The effects of stimulus structure and familiarity on same-different comparison

It was hypothesized that performance in the same-different comparison task is based on two modes of processing: (1) structural processes that organize the detailed parts of a stimulus into a well-formed whole, and (2)analytic processes that decompose the stimulus into features. This hypothesis was supported, but with the unexpected finding of individual differences in the mode of processing underlying “same” responses. Those Ss in the “same” condition whose reaction times were faster for symmetrical than for asymmetrical patterns supported the hypothesis for structural processes. The remaining Ss in the “same” condition, as well as all the Ss in the “different” condition, were unaffected by symmetry. These Ss supported the hypothesis for analytic processes. Although familiarity effects were obtained for both structural and analytic Ss, the rotation of the familiar patterns into an unfamiliar orientation virtually eliminated familiarity effects for the structural Ss, but left them intact for analytic Ss.