Effects of Movement Context on the Encoding of Kinesthetic Spatial Information

Abstract

Effects of movement context upon the encoding of kinesthetic spatial location information were examined in a series of experiments using a motor learning paradigm. A cross-modal, kinesthetic to kinesthetic plus visual feedback procedure was used in each experiment to determine the encoding characteristics of spatial information within a variety of movement conditions. Following knowledge of results trials, subjects performing in cross-modal conditions had significant directional errors (overshooting of the target) for spatial locations associated with specific and non-specific body-referents (Experiment 1), for different movement directions to the same target (Experiment 2), and for long (40 cm) movements (Experiments 2, 3) and short (15 cm) movements (Experiment 4). However, subjects in both intermodal and intramodal conditions who switched movement direction had significant undershooting of the spatial targets (Experiment 3). Movement context in terms of response endpoint location or movement length did not have an apparent effect on directional errors. Performances in all experimental conditions were biased in the direction of the movement during learning. The context provided by movement direction did influence the encoding of kinesthetic spatial information.