QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, December 10, 2003, 23(36):11305-11314

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (11) Citing Articles via Google Scholar Google Scholar Articles by Liston, D. Articles by Krauzlis, R. J. Search for Related Content PubMed PubMed Citation Articles by Liston, D. Articles by Krauzlis, R. J.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
Shared Response Preparation for Pursuit and Saccadic Eye Movements

Dorion Liston^1,2 and Richard J. Krauzlis¹

¹Systems Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, and ²Graduate Program in Neurosciences, University of California San Diego, San Diego, California 92093

Tracking a single target in the visual world requires coordination between pursuit and saccadic eye movements. The constraints imposed on pursuit and saccade decisions by visual processing and response preparation are difficult to compare because latency differences between the two movements provide different amounts of visual sampling time. The present study compares pursuit and saccade decisions when visual processing was directly manipulated. Human observers were asked to select between two stationary stimuli presented simultaneously at two different locations based on which had the higher contrast. The stimuli were presented for a brief, variable interval and then occluded by masks. Because the masks moved horizontally and were offset vertically, subjects were obliged to make both pursuit and saccadic eye movements to track the mask covering the target stimulus. For each of the exposure durations, we constructed oculometric curves for pursuit and saccades. We found that both systems had similar oculometric thresholds and response biases. The initial pursuit decisions differed from the subsequent saccade decisions on 1-13% of the trials but were the same more often than predicted by independent mechanisms. Moreover, pursuit reversed direction on discordant trials, so that the pursuit decision always matched that of the saccade by the time the saccade was started. These results support the view that, in addition to overlap in early visual areas and the final motor pathways, the pursuit and saccadic systems share processing at the level of response preparation. This shared processing may help ensure the coordination of pursuit and saccadic eye movements in selecting a single target.

Key words: pursuit; saccade; human; target selection; oculometric; attention; choice behavior; discrimination

---

Received July 15, 2003; revised October 1, 2003; accepted October 6, 2003.

This article has been cited by other articles:

				G. R. Case and V. P. Ferrera Coordination of Smooth Pursuit and Saccade Target Selection in Monkeys J Neurophysiol, October 1, 2007; 98(4): 2206 - 2214. [Abstract] [Full Text] [PDF]

				J.-J. Orban de Xivry and P. Lefevre Saccades and pursuit: two outcomes of a single sensorimotor process J. Physiol., October 1, 2007; 584(1): 11 - 23. [Abstract] [Full Text] [PDF]

				D. Schoppik and S. G. Lisberger Saccades exert spatial control of motion processing for smooth pursuit eye movements. J. Neurosci., July 19, 2006; 26(29): 7607 - 7618. [Abstract] [Full Text] [PDF]

				R. J. Krauzlis The Control of Voluntary Eye Movements: New Perspectives Neuroscientist, April 1, 2005; 11(2): 124 - 137. [Abstract] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help