Repetition Priming in Individuals with Amnestic Mild Cognitive Impairment and Alzheimer's Dementia: a Systematic Review and Meta-Analysis

Monitoring reaction time to digital device in the very-old to detect early cognitive decline

Early detection of cognitive decline is essential for timely intervention and effective management of age-related impairments. We monitored repetitive reaction times to a simple task on senior-friendly tablet computers among 72 functionally independent older adults, with a mean age of 82, ranging up to 100 years, within natural settings over two years. Functional principal component analyses revealed a consistent decrease in reaction time in line with their task experience among those without subjective cognitive decline. Conversely, individuals reporting subjective cognitive decline showed no consistent trend and exhibited wide variability over time. These distinctive reaction time trajectories in very old adults suggest the potential for monitoring as a non-invasive, convenient method for early detection of cognitive impairment.

The diagnostic value of cognitive assessment indicators for mild cognitive impairment (MCI)

OBJECTIVE

This study aims to evaluate and analyze the standard diagnostic methods for mild cognitive impairment (MCI).

METHODS

This study used a prospective case-control study to examine baseline data and diagnostic indicators in a population of elderly with MCI. Based on different cognitive abilities, this study divided MCI and healthy control groups. The diagnostic indicators included CDT, MOCA, MMSE, PSQI, MBI, DST, HAMD, AD-related blood markers, and olfactory testing. The diagnostic value of each indicator was done using the ROC curve.

RESULTS

This study included 240 adult participants, 135 in the health group and 105 in the MCI group. A comparison of baseline data revealed statistically significant differences between the two groups regarding age, blood glucose, MMSE, CTD, MOCA, ability to perform daily living, AD-related blood indices and olfactory tests (all p < 0.05). Logistic regression analysis statistically showed that age, MOCA, and CDT were independent diagnostic factors for MCI (all p < 0.05). Combining these three indicators has the best diagnostic specificity (92.54%). AD-related blood and olfactory tests indices had only moderate diagnostic values (AUC: 0.7-0.8).

CONCLUSION

Age, MOCA, and CDT are good indicators for diagnosing early-stage MCI. AD-related blood indices and olfactory tests can serve as valuable adjuncts in diagnosing MCI.

Exploring why "memory loss" is a misleading descriptor of people living with dementia and can lead to dysfunctional care

Amidst goals for prevention and improved treatment for people living with dementia, much remains needed to enhance the quality of life of those currently diagnosed, especially the transfer of accurate information from professionals to the public. Although many healthcare professionals understand the various types of memory and which are likely to be more affected than others during the progression of dementia, lay persons are more frequently unaware of that important information. The terms used to describe the symptoms of dementia can have a great impact on perceptions of faculties that are absent, compromised, or preserved. Understanding the nuances of preserved memory faculties and other cognitive abilities retained by persons with dementia is important in this regard. The term "memory loss" as a descriptor of the syndrome of dementia and ascribing it to persons with dementia connotes an inability to form new memories and participate in meaningful social interactions, which is detrimental to their personhood. From a multidisciplinary approach drawn from neurology, neurobiology, psychology, and case vignettes, we aim herein to highlight the ways in which the term "memory loss" can be inaccurate, counterproductive and potentially promote dementia-related misperceptions, malignant positioning and malignant social psychology. Persons with dementia unequivocally struggle with explicit memory, or recalling on demand, but retain implicit memory, as evidenced by research and everyday actions. Therefore, we propose the use of alternative medical language to reflect accurately memory impairment and preservation of some important memory capabilities.

Set Size of Information in Long-Term Memory Similarly Modulates Retrieval Dynamics in Young and Older Adults

Our ability to rapidly distinguish new from already stored (old) information is important for behavior and decision making, but the underlying processes remain unclear. Here, we tested the hypothesis that contextual cues lead to a preselection of information and, therefore, faster recognition. Specifically, on the basis of previous modeling work, we hypothesized that recognition time depends on the amount of relevant content stored in long-term memory, i.e., set size, and we explored possible age-related changes of this relationship in older humans. In our paradigm, subjects learned by heart four different word lists (24, 48, 72, and 96 words) written in different colors (green, red, orange, and blue). On the day of testing, a color cue (e.g., green) indicated with a probability of 50% that a subsequent word might be from the corresponding list or from a list of new words. The old/new status of the word had to be distinguished via button press. As a main finding, we can show in a sample of n = 49 subjects, including 26 younger and 23 older humans, that response times increased linearly and logarithmically as a function of set size in both age groups. Conversely, corrected hit rates decreased as a function of set size with no statistically significant differences between both age groups. As such, our findings provide empirical evidence that contextual information can lead to a preselection of relevant information stored in long-term memory to promote efficient recognition, possibly by cyclical top-down and bottom-up processing.