Contrast normalisation masks natural expression-related differences and artificially enhances the perceived salience of fear expressions.

ABSTRACT: Fearful facial expressions tend to be more salient than other expressions. This threat bias is to some extent driven by simple low-level image properties, rather than the high-level emotion interpretation of stimuli. It might be expected therefore that different expressions will, on average, have different physical contrasts. However, studies tend to normalise stimuli for RMS contrast, potentially removing a naturally-occurring difference in salience. We assessed whether images of faces differ in both physical and apparent contrast across expressions. We measured physical RMS contrast and the Fourier amplitude spectra of 5 emotional expressions prior to contrast normalisation. We also measured expression-related differences in perceived contrast. Fear expressions have a steeper Fourier amp

SUBMITTER: Webb ALM 

PROVIDER: S-EPMC7289429 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature