Toward an Understanding of Healthy Cognitive Aging: The Importance of Lifestyle in Cognitive Reserve and the Scaffolding Theory of Aging and Cognition

Abstract

The World Health Organization (WHO) aims to improve our understanding of the factors that promote healthy cognitive ageing and combat dementia. Ageing theories that consider individual ageing trajectories are of paramount importance to meet the WHO’s aim. Both the revised Scaffolding Theory of Aging and Cognition (STAC-r) and Cognitive Reserve theory (CR) offer theoretical frameworks for the mechanisms of cognitive ageing and the positive influence of an engaged lifestyle. STAC-r additionally considers adverse factors