Language discloses the art of deception

7 October 2009

Faculty of Health Sciences' Phd student Gina Villar and Dr Joanne Arciuli are investigating linguistic cues to deception. Some of their findings, recently reported in the Herald Sun, indicate that language behaviours such as the use of 'um' can help distinguish truth from lies.

After conducting a study of US killer, Scott Peterson, the researchers found that he used the word "um" and verbs more often when he was telling the truth. Modifiers (adjectives and adverbs) appeared more frequently in his speech when he was lying. Peterson deceived the public and the media after killing his pregnant wife in 2002, by playing the role of the innocent grieving widow until his conviction three years later. Ms Villar conducted her study last year through Charles Sturt University, with Dr Joanne Arciuli from the University of Sydney and Dr David Mallard from Charles Sturt. This work has been presented recently at the Australian Psychological Society conference in Darwin.

"These findings are particularly interesting because they support findings from our laboratory-based study of low stakes lies showing that 'um' may appear more often in truthful than deceptive speech", said Ms Villar. "People often associate an increased use of 'um' with deceit. Perhaps the reduced use of 'um' during lying is a deliberate attempt on the speaker's part to appear more credible." This laboratory-based study has been accepted for publication in the journal of Applied Psycholinguistics and was presented by Dr Arciuli this year at the Cognitive Science conference in Amsterdam. "Because individuals may differ considerably in their natural language behaviour, the challenge for researchers is in establishing what constitutes an individual's usual, authentic pattern of communication and measuring any deviations from this when they are lying."

Ms Villar is now doing her PhD, under the supervision of Dr Joanne Arciuli and Dr Helen Paterson, on the influence of variables such as mental health on linguistic cues to deception, at the University of Sydney.