Selective Naming (and Comprehension) Deficits in Alzheimer's Disease (original) (raw)
Related papers
Is action naming better preserved (than object naming) in Alzheimer’s disease and why should we ask
Brain and Language, 2006
The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are aVected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose diVerent demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.
Object and Action Naming in Alzheimer's Disease
Cortex, 1998
We administered measures of object naming and action naming to matched groups of ten patients with Alzheimer's disease (AD) and ten normal control subjects. AD patients were impaired in both object and action naming, with object naming impaired to a significantly greater extent than action naming. This difference remained after controlling for the effects of word frequency. We propose that the pattern of pathological changes in AD impairs both conceptual and lexical retrieval systems for objects but only conceptual systems for actions. The similar patterns of error during the two tasks suggest quantitative rather than qualitative differences in the breakdown of the two abilities.
A common mechanism in verb and noun naming deficits in Alzheimer’s patients
Brain and Language, 2009
We tested the ability of Alzheimer's patients and elderly controls to name living and non-living nouns, and manner and instrument verbs. Patients' error patterns and relative performance with different categories showed evidence of graceful degradation for both nouns and verbs, with particular domain-specific impairments for living nouns and instrument verbs. Our results support feature-based, semantic representations for nouns and verbs and support the role of inter-correlated features in noun impairment, and the role of noun knowledge in instrument verb impairment.
Selective Sparing of Verb Naming in a Case of Severe Alzheimer's Disease
1999
A patient with severe Alzheimer's disease (AD) presented with a severe impairment in naming nouns but selective sparing of the naming of verbs. Her impairment in naming nouns was presented across a wide range of categories investigated. To our knowledge, this is the first case documenting the selective preservation of verb naming in a patient with AD. The implications for the notion of an intrinsic vulnerability of verb naming in AD and for the current knowledge of anatomical correlates of noun/verb processing are discussed.
Clinics (São Paulo, Brazil), 2015
Naming deficit is a linguistic symptom that appears in the initial phase of Alzheimer's disease, but the types of naming errors and the ways in which this deficit changes over the course of the disease are unclear. We analyzed the performance of patients with Alzheimer's disease on naming tasks during the mild and moderate phases and verified how this linguistic skill deteriorates over the course of the disease. A reduced version of the Boston Naming Test was administered to 30 patients with mild Alzheimer's disease, 30 patients with moderate Alzheimer's disease and 30 healthy controls. Errors were classified as verbal semantic paraphasia, verbal phonemic paraphasia, no response (pure anomia), circumlocution, unrelated verbal paraphasia, visual errors or intrusion errors. The patients with moderate Alzheimer's disease had significantly fewer correct answers than did both the control group and the group with mild Alzheimer's disease. With regard to the pattern...
Effects of Semantic Impairment on Language Use in Alzheimer's Disease
Seminars in Speech and Language, 2008
Many studies present apparently conflicting results and conclusions about the effects of Alzheimer's disease (AD) on language use. This review attempts to reconcile these apparently conflicting results regarding the language impairments in AD by discussing how the slow deterioration of the semantic system at the feature level interacts with the task demands of tests used to evaluate performance. In particular, performance is impaired on tasks that require relatively complete, elaborate semantic representations but is preserved when the task requires only partial semantic representations consisting largely of shared features. The variety of language impairments reported in complex, multiword tasks are likely attributable to a combination of the deterioration of semantic representations and reduced working memory resources. The few available treatment studies for language impairments in AD suggest that treatments designed for adults with other language impairments, such as aphasia, may also be effective in AD.
Analysis of naming processing stages in patients with mild Alzheimer
Applied Neuropsychology: Adult, 2019
In the evaluation of the nature of naming disorders, there is a rapid increase of anomia with the progression of Alzheimer's disease (AD), which is associated with whole brain atrophy. Although numerous studies have investigated this naming disorder, there is limited information on naming procedures in these patients. Reaction time (RT) is highly sensitive to dementia and provides an accurate measurement. The present study investigated the RT of each underlying level of naming in patients with mild AD and identified the nature of anomia in these patients. The study consisted of 24 healthy elderly and 22 mild AD patients who participated in experiments that were designed for evaluating each level of Levelt's model. Responses were divided into three groups of correct, false, and no-response and their RTs were calculated. The statistical analyses showed significant differences between healthy elderly and patients with mild AD in terms of access to the concept and the phonological form of the words. Moreover, significant differences in the type of responses were observed between correct and false responses of both groups. There was a significant difference between the no-response cases except in the case of lemma access for singular and plural names in other tasks. The results suggest that patients with mild AD have problems at the conceptual stage and access to the phonological form of a word.
The nature of lexical-semantic impairment in Alzheimer's disease
Journal of Neurolinguistics, 1989
Semantic-lexical disorders of Alzheimer's disease (AD) patients have been considered by various authors as resulting either from a loss of information or from an inability to access an intact semantic representation. Since consistency of errors over the same items is usually considered as a proof of the "loss of information" hypothesis, 15 AD patients and 10 age-matched normal controls received a confrontation naming task and a "verbal associates recognition" task, constructed using the same set of stimuli. For each stimulus to be named, the patient received a list of associates, belonging todifferent associative categories (superordinate, part of whole, attribute, function associate, functional context and contrast coordinate); his task consisted in judging if the word was or was not related to the target. The working hypothesis was that, if naming errors of demented patients are due to a loss of information in the semantic representation of the not-named items, then these patients should perform worse with the semantic associates of the not-named than with those of the correctly named items. Results confirmed the hypothesis in AD patients with moderate anomia, showing that, in the early stages of the dementia1 dissolution, naming errors can be-traced back to a loss of information at the level of the semantic representation subtending the misnamed items.
Neurocase, 2010
Accumulating evidence indicates action naming may rely more on frontal-subcortical circuits, and noun naming may rely more on temporal cortex. Therefore, noun versus action fluency might distinguish frontal and subcortical dementias from cortical dementias primarily affecting temporal and/or parietal cortex such as Alzheimer's disease (AD). We hypothesized patients with subcortical dementia, e.g., normal pressure hydrocephalus (NPH) and patients with dementias predominantly affecting frontal cortex, e.g., behavioral variant frontotemporal dementia (bv-FTD) and progressive nonfluent aphasia (PNFA) have more difficulty on action fluency versus noun fluency (e.g., animal naming). Patients with AD, who have temporo parietal cortical dysfunction, should have more difficulty on noun versus verb fluency. A total of 234 participants, including healthy controls (n = 20) and patients diagnosed with NPH (n =144), AD (n = 33), bv-FTD (n = 22) or PNFA (n =15) were administered animal fluency, action fluency, and letter fluency tasks, and the Mini-Mental State Examination (MMSE, to control for dementia severity). NPH and bv-FTD/PNFA patients had significantly higher MMSE scores and animal fluency than AD patients (after adjusting for age), but their action fluency tended to be lower than in AD. Only NPH and bvFTD/PNFA patients showed significantly lower action verb than animal fluency. Results provide novel evidence that action naming relies more on frontal-subcortical circuits while noun naming relies more on temporoparietal cortex, indicating action verb fluency may be more sensitive than noun fluency, particularly for detecting frontal-subcortical dysfunction.