Study of Delta-beta Brain Stimulation to Improve Goal-Directed Behavior in Adults with Anhedonic Major Depressive Disorder

What this Trial Is About

Researchers are studying major depressive disorder with a focus on anhedonia, which is the inability to seek out or feel pleasure and is linked to treatment resistance and reduced goal-directed behavior. This study evaluates how five consecutive days of brain stimulation affect neural activity and behavior in people experiencing a unipolar major depressive episode with significant anhedonia. The goal is to understand changes in brain connectivity related to goal-directed actions. Participants undergo eight sessions in total. The first session includes clinical assessments to confirm eligibility. The second session involves an MRI scan while completing reward-based tasks. Then, participants are randomly assigned to receive one of three types of non-invasive brain stimulation over five days delta-beta frequency stimulation, theta-gamma frequency stimulation, or a sham placebo stimulation designed to mimic sensations without active treatment. During stimulation sessions, participants complete goal-setting and action planning activities. Throughout the study, participants complete self-report assessments and EEG recordings during reward-based tasks to track changes in brain activity and symptoms. Sessions vary in length from about one to three hours. A follow-up visit occurs approximately two weeks after stimulation ends to evaluate lasting effects. The primary outcome is change in brain coupling strength one week after stimulation, with symptom changes assessed at four weeks. Safety and adherence are monitored throughout the study period.

Causal Role of Delta-beta Coupling for Goal-directed Behavior in Anhedonic Depression