When people scratch their nose, does it mean they are lying?
Popular psychology is full of accounts of ‘body language’. If I cross my arms, I’m being defensive; if I pull my ear, I’m likely to be lying; if I avoid your gaze, I’ve got something to hide.
The basis of body language is in animal communication. Without language, animals need ways to convey information to one another – and they use parts of their bodies in imaginative ways to do so. Faces are again important, but so too are, for example, gestures of submission. Mating relies heavily on signals of intent, receptivity or rejection, often leading to elaborate rituals.
The popularity of studying body language in humans owes much to Desmond Morris. He argued that information from animals could be extrapolated to humans. The scientific value of this area, social anthropology, has been questioned by many neuroscientists.
The neuroscience of body language has been studied much less well than responses to faces. But it does appear that the brain can recognise particular body postures and that recognition occurs early during processing of a scene (as is also true of face recognition). There could be brain modules specifically for body perception.
The body language responses studied to date seem to be closely linked to the brain’s emotional responses. So seeing someone showing signs of distress fires up our amygdala. This cues behaviour needed to escape from threatening stimuli (such as the need to run away very fast).
We also seem to be particularly sensitive to bodies in motion – though as artists through the century have proved, our emotional responses to still images of bodies in peril are powerful and quick to appear.Lead image:
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