Every look matters: appraisals of faces follow distinct rules of information integration under arousing versus non-arousing conditions.

In this research, we investigated whether appraisals of faces follow distinct rules of information integration under arousing versus non-arousing conditions. Support for this prediction was found in four experiments in which participants observed angry (and fearful) faces that were presented with a direct versus an averted gaze (Experiments 1a, b), on a red versus a grey background (Experiment 2), and after performing a motor exercise versus no exercise (Experiment 3). Under arousing conditions, participants' appraisals of faces reflected summation (i.e. extremely negative encounters were strengthened by moderately negative encounters) whereas, under non-arousing conditions, appraisals did not reflect summation (i.e. extremely negative encounters were weakened by moderately negative encounters) and could instead be accounted for by three alternative rules of information integration based on averaging, mere exposure, or the number of strong stimuli.