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Background: Vocabulary scores increase until approximately age 65 years and then remain stable or decrease slightly, unlike scores on tests of other cognitive abilities that decline significantly with age., Aims: To review the findings on ageing-related changes in vocabulary, and to discuss four methodological issues: research design; test type; measurement; and vocabulary ability as a proxy for general intelligence., Main Contribution: A discussion of cross-sectional and longitudinal research designs shows that cohort membership accounts for some but not all ageing-related changes in vocabulary, and that drop-out and test-retest effects do not alter conclusions regarding these changes. Test type affects age trends in vocabulary, and if researchers use only one test, they should choose a multiple-choice synonym test. While some authors suggest that vocabulary tests do not measure the same underlying ability in younger and older adults, more research of this suggestion is needed. A brief examination of the use of vocabulary ability as a proxy for general intelligence in healthy ageing and for premorbid abilities in dementia indicates that such practice is often questionable., Conclusions: Vocabulary knowledge increases through the mid-60s regardless of measurement method. However, there is little information on how word knowledge serves other verbal skills in old age, how and when adults learn new words, or how much exposure is necessary for meanings to remain in storage for a lifetime. Research of these issues may require new methodologies, as well as novel theoretical accounts of ageing-related effects on vocabulary., What This Paper Adds: What is already known on this subject Unlike many cognitive abilities that decline with ageing, vocabulary knowledge continues to increase until approximately age 65, and then remains stable or decreases slightly. These findings have been replicated in different research designs and across languages. What this paper adds to existing knowledge The article presents a summary of findings on changes in vocabulary across adulthood, and a discussion of four key methodological issues: research design, test type, measurement, and the use of vocabulary ability as a proxy for general intelligence. What are the potential or actual clinical implications of this work? To better understand changes in vocabulary knowledge across adulthood, clinicians must be aware of methodological considerations that affect the field. Such considerations have direct clinical implications regarding the choice of vocabulary tests and their use as a proxy for other abilities in both healthy older adults and in individuals with dementia., (© 2022 The Authors. International Journal of Language & Communication Disorders published by John Wiley & Sons Ltd on behalf of Royal College of Speech and Language Therapists.)

Background: Glucocerebrosidase (GBA) gene mutations and APOE polymorphisms are common in dementia with Lewy bodies (DLB), however their clinical impact is only partially elucidated.Objective: To explore the clinical impact of mutations in the GBA gene and APOE polymorphisms separately and in combination, in a cohort of Ashkenazi Jewish (AJ) patients with DLB.Methods: One hundred consecutively recruited AJ patients with clinically diagnosed DLB underwent genotyping for GBA mutations and APOE polymorphisms, and performed cognitive and motor clinical assessments.Results: Thirty-two (32%) patients with DLB were carriers of GBA mutations and 33 (33%) carried an APOE ɛ4 allele. GBA mutation carriers had a younger age of onset (mean [SD] age, 67.2 years [8.9] versus 71.97 [5.91]; p = 0.03), poorer cognition as assessed by the Mini-Mental State Examination (21.41 [6.9] versus 23.97 [5.18]; p < 0.005), and more severe parkinsonism as assessed with the Unified Parkinson's Disease Rating Scale motor part III (34.41 [13.49] versus 28.38 [11.21]; p = 0.01) compared to non-carriers. There were statistically significant interactions between the two genetic factors, so that patients who carried both a mild GBA mutation and the APOE ɛ4 allele (n = 9) had more severe cognitive (p = 0.048) and motor dysfunction (p = 0.037).Conclusion: We found a high frequency of both GBA mutations and the APOE ɛ4 allele among AJ patients with DLB, both of which have distinct effects on the clinical disease phenotype, separately and in combination. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to examine awareness of decline in memory and in language in individuals with Alzheimer's disease (AD), by comparing participant and informant ratings, as well as these ratings and actual test performance.Methods: We analyzed data from 149 individuals with AD enrolled in the Alzheimer's Disease Neuroimaging Initiative (ADNI) who filled the Everyday Cognition questionnaire and performed memory and language tasks.Results: Participants provided significantly lower assessments of decline than did informants for both memory and language. There was a negative association between informant ratings and memory test scores but no association between participant ratings and memory test scores. Both participant and informant ratings correlated negatively with performance on the language tests. Informant, but not participant, ratings contributed to the prediction of one memory variable beyond demographic factors. Participant ratings contributed to the prediction of language scores beyond demographic factors more than did informant ratings.Conclusions: The findings reflect better awareness of decline in language than of decline in memory in individuals with AD. [ABSTRACT FROM AUTHOR]

