Transcranial Direct Current Stimulation (tDCS) Therapy in Major Depression
About
Noninvasive transcranial direct current stimulation (tDCS) is a low-intensity neuromodulation technique of minimal risk that has been used as an experimental procedure for reducing depressive symptoms and symptoms of other brain disorders. Though tDCS applied to prefrontal brain areas is shown to reduce symptoms in some people with major depressive disorder (MDD), the extent of antidepressant response often differs. Methods that map current flow directly in the brain while a person is receiving tDCS and that determine how functional neuroimaging signal changes after a series of tDCS sessions may help us understand how tDCS works, how it can be optimized, and if it can be used as an effective antidepressant. Investigators will address these questions in a two-part randomized double blind exploratory clinical trial. For this part of the study, investigators will determine relationships between target engagement and clinical outcomes (mood) and functional sub-constructs of cognitive control and emotion negativity bias, and whether imaging markers at baseline predict changes in antidepressant response.
One hundred people with depression (50 in each group) will be randomized to receive either HD-tDCS or sham-tDCS for a total of 12 sessions each lasting 20 minutes occurring on consecutive weekdays. At the first and last session, subjects will receive 20-30 minutes of active or sham HD-tDCS in the MRI scanner, which will allow investigators to map tDCS currents, and track changes in regional cerebral blood flow (rCBF) pre-to- post treatment using completely non-invasive methods. At the first and last session and mid-way through the trial, participants will also complete a series of clinical ratings and neurocognitive tests.Eligibility
Inclusion Criteria:
- Capacity to provide informed consent;
- Meet DSM-5 criteria for a moderate-to-severe MDE, with Hamilton Rating Scale for Depression (HAMD) score of ≥14 and <24;
- Treatment naïve or on a stable standard antidepressant regimen (including selective serotonin reuptake inhibitors (SSRIs), serotonin-noradrenaline reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MOAIs) or tricyclic's (TCAs)) with no change in treatment 6-weeks prior to and during the tDCS intervention;
- Live within traveling distance to the University of California, Los Angeles (UCLA);
- Must refrain from making drastic hair-style changes throughout duration of study
Exclusion Criteria:
- Non-English speaking;
- Schizophrenia Axis I disorder;
- Primary anxiety disorder;
- Bipolar I disorder and psychotic disorders;
- Any neurological condition or major illness, including seizure disorder;
- Diagnosis of dementia of any type;
- Co-morbid substance abuse in the last three months;
- Contraindications to MR scanning (including pregnancy);
- Contraindications to tDCS (e.g., skin disease or treatment causing irritation);
- Treatment-resistant depression, with a history of a major depressive episode lasting > 2 years or failure to 2 or more antidepressant trials in the current episode;
- Any neuromodulation therapy (e.g., ECT, rTMS, DBS, VNS, or tDCS) within the last 3 months;
- Active suicidality;
- Current or past (within the last 1-month) use of anticonvulsants, lithium, psychostimulants, or dexamphetamine;
- Current use of decongestants or other medication previously shown to interfere with cortical excitability;
- Currently receiving any form of Cognitive Behavioral Therapy, Dialectical Behavioral Therapy, or Acceptance and Commitment Therapy