Thesis Defence: Lies, Smiles, and Self-Disclosure: An Examination of How Social Functional Smiles Mediate the Relationship Between Lying and Self-Disclosure

Cameo Brown, supervised by Dr. Leanne ten Brinke, will defend their thesis titled “Lies, Smiles, and Self-Disclosure: An Examination of How Social Functional Smiles Mediate the Relationship Between Lying and Self-Disclosure” in partial fulfillment of the requirements for the degree of Master of Arts in Psychology – Psychological Science.

An abstract for Cameo Brown’s thesis is included below.

Defences are open to all members of the campus community as well as the general public. Registration is not required for in-person defences.

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ABSTRACT

Lies are ubiquitous in interpersonal communication. Despite their prevalence, people are generally unsuspecting of deception in social interactions. Even when asked to evaluate veracity directly, people only perform slightly better than chance. Taken together, these findings suggest that lies are often ‘missed’ and people are easily duped. This study considers an alternative possibility; that people naturally restrict their interactions with liars (vs. truth-tellers), even in the absence of suspicion about deception. Specifically, I investigated whether people are less willing to disclose personal information to liars, relative to truth-tellers. Receivers (N = 230) watched videos of 20 senders claiming to like a target person. Half of these claims were true; the other half, deceptive. Following each video, receivers rated their willingness to share personal information in a hypothetical conversation with each sender. Consistent with my hypothesis, results demonstrated that individuals were less willing to self-disclose personal information to liars, relative to truth-tellers. Additionally, a novel set of behaviours—social functional smiles—were explored as potential mediators of this effect. Although I did not find support for these behaviours as mediators, the presence and duration of social functional smiles did vary by veracity. Truth-tellers engaged in more reward smiles and fewer dominance smiles, relative to deceptive senders. Taken together, this study enhances our understanding of senders’ behavioural cues to deception and receivers’ indirect reactions to lies in conversation.