Classification of navigation impairment: A systematic review of neuropsychological case studies

- Navigation impairment is often investigated in neuropsychological case studies.
- Current study provides a systematic inventory and interpretation of 58 case studies.
- We identified three main categories of navigation impairment.
- These categories are related to landmarks, locations, and paths.
- The model has implications for theory and clinical assessment of navigation ability.

The neurocognitive architecture of navigation ability has been investigated by extensively studying the navigation problems of individual neurological patients. These neuropsychological case reports have applied highly variable approaches to establish navigation impairment in their patients. This review provides a systematic and up-to-date inventory of all relevant case studies and presents an analysis of the types of navigation impairments that have been described. The systematic literature search revealed 58 relevant papers reporting on 67 neurological patients. Close analysis of their patterns of navigation performance suggests three main categories of navigation impairments. These categories are related to three types of representations that are considered highly relevant for accurate navigation: knowledge of landmarks, locations, and paths. The resulting model is intended to serve both clinical and theoretical advances in the study of navigation ability and its neural correlates.