Movement velocity effects on kinaesthetic localisation of spatial positions.

In the present study, we examined how subjects locate spatial positions and code them in short-term memory. In the first experiment, blindfolded subjects were asked to perform movements in the near or far peripersonal space (criterion movement, CM). Then, subjects had to reach the end-point of CM (reproduction movement, RM). Movements could be performed either slowly or rapidly. Also, CM and RM could be performed with the same (congruent conditions) or different velocity (incongruent conditions). The results showed that performance was accurate in the two congruent conditions. Conversely, in the incongruent conditions, subjects made undershoot errors when the CM was fast and overshoot errors when it was slow. In the second experiment, blindfolded subjects also performed CM and RM in congruent or incongruent conditions. However, the CM and RM could start from the same or different position. We found again undershoot errors when the CM was fast and RM was slow and overshoot errors in the reverse condition. The results of both experiments suggest that the information about movement velocity contributes to the kinaesthetic coding in memory of a spatial location to be reached with arm movement.