Salivary α-amylase levels as a biomarker of experienced fear.

We recently reported data related to emotions collected in conjunction with a museum exhibit on emotion (Goose Bumps!-The Science of Fear).1 In this addendum, we present additional data collected as part of that study. We collected two commonly measured indices of emotional arousal, salivary cortisol and α-amylase, before and after participants had gone through a realistic fear challenge course as part of the exhibit. We found that α-amylase, but not cortisol, showed a highly specific increase only for those participants who endorsed both emotional arousal and negative valence. By contrast, the fear-inducing course resulted in high arousal but positive valence in some participants; in these, no increased α-amylase was measured. We conclude that salivary α-amylase is a promising biomarker for fearful experiences, and suggest that it is important to pay attention to positively valenced arousal that may be induced by fearful stimuli in a laboratory setting.