Ing-Tsung Hsiao

1 INTRODUCTION Major depressive disorder (MDD) is a complex neuropsychiatric condition with far-reaching implications for both mental and physical health. Existing neuroimaging research consistently indicates a diminished hippocampal volume in individuals with unipolar depression (Hickie et al., 2005). Hippocampal volume has been linked to domains of cognition such as processing speed, working memory, spatial navigation, and abstract reasoning (Hardcastle et al., 2020).

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Research Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/ana.26516. Abstract Objective The glymphatic system cleans amyloid and tau proteins from the brain in animal studies of Alzheimer's disease (AD).