People's insight into their own behaviour and speech content while lying

The present experiment examined participants' insight into their own behavi our and speech content while lying. It was hypothesized that participants w ould believe that while lying they show more behaviour stereotypical of lyi ng than they in fact do (Hypothesis 1), whereas they would believe that the ir own speech content while lying contains fewer stereotypical features tha n in fact is true (Hypothesis 2). A stereotypical response was defined as a response people generally believe liars usually show. A total of 86 nursin g students were interviewed twice about a film they had just seen. During o ne interview they were asked to tell the truth whereas they had to lie in t he other interview. All interviews were videotaped, transcribed and then sc ored by independent coders. The coders' analyses reveal participants' actua l behaviour and speech content. participants themselves were asked to indic ate in a questionnaire how they believed they behaved and what they believe d they said in both interviews. To test the hypotheses, comparisons were ma de between participants' actual responses and their beliefs about their own responses. The results support both hypotheses and implications of these o utcomes for the detection of deception are discussed.