Developmental Topographical Disorientation, also known as DTD, is caused by the inability to segregate landmarks and derive navigational information from them, navigate through a non-verbal process, or generate cognitive maps. This is a newly discovered cognitive disorder in which patients who do not have brain structural abnormalities, such as lesions, and exhibit symptoms since childhood. Not to be confused with healthy individuals who have a poor sense of direction, DTD patients get lost in very familiar surroundings, such as their house or neighborhood, daily. This disorder could stem from a lack of experience in navigation during development and could present in different degrees of severity.
A woman in Vancouver, referred to as Pt1, presented with topographical disorientation in absence of any structural lesions. Despite normal cognitive development, she has never been able to orient with in the environment. Further testing showed that she was able to follow route based, landmark based, and verbal directions to reach a destination in an urban environment. In map based testing, the patient was unable to determine the shortest path between two locations on a map, but was able to follow a route traced on a map. The patient was unable to draw a detailed schematic of her house. Although the number of rooms and their locations were accurate, the spatial scaling was distorted.
The Daily Omnivore 
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