The goal of this observational study is to validate the Creyos online cognitive assessment platform in individuals with mild cognitive impairment, or remitted major depressive disorder. The main objectives of this research are:

1. To confirm the feasibility of administering the Creyos cognitive battery to older adults with Mild Cognitive Impairment MCI) or Major Depressive Disorder in remission (rMDD).
2. To determine whether the Creyos battery can detect changes in cognition that are predictive of changes on paper-and-pencil neuropsychological testing ("gold standard") over up to five years.

Participants will complete both in-person neuropsychological testing yearly as well as the Creyos online battery quarterly for up to 5 years, to allow us to compare performance on these two batteries over time.

General Inclusion Criteria:

• Ability to read and communicate in English
• Availability of a study partner who has regular contact with the participant

General Exclusion Criteria:

• Lifetime DSM 5 diagnosis of schizophrenia, bipolar disorder, or OCD
• DSM 5 diagnosis of alcohol or other substance use disorder within the past 12 months
• High risk for suicide
• Significant neurological conditions (e.g. stroke, seizure disorder, MS)
• Unstable medical illnesses (e.g. uncontrolled diabetes mellitus or hypertension)
• Taking anticonvulsants or other psychotropic medication that may interfere with cognitive testing that cannot be safely tapered and discontinued
• Current depressive symptoms defined as a MADRS score of 10 or above

Specific Eligibility Criteria for the MCI Group:

Inclusion:

• Aged 60 or older
• Meets DSM 5 criteria for Minor Neurocognitive Disorder ("MCI")

Exclusion:

• Having taken a cognitive enhancer within the past 6 weeks

Specific Eligibility Criteria for the rMDD Group:

Inclusion:

• Aged 65 or older
• Meets DSM 5 criteria for one or more major depressive episode(s) (MDE) during their adult life (i.e. 18 years of age or older) with: (a) an offset of 2 months to 5 years from the screening visit date, or (b) an offset of 5 years or more, with at least one MDE receiving medical attention (e.g. previously been on an antidepressant, saw a psychiatrist, primary care physician, or had a previous hospitalization

Exclusion:

• Having taken a cognitive enhancer within the past 6 weeks
• Having received electroconvulsive therapy (ECT) within 6 months of baseline neuropsychological testing

Specific Eligibility Criteria for the Control Group:

Inclusion:

• Aged 60 or older

Exclusion:

• Meets DSM 5 criteria for MDD at anytime during their lifetime
• Meets DSM 5 criteria for Minor Neurocognitive Disorder ("MCI")

We will recruit participants with MCI, rMDD or controls in Toronto, Ontario, Canada who are available to come to the Centre for Addiction and Mental Health once per year for up to 5 years for in-person assessments