Background:Studies of connected speech of individuals with Alzheimer’s disease (AD) report significant impairments relative to the language of cognitively intact participants. Considerably less research has focused on the association between dementia severity and language features. Aims:The current study examines how scores on a dementia screening test (the Mini-Mental Status Examination, MMSE) correlate with features of connected speech. Methods & Procedures:Thirty-five individuals with AD (range of MMSE scores = 3–25) and 35 cognitively intact participants provided picture descriptions. Ten language features were derived from their descriptions using an automated text analysis tool: total word number, percentage of content words, pronoun ratio, type-token ratio, mean word frequency, percentage of verbs, percentage of verbs in the most common morphological form in Hebrew, percentage of verbs in present tense, percentage of prepositions, and percentage of subordination markers. Information content was also analysed. Outcomes & Results:Group differences emerged in five language features as well as in information content, attesting for substantial lexical impairment in AD. Within the AD group, MMSE scores were correlated with type-token ratio, with mean word frequency, and with the number of information units. No equivalent correlations were found within the control group. Conclusions: Dementia severity associates with decreasing lexical diversity, increasing word frequency, and a reduction in relevant information content, but not with changes in grammatical features of language. A simple automated analysis of connected speech could be used clinically to define and track the decline in language abilities in AD. [ABSTRACT FROM PUBLISHER]

Objective: This study examines which cognitive measure best accounts for perseverations in individuals with memory impairment. Method: The sample included 85 individuals, of whom 21 had subjective memory concerns, 27 had mild cognitive impairment, and 37 had Alzheimer's disease. Participants produced responses on a semantic category fluency task and on the ideational fluency (IF) task from the Cambridge Cognitive Examination-Revised. Measures of word finding, working memory, and abstract thinking were also assessed. Results: Significant group differences in percentage of perseverations emerged on both tasks. No cognitive measure accounted for the percentage of perseverations on the semantic fluency task. A measure of abstract thinking was the best predictor of the percentage of perseverations on the IF task, followed by a measure of working memory. Conclusions: The underlying cognitive mechanisms that lead to perseverations differ across tasks, with perseverations on the IF task reflecting both conceptual deficits and working memory limitations. [ABSTRACT FROM AUTHOR]

What can tests of single-word production tell us about word retrieval in connected speech? We examined this question in 20 people with Alzheimer’s disease (AD) and in 20 cognitively intact individuals. All participants completed tasks of picture naming and semantic fluency and provided connected speech through picture descriptions. Picture descriptions were analyzed for total word output, percentages of content words, percentages of nouns, and percentages of pronouns out of all words, type–token ratio of all words and type–token ratio of nouns alone, mean frequency of all words and mean frequency of nouns alone, and mean word length. Individuals with AD performed worse than did cognitively intact individuals on the picture naming and semantic fluency tasks. They also produced a lower proportion of content words overall, a lower proportion of nouns, and a higher proportion of pronouns, as well as more frequent and shorter words on picture descriptions. Group differences in total word output and type–token ratios did not reach significance. Correlations between scores on tasks of single-word retrieval and measures of retrieval in picture descriptions emerged in the AD group but not in the control group. Scores on a picture naming task were associated with difficulties in word retrieval in connected speech in AD, while scores on a task of semantic verbal fluency were less useful in predicting measures of retrieval in context in this population. [ABSTRACT FROM PUBLISHER]

