The effects of face inversion on the perception of long-range and local spatial relations in eye and mouth configuration

A recent study hypothesized a configurational anisotropy in the face inversion effect, with vertical relations more difficult to process. However, another difference in the stimuli of that report was that the vertical but not horizontal shifts lacked local spatial references. Difficulty processing long-range spatial relations might also be predicted from a relevance-interaction explanation, which proposes that in inverted faces, spatial relations are processed efficiently only within high-relevance local regions. The authors performed 2 experiments to distinguish between these hypotheses. Experiment 1 showed that the inversion effect for vertical shifts of the eyes alone was more similar to that for horizontal eye shifts than for vertical shifts of the eyes and eyebrows. In Experiment 2, focused attention reduced the inversion effect for vertical mouth position more than that for vertical shifts of the eyes and brows. The authors concluded that face inversion impairs the perception of both local spatial relations in low-relevance regions and long-range spatial relations extending across multiple facial regions, consistent with a loss of efficient whole-face processing of the spatial relations between features.