Verbal fluency tests assess global cognitive status but have limited diagnostic differentiation: evidence from a large-scale examination of six neurodegenerative diseases

Association between possible sarcopenia and domain-specific cognitive impairment in middle-aged and older adults: Insights from the Gan-Dau Healthy Longevity Plan

BACKGROUND

Given the established association between sarcopenia and cognitive impairment was mainly in the older and oldest-old population or people with relatively limited education, this study extends the investigation to community-dwelling middle-to-old age adults in urban communities, emphasizing the need for preventive intervention for muscle health and healthy longevity.

METHODS

Data of 712 participants from the Gan-Dau Healthy Longevity Plan were retrieved for analysis, and all participants were stratified by age (50-64, 65-74 and 75+ years old). Possible sarcopenia was defined by 2019 consensus report of the Asian Working Group for Sarcopenia (AWGS). This study used four neuropsychological tests for analysis, i.e., Mini-Mental Status Examination (MMSE), California Verbal Learning Test II (CVLT-SF), Digital Symbol Substitution Test (DSST) and Verbal fluency (VF) for global and domain-specific cognitive function. Multivariate generalized linear models (GLMs) were employed to investigate the associations between possible sarcopenia and cognitive function in each age-specific groups.

RESULTS

The prevalence of possible sarcopenia increased with age, with 31.8 %, 37.7 %, and 55.6 % in participants aged 5064, 65-74 and, 75+ years, respectively. On the other hand, cognitive performance declined with age. In particular, among participants aged 75+ years with possible sarcopenia, their cognitive performance were poorer than robust counterparts, including MMSE (26.6 [3.4] vs. 27.4 [2.6]), CVTL-SF (total score: 21.5 [5.4] vs. 23.8 [5.5]; 30-second delayed recall: 6.0 [1.7] vs. 6.5 [1.6]), DSST (32.8 [14.3] vs. 41.3 [18.7]), and VF (12.8 [5.1] vs. 14.8 [4.9]). Multivariate generalized linear model indicated that possible sarcopenia was associated with lower MMSE (β: -0.70, p = 0.014) and lower DSST (β: -7.00, p = 0.010) in those aged 50-64 years. Moreover, possible sarcopenia was associated with lower CVLT-SF (total score β:-1.90, p = 0.028), lower DSST (β: -6.45, p < 0.001), and lower VF (β: -1.64, p=0.026) in 75+ years group.

CONCLUSIONS

An association exists between possible sarcopenia and cognitive impairment, encompassing global cognition, delayed memory, verbal fluency, and executive function, among community-dwelling adults of mid-to-old age. Future research is warranted to explore the temporal alterations in this association and the potential effects of interventions aimed at fostering healthy longevity.

Applicability and usefulness of pupillometry in the study of lexical access. A scoping review of primary research

Pupil dilation has been associated with the effort required to perform various cognitive tasks. At the lexical level, some studies suggest that this neurophysiological measure would provide objective, real-time information during word processing and lexical access. However, due to the scarcity and incipient advancement of this line of research, its applicability, use, and sensitivity are not entirely clear. This scoping review aims to determine the applicability and usefulness of pupillometry in the study of lexical access by providing an up-to-date overview of research in this area. Following the PRISMA protocol, 16 articles were included in this review. The results show that pupillometry is a highly applicable, useful, and sensitive method for assessing lexical skills of word recognition, word retrieval, and semantic activation. Moreover, it easily fits into traditional research paradigms and methods in the field. Because it is a non-invasive, objective, and automated procedure, it can be applied to any population or age group. However, the emerging development of this specific area of research and the methodological diversity observed in the included studies do not yet allow for definitive conclusions in this area, which in turn does not allow for meta-analyses or fully conclusive statements about what the pupil response actually reflects when processing words. Standardized pupillary recording and analysis methods need to be defined to generate more accurate, replicable research designs with more reliable results to strengthen this line of research.

Multivariate word properties in fluency tasks reveal markers of Alzheimer's dementia

INTRODUCTION

Verbal fluency tasks are common in Alzheimer's disease (AD) assessments. Yet, standard valid response counts fail to reveal disease-specific semantic memory patterns. Here, we leveraged automated word-property analysis to capture neurocognitive markers of AD vis-à-vis behavioral variant frontotemporal dementia (bvFTD).

METHODS

Patients and healthy controls completed two fluency tasks. We counted valid responses and computed each word's frequency, granularity, neighborhood, length, familiarity, and imageability. These features were used for group-level discrimination, patient-level identification, and correlations with executive and neural (magnetic resonanance imaging [MRI], functional MRI [fMRI], electroencephalography [EEG]) patterns.

RESULTS

Valid responses revealed deficits in both disorders. Conversely, frequency, granularity, and neighborhood yielded robust group- and subject-level discrimination only in AD, also predicting executive outcomes. Disease-specific cortical thickness patterns were predicted by frequency in both disorders. Default-mode and salience network hypoconnectivity, and EEG beta hypoconnectivity, were predicted by frequency and granularity only in AD.

DISCUSSION

Word-property analysis of fluency can boost AD characterization and diagnosis.

HIGHLIGHTS

We report novel word-property analyses of verbal fluency in AD and bvFTD. Standard valid response counts captured deficits and brain patterns in both groups. Specific word properties (e.g., frequency, granularity) were altered only in AD. Such properties predicted cognitive and neural (MRI, fMRI, EEG) patterns in AD. Word-property analysis of fluency can boost AD characterization and diagnosis.

Bridging the Gap: Association between Objective and Subjective Outcomes of Communication Performance in People with Parkinson's Disease Evaluated for Deep Brain Stimulation

Background

Decrements in verbal fluency following deep brain stimulation (DBS) in people with Parkinson's disease (PwP) are common. As such, verbal fluency tasks are used in assessing DBS candidacy and target selection. However, the correspondence between testing performance and the patient's perception of communication abilities is not well-established.

Methods

The Communication Participation Item Bank (CPIB) was administered to 85 PwP during pre-DBS neuropsychological evaluations. Central tendencies for CPIB responses and correlations between CPIB total scores, clinical and demographic factors, and language-based tasks were examined.

Results

Most PwP indicated some degree of communication interference on the CPIB. Worse scores on semantic fluency and greater motor impairment were associated with more communication interference.

Conclusions

Our findings suggest an incomplete correspondence between commonly used language-based tests and patient-reported outcomes of communication abilities. The need for a functional communication instrument that reflects the different aspects of communication abilities in functional contexts is emphasized.