A fascinating study has shown that we're unable to read insights into ourselves from watching a video of our own body language. It's as if we have an egocentric blind spot. Outside observers, by contrast, can watch the same video and make revealing insights into our personality. [...]
What was going on? Why can't we use a video of ourselves to improve the accuracy of our self-perception? One answer could lie in cognitive dissonance - the need for us to hold consistent beliefs about ourselves. People may well be extremely reluctant to revise their self-perceptions, even in the face of powerful objective evidence. A detail in the final experiment supports this idea. Participants seemed able to use the videos to inform their ratings of their "state" anxiety (their anxiety "in the moment") even while leaving their scores for their "trait" anxiety unchanged.
The British Psychological Society Research Digest Blog | We're unable to read our own body language