Memory aging and brain maintenance

Abstract

Episodic memory and working memory decline with advancing age. Nevertheless, large-scale population-based studies document well-preserved memory functioning in some older individuals. The influential ‘reserve’ notion holds that individual differences in brain characteristics or in the manner people process tasks allow some individuals to cope better than others with brain pathology and hence show preserved memory performance. Here, we discuss a complementary concept, that of brain maintenance (or relative lack of brain pathology), and argue that it constitutes the primary determinant of successful memory aging. We discuss evidence for brain maintenance at different levels: cellular, neurochemical, gray- and white-matter integrity, and systems-level activation patterns. Various genetic and lifestyle factors support brain maintenance in aging and interventions may be designed to promote maintenance of brain structure and function in late life.

Working memory in middle-aged males: Age-related brain activation changes and cognitive fatigue effects

“…This comparison minimized many of the drawbacks of using a cross-sectional design to investigate age-related changes in brain activation (as, for example, significant differences in WM task performance between the two age groups were not evident). However, it should be noted that while cross-sectional analyses have shown over-recruitment of frontal areas with increasing age, longitudinal analyses have shown under-recruitment of frontal areas with age (attributing cross-sectional findings to the effects of a small group of high performing older adults, who when followed longitudinally, also demonstrated reduced recruitment with age) (Nyberg, Loveden, Riklund, Lindenberger, & Backman, 2012). As such, although our high performing middle-aged adults show relative over-recruitment compared to the younger group, they may show reductions in brain activation with age when followed longitudinally.…”

A right hemisphere role in cognitive reserve

“…A closely related and complementary concept is that of 'brain maintenance', proposed by Nyberg and Colleagues (Nyberg, et al, 2012). Older adults vary in the degree of age-related cellular damage to basic brain structures, according to this theory and these differences are reflected in an age-related increase in variability in cognitive function.…”

CA3 size predicts the precision of memory recall

“…Nevertheless, we are generally able to recall many of these past experiences as distinct episodes, although we are not all equally adept at doing so. There is substantial individual variation in retrieval ability and the precision with which we can differentiate past events (1,2). This is most acute as we age and in conditions such as dementia, where confusion about the past is often evident (2).…”

“…There is substantial individual variation in retrieval ability and the precision with which we can differentiate past events (1,2). This is most acute as we age and in conditions such as dementia, where confusion about the past is often evident (2). There is keen interest, therefore, in elucidating the neural mechanisms that allow us to recollect numerous life experiences despite a high degree of intermemory similarity.…”