On ignoring irrelevant dimensions of common familiar stimuli

Abstract

Line drawings of four animals, each differing in size and orientation, were paired with each other in all possible combinations and presented in a successive matching task. In the first experiment, the subjects responded “same” if the stimuli had the same name. The “same” RT was faster for physically identical stimuli than for stimuli that differed on one or two dimensions but still had the same name. “same” responses were about twice as slow as “different” responses, a finding confirmed in the second experiment, in which subjects responded “same” only to physically identical stimuli. It was suggested that slower “same” responses may result from a general picture-processing strategy in which differences were noticed faster than similarities.