Of logos and men: semantic memory impairment for unique entities in a case of semantic variant of primary progressive aphasia.

In this study, an individual (NG) with the semantic varient of primary progressive aphasis (svPPA) was assessed with tasks designed to investigate the recognition and activation of semantic knowledge about unique entities. NG had significant difficulties in the recognition of brand names and famous names but was largely unimpaired in the recognition of logos and famous faces. However, she was impaired in tasks requiring the activation of semantic representations of logos, brand names, famous faces, and famous names. These results suggest that the recognition of unique entities results from the interaction of perceptual and conceptual processes and, that the ability to activate semantic information about these entities can be affected in svPPA.