Fig. 7.

A: scatterplot of an exemplar participant's mean activity from the long-latency epoch between the PEC and BI. Open circles reflect individual trials in which the BI was preloaded and the mechanical perturbation extended the elbow and moved the hand away from the displayed target. r Value represents computed Spearman rank correlation coefficient. B: same format as A but for the BI and WF. C: black dots represent Spearman rank correlation coefficients computed for each participant from trial-by-trial mean muscle activity within the long-latency epoch between the PEC and BI, the BI and WF, the DELT and TRI, and the TRI and WE. Correlations involving the BI were derived from trials in which the BI was preloaded and the mechanical perturbation extended the elbow and moved the hand away from the target. Correlations involving the TRI were derived from trials in which the TRI was preloaded and the mechanical perturbation flexed the elbow and moved the hand away from the target. Red dots reflect the exemplar participant's correlation coefficient from A and B. Upward triangles reflect correlations computed from trials in which the elbow muscle was preloaded and the mechanical perturbation moved the hand into the target. Downward triangles reflect correlations computed from trials in which the elbow muscle was preunloaded and the mechanical perturbation moved the hand away from the target. AU, arbitrary units.