TY - JOUR IS - 39 ID - discovery85106 TI - The Role of Background Statistics in Face Adaptation Y1 - 2009/09/30/ A1 - Wu, JH A1 - Xu, H A1 - Dayan, P A1 - Qian, N PB - SOC NEUROSCIENCE JF - The Journal of Neuroscience SN - 0270-6474 KW - human visual-system KW - information-transmission KW - 2nd-order motion KW - image statistics KW - natural images KW - facial motion KW - cortex KW - 1st-order KW - psychophysics KW - recognition N1 - Copyright of all material published in The Journal of Neuroscience remains with the authors. The authors grant the Society for Neuroscience an exclusive license to publish their work for the first 6 months. After 6 months the work becomes available to the public to copy, distribute, or display under a Creative Commons Attribution 4.0 International (CC BY 4.0) license (https://creativecommons.org/licenses/by/4.0/). N2 - Cross-adaptation is widely used to probe whether different stimuli share common neural mechanisms. For example, that adaptation to second-order stimuli usually produces little aftereffect on first-order stimuli has been interpreted as reflecting their separate processing. However, such results appear to contradict the cue-invariant responses of many visual cells. We tested the novel hypothesis that the null aftereffect arises from the large difference in the backgrounds of first- and second-order stimuli. We created second-order faces with happy and sad facial expressions specified solely by local directions of moving random dots on a static-dot background, without any luminance-defined form cues. As expected, adaptation to such a second-order face did not produce a facial-expression aftereffect on the first-order faces. However, consistent with our hypothesis, simply adding static random dots to the first-order faces to render their backgrounds more similar to that of the adapting motion face led to a significant aftereffect. This background similarity effect also occurred between different types of first-order stimuli: real-face adaptation transferred to cartoon faces only when noise with correlation statistics of real faces or natural images was added to the cartoon faces. These findings suggest the following: (1) statistical similarities between the featureless backgrounds of the adapting and test stimuli can influence aftereffects, as in contingent adaptation; (2) weak or null cross-adaptation aftereffects should be interpreted with caution; and (3) luminance- and motion-direction-defined forms, and local features and global statistics, converge in the representation of faces. SP - 12035 AV - public UR - http://dx.doi.org/10.1523/JNEUROSCI.2346-09.2009 EP - 12044 VL - 29 ER -