Topographical disorientation: Selective impairment of locomotor space?

We report a single-case study of a patient who suddenly lost her ability to orient herself in her neighbourhood. On formal testing she demonstrated remarkably selective deficits in episodic and semantic memory of topographical items and routes. Her general intellectual abilities were unaffected as were basic perceptual processes and episodic and semantic memory other than topography. We interpret her deficit as a further example of category-specific processing impairment affecting knowledge acquired through selective channels - in this case visuo-locomotor information.