Pattern Separation in Major Depressive Disorder

11 weeks of open-label treatment with an SSRI, of which the last 6 weeks are augmented with memantine vs placebo. Primary SSRI for the study is escitalopram. In cases of prior intolerance or non-response to escitalopram, individuals will be treated with sertraline instead of escitalopram.

6 weeks of treatment with extended-release memantine as augmentation to ongoing escitalopram treatment

6 weeks of treatment with placebo as augmentation to ongoing escitalopram treatment