The relationship between blushing propensity, social anxiety and facial blood flow during embarrassment.

To investigate blushing in relation to blushing propensity scores and core elements of social anxiety, facial blood flow was monitored in 86 normal volunteers during an embarrassing task (singing a children's song). Increases in facial blood flow were greater in women than men, as were scores on the Blushing Propensity and Fear of Negative Evaluation scales. In addition, high scores on the Blushing Propensity and Social Interaction Anxiety scales were associated with large increases in facial blood flow during singing. However, this appeared to be due primarily to social anxiety because the association between blushing propensity scores and changes in facial blood flow disappeared when social interaction anxiety scores were taken into account. These findings suggest that people generally base their beliefs about blushing on cues other than changes in facial blood flow. Social anxiety may augment increases in facial blood flow during embarrassment, independently of expected or perceived blushing.