The effects of target discriminability and retinal eccentricity on saccade latencies: an analysis in terms of variable-criterion theory.
Two experiments are reported that studied changes in saccade latencies (SLs) in a target-identification task as a function of target discriminability and eccentricity. SLs were found to be longer when target discriminability was low and eccentricity was large, both factors showing a significant interaction. Variable-criterion theory (Grice, 1968) was used to derive a working model of the perceptual and decisional processes influencing SLs in the present task. Application of the measurement operations of the theory provided a good quantitative description of individual SL distributions. The analyses in terms of variable-criterion theory suggest that the perceptual process influencing SLs starts earlier and operates at a faster rate when the saccade target can be discriminated on the basis of global-visual features (e.g., size) than when local features (e.g., gaps) have to be extracted.
Nazir
T A
TA
Laboratorie de Psychologie Expérimentale, Centre National de la Recherche Scientifique (CNRS), Université René Descartes, Paris, France.
Jacobs
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AM
D000328:Adult; D001288:Attention; D004193:Discrimination Learning; D006801:Humans; D010364:Pattern Recognition, Visual; D011601:Psychophysics; D011930:Reaction Time; D012438:Saccades; D014794:Visual Fields