; and a comprehensive set of studies from Becchio and colleagues demonstrated differences in kinematics between cooperative and competitive actions, between social and non--social actions, and between individual and communicative actions (Becchio, Sartori, Bulgheroni, & Castiello, 2008;Georgiou, Becchio, Glover, & Castiello, 2007;Sartori, Becchio, Bara, & Castiello, 2009).…”