Semantic dementia: a unique clinicopathological syndrome
The Lancet NeurologyPublished 1 November 2007
John R. Hodges, Karalyn Patterson
Citations772
SJR quartileQ1
SJR score11.73
SNIP13.75
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TL;DR
The epidemiological, cognitive, and radiological features of semantic dementia are described and structural and functional studies in SD emphasise the role of the temporopolar and perirhinal cortices.
Abstract
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.
Keywords
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The results support the view that new episodic learning typically draws on information from both perceptual and semantic systems, and confirm good recognition memory for famous faces, even if semantic knowledge about the celebrities depicted was severely degraded.
Journal of Cognitive NeuroscienceLongitudinal Profiles of Semantic Impairment for Living and Nonliving Concepts in Dementia of Alzheimer's Type
99 Citations2001Peter Garrard, Matthew A. Lambon Ralph +4 more
Findings from two separate cohorts of patients with probable dementia of Alzheimer's type are interpreted as evidence for the importance of regional cerebral anatomy to the genesis of semantic domain effects in DAT.
European Journal of NeuroscienceAssociative and recognition memory for novel objects in dementia: implications for diagnosis
98 Citations2003Andy Lee, Shibley Rahman +3 more
Findings confirm that tests of episodic memory, especially for the location of objects in space, may be useful in the early diagnosis and differentiation of dementia of the Alzheimer's type.
International Journal of Geriatric PsychiatryPatterns of autobiographical memory loss in dementia
97 Citations2005Craig E. Hou, Bruce L. Miller +1 more
Several studies have found impaired recall of remote autobiographical memories relative to recent memories in semantic dementia (SD), a pattern opposite to that in Alzheimer's disease (AD).
Cognitive NeuropsychologySEMANTIC DEMENTIA WITH CATEGORY SPECIFICITY:ACOMPARATIVE CASE-SERIES STUDY
96 Citations2003Matthew A. Lambon Ralph, Karalyn Patterson +2 more
Patients with semantic dementia, the temporal variant of frontotemporal dementia, are relevant to both the neuroanatomical and neuropsychological debates in the category-specific literature, as well as to four accounts of category specificity: the sensory-functional theory, domain-specific knowledge systems, intercorrelated features, and individual differences.
CortexRepeat and Point: Differentiating semantic dementia from progressive non-fluent aphasia
80 Citations2007John R. Hodges, Marina Martinos +3 more
The Repeat and Point test is particularly appropriate for routine use in a clinical context because it is quick and easy to administer and score; it reliably discriminated between the two patient groups, SD and PNFA; and it offers a simple rule of thumb, i.e., the Repeat-to-Point ratio, to aid in the diagnosis of these two language variants of frontotemporal dementia (FTD).
CortexSentence Processing in Frontotemporal Dementia
75 Citations2005Murray Grossman, Jina Rhee +1 more
It is concluded that grammatical and executive components both contribute to sentence comprehension, and that the profile of sentence comprehension difficulty varies across FTD subgroups depending on the sentence processing component that is impaired.
Journal of Neurology Neurosurgery & PsychiatryThe prevalence of frontal variant frontotemporal dementia and the frontal lobe syndrome in a population based sample of 85 year olds
73 Citations2003Þorsteinn Gíslason
The prevalence of fvFTD was 3% in 85 year olds, which is higher than previously expected in this age group, and only a minority of those with fv FTD were detected by the DSM-III-R criteria for dementia.
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