Cognitive Enhancement in Depression (The COG-D Study)

Purpose

This study will investigate whether transcranial direct current stimulation (tDCS) enhances the effects of computerized cognitive training in older adults with recurrent depression (2 or more lifetime episodes; either current or within past 3 years).

Conditions

  • Aging
  • Depression
  • Cognitive Symptom

Eligibility

Eligible Ages
Over 60 Years
Eligible Genders
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  • Age 60+ years - Diagnosis of a current or past (within last 3 years) depressive episode (e.g., Major Depressive Disorder (MDD), Persistent Depressive Disorder (PDD)) using Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria - In total, participants must have 2 or more lifetime depressive episodes to be considered "recurrent" - Either stable antidepressant regimen for at least 6 weeks or no current antidepressant treatment - Evidence of subjective cognitive complaints on the Everyday Cognition Scale (ECog) - English fluency

Exclusion Criteria

  • Other Axis I psychiatric conditions via the DSM-5, except for anxiety symptoms occurring in a depressive episode - Acute suicidality on clinical evaluation - Acute grief - History of alcohol use disorder or substance use disorder in last 12 months - Currently taking medications that would significantly interact with tDCS effects (such as sodium channel blockers or anticonvulsants) - Neurological disorders (e.g., dementia, stroke, seizures, traumatic brain injury, Parkinson's disease) - Montreal Cognitive Assessment (MoCA) score < 23 - Primary amnestic cognitive profile (>1.5 standard deviations (SDs) below demographically-adjusted mean on National Alzheimer's Coordinating Center (NACC) memory measures in context of otherwise normal cognitive profile) - Any physical or intellectual disability affecting ability to complete assessments - Unstable medical illness needing urgent treatment - MRI contraindications - Electroconvulsive therapy (ECT) or transcranial magnetic stimulation (TMS) in last 2 months - Current involvement in psychotherapy - Current involvement in other research studies (including but not limited to: neuromodulation [TMS or tDCS] or investigational drug studies)

Study Design

Phase
N/A
Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel Assignment
Primary Purpose
Treatment
Masking
Double (Participant, Investigator)
Masking Description
Double-blind

Arm Groups

ArmDescriptionAssigned Intervention
Experimental
Cognitive Training + Active Stimulation
This arm receives cognitive training combined with active tDCS.
  • Behavioral: Cognitive Training
    Computerized cognitive training targeting the underlying cerebral networks associated with depression.
  • Device: tDCS (active stimulation)
    A Soterix Clinical Trials Direct Current Stimulator will apply 20 minutes of 2.0 milliamps (mA) direct current through two bicarbon rubber electrodes encased in saline soaked 5 cm x 7 cm sponges (8 cc of 0.9% saline solution per sponge) placed over the frontal cortices at F3 and F4 (via 10-20 system).
Experimental
Cognitive Training + Sham Stimulation
This arm receives cognitive training combined with sham tDCS.
  • Behavioral: Cognitive Training
    Computerized cognitive training targeting the underlying cerebral networks associated with depression.
  • Device: tDCS (sham stimulation)
    Sham stimulation will be performed with the same device and all procedures will be identical except for the duration of stimulation. Participants will receive 30 seconds of 2 mA of direct current stimulation at the beginning of the session. Participants habituate to the sensation of tDCS within 30-60 seconds of stimulation. This procedure provides the same sensation of tDCS without the full duration of stimulation, making it a highly effective sham procedure.

Recruiting Locations

Vanderbilt University Medical Center
Nashville, Tennessee 37212
Contact:
Sarah M Szymkowicz, PhD
615-875-0032
sarah.szymkowicz@vumc.org

More Details

Status
Recruiting
Sponsor
Vanderbilt University Medical Center

Study Contact

Sarah M. Szymkowicz, PhD
615-875-0032
sarah.szymkowicz@vumc.org

Detailed Description

The purpose of this study is to determine whether the addition of active tDCS to computerized cognitive remediation (nCCR) enhances brain activity and cognitive functions in older adults with recurrent depression to a greater degree than nCCR with sham stimulation. The investigators will randomize 20 elderly depressed outpatients to either double-blinded active or sham bifrontal tDCS plus daily nCCR over 4-weeks. Multimodal MRI (focused on the cognitive control network; CCN) and psychiatric and neuropsychological evaluations will be obtained at baseline and following intervention completion. Long-term CCN cognitive effects will be explored 3-months post-intervention via cognitive assessments.