Transcranial Alternating Current Stimulation to Boost the Efficacy of Motivational Interviewing

This proof-of-concept randomized clinical trial will recruit n=75 people with problematic levels of drinking who are considering treatment for their alcohol use. These participants will be randomized to one of three conditions: a condition that applies active tACS during an MI session (MI+tACS), a condition that applies sham stimulation during an MI session (MI+sham), or a waitlist control condition (MI-only). Only participants the MI+tACS and MI+sham conditions will be included in the brain imaging portion of the study. One month after their intervention session, all participants will report their use of alcohol in the prior 30 days via an online assessment battery. This will allow us to test the effects of tACS on within-session client speech and outcomes.

Participants will have magnetoencephalography (MEG) scans including rest and an alcohol cue task to measure the acute effects of brain stimulation. Participants will also have MRI scans including structure and rest. The Motivational Interviewing Skill Code (MISC 2.5) and the CASAA Application for Coding Treatment Interactions (CACTI) will be used to assess counselor and participant speech in the recorded MI sessions and to ensure that sessions comply with the principles of MI.