Investigating the Causal Role of Prefrontal Control in Decision-making in Patients With Anhedonia (DEBRA)
Major Depressive Disorder, Anhedonia
About this trial
This is an interventional basic science trial for Major Depressive Disorder focused on measuring transcranial Alternating Current Stimulation, Goal-directed behavior, Cross-frequency coupling, Reward-based decision-making
Eligibility Criteria
Inclusion Criteria:
- Able to provide informed consent
- Have normal to corrected vision
- Willing to comply with all study procedures and be available for the duration of the study
- Speak and understand English
- Low suicide risk as determined by the Columbia Suicide Severity Rating Scale (C-SSRS), and by the Hamilton Depression Rating Scale (HAM-D; less than 3 for the suicidality item).
- Negative pregnancy test for female participants
- Patient Health Questionnaire (PHQ) with 9 items greater than or equal to 10 and a diagnosis of major depressive disorder on the Mini International Neuropsychiatric Interview (MINI)
Exclusion Criteria:
- Attention deficit (hyperactivity) disorder (currently under treatment)
- Neurological disorders and conditions, including, but not limited to: History of epilepsy, seizures (except childhood febrile seizures), dementia, history of stroke, Parkinson's disease, multiple sclerosis, cerebral aneurysm, brain tumors
- Medical or neurological illness or treatment for a medical disorder that could interfere with study participation (e.g., unstable cardiac disease, HIV/AIDS, malignancy, liver or renal impairment)
- Prior brain surgery
- Any brain devices/implants, including cochlear implants and aneurysm clips
- History of current traumatic brain injury
- (For females) Pregnant or breast feeding
- Anything that, in the opinion of the investigator, would place the participant at increased risk or preclude the participant's full compliance with or completion of the study
- Diagnostic and Statistical Manual of Mental Disorders version 5 diagnosis of present moderate or severe substance use disorder or alcohol use disorder, and past severe substance use disorder or alcohol use disorder, or psychotic disorder within the last 12 months
- Not taking medications for attention deficit (hyperactivity) disorder or benzodiazepines as these medications often produce specific EEG activity that may disrupt our interpretation of the findings
- If major depressive disorder is experienced in episode, the participant must currently be within a depressive episode.
- Contraindications for magnetic resonance imaging (MRI): ferrous metal inside the body, jewelry must be removable, pacemaker or cochlear implant.
Sites / Locations
- University of North Carolina at Chapel Hill
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Active Comparator
Sham Comparator
Delta-beta tACS
Theta-gamma tACS
Active-sham tACS
The study is investigating the use of transcranial alternating current stimulation (tACS). The stimulation is delivered at 1 milliampere (mA) zero-to-peak amplitude at the target electrodes and 2 mA zero to-peak amplitude at the return electrode. For the experimental arm, the tACS will be delivered using the cross-frequency stimulation waveform delta-beta (3-20Hz).
This arm serves as an active control where tACS will be delivered using the cross-frequency stimulation waveform theta-gamma (5-50Hz).
For active sham stimulation, either delta-beta or theta-gamma stimulation is delivered for 10 seconds and then returns to baseline. This is intended to mimic the skin sensations (e.g., itching, burning, tingling) that are experienced at the onset of stimulation, assisting with blinding the participant's assignment.