Research

Publications, working papers, and ongoing projects

41

Publications

2,273

Citations

20

h-index

Selected Publications

Cover Story 2026 AAAS Newcomb Cleveland Prize

Durably reducing conspiracy beliefs through dialogues with AI

Costello, T.H., Pennycook, G., & Rand, D.

Science, 385, eadq1814 (2024)

In conversations with over 2,000 conspiracy believers, AI-driven dialogues reduced belief by ~20% on average—effects that persisted for at least two months. One in four participants completely reversed their stance.

DOI Press Coverage

Working Papers

2025

Reducing belief in conspiracy theories as they unfold using large language models

Costello, T.H.*, Rabb, N.*, Stagnaro, M. N., Pennycook, G., & Rand, D.

Working paper (* = shared first author)

2025

Deep canvassing using AI

Costello, T.H., Pennycook, G., Willer, R., & Rand, D.

Working paper

2025

Personalized dialogues with AI effectively address parents' concerns about HPV vaccination

Xu, H.G.*, Costello, T.H.*, Schwartz, J.L., Niccolai, L.M., Pennycook, G., & Rand, D.

Working paper (* = shared first author)

2025

Addressing climate change skepticism and inaction using human-AI dialogues

Czarnek, G., Orchinik, R., Lin, H., Xu, H.G., Costello, T.H., Pennycook, G., & Rand, D.G.

Working paper

2025

Just the facts: How dialogues with AI reduce conspiracy beliefs

Costello, T.H., Pennycook, G., & Rand, D.

Working paper

All Publications

For a complete list with links, please see my CV or Google Scholar.

41. Lin et al. (2025). Persuading voters using human–AI dialogues. Nature.

40. Boissin et al. (2025). Dialogues with LLMs reduce conspiracy beliefs even when perceived as human. PNAS Nexus.

39. Malka et al. (2025). Polarized attitudes and anti-democratic orientation. Political Studies.

38. Lowman, Costello, & Patrick (2025). Creating scale measures of latent factors. Assessment.

37. Bowes et al. (2025). Adversarial collaboration on rigidity. Political Psychology.

36. Costello (2025). LLMs as disrupters of misinformation. Nature Medicine.

35. Binnendyk et al. (2025). Is overconfidence a trait? Psychological Science.

34. Costello, Pennycook, & Rand (2025). Response to critics. Science.

33. Costello, Pennycook, & Rand (2024). Durably reducing conspiracy beliefs. Science.

32. Lilly et al. (2024). Identifying "types" of authoritarians. European Journal of Personality.

... and 31 more. See CV for complete list.

Interested in collaborating?

I'm always open to new collaborations, especially on projects at the intersection of AI and behavioral science.

Get in touch