Finding the fingerprints of generative AI in psychology publications

Generative artificial intelligence (AI) and in particular, large language models (LLMs) have become embedded in the research process, with scientists increasingly using LLMs to assist with manuscript drafting. Previous studies have documented the linguistic fingerprints of LLMs in biomedical and technical sciences, whereas psychology has remained largely unexplored. This study investigates the presence of AI-associated linguistic markers in psychology publications between 2020 and 2024. We constructed a corpus of 368,531 abstracts indexed in Scopus across 1,121 psychology journals and analysed the relative frequencies of 28 words previously identified as overrepresented in AI-assisted writing. Results indicated that the use of these stylistic markers remained stable from 2020 to 2022 but rose significantly following the release of ChatGPT, with relative frequencies increasing in 2023 and showing a substantial surge in 2024. Counterfactual modelling suggested that at least 9% of 2024 abstracts contained linguistic traces consistent with LLM editing. Group-level analyses revealed that increases were not confined to lower-prestige outlets as higher-ranked journals, major publishers, and both English- and non-English speaking countries all showed significant growth in AI-associated word use. These findings provide the first large-scale evidence that generative AI has measurably shaped the psychology publication record. The results raise critical implications for research integrity, transparency, and equity in scientific publishing. As psychology continues to address its credibility challenges, proactive standards, ethical guidelines, and detection practices will be essential for integrating AI tools responsibly into the scholarly ecosystem.