Contributions of Gait and Trunk Movements to Prehension: Perspectives from World- and Body-Centered Coordinates

Abstract

The present paper reviews a series of prehension experiments recently conducted at Simon Fraser University's Human Motor Systems Laboratory, and attempts to place them into the larger context of multi-segmental control theory. Two related lines of experiments are reported: (a) experiments involving prehension during walking, and (b) experiments involving trunk-assisted reaching. Three-dimensional analyses of movements were performed via both world-and body-centered coordinates. Our results are supportive of the idea that both types of tasks are carried out using task-specific synergies. Furthermore, we assert that the actions of these synergies are comprised of variable contributions of different movement systems and result in smooth, world-centered end-point trajectories. We show evidence that this “motor equivalence” is the result of increasing the complexity of a given task. Finally, the implications of the present findings on prevailing motor control theory are discussed in terms of the theoretical mechanisms underlying the coordination of the transport and grasp components of prehension.

Coordinating degrees of freedom during interceptive actions in children

“…Trunk contribution to the reaching movement was examined using a methodology first reported by Marteniuk and colleagues (Marteniuk et al 2000;Marteniuk and Bertram 2001), which involved calculating the wrist coordinates from both world-centered and body-centered Significant differences between the two factors, condition and frame of reference, after post hoc analysis; where two conditions have the same superscript there was no significant difference for that variable frames of reference. This analysis revealed that children exhibited a different coordination between the trunk and arm in the three reach and grasp conditions.…”

“…With adults participants, Marteniuk and colleagues (Marteniuk et al 2000;Marteniuk and Bertram 2001) demonstrated that the amount of trunk flexion and rotation varied according to whether they reached during standing or during locomotion. This finding required the use of a novel analysis procedure in which the movement of the hand was compared relative to a fixed, world-centered frame of reference (normally used in prehension research), and to a body-centered frame of reference (i.e., the trunk).…”

The role of lower peripheral visual cues in the visuomotor coordination of locomotion and prehension

“…Although Georgopoulus and Grillner's paper is highly cited, only few subsequent studies have actually addressed the question of how walking and prehension are integrated and controlled. A common finding of these few studies is that reaching and grasping movements while walking are organized in hierarchical fashion, in a way that gait is adjusted based on the demands of the reaching and grasping task [2]. It has also been found that changes in gait imposed by the reaching task constraints may be task dependent [3,4].…”

Step scaling and behaviour selection in a constrained set of manual material handling transfers

“…lifting), although a small number of studies have investigated the coordination between stepping and grasping (Cockell, Carnahan, and McFadyen 1995;Marteniuk and Bertram 2001;van der Wel and Rosenbaum 2007).…”