The motivational impairment effect in the communication of deception: Replications and extensions

Past research (e.g., DePaulo & Kirkendol, in press) has documented a motivational impairment effect in the communication of deception, whereby people who are more highly motivated to get away with their lies (relative to those who are less highly motivated) are less successful at doing so whenever observers can see or hear any of their nonverbal cues. In the present study, we report a conceptual replication of the effect: Subjects who told ingratiating lies under conditions in which they thought that the ability to convey particular impressions was an important skill (high competence-relevance) were less successful at getting away with those lies when judges could observe their nonverbal behaviors. We also report a conceptual replication of an unpredicted finding from an earlier study (DePaulo, Stone, & Lassiter, 1985b): Under the same conditions (ingratiating lies, high competence relevance), women were more likely to show the motivational impairment effect than were men. We predicted in this study that more attractive speakers would be less susceptible to the motivational impairment effect than less attractive speakers. Consistent with this prediction, under high motivational conditions (ingratiating lies, high competence-relevance), more attractive speakers were less likely to show the impairment than were less attractive speakers. Finally, we report suggestive evidence that the motivational impairment effect may occur when subjects are trying deliberately to control simultaneously all of their verbal and nonverbal behaviors.This research was supported by an NIMH research grant and an NIMH Research Scientist Award to the first author. We thank Paul Ekman for his comments, and Ann Ashworth, Joan Hairfield, Bruce Hedrick, Morgan Kulow, Margaret Lluy, Terri Michell, Helen Ponte, Carissa Smith, and Debby Winokur for their help with this research.