New Scientist reacquaints us with the smell of fear:
Lilianne Mujica-Parodi, a cognitive neuroscientist at Stony Brook University in New York and colleagues collected sweat from the armpits of first-time tandem skydivers as they hurtled towards the earth.
The smell of their sweat was wafted under the noses of volunteers as they lay in an fMRI scanner. Even though they had no idea what they were inhaling, two separate sets of volunteers showed activation of the amygdala – the area of the brain responsible for emotion-processing, plus areas involved in vision, motor control and goal-directed behaviour. Sweat produced under non-stressed conditions didn’t produce this reaction.
What’s more, in behavioural tests, the “stress sweat” seemed to heighten people’s awareness of threat, making them 43 per cent more accurate in judging whether a face was neutral or threatening.