The Organization and Control of Sequential Movements

Werner F. Helsen1 & Digby Elliott2

1. Department of Kinesiology, Katholieke Universiteit Leuven, Belgium
2. Department of Kinesiology, McMaster University, Hamilton, Canada


When an individual performs two consecutive target-aiming movements, there is usually a temporal cost associated with the first movement compared to a situation in which the same movement is performed in isolation. However, this one target advantage does not occur if the accuracy demands imposed by the first target are low, and the second movement involves a reversal in direction. Recently, we have conducted a number of studies designed to distinguish between an on-line preparation and a movement integration explanation of these movement time effects. In one series of experiments, reaction time, movement time and dwell data indicate that the two components of both reversal and extension movements are prepared in advance of movement initiation. In the case of movement extensions, the one target advantage appears to result for processes related to the implementation of the second movement during the execution of the first movement. However, from the manipulation of vision during the execution of the first movement, it is clear that information about the relative position of the hand and the targets has an impact on the temporal characteristics of the entire movement sequence. These findings, and associated kinematic data, indicate that part of movement planning involves establishing procedures for the utilization of visual information during the execution of sequential movements.


This research was supported by the National Fund for Scientific Research in Belgium and the Natural Sciences and Engineering Research Council of Canada.