Semantic dementia: a unique clinicopathological syndrome.
Semantic dementia (SD), one of the main clinical variants of frontotemporal dementia, presents a unique combination of clinical and imaging abnormalities. We describe the epidemiological, cognitive, and radiological features of SD. The distinctive and consistent neuropsychological deficits in this disorder have had a major effect on current conceptions of the organisation of semantic memory and its links to episodic memory, language, and perceptual processes. Structural (MRI) and functional (fluorodeoxyglucose-PET) studies in SD emphasise the role of the temporopolar and perirhinal cortices. Unlike other frontotemporal dementia syndromes, the neuropathological findings in SD are fairly predictable: most patients have ubiquitin-positive, tau-negative neuronal inclusions.
Hodges
John R
JR
Prince of Wales Medical Research Institute, University of New South Wales, Sydney, Australia. john.hodges@mrc-cbu.cam.ac.uk
Patterson
Karalyn
K
D003704:Dementia / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology*; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008568:Memory; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D013702:Temporal Lobe / Q000473:pathology / Q000503:physiopathology; D014705:Verbal Behavior