Frames of Reference for Human Perceptual-Motor Coordination: Space-Based Versus Joint-Based Adaptation

Abstract

In this study, the authors addressed the issue of whether space-based motor planning occurs at a higher, equal, or lower level of central nervous system control than joint-based motor planning by using a computerized adaptation paradigm. Visual displays of participants' (N = 32) reaching movements to spatial targets were distorted either with respect to spatial hand displacements (space-based distortion) or with respect to joint angle displacements (joint-based distortion). Participants adapted more easily to space-based distortion than to joint-based distortion. The results suggest that when the participants were confronted with new visuomotor mappings, they aimed for virtual spatial targets whose positions were adjusted to compensate for the distortions associated with the new mappings. That strategy was preferred over a joint- or posture-based strategy, in which a posture is selected for the displayed spatial target and is then modified so that the new mapping between adopted and seen positions can be accommodated. The results support the widely held view that space-based planning occurs at a higher level than joint-based planning.

Posture-based motion planning: Applications to grasping.

“…Thus, our model is consistent with the claim that spatial targeting is more important than postural targeting. In fact, a recent adaptation study (Rogosky & Rosenbaum, 2000) explicitly tested the hypothesis that posture targeting is subordinated to spatial targeting. That study yielded positive conclusions about this hypothesis and its fit with the posture-based model.…”

Planning Reaching and Grasping Movements: Theoretical Premises and Practical Implications

“…In the following, we focus on simulation results. Behavioral tests of the model have appeared in other papers (Fischer et al, 1997 ;Rosenbaum et al ., in press ;Rogosky & Rosenbaum, 2000 ;Vaughan et al, 1998) . The simulation results that follow comprise a subset of those we have generated .…”

The Control Strategy for Degrees of Freedom in Remote Prehension with a Tool

“…The spatial path of the hand by this notion should curve and be subject to the movements of joints. The second view proposed that the movement control was extrinsic at hand space; joints might go through complex angular changes in order to ensure the spatial path of the hand in a straight line (Rogosky & Rosenbaum, 2000).…”