Preserved knowledge maps of countries: Implications for the organisation of semantic memory

We describe two patients with selectively preserved knowledge of the category of countries. Following a series of cerebra infarcts, patient DB presented with severe perceptual impairment, including dense apperceptive agnosia, prosopagnosia, an topographical agnosia. Despite these deficits, he could effortlessly name countries from their outline maps. Patient WH, who suffered from semantic dementia, had severe naming and comprehension difficulties, with extremely sparse residual semantic knowledge. Remarkably, the category of countries was preserved. First, we argue that, for both patients, this category preservation occurs at a semantic level. Second, we discuss our findings in the context …