Our work on fear sweat intensity is out now in Phil Trans B and PsychScience. Here, we tested the prediction that the brain encoded human fear sweat in a dose-dependent fashion. Put more simply, we asked whether the intensity of fear experienced by a sender (individual producing sweat) can be decoded by a receiver (individual smelling the sweat).

Across behavior, physiology, and the brain, we saw main effects of fear vs neutral sweat (biased face processing, increased sniffing, fusiform activation). However, we predominantly saw dose-invariant responses across fear sweat intensities (no differences in fear intensity, except amygdala), suggesting the brain may engage an all-or-none mechanism for processing fear chemosignals.