The dynamic process of ambiguous emotion perception.

Everyday social interactions hinge on our ability to resolve uncertainty in nonverbal cues. For example, although some facial expressions (e.g. happy, angry) convey a clear affective meaning, others (e.g. surprise) are ambiguous, in that their meaning is determined by the context. Here, we used mouse-tracking to examine the underlying process of resolving uncertainty. Previous work has suggested an initial negativity, in part via faster response times for negative than positive ratings of surprise. We examined valence categorizations of filtered images in order to compare faster (low spatial frequencies; LSF) versus more deliberate processing (high spatial frequencies; HSF). When participants categorised faces as "positive", they first exhibited a partial attraction toward the competing ("negative") response option, and this effect was exacerbated for HSF than LSF faces. Thus, the effect of response conflict due to an initial negativity bias was exaggerated for HSF faces, likely because these images allow for greater deliberation than the LSFs. These results are consistent with the notion that more positive categorizations are characterised by an initial attraction to a default, negative response.