Anomia: A doubly typical signature of semantic dementia

@article{Woollams2008AnomiaAD,
  title={Anomia: A doubly typical signature of semantic dementia},
  author={Anna M. Woollams and Elisa Cooper-Pye and John R. Hodges and Karalyn Patterson},
  journal={Neuropsychologia},
  year={2008},
  volume={46},
  pages={2503-2514}
}
This study was designed to explore the nature of the anomia that is a defining feature of semantic dementia. Using a pool of 225 sets of picture naming data from 78 patients, we assessed the effects on naming accuracy of several characteristics of the target objects or their names: familiarity, frequency, age of acquisition and semantic domain (living/non-living). We also analysed the distribution of different error types according to the severity of the naming deficit. A particular focus of… Expand
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References

SHOWING 1-10 OF 53 REFERENCES
Naming in semantic dementia—what matters?
TLDR
It is proposed that object familiarity, and possibly word frequency, reflect the inherent robustness of individual semantic representations to the decay process in terms of both quantity and quality of experience, and is suggested that age-of-acquisition and word frequency predicts naming success. Expand
No Right to Speak? The Relationship between Object Naming and Semantic Impairment:Neuropsychological Evidence and a Computational Model
TLDR
It is proposed that semantic impairment alone can account for the full range of word production deficits described here, on the basis of both the neuropsychological and computational evidence. Expand
Presemantic Cognition in Semantic Dementia: Six Deficits in Search of an Explanation
On the basis of a theory about the role of semantic knowledge in the recognition and production of familiar words and objects, we predicted that patients with semantic dementia would reveal aExpand
Knowledge of famous faces and names in semantic dementia.
TLDR
The findings of an examination of famous face and name knowledge in patients with semantic dementia are interpreted as inconsistent with a unitary, amodal model of semantic memory, and lead to argue that the focal syndrome of progressive prosopagnosia is one of the clinical presentations of semantic dementia and not a separate clinical entity. Expand
Charting the progression in semantic dementia: implications for the organisation of semantic memory.
Abstract A patient, JL, with the syndrome of semantic dementia was assessed longitudinally over a two-year period. The data presented here address the controversy concerning the hierarchicalExpand
A duck with four legs: Investigating the structure of conceptual knowledge using picture drawing in semantic dementia
TLDR
There was a significant effect of feature distinctiveness on the proportions of these error types: Intruded features were most likely to come from the pool of properties that are shared across domain. Expand
Is a Picture Worth a Thousand Words? Evidence from Concept Definitions by Patients with Semantic Dementia
TLDR
Nine patients with semantic dementia were asked to define concrete concepts either from presentation of a picture of the object or from its spoken name, and the results lead to a model of the semantic system that is divided by attribute type but not by modality. Expand
SEMANTIC DEMENTIA WITH CATEGORY SPECIFICITY:ACOMPARATIVE CASE-SERIES STUDY
TLDR
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. Expand
Semantic dementia and fluent primary progressive aphasia: two sides of the same coin?
TLDR
These findings support a claim that the patients' deficits on both verbal and non-verbal tasks reflect progressive deterioration of an amodal integrative semantic memory system critically involving the rostral temporal lobes, rather than a combination of atrophy in the left language network and a separate bilateral ventrotemporal-fusiform network. Expand
The Selective Impairment of Semantic Memory
  • E. Warrington
  • Psychology, Medicine
  • The Quarterly journal of experimental psychology
  • 1975
TLDR
Evidence is presented that this impairment of semantic memory cannot be accounted for by intellectual impairment, sensory or perceptual deficits, or expressive language disorder, and some tentative evidence for the structural basis for a hierarchically organized modality-specific semantic memory system is discussed. Expand
...
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