COARSE BLOBS OR FINE EDGES - EVIDENCE THAT INFORMATION DIAGNOSTICITY CHANGES THE PERCEPTION OF COMPLEX VISUAL-STIMULI

Efficient categorizations of complex visual stimuli require effective encodings of their distinctive properties. However, the question remai ns of how processes of object and scene categorization use the informa tion associated with different perceptual spatial scales. The psychoph ysics of scale perception suggests that recognition uses coarse blobs before fine scale edges, because the former is perceptually available before the latter. Although possible, this perceptually determined sce nario neglects the nature of the task the recognition system must solv e. If different spatial scales transmit different information about th e input, an identical scene might be flexibly encoded and perceived at the scale that optimizes information for the considered task-i.e., th e diagnostic scale. This paper tests the hypothesis that scale diagnos ticity can determine scale selection for recognition. Experiment 1 tes ted whether coarse and fine spatial scales were both available at the onset of scene categorization. The second experiment tested that the s election of one scale could change depending on the diagnostic informa tion present at this scale. The third and fourth experiments investiga ted whether scale-specific cues were independently processed, or wheth er they perceptually cooperated in the recognition of the input scene. Results suggest that a mandatory low-level registration of multiple s patial scales promotes flexible scene encodings, perceptions, and cate gorizations. (C) 1997 Academic Press.