Cognitive Enhancement in Depression (The COG-D Study)

Eligibility 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
• * 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)