Trustworthy faces

Two typical signals of trustworthy faces are prominent cheekbones and higher inner eyebrows, with the reverse being automatically judged untrustworthy.

The researchers used real and artificially generated faces with the requisite features as stimuli in their experiment.

Here are the real and computer-generated faces, with trustworthiness ranging from low to high:

People were shown the faces for only 33 milliseconds: that’s one-third the time it takes for even the fastest blink.

Then, just to make sure the face didn’t reach conscious awareness, they were immediately shown another face for one-third of a second — by comparison, half an ice-age.

This stops the brain consciously processing the first face.

Despite these efforts to make it hard to perceive the faces, brain imaging revealed that the amygdala — a structure important in social judgement of faces — showed activity that suggested it was tracking their relative trustworthiness.

Source: www.zmescience.com; www.spring.org.uk