Background:The aim of this study was to examine the efficiency of the mini-Kingston standardized cognitive assessment-revised (mini-KSCAr) in classifying patients according to DSM-5 major and mild neurocognitive disorders (NCD) due to possible Alzheimer's disease (AD).Methods:Files of 85 individuals who were tested on the Kingston standardized cognitive assessment-revised were reviewed and scores were calculated for the mini-KSCAr. Medical history, psychiatric and physical status, basic and instrumental activities of daily living, as well as scores on the Cambridge cognitive examination-revised (CAMCOG-R), and the clinical dementia rating (CDR) scale were used to establish DSM-5 diagnoses of major or mild neurocognitive disorders (NCD) due to possible AD or no cognitive decline. All participants were tested on the Mini-Mental State Examination (MMSE) and the clock drawing test (CDT), and a subset (N = 28) were also tested on three well-known memory tasks.Results:Scores on the MMSE, CDT, and mini-KSCAr differed across groups, but only the mini-KSCAr significantly distinguished each group from the other two. The mini-KSCAr showed better sensitivity, specificity, and likelihood ratios (LRs) than did the MMSE and the CDT. A regression analysis revealed that the mini-KSCAr accounted for almost half of the variance in memory performance, whereas the MMSE and the CDT contributed nothing to this prediction once the mini-KSCAr was used.Conclusions:The mini-KSCAr is an efficient instrument for the diagnosis of DSM-5 major and mild NCD due to possible AD in a specialized psychogeriatric setting, and its utility is greater than that of the MMSE and the CDT. [ABSTRACT FROM AUTHOR]

Individuals with semantic dementia (SD) show progressive worsening of lexical-conceptual single word knowledge alongside preservation of nonsemantic aspects of language. The current study exam-ines morphological processing in SD. S.H.S., a Hebrew-speaking person with SD, completed eight tasks that tested inflection, linear derivation, and nonlinear derivation at three time points over six and a half years. S.H.S. correctly produced plural nouns and judged the grammaticality of noun-verb and noun-adjective inflectional agreement. A steeper decline was seen in the ability to judge irre-gularly versus regularly inflected forms. S.H.S. judged nationality suffixes accurately and produced diminutive and agentive suffixes successfully. He also relied on morphological decomposition when performing lexical decision. Judgement of sentences consisting of derived verbal participles was intact with regard to morphological considerations alone, but impaired when semantic considerations determined grammaticality. S.H.S.'s performance suggests that structural aspects of word knowledge might be functional in the face of a severe semantic impairment. [ABSTRACT FROM AUTHOR]

Abstract: Language production was examined in a woman with semantic dementia (SD) over a three-year time period. Narratives were analyzed for their propositional content, syntactic structure, morphological complexity, and lexical makeup. An additional analysis looked at the proportion of vague terms and pronouns out of all nominal expressions. Investigation of verb frequency, light/heavy verbs, verb type/token ratio, and verb argument structure was also conducted. Findings suggest that alongside a severe deterioration of the general message level and continual degradation of lexical retrieval mechanisms, syntactic and morphological aspects of connected speech remain essentially unaffected by SD. It is argued that SD leads to a dissociation between impaired conceptual knowledge and intact structure in language production. [Copyright &y& Elsevier]

Sentence comprehension abilities were investigated in a patient with semantic dementia who was administered tests of semantic knowledge and sentence comprehension over a 5-year period. Results showed that despite a severe and continual degradation in semantic knowledge, syntactic comprehension abilities remained largely intact. Evidence was also found for a codependency between semantics and syntax in a task in which knowledge about conceptual number influenced subject-verb agreement in the patient and in control participants. Results are discussed in relation to the nature of the sentence comprehension impairment in semantic dementia and with reference to the modularity of the components of the language processing system. [ABSTRACT FROM AUTHOR]