Inclusion Criteria:
- 19-55 years old
- Meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for MDD as assessed by a standardized psychiatric interview (SCID-5-RV) conducted by a trained clinician.
- Patients will be euthymic or mildly depressed (defined by a Montgomery-Asberg Depression Rating Scale \[MADRS\] score < 19)
- Patients will report subjective cognitive deficits at baseline, as indicated by a total Perceived Deficits Questionnaire - Depression 20 \[PDQ-D-20\] score > 20 at study enrollment.
- If using antidepressants, participants will be on stable antidepressant therapy for at least 4 weeks prior to randomization. All concomitant doctor-prescribed medications must be at a stable dose for 4 weeks prior to the randomization visit.
- If undergoing psychotherapy, participants will be on stable adjunct psychotherapy for at least 8 weeks prior to randomization
- If comorbid diagnosis of attention deficit hyperactivity disorder (ADHD), patients must be on stable dose of stimulants for at least 4 weeks prior to randomization.
- Participants will be able to follow written and verbal instructions in English
Exclusion Criteria:
- Moderate - severely depressed patients will be excluded at this point due to acceptability concerns (e.g. potential for cybersickness)
- Presence of significant neurological disorders, head trauma, or other unstable medical conditions. These conditions may adversely impact cognitive functioning and influence study results.
- Presence of other psychiatric disorder (e.g. anxiety, psychotic disorder) that may be considered primary.
- Meeting DSM-5 criteria for alcohol or other substance use disorder within three months prior to the randomization visit.\*
- Use of benzodiazepine medications more than three times per week and/or within 24 hours of baseline or close out visit
- Use of cannabis or alcohol within 24 hours, or tobacco within 30 minutes of baseline or close out visit
- Suicidal ideation or self harm
- Completion of previous cognitive remediation
Additionally, patients will be excluded from the study if they meet any of the following criteria due to contraindications with MRI scanning:
- Retained wires from an electronic implant that has been removed (i.e. pacemaker wires not attached to a pacemaker)
- Cardiac pacemaker or defibrillator
- Metal in eye or orbit
- Ferromagnetic aneurysm clip
- Pregnancy
- Makeup tattoos that are not designed to fade over time
- Stainless steel intrauterine device (IUD)
Depending on the individual situation, they MAY NOT be able to participate if they have/had any of the following:
- Artificial Heart Valve
- Ear or eye implant
- Brain aneurysm clip
- Implanted electronic device (i.e. drug infusion pump, electrical stimulator)
- Coil, catheter, or filter in any blood vessel
- Orthopedic hardware (artificial joint, plate, screw, rod)
- Shrapnel, bullets, or other metal fragments
- Surgery, medical procedure or tattoos (including tattooed eyeliner) in the last six weeks
- Other metallic prostheses
If the participant has any of the above, or any safety issues arise during MRI screening process, the individual case will be reviewed by UBC Hospital MR Technologist and/or Radiologist and a case-by-case decision will be made regarding participation.
Additionally, for the healthy participant recruitment, the eligibility criteria is as follows:
Inclusion Criteria for healthy controls:
\- 19-55 years old
Exclusion criteria for healthy controls:
- History of any psychiatric disorder, as assessed by a standardized psychiatric diagnostic interview
- Presence of significant neurological disorder, head trauma, or other unstable medical conditions which may adversely impact cognitive functioning
- Presence of any physical mobility issues that limit arm or neck movement