Isolated Configuration: Holistic Processing Beyond the Realm of Faces

Holistic processing has traditionally been regarded as unique to faces, attributed to the spatial layout across facial features and their variability across individuals. However, whether such processing can occur in stimuli other than faces has remained an open and contentious question. Here, we show that novel non-face stimuli, which are designed to be differentiated strictly by configural properties, can drive holistic processing effects, while similar non-configural stimuli do not generate these effects. Using novel, abstract stimuli that isolate configural information, we systematically examined four effects typically associated with holistic face perception: the inversion, part-whole, composite, and misalignment effects. We observed all four effects with these stimuli, suggesting that this special form of visual processing extends beyond the realm of faces, and primarily requires that stimuli contain configural information for accurate classification. These effects manifested with minimal training, demonstrating that the visual system can rapidly integrate spatial relationships. Furthermore, convolutional neural networks, trained to categorize these stimuli, also show these effects, and like humans, these effects are only observed with the configural stimuli, and not with the non-configural stimuli. Our results challenge the traditional view of holistic processing as face-specific, and propose that configural processing itself serves as a primary driver of holistic perception and may be a fundamental visual process of its own.