Visual information for prospective control of tracking irregular target paths with isometric force production.

The prospective control of isometric force tracking was investigated as a function of the duration of visual information about past and future properties of target paths that varied in regularity. Longer duration of information specifying future behavior significantly enhanced performance when past information was not available. Furthermore, target path regularity differentially influenced local and global performance properties as the duration of prospective information increased. For more regular target paths, longer duration of prospective visual information improved local properties (e.g., decreased error), whereas, for less regular target paths, longer duration of prospective visual information enhanced global properties of force production (e.g., spectral slope). The strategies of prospective control depend on the interaction of the regularity of motor output and the available informational support.