Masking of faces by facial and non-facial stimuli

A visual masking technique was used as a tool to study the recognition of well-known faces. Famous faces, but unknown masks were used. The visual relation between target and mask was varied; the effect was measured in terms of the thresholds for reports of “familiarity” and the ability to name the target. Three experiments are reported, all of which employed a backward-masking paradigm. The target and mask had equal display times, and there was no interstimulus interval. Significant masking was found with face masks but none from either object or noise masks. Intermediate levels of masking were found from faces that were inverted, jumbled, or had their inner features removed. The third experiment found that face masks that were similar to the targets had an effect equal to dissimilar ones. In all three experiments no interaction was found between the type of mask and the thresholds for the familiarity and naming criteria. The results are discussed in terms of information-processing models of face recognition, suggesting that masking occurs within the visual coding system but after categorization as a face. They also suggest that symbolic description as faces occurs rather later than has been sometimes assumed.