Effects of geometric distortions, Gaussian blur, and contrast negation on recognition of familiar faces

It is assumed that configural processing is important for recognizing people whom we know. Studies have shown better discrimination of relational changes between facial features when faces are presented upright than upside down and when presented as photographic negatives. However, studies have also demonstrated tolerance for complex changes to facial configuration of familiar faces when images are geometrically distorted. In two experiments, we explored effects of linear stretching, Gaussian blur, and contrast negation on recognition of familiar or unfamiliar faces (Experiment 1) and familiar or unfamiliar company brand logos (Experiment 2). Only contrast negation severely impaired recognition of familiar faces but not unfamiliar faces or company brand logos. Effects of contrast negation were additional to linear stretching, whereas linear stretching independently had no impact on recognition. These findings highlight an important deficit in the recognition of familiar faces caused by contrast negation.