Self-affirmation in auditory persuasion

Persuasive health information can be presented through an auditory channel. Curiously enough, the effect of voice cues in health persuasion has hardly been studied. Research concerning visual persuasive messages showed that self-affirmation results in a more open-minded reaction to threatening information (Harris & Napper, 2005). In the current studies, self-affirmation will be investigated in an auditory persuasion context. Moreover, the effect of voice cues, most notably voice pitch, will be explored. Respondents listened to a persuasive message spoken by a male or female voice, while no visual cues were available. The first study showed that after listening to a female voice, the intention to change the health behavior was high, regardless of self-affirmation. Hearing a male voice only led to a high intention after self-affirmation. Thus, a defensive response was likely to occur when no self-affirmation was provided. We showed that voice pitch is the most important voice cue to differentiate between a male and female voice. Finally, relations between voice pitch and source characteristics have been explored. The first study showed that voice pitch is positively related to credibility and honesty, especially within the female voice condition. In the second study, different relations with voice pitch emerge within both gender categories. Variations in voice are relevant in auditory health persuasion. Still, more research is needed to gain insights in the involved mechanisms