Title
Stimulus sequence effects on human express saccades described by a Markov model.
Abstract
Express saccades predominantly occur in experiments employing the gap paradigm where the target onset is separated from the fixation point offset by a blank period. Their relative frequency is distinctly influenced by catch trials (i.e. trials without a saccadic target) mixed into the stream of regular target trials. Generalizing this concept for other stimulus uncertainties (direction, amplitude), we found that the preparation time of a saccade depends on both the type of uncertainty used and the sequence of trial type (e.g., target vs catch, left vs right) in the experiment. This stimulus sequence effect is most prominent for catch trials. A similar but less pronounced effect can still be observed in the case of direction uncertainty but not in that of amplitude uncertainty. A two-state Markov process model is proposed which is based on the dichotomy of express and regular saccades in the gap paradigm. According to this model the actual state of the saccadic system, which determines the type of saccade just in preparation, depends on the “trial history”. The implications for models of saccade programming are discussed.
Year
DOI
Venue
1994
10.1007/BF00197605
Biological Cybernetics
Keywords
Field
DocType
Markov Model,Trial Type,Catch Trial,Target Onset,Target Trial
Markov process,Control theory,Artificial intelligence,Stimulus (physiology),Saccadic masking,Amplitude,Computer vision,Markov model,Speech recognition,Saccade,Perception,Mathematics,Offset (computer science)
Journal
Volume
Issue
ISSN
70
3
0340-1200
Citations 
PageRank 
References 
1
1.09
0
Authors
2
Name
Order
Citations
PageRank
Martin Jüttner122.11
Werner Wolf23910.18