• Published 2013


In many selection experiments, comparisons have been made between a condition in which a row is cued, and various conditions in which attributes such as color, size or class serve as the selection criterion. In the latter conditions, the target items are scattered randomly throughout the display. Row report has always been the most successful, but since selection criterion and target-set configuration are confounded, it is inappropriate to conclude that row selection is more efficient that, say, color selection. Experiment I was designed to unconfound selection criterion and target-set arrangement, and to investigate some of the properties of different arrangements that might be responsible for performance differences. In a 5 x 5 matrix, five positions contained red letters, and S^was instructed to report only these letters. The color, in effect, served as a simultaneous cue directing attention to particular positions. Two characteristics of the target configuration, connectedness and codability, were varied. Two levels of each were combined factorially to yield four target pattern conditions: rows, arbitrarily chosen patches, spread-out symmetric designs, and random scatters. In addition, target-background similarity was varied since it is possible that any spatial effects in previous experiments are specific to the highly similar backgrounds used and not to target-set patter per ee. Four backgrounds (Black letters, black numbers, open black squares, or blank) were combined factorially with the four target-set patterns to yield 16 selection conditions. The main effect of Pattern was highly significant; performance was best in the row condition and much worse on all other patterns. Background was also very important; performance was best in the blank background condition and decreased systematically with increasing target-background similarity. There was also a strong interaction between Pattern and Background; when no background items were present, there was little effect of Pattern, and when targets were in a row, the nature of the Background was relatively unimportant. Clearly, much of the row-color difference found in previous experiments is due to spatial effects alone. Since performance was high and relatively invariant with Pattern in th«. blank background condition, it is suggested that target pattern per se is not crucial; rather the pattern serves to control the amount of interference from the background. The row pattern may be superior because of short-term memory coding advantages: The row pattern is easily described, and a row tag plus an ordered list of elements allows S to pair positions and elements accurately. The other three patterns are more difficult to

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@inproceedings{Bennett2013HUMANPC, title={HUMAN PERFORMANCE CENTER DEPARTMENT OF PSYCHOLOGY Spatial Effects in Visual Selective Attention}, author={I F Bennett and FURNISHED CONTAINED and Inge F.Bennett and «EPORT OATC}, year={2013} }