Distortions in the brain? ERP effects of caricaturing familiar and unfamiliar faces

Abstract

We report two experiments in which participants classified familiarity and rated best-likeness of photorealistic spatial caricatures and anti-caricatures (up to a distortion level of 30%) in comparison to veridical pictures of famous faces ( Experiment 1) and personally familiar faces ( Experiment 2). In both experiments there was no evidence for a caricature advantage in the behavioural data. In line with previous research, caricatures were perceived as worse likenesses than veridical pictures and moderate anti-caricatures. In Experiment 2, ERPs for familiar faces were largely unaffected by spatial caricaturing, whereas clear effects of caricaturing were observed for unfamiliar faces, for which caricaturing elicited increased occipito-temporal N170 and N250 responses. Whereas increases in N170 amplitude were limited to the first half of the experiment, increases in N250 were largest after a number of stimulus repetitions in the second half of the experiment. In the second half, ERPs to caricatured unfamiliar faces became more similar to ERPs to familiar faces, whereas ERP differences between familiar and unfamiliar faces remained prominent for veridicals and anti-caricatures. In the context of previous reports of caricature effects for line-drawings, these results imply that non-spatial (e.g., texture) information plays a prominent role for familiar face recognition, whereas spatial caricaturing may be particularly important for the recognition of unfamiliar faces, by increasing their distinctiveness.