A Pilot Study of Non-invasive Brain Stimulation to Boost the Efficacy of Psychotherapy in a Community Sample of People Who Drink Alcohol

Transcranial Alternating Current Stimulation to Boost the Efficacy of Motivational Interviewing

The goal of this small (n=75) proof-of-concept randomized clinical trial is to test the effects of transcranial alternating current stimulation (tACS) during motivational interviewing (MI) sessions with participants who drink at above the low-risk level. Participants will be randomized to receive either MI with active stimulation, MI with sham stimulation, or a delayed treatment group that receives MI with no stimulation. Measures will include brain imaging, alcohol use, cannabis use, risk-taking behavior, emotions, and others. Participants who are randomized to the delayed-treatment group will not receive brain imaging.

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.

Inclusion criteria:

• Self-identify as having problem drinking
• Right-handed
• Age 21-60 years
• AUDIT score indicating risky drinking

Exclusion criteria:

• Left-handed or ambidextrous
• Currently engaged in treatment for alcohol use disorder
• Receiving treatment for alcohol use disorder within the prior 12 months
• History of brain injury or neurological diagnosis
• Evidence of current psychosis
• Past-year substance use disorder other than alcohol, marijuana, or nicotine
• Current or history of severe alcohol withdrawal
• MRI/tACS contraindications including pregnancy
• Impaired hearing (psychotherapy using American Sign Language is not possible within the scope of the proposed study)
• Insufficient corrected visual acuity to complete the assessment instruments
• Unable to read/speak English fluently
• Unable to provide valid informed consent