Short-term memory binding deficits in Alzheimer’s disease

Memory load was increased for the healthy elderly group to eight items in the conditions assessing memory for single or unbound features and to four items in the condition assessing memory for the binding of these features. For Alzheimer’s disease patients the task remained the same. This manipulation permitted the performance to be equated across groups in the conditions assessing memory for single or unbound features. The impairment in Alzheimer’s disease patients in recalling bound objects reported in Experiment 1 was replicated. The binding cost was greater than that observed in the healthy elderly group, who did not differ in their performance for bound and unbound features. Alzheimer’s disease grossly impairs the mechanisms responsible for holding integrated objects in verbal short-term memory

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Longitudinal study of single-word comprehension in semantic dementia: A comparison with primary progressive aphasia and Alzheimer’s disease

Conclusions: These results indicate that category-specific deficits of single-word comprehension are frequently seen not only in patients with SD but also in individuals with PPA or AD, and that the extent of these deficits is associated with the severity of aphasia. However, the pattern of these deficits is often different in these three forms of neurodegenerative conditions and more dissociations between semantic categories are observed as each of these diseases progresses.

from Aphasiology

Persistence of self in individuals with Alzheimer’s disease

The persistence of self in individuals with probable Alzheimer’s disease was investigated via language and visual self-recognition. Seventy-eight adults (ages 66—103) participated: 26 with mild cognitive impairments, 26 with moderate cognitive impairments, and 26 without impairment. Although frequency of language usage (during an interview) declined across impairment levels, there were no significant differences in either rates or proportions of pronoun and attribute usage. When asked to identify themselves in photographs taken with an instant camera, cognitively impaired individuals — in spite of forgetting the photographic session only minutes earlier — exhibited unimpaired self-recognition, a dissociation consistent with a preserved self. Taken together, these findings indicate a persistence of self in individuals with dementia, and have implications for how Alzheimer’s is characterized and experienced, and how individuals are cared for.

from Dementia

Stage-Independent and Stage-Specific Phenotypic Differences between Vascular Dementia and Alzheimer’s Disease

Aims: We examined the effect of stratification by dementia severity on clinical and neuropsychological differences observed between vascular dementia (VaD) and Alzheimer’s disease (AD) to ascertain whether any observed phenotypic differences would differ between the early and late stages. Methods: The phenotypic features at presentation of 219 newly diagnosed VaD (n = 103) and AD (n = 116) patients were analyzed. All patients underwent clinical, neuropsychological and neuroimaging evaluation. Severity of dementia was staged using the Clinical Dementia Rating (CDR) scale. Results: VaD can be clinically distinguished from AD by criterion-related features that span across all stages of dementia. We also identified non-criterion-related features that differed according to dementia severity. In the CDR 0.5-1 stage, VaD patients demonstrated increased reading difficulty, loss of insight, apathy, and greater impairment in executive function compared with delayed and recognition memory. Unique distinguishing features for VaD in the CDR 2-3 stage included higher Geriatric Depression Scale scores, lower Barthel scores, gait apraxia and parkinsonism. Conclusions: Phenotypic differences between VaD and AD can be conceptualized as either criterion-related stage-independent features, or stage-specific features (comprising cognitive and neuropsychological elements in the mild stages, and physical, affective and functional components in the later stages).

from Dementia and Geriatric Cognitive Disorders

Collaborative role construction in a conversation with dementia: An application of systemic functional linguistics

This study applies the tools provided by Systemic Functional Linguistics (SFL) to the description of patterns in a conversation between a person with dementia and a person without. It shows how, in the presence of, on the one hand, considerable communicative and cognitive deficits, and on the other, a collaborative interlocutor, a person with dementia succeeds in leading and sustaining a lengthy conversation, and of constructing for himself a positive role in the interaction, namely that of the elder advising a much younger man.

from Clinical Linguistics and Phonetics

How Do Verbal Distractors Influence Age-Related Operation Span Performance? A Manipulation of Inhibitory Control Demands

from Experimental Aging Research

This study examined how different verbal distractors influence (age-related) performance in the operation span working memory task. Forty-six older (M = 68 years, SD = 3.82) and 49 younger adults (M = 27 years, SD = 3.02) performed a conventional operation span task version and three versions with non-related, conceptually related, or phonologically related distracting words. Thus, the amount of inhibitory control demands varied across the task versions. Age effects were found for all versions. Furthermore, age effects in the versions with distracting words were even larger than in the conventional version, indicating that a decline in the ability to inhibit irrelevant verbal information can partly explain age effects in working memory performance.

Clustering and switching processes in semantic verbal fluency in the course of Alzheimer’s disease subjects: Results from the PAQUID longitudinal study

from Cortex

Abstract
Reduced semantic fluency performances have been reported in the preclinical phase of Alzheimer’s disease (AD). To investigate the cognitive processes underlying this early deficit, this study analyzed the verbal production of predemented subjects for the animals category with the qualitative parameters related to clustering (i.e. the ability to generate words belonging to semantic subcategories of animals) and switching (i.e. the ability to shift from one subcategory to another) proposed by Troyer.

This qualitative analysis was applied to the PAQUID (Personnes Agées QUID) cohort, a 17-year longitudinal population-based study. The performances on the animal verbal fluency task of 51 incident cases of possible and probable AD were analyzed at the onset of dementia, 2 years and 5 years before dementia onset. Each case was matched for age, sex and education to two control subjects leading to a sample of 153 subjects. The mean cluster size and the raw number of switches were compared in the two samples. The results revealed a significantly lower switching index in the future AD subjects than in the elderly controls including 5 years before dementia incidence. A significant decline in this parameter was evidenced all along the prodromal phase until the clinical diagnosis of dementia. In contrast, the mean cluster size could not discriminate the two groups. Therefore the results support the hypothesis that impaired shifting abilities – rather than semantic memory storage degradation – could explain the early decline in semantic fluency performance occurring in the predementia phase of AD.

The impact of dementia, age and sex on category fluency: Greater deficits in women with Alzheimer’s disease

from Cortex

A category specific effect in naming tasks has been reported in patients with Alzheimer’s dementia. Nonetheless, naming tasks are frequently affected by methodological problems, e.g., ceiling effects for controls and “nuisance variables” that may confound results. Semantic fluency tasks could help to address some of these methodological difficulties, because they are not prone to producing ceiling effects and are less influenced by nuisance variables. One hundred and thirty-three participants (61 patients with probable AD; and 72 controls: 36 young and 36 elderly) were evaluated with semantic fluency tasks in 14 semantic categories. Category fluency was affected both by dementia and by age: while in nonliving-thing categories there were differences among the three groups, in living thing categories larger lexical categories produced bigger differences among groups. Sex differences in fluency emerged, but these were moderated both by age and by pathology. In particular, fluency was smaller in female than male Alzheimer patients for almost every subcategory.

Drug Restores Speech in Alzheimer’s

from Newsmax.com

Alzheimer’s patients given a popular rheumatoid arthritis drug showed seemingly dramatic improvements in a small study, but some doctors worried that the early findings will raise premature hopes in patients and their families.

Are Age Differences in Verbal Learning Related to Interstimulus Interval and Education?

from Experimental Aging Research

Abstract
The present study investigated the effects of a narrow range of interstimulus intervals (ISI; 1, 2, or 3 s) on word-learning performance in relation to age and education. Individuals (N = 338) from four age groups (24 to 76 years) with low or high educational attainment were randomly assigned to one of three ISI conditions. Older age, lower education, and shorter ISI each led to lower performance. However, age differences in performance were not affected by ISI. Furthermore, lower educated individuals needed more time to achieve the same performance level as higher educated individuals.

Collaborative role construction in a conversation with dementia: An application of systemic functional linguistics

from Clinical Linguistics and Phonetics

This study applies the tools provided by Systemic Functional Linguistics (SFL) to the description of patterns in a conversation between a person with dementia and a person without. It shows how, in the presence of, on the one hand, considerable communicative and cognitive deficits, and on the other, a collaborative interlocutor, a person with dementia succeeds in leading and sustaining a lengthy conversation, and of constructing for himself a positive role in the interaction, namely that of the elder advising a much younger man.

Language, Culture Barriers Affect Early Alzheimer’s Diagnosis Among Hispanics

from Topix.net

Language and cultural barriers cause a significant number of elderly Hispanics with Alzheimer’s disease to remain undiagnosed and untreated, experts say, the Newark Star-Ledger reports.

Central Auditory Dysfunction in Older Persons With Memory Impairment or Alzheimer Dementia

from Archives of Otolaryngology–Head and Neck Surgery

Objective To assess the effect of memory impairment on central auditory function.

Design Case-control study.

Setting The Virginia Merrill Bloedel Hearing Research Center, Seattle, Washington.

Participants The study cohort of 313 volunteers from a dementia surveillance research program comprised 3 groups: (1) controls without memory loss (n = 232); (2) memory-impaired participants with mild memory impairment but without dementia (n = 64); and (3) memory-impaired participants with a dementia diagnosis (n = 17).

Main Outcome Measures Behavioral central auditory tests were the Synthetic Sentence Identification with Ipsilateral Competing Message test, the Dichotic Sentence Identification test, and the Dichotic Digits Test. Memory impairment was indicated by a total score on the Cognitive Ability Screening Instrument of 86 or less, or a total score of 90 or less with a memory subscale score of 10 or less.

Results The mean score on each central auditory test worsened significantly across the 3 memory groups even after adjustment for age and peripheral hearing status (P<.05); it was poorest in the dementia group and moderately reduced in the memory-impaired group compared with the control group. Heterogeneity of results was noted in all 3 groups.

Conclusions Central auditory function was affected by even mild memory impairment. The Dichotic Sentence Identification test in the free report mode was the most sensitive test for the presence of memory impairment. We recommend that central auditory testing be considered in the evaluation of older persons with hearing complaints as part of a comprehensive, individualized program to assist their needs in both the aural rehabilitative and the cognitive domains.

Rapid improvement in verbal fluency and aphasia following perispinal etanercept in Alzheimer’s disease

from BMC Neurology

Background
Recent clinical studies point to rapid and sustained clinical, cognitive, and behavioral improvement in both Alzheimer’s disease and primary progressive aphasia following weekly perispinal administration of etanercept, a TNF-alpha inhibitor that acts by blocking the binding of this cytokine to its receptors. This outcome is concordant with recent basic science studies suggesting that TNF-alpha functions in vivo as a gliotransmitter that regulates synaptic function in the brain. We hypothesized that perispinal etanercept had the potential to improve verbal function in Alzheimer’s disease, so we included several standarized measures of verbal ability to evaluate language skills in a clinical trial of perispinal etanercept for Alzheimer’s disease.

Methods
This was a prospective, single-center, open-label, pilot study, in which 12 patients with mild-to-severe Alzheimer’s disease were administered etanercept, 25-50 mg, weekly by perispinal administration for six months. Two additional case studies are presented.

Results
Two-tailed, paired t-tests were conducted comparing baseline performance to 6-month performance on all neuropsychological measures. Test batteries included the California Verbal Learning Test-Second Edition, Adult Version; Logical Memory I and II(WMS-LM-II) from the Wechsler Memory Scale-Abbreviated; the Comprehensive Trail Making Test (TMT); Boston Naming Test; and letter(FAS) and category verbal fluency. All measures revealed a significant effect except for the Boston Naming Test and the TMT-4, with WMS-LM-II being marginally significant at p=.05. The FAS test for letter fluency was most highly significant with a p<0.0007. In addition, rapid improvement in verbal fluency and aphasia in two patients with dementia, beginning minutes after perispinal etanercept administration, is documented.

Conclusions
In combination with the previously reported results of perispinal etanercept in Alzheimer’s disease and primary progressive aphasia, these results further argue that larger scale studies of this therapeutic intervention, including Phase 3 trials, are warranted in dementias. In addition, these results may provide insight into the basic pathophysiologic mechanisms underlying Alzheimer’s disease and related forms of dementia, and suggest the existence of novel, rapidly reversible, TNF-mediated pathophysiologic mechanisms in Alzheimer’s disease which are worthy of further investigation.

Central Auditory Dysfunction in Older Persons With Memory Impairment or Alzheimer Dementia

from Archives of Otolaryngology–Head and Neck Surgery

Objective To assess the effect of memory impairment on central auditory function.

Design Case-control study.

Setting The Virginia Merrill Bloedel Hearing Research Center, Seattle, Washington.

Participants The study cohort of 313 volunteers from a dementia surveillance research program comprised 3 groups: (1) controls without memory loss (n = 232); (2) memory-impaired participants with mild memory impairment but without dementia (n = 64); and (3) memory-impaired participants with a dementia diagnosis (n = 17).

Main Outcome Measures Behavioral central auditory tests were the Synthetic Sentence Identification with Ipsilateral Competing Message test, the Dichotic Sentence Identification test, and the Dichotic Digits Test. Memory impairment was indicated by a total score on the Cognitive Ability Screening Instrument of 86 or less, or a total score of 90 or less with a memory subscale score of 10 or less.

Results The mean score on each central auditory test worsened significantly across the 3 memory groups even after adjustment for age and peripheral hearing status (P<.05); it was poorest in the dementia group and moderately reduced in the memory-impaired group compared with the control group. Heterogeneity of results was noted in all 3 groups.

Conclusions Central auditory function was affected by even mild memory impairment. The Dichotic Sentence Identification test in the free report mode was the most sensitive test for the presence of memory impairment. We recommend that central auditory testing be considered in the evaluation of older persons with hearing complaints as part of a comprehensive, individualized program to assist their needs in both the aural rehabilitative and the cognitive domains.