The gradual incorporation of new sentence constructions and expressions, first encountered through AI interaction, into a user's own habitual syntactic repertoire over time.
Tracked as the changing frequency of AI-originated syntactic structures in the user's unaided writing across successive periods; the trend is the rise of those structures in independent production.
Proposed measurement protocol (not yet empirically validated): Longitudinal syntactic frequency: the rate of targeted AI-originated constructions per 1000 words in the user's unaided writing, sampled at intervals, with the within-person frequency trajectory as the outcome.