The Association between the Binding Processes of Working Memory and Vascular Risk Profile in Adults

The Mixed Role of Sleep and Time of Day in Working Memory Performance of Older Adults with Mild Cognitive Impairment

The importance of night sleep for maintaining good physical and cognitive health is well documented as well as its negative changes during aging. Since Mild Cognitive Impairment (MCI) patients bear additional disturbances in their sleep, this study aimed at examining whether there are potential mixed effects of sleep and afternoon time of day (ToD) on the storage, processing, and updating components of working memory (WM) capacity in older adults with MCI. In particular, the study compared patients' performance in the three working memory components, in two-time conditions: "early in the morning and after night sleep", and "in the afternoon and after many hours since night sleep". The Working Memory Capacity & Updating Task from the R4Alz battery was administered twice to 50 older adults diagnosed with MCI. The repeated measures analysis showed statistically significant higher performance in the morning condition for the working memory updating component (p < 0.001). Based on the findings, it seems that the afternoon ToD condition negatively affects tasks with high cognitive demands such as the WM updating task in MCI patients. These findings could determine the optimal timing for cognitive rehabilitation programs for MCI patients and the necessary sleep duration when they are engaged in cognitively demanding daily activities.

Trajectories of Cognitive Impairment in Adults Bearing Vascular Risk Factors, with or without Diagnosis of Mild Cognitive Impairment: Findings from a Longitudinal Study Assessing Executive Functions, Memory, and Social Cognition

With the aging of the population, a key concern of both societies and health services is to keep the population cognitively healthy until the maximum age limit. It is a well-known fact that vascular aging has a negative effect on the cognitive skills of adults, putting them at greater risk of developing dementia. The present longitudinal study aimed to evaluate the main dimensions of cognition in two pathological groups with different health profiles: a group of adults with vascular risk factors (VRF) (n = 35) and a group of adults with vascular risk factors and mild cognitive impairment (VRF + MCI) (n = 35). The two groups were matched in age, education, and gender. They were assessed with extensive neuropsychological testing at three different times with a distance of about 8 months between them; the assessment regarded executive functions, memory capacity, and Theory of Mind abilities. The analyses carried out were (a) mixed-measures ANOVA, (b) repeated measures ANOVA, and (c) ANOVA. The findings showed that global cognitive status and short-term memory are the main cognitive abilities that decline in community dwelling people bearing VRF. Hence, this group of adults should be examined at least every 2 years for this decline. As regards people with both VRF and MCI, it seems that the assessment of Theory of Mind abilities can better capture their further impairment. Global cognitive status, task/rule switching function, and long-term memory (delayed verbal recall) were revealed as the abilities that clearly and steadily differentiate VRF people with and without MCI.

Aging and feature binding in visual working memory

Older adults have reduced performance in visual working memory tasks in comparison to young adults, but the precipitators of the age-related impairment are not fully understood. The most common interpretation of this difference is that older adults are incapable of maintaining the same amount of object representations as young adults over short intervals (in line with the fixed-slot model of working memory). However, it has remained largely unexplored whether the age-related decline is only due to the number of representations that older individuals can retain in visual working memory, or whether the content of the representation(s) may have an effect as well (in line with the flexible-resource model of working memory). Feature binding studies represent an interesting research line to examine the content of older adults' representations. In this mini-review, we present the main results across feature binding studies in aging, as well as highlight the importance of manipulating both the representation content and number to have a stress test of the various models of working memory and their contribution to aging. Overall, feature binding studies, together with the simultaneous manipulation of set size, will allow us to better understand the nature of the age-related decline of visual working memory.