Simple facial features will lead us to trust some faces above others.
Studies have shown that faces with higher inner eyebrows, pronounced cheekbones and a wide chin are judged as more trustworthy. The amygalda, a structure associated with a fear and other strong emotions, can respond to a face within 33 milliseconds – this is fast at 1/300 th of a second.
The people in the study were shown both real and computer generated faces for such short periods that they didn’t conciously see them. Despite the sublimal exposure of the face images, the people being studied were still able to make a judgements of trustworthiness.
The incredibly high speed evaluation makes sense in evolutionary terms since judging threats or detecting strangers as dangerous may have been crucial to survival. This means we shouldn’t be surprised when we get a felling about someone before we have actually recognised them.
We should be cautious with this information though, as despite showing a prference for trusting people with higher cheekbones and eyebrows, there is no study we are aware of to see if they are actually any more trust worthy than others.