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Semantic dementia

Synonym(s) Semantic primary progressive aphasia
Semantic variant PPA
Prevalence -
Inheritance Multigenic/multifactorial
or Not applicable
Age of onset Adult
  • G31.0
  • C0338462
MeSH -
MedDRA -


Disease definition

Semantic dementia (SD) is a form of frontotemporal dementia (FTD; see this term), characterized by the progressive, amodal and profound loss of semantic knowledge (combination of visual associative agnosia, anomia, surface dyslexia or dysgraphia and disrupted comprehension of word meaning) and behavioral abnormalities, attributable to the degeneration of the anterior temporal lobes.

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