Unveiling the digital confidant: How artificial intelligence psychotherapists surpass human counterparts in enhancing privacy disclosure intention

In an era in which millions seek mental health support, they paradoxically turn to nonsentient algorithms for their most intimate confessions. Why do some people feel safer in disclosing their deepest fears to a machine than to a fellow human? Challenging the traditional axiom that physical proximity fosters psychological intimacy, this research employs privacy calculus theory to investigate how psychotherapist type (offline human, online human, and artificial intelligence, hereafter AI) influences privacy disclosure intention. Across five vignette-based experiments with Chinese online participants (Ntotal = 1461), we demonstrate that participants report significantly higher disclosure intentions toward AI psychotherapists than toward both offline and online human psychotherapists. This effect is mediated by reduced fear of negative evaluation, which is particularly salient among individuals with low authenticity (both state and trait), and the effect also generalizes to a male psychotherapist. We identify a critical boundary condition: proactively disclosing a privacy security policy attenuates the higher disclosure intentions toward the AI psychotherapist, revealing a nuanced trade-off between mitigating social judgment risk and activating data privacy risk. Our findings suggest that AI can serve as a valuable supplemental tool to lower disclosure barriers for stigma-sensitive populations, but caution that standard transparency practices may paradoxically suppress candor in this unique context. We extend privacy calculus theory by identifying fear of negative evaluation as a central social-evaluative cost and by distinguishing social from technical dimensions of privacy risk. This research offers guidance for designing ethically responsible AI psychotherapeutic tools that lower disclosure barriers for stigma-sensitive users while maintaining transparency and accountability.