Presenting information in a coherent fashion has been shown to increase processing fluency, which in turn influences affective responses. The pattern of responses have been explained by two apparently competing accounts: hedonic marking (response to fluency is positive) and fluency amplification (response to fluency can be positive or negative, depending on stimuli valence). This paper proposes that these accounts are not competing explanations, but separate mechanisms, serving different purposes. Therefore, their individual contributions to overall affective responses should be observable. In three experiments, participants were presented with businesses scenarios, with riskiness (valence) and coherence (fluency) manipulated, and affective responses recorded. Results suggested that increasing the fluency of stimuli increases positive affect. If the stimulus is negative, then increasing fluency simultaneously increases negative affect. These affective responses appeared to cancel each other out (Experiment 1) when measured using self-report bipolar scales. However, separate measurement of positive and negative affect, either using unipolar scales (Experiment 2) or using facial electromyography (Experiment 3), provided evidence for co-occurring positive and negative affective responses, and therefore the co-existence of hedonic marking and fluency amplification mechanisms.
Keywords: Processing fluency; affect; coherence; fEMG.