EXPRESS: Effects of Acute Exercise Intensity on Source Episodic Memory and Metamemory Accuracy

Prior research suggests that behavioral (e.g., exercise) and psychological factors (e.g., metamemory; monitoring and control of one’s memory processes) may influence memory function. However, there is conflicting results on the optimal intensity of acute exercise to enhance memory and whether acute exercise can also enhance metamemory. Further, very limited research has evaluated whether acute exercise can influence source episodic memory. The objective of this study was to evaluate whether there is an intensity-specific effect of acute aerobic exercise on source episodic memory and metamemory accuracy. Thirty young adults participated in a three condition (Control/Moderate/Vigorous-Intensity Exercise), within-subject counterbalanced experimental study. After each intervention, participants completed source episodic memory and metamemory tasks. Results demonstrated that acute exercise, relative to control, was effective in enhancing source episodic memory, but not metamemory accuracy. Vigorous-intensity acute exercise was the most optimal intensity to enhance source episodic memory. Overall, our findings suggest that there is an intensity-specific effect of acute exercise on source episodic memory. Further, when exercise-related improvements in memory occur, young adults may be unaware of these memory benefits from exercise.

Metamemory monitoring in Alzheimer’s disease A systematic review

ABSTRACT Metamemory is the awareness of one’s own knowledge and control of memory, and refers to the online ability to gather information about the current state of the memory system. Objective: Metamemory is one’s own knowledge and control of memory. A systematic review was performed to identify the types of tasks used for evaluating metamemory monitoring, the stimuli used in these tasks, their limitations and the outcomes in people with Alzheimer’s disease (PwAD). Methods: This systematic review followed PRISMA methodology. A search of Pubmed, Scopus and Web of Science electronic databases was carried out in September, 2018, identifying experimental investigations of metamemory and dementia. Results: We included 21 studies. The most common tasks used were judgement of learning, feeling of knowing, judgement of confidence and global prediction. The rates of discrepancy between PwAD and caregivers still need further research. The Rey Auditory Verbal Learning Test was the most used list of words. PwAD are able to accurately rate their memory functioning and performance, when the evaluation is done soon afterwards. PwAD tend to overestimate their functioning and performance when the judgement involves forward-looking vision. Conclusion: In the context of metamemory impairment, clinicians and caregivers should seek interventions aiming to identify compensatory styles of functioning. This systematic review provides initial evidence for the use of metamemory measures as part of broader assessments evaluating Alzheimer’s disease.

Changes in ventromedial prefrontal and insular cortex support the development of metamemory from childhood into adolescence

Metamemory monitoring, or the ability to introspect on the accuracy of one’s memories, improves considerably during childhood, but the underlying neural changes and implications for intellectual development are largely unknown. The present study examined whether cortical changes in key brain areas hypothesized to support metacognition contribute to the development of metamemory monitoring from late childhood into early adolescence. Metamemory monitoring was assessed among 7- to 12-y-old children (n = 145) and adults (n = 31). Children returned for up to two additional assessments at 8 to 14 y of age (n = 120) and at 9 to 15 y of age (n = 107) (n = 347 longitudinal scans). Results showed that metamemory monitoring continues to improve from childhood into adolescence. More pronounced cortical thinning in the anterior insula and a greater increase in the thickness of the ventromedial prefrontal cortex over the three assessment points predicted these improvements. Thus, performance benefits are linked to the unique patterns of regional cortical change during development. Metamemory monitoring at the first time point predicted intelligence at the third time point and vice versa, suggesting parallel development of these abilities and their reciprocal influence. Together, these results provide insights into the neuroanatomical correlates supporting the development of the capacity to self-reflect, and highlight the role of this capacity for general intellectual development.