The neural correlates of face-like expertise in fingerprint examiners

Abstract

Upright faces produce a smaller, earlier N170 component than inverted faces but this relation reverses when noise is added. We suggest that the N170 latency delay with inversion and the amplitude reversal with noise are two signatures of different modes of processing for expert stimuli and that expertise might develop via configural mechanisms. As a test of this, we extend these findings into the domain of fingerprint examiners by presenting both upright and inverted faces and fingerprints in no-noise and noise-added conditions. We test both latent print examiners and novices. We establish the classic face inversion effect for faces presented in no-noise and replicate the amplitude reversal for faces in noise in both experts and novices. We establish the classic face inversion effect for fingerprints presented in no-noise and replicate the amplitude reversal for fingerprint in noise, but only for latent print examiners. Thus fingerprints appear to be processed similarly to faces in latent print examiners. The results suggest that face-like expertise can extend into other domains and the timing of these effects place constraints on the locus of the neural substrates. We propose a model in which expertise stimuli are processed via different modes and are less affected by the addition of external noise.