An Informational Analysis of Active Kinesthesis as Measured by Amplitude of Movement

Abstract

5 blindfolded Ss were required to make absolute judgments of the extent to which their extended right arm was voluntarily moved in the horizontal plane. The first experiment entailed the judgment of 20 different amplitudes and from these data a scale of equal discriminability was constructed for each S. From these individual scales amplitudes were selected for 5 additional absolute judgment experiments where the number of amplitudes were varied from 4 to 16. Analysis of the mean equal discriminability scale showed that kinesthetic sensitivity varied over the continuum of movements. The primary analysis of information transfer between number of amplitudes of movement and responses indicated that information transfer varied considerably over the 5 experiments with a maximum transfer of 2.48 bits occurring when 16 amplitudes were used. These results were discussed in terms of the possible cues involved in movement discrimination and whether kinesthetic cues could be used in a closed-loop model of voluntary movement control.