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Understanding the central processing limit in consistent-mapping visual search tasks.

D L Fisher·S A Duffy·C Young·A Pollatsek
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Abstract

Effects of load (i.e., the number of stimuli in the display) have been observed in multiple-frame studies using a consistent mapping of stimuli to responses (e.g., Fisher, 1982, 1984). In a series of four experiments, it is shown that these effects are not the consequence of differences across the high- and low-load conditions in either decision noise or peripheral masking. Additionally, it is shown that of two modes of limited capacity (a limited-channel and divided-capacity model) considered as possible explanations of load effects in tasks where subjects are required to locate a target, only one--the limited-channel model--is consistent with the results from all three location tasks. Finally, it is argued that the limited-channel model predicts not only the behavior observed in the four consistent-mapping experiments reported in this article but also the behavior observed in several related consistent-mapping tasks (Kleiss & Lane, 1986; Shiffrin & Gardner, 1972).

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AttentionDiscrimination LearningForm PerceptionHumansPattern Recognition, VisualPerceptual MaskingVisual FieldsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D L Fisher, S A Duffy, C Young, A Pollatsek. 1988. Understanding the central processing limit in consistent-mapping visual search tasks.. https://doi.org/10.1037/%2F0096-1523.14.2.253

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