A progressive category-specific semantic deficit for non-living things

We report a longitudinal study of a patient, ES, with a progressive degener ative disorder resulting from generalised cerebral atrophy. Across a range of tasks, ES showed a greater difficulty in recognising and naming artifact s than living things. This deficit for artifacts emerged over time, as she became more severely impaired, in one task, picture naming, there was a cro ssover from an initial deficit for living things to the later artifact defi cit. All materials were carefully controlled to rule out potential confound ing factors such as concept familiarity or age of acquisition. There was no evidence that ES's deficit for artifacts was associated with a greater los s of functional than visual information. The pattern of results are consist ent with a recently proposed distributed connectionist model. in which a de ficit for artifact concepts can emerge as the result of severe, general dam age to semantic memory. (C) 1999 Elsevier Science Ltd. All rights reserved.