A Neuro-Influence Experiment to Evaluate the Persuasiveness of Pre-Exposure Prophylaxis Promotion Messages Among Men Who Have Sex With Men: Protocol for a Randomized Controlled Trial.

BACKGROUND: Pre-exposure prophylaxis (PrEP) is recommended by the US Centers for Disease Control and Prevention, but behavioral factors limit uptake, especially among men who have sex with men. A better understanding of how humans cognitively process information may inform health message development to promote PrEP uptake. OBJECTIVE: This paper is informed by the neuroscience of persuasion and influence and describes the protocol of a neuro-influence experiment using functional near-infrared spectroscopy (fNIRS) to evaluate the persuasiveness of PrEP promotion messages among men who have sex with men in Baltimore, Maryland. METHODS: We will conduct a randomized controlled trial using fNIRS to measure brain activation among 60 participants viewing PrEP promotion messages either developed through a crowdsourcing open contest implemented by the study team or developed with a traditional social marketing approach. We will evaluate the effectiveness of PrEP promotion messages by assessing brain activation in the regions associated with persuasion and changes in PrEP willingness, behavioral intention, initiation, and action between the 2 groups. RESULTS: This study is funded by the National Institutes of Health (National Institute of Mental Health: R34MH116725). Participant recruitment and data collection were completed in October 2023. The first results are expected to be submitted for publication in 2024. CONCLUSIONS: In addition to providing insight into the effectiveness of PrEP promotion messages, this study will examine the feasibility, acceptability, and utility of neuroimaging techniques to evaluate PrEP promotion messages for high-risk men who have sex with men. The findings can also demonstrate the utility of fNIRS as a tool for preproduct testing of health campaigns and enable the public health community to deliver more effective messages to improve health outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/52546.