Citation

Van Gelder P, Lebedev S, Liu PM, Tsui WH. Vision Res. 1995; 35(5): 667-678.

Affiliation

Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962.

Copyright

(Copyright © 1995, Elsevier Publishing)

DOI

unavailable

PMID

7900305

Abstract

The dramatic improvement in smooth pursuit performance seen while analyzing the pursuit target has been ascribed to attention enhancement. With a periodic constant velocity target trajectory we ran a concurrent listening condition instead, to see if this mild distraction would degrade performance. Performance improved somewhat with the listening task, suggesting that displacing attentional effort from pursuit accuracy, rather than increasing it, brings better pursuit performance. Catch-up saccades were evenly distributed across tracking, listening, and target analysis conditions, but anticipatory and overshooting saccades were almost eliminated with target analysis. Thus the poor pursuit seems to have been caused by anticipatory and overshooting saccades, produced erroneously in the attempt to perform purposive smooth pursuit. Pursuit velocity immediately following anticipatory saccades was reduced such that the target would catch up with the point of gaze when it reached the endpoint of its trajectory, indicating a predictive goal other than instantaneous target foveation and velocity match.

Language: en