ABSTRACT
The syndrome of semantic dementia (SD), relatively recently described, continues to enjoy a rapid growth in interest among clinicians and neuropsychologists. This chapter aims to give a concise overview of our current knowledge of the condition, as well as highlighting areas of controversy and active research. After giving a brief account of the historical context, we will begin by outlining the characteristic clinical features which suggest a diagnosis of SD. The following section will take a more detailed look at the deficits from a neuropsychological point of view, starting with the specifically languagerelated problems. We will then address the question of semantic deficits in non-verbal tasks, a controversial issue which has direct bearing on the place of SD among progressive aphasia and other dementia syndromes. Our knowledge of the localization of brain atrophy in SD has increased considerably with the recent development of increasingly sophisticated techniques of imaging analysis, and we will review the current state of the literature in this area. Finally, we will conclude by discussing the variety of post-mortem pathological findings in cases of SD, and the impact of these on its classification as a neurodegenerative disease.
