We are grateful to Karin Wilken for her assistance in data collection.Environmental conditions bias our perception of other peoples’ facial emotions. This becomes quite relevant in
potentially threatening situations, when a fellow’s facial expression might indicate potential danger. The present
study tested the prediction that a threatening environment biases the recognition of facial emotions. To this end,
low- and medium-expressive happy and fearful faces (morphed to 10%, 20%, 30%, or 40% emotional) were
presented within a context of instructed threat-of-shock or safety. Self-reported data revealed that instructed
threat led to a biased recognition of fearful, but not happy facial expressions. Magnetoencephalographic correlates
revealed spatio-temporal clusters of neural network activity associated with emotion recognition and contextual
threat/safety in early to mid-latency time intervals in the left parietal cortex, bilateral prefrontal cortex, and the
left temporal pole regions. Early parietal activity revealed a double dissociation of face–context information as a
function of the expressive level of facial emotions: When facial expressions were difficult to recognize (lowexpressive), contextual threat enhanced fear processing and contextual safety enhanced processing of subtle
happy faces. However, for rather easily recognizable faces (medium-expressive) the left hemisphere (parietal
cortex, PFC, and temporal pole) showed enhanced activity to happy faces during contextual threat and fearful
faces during safety. Thus, contextual settings reduce the salience threshold and boost early face processing of lowexpressive congruent facial emotions, whereas face-context incongruity or mismatch effects drive neural activity
of easier recognizable facial emotions. These results elucidate how environmental settings help recognize facial
emotions, and the brain mechanisms underlying the recognition of subtle nuances of fear.German Research Foundation (DFG)
BU 3255/1-1
Ju2/024/15
SF58C0
