Fig. 2.

Behavioral encoding response data. Across images within each valence condition, significant correlations were found between (A) the picture-specific (group level) mean subjective brightness rating (from the EPO condition) and the objective picture luminance and (B) the picture-specific (group level) mean rating from the ISO condition and the picture’s normative arousal score (from IAPS and in-house, standardized database). (C) Average ISO ratings were entered into one-way ANOVAs with emotion (negative, neutral, positive) as a factor; ISO ratings also displayed a main effect of emotion (P < 0.0005), with emotional pictures (negative and positive) rated as more personally arousing than neutral pictures. Error bars denote standard error.