A boolean or multi-valued map theory for symmetry detection
|has title::Interference from an irrelevant symmetric pattern in a color symmetry detection|
|Master:||project within::Cognitive Science|
|Student name:||student name::Valérie de Kemp|
|Second reader:||has second reader::Sander Los|
According to the Boolean map theory of visual attention it is only possible to see one feature value at a time, but it is possible to see more locations. For example, it is possible to see only one color at a time. In my study the Boolean map theory was tested. In Experiment 1 participants were shown matrices of squares in different colors. They had to indicate whether the pattern of one color, the target color, was symmetric. When the target pattern was symmetric, the reaction times and the error rates were lower, if there was a symmetric pattern in an irrelevant color. When the target was not symmetric it was the other way around. In Experiment 2 the objects in the matrices where not only squares, but also circles, triangles en crosses. When the target was symmetric participants were faster if there was an irrelevant symmetric pattern in color and shape and they were more correct if there was such a pattern or if there was an irrelevant symmetric color pattern. The results indicated that participants could not ignore the irrelevant symmetric pattern, when they attended the target pattern, suggesting that they could see two colors at a time. However the effect was greater when the irrelevant symmetric pattern was symmetric in color and shape, than when the pattern was only symmetric in color or only symmetric in shape. It was concluded that the Boolean map theory in the strict sense is untrue.