Lost in Space and Thought: Navigating the Cognitive Map in Alzheimer's Disease

Spatial navigation is one of the brain's most fundamental abilities, enabling us to move through the world with ease. The seemingly effortless act of navigation depends on complex cognitive functions, with the cognitive map playing a central role. In individuals with Alzheimer's disease (AD) and mild cognitive impairment (MCI), however, this once intuitive ability becomes disoriented and impaired before the emergence of noticeable memory symptoms. AD pathology disrupts structural and functional disabilities in the brain's navigation system, resulting in cognitive map-based navigational difficulties. These deficits affect not only physical navigation but also extend into abstract, knowledge-based domains. In this review, we explore the role of cognitive map dysfunction in the navigation impairments seen in AD, synthesizing current evidence from studies of both spatial and non-spatial deficits. These insights may deepen our knowledge of how the brain navigates and also offer promising avenues for predictive biomarkers and targeted interventions.