Organic Passing in AI-Mediated Persuasion: How Perceived Humanness Shapes Business Communication Outcomes

As AI-driven spokesperson technologies proliferate in professional communication, communicators need evidence about how audiences evaluate synthetic presenters. This experimental study ( N = 561) tested whether synthetic humanlike spokespersons (SHS avatars) can match human presenters in high-stakes persuasive contexts. Participants viewed identical business pitch videos delivered by either a human or an SHS avatar and then rated perceived message effectiveness (understandability, memorability, persuasiveness) and brand impression (competence, trustworthiness, likability). Results showed no significant main effects of actual modality. Instead, perceived humanness, coined and theoretically developed here as organic passing , was the decisive factor: viewers who believed they were watching a human rated both message effectiveness and brand impression significantly higher. SHS avatars achieved ~50% organic passing, and a cluster analysis revealed distinct audience segments that varied by detection ability and receptivity. These findings indicate that audience perception, not technical modality, drives outcomes in AI-mediated professional communication, offering a receiver-side mechanism useful for future researchers and practical design guidance for ethical, effective deployment of synthetic spokespersons.