Augmenting Single-session Behavioral Activation (BA) With Delta-beta Transcranial Alternating Current Stimulation (tACS) for the Treatment of Depression

Augmenting Single-session Behavioral Activation (BA) With Delta-beta Transcranial Alternating Current Stimulation (tACS) for the Treatment of Depression

Investigating whether delta-beta cross-frequency transcranial alternating current stimulation can augment the effects of a single session of behavioral activation in participants with major depressive disorder.

The purpose of this study is to examine whether concurrent transcranial alternating current stimulation (tACS) augments the effects of a single session behavioral activation (BA) treatment of depression. Following a series of clinical assessments, participants will perform a reward-based decision-making task while electroencephalography (EEG) is collected.

Then, all participants will take part in a single-session 90-minute BA intervention; half of the participants will receive delta-beta tACS during the final 30 minutes of the session and half will receive an active sham stimulation. Participants will return two weeks later for another task-based EEG. Four weeks after the intervention session, they will receive self-report questionnaires via email to complete online.

Inclusion Criteria:

• 18 years old or order
• Able to provide informed consent
• Willing to comply with all study procedures and be available for the duration of the study
• Speak and understand English
• DSM-5 diagnosis of major depressive disorder (MDD) as assessed by the MINI

Exclusion Criteria:

• Participants must not have active suicide intent as determined by the Columbia Suicide Severity Rating Scale (C-SSRS). Active suicide intent will be captured in responses to items 4 and/or 5 on the C-SSRS.
• Participants must not meet criteria for current severe substance use disorder, anorexia nervosa, or active psychosis as captured by the MINI.
• Participants may not currently be in psychotherapy and have not received any other psychotherapy and/or stimulation (ECT, TMS) within the last 4 weeks.
• Any participants taking psychotropic medication must be on a stable dose for at least 4 weeks with no planned dose changes within the next 4 weeks.
• (for female participants) Participants must not be pregnant or breastfeeding.
• Participants may not have any medical or neurological illness for which symptom presentation or treatment could interfere with study participation
• Participants may not have undergone prior brain surgery
• Participants may not have any brain devices/implants, including cochlear implants and aneurysm clips
• Participants may not have had brain injury or concussion within the last three months
• Participants may not have a history of brain injury requiring current treatment