Who Writes the Self? Identity Shift Persists Under AI-Assisted Writing

Identity shift theory holds that selective online self-presentation can shift self-perception toward the portrayed identity, but its mechanisms assume that the presenter wrote the presentation. Generative AI now lets people publish self-presentations they did not fully compose. In a preregistered 2 (extraversion vs. introversion) × 3 (manual writing, AI outline, AI draft) experiment (N = 388), participants assigned to present extraversion rated themselves as more extraverted than those assigned to present introversion (d = 0.32), and the size of this identity shift did not differ across authorship conditions. AI involvement changed the writing process. Participants in both AI conditions searched their memories more deliberately for fitting examples, and participants who edited an AI draft felt less ownership of their text than those who wrote from an AI outline. Neither process accounted for the shift. The presenter need not be the sole author of a self-presentation for it to shape self-perception.