A, individual values for matching errors for a single subject. The subject's reference arm was placed at 85 deg, included angle, and the subject was asked to match its position with the other, indicator arm. Left-hand values, where the indicator had been extension conditioned (EC Ind). Right-hand values, where the indicator had been flexion conditioned (FC Ind). •, reference arm flexion conditioned (FC Ref); ○, reference arm extension conditioned (EC Ref). Errors were calculated as the difference in matching position between reference and indicator arms. Errors were scored as positive when position of the indicator arm was more extended than the reference arm and negative when the indicator arm was more flexed than the reference arm. Dotted line, zero error. B, mean position errors for each of eight subjects for the four conditions: FC Ref, EC Ref, EC Ind and FC Ind. Symbols as in A. To show the trends in the data, a solid line has been drawn between the FC Ref values and a dashed line joining EC Ref values. Dotted line, zero error. C, pooled means (± s.e.m) for the eight subjects. *Significant differences.