Effects of irrelevant information in speeded discrimination.

Selective attention to global and local levels in the comparison of hierarchical patterns

“…Using the dimensions of form and size or shading, Santee and Egeth found that subjects were able to selectively attend to form when the irrelevant dimension of size or shading varied in a speeded classification task, but they were not able to efficiently filter out irrelevant disparity in size or shading in a comparably designed "same"/"different" task. Other researchers have also found an interference from the irrelevant dimension when it was incompatible with the relevant one in a simultaneous-eomparisontask, both with dimensions that produced orthogonal interference in a speeded classification task (e.g., heights and widths of ellipses, and hues and tints of color patches, Dixon & Just, 1978), and with dimensions that produced no such interference in a speeded classificationtask (e.g., shape and size, Hawkins, McDonald, & Cox, 1973; and shape, size, and orientation of an interior line segment, Keuss, 1977). All of these fmdings suggest a possible difference between the processing demands of the two tasks.…”

Selective attention in the speeded classification and comparison of multidimensional stimuli

“…A comparison between these two paradigms based on the existing literature suggests that subjects cannot or do not filter out irrelevant information as efficiently in the simultaneous-comparison task as in the speededclassification task. That is, reaction time (RT) in the simultaneous-comparison task increases when the irrelevant dimension is in a state that is incompatible with the relevant dimension (Egeth, 1966;Hawkins, McDonald, & Cox, 1973;Hawkins & Shigley, 1972;Keuss, 1977). It is important to note that the dimensions that produced interference in these simultaneouscomparison studies (color, form, size of a circle, and tilt of an inscribed line) are dimensions that failed to produce orthogonal interference in a speededclassification task.…”

Processing of geometrical dimensions in a binary classification task: Evidence for a dual process model

“…Concerning the increase in RT same , it seems reasonable to suppose that it was at the response execution stage and, thus, after the operation of the fast identity reporter, that "state" incompatibility affected the response time (cf. Hawkins et al, 1973). Yet the RTdiff was more time consuming in spite of the "state" compatibility of relevant and irrelevant dimension, which requires an explanation that is directed towards stimulus processing instead of response interference.…”

“…It is clear that, in that case, the act of ignoring or neglecting irrelevant stimulus aspects may be helpful for the identity reporter. Or, to put it in analytical terms, the "same" responding system suffers from "state" incompatibility (Hawkins, McDonald, & Cox, 1973), since the irrelevant dimension calls for the opposite response to the relevant dimension. In contrast, when both relevant and irrelevant dimensions produce differences between the figures, the "different" responding system may in that case take advantage of "state" compatibility as both dimensions call for the "different" response.…”