A study in affect: Predicting valence from fMRI data.

Previous studies have shown that affective valence states induced by brief stimulus presentations are identifiable from whole brain activation patterns observed with functional magnetic resonance imaging (fMRI). However, it is unclear whether those results will generalize to identification of continuous changes in affective valence states under naturalistic settings, such as watching a movie. We examined neural representations of signed (positive versus negative) and unsigned (valenced versus non-valenced) valence on previously collected fMRI data from 17 participants who watched a TV show episode in a passive viewing task in the scanner (Chen et al., 2017). These data were correlated with behavioral valence ratings from a separate group of 125 participants. We spatially localized both signed and unsigned valence representations and were able to predict valence ratings for most participants based on the signed valence model in a cross-participant cross-validation procedure. These findings extend previous results from controlled experimental studies to naturalistic settings, demonstrating the ecological validity of prior findings.