A Pilot Study of the Immediate Effects of DLPFC tDCS on Attention Bias in Depression

A Pilot Study of the Immediate Effects of DLPFC tDCS on Attention Bias in Depression

Depression and other psychiatric conditions are marked by exaggerated, preferential processing (or attention bias) of negative information relative to neutral or positive information. This depression-related attention bias can be measured using the Dot Probe task and Visual Search, that allow assessment of the degree to which one shows bias toward negative information in the presence of neutral or positive information. A clinically effective treatment for depression is noninvasive brain stimulation with transcranial direct current stimulation (tDCS), targeting the dorsolateral prefrontal cortex (DLPFC), delivered in repeated sessions across a period of time. The study will test the effect of a single session of DLPFC tDCS on attention bias in patients with mild to moderate depression.

This prospective pilot study will recruit 25 female participants, ages 18-45 (inclusive), with mild to moderate depression (based on BDI-II score range 14-19 for mild and 20-28 for moderate) to determine if a single-session of tDCS can alter negative attention bias. The primary objective is to study if single-session tDCS will affect attention bias in depression and is not meant to treat depression. Subjects may or may not be receiving treatment for mild-moderate depression.

Inclusion Criteria:

• Aged 18-45
• Female
• Mild to moderate depression (determined by BDI-II scores of 14-19 and 20-28, respectively)
• If taking antidepressants, medication must be stable ≥ 30 days prior to screening

Exclusion Criteria:

• Wide-Range Achievement Test-Fourth Edition (WRAT-4) Reading Subtest standard score <85 (to ensure understanding of test procedures)
• Insufficient visual and motor ability to operate the intervention and assessments as judged by treating neurologist or study staff
• Primary psychiatric disorder other than depression (based on MINI)
• Primary neurologic condition that would prevent ability to participate (as determined by study clinician).
• History of head trauma in the last year
• Medical device implants in the head or neck
• History or current uncontrolled seizure disorder
• Current substance abuse disorder
• . Pregnant or lactating women
• Skin disorder/sensitive skin near stimulation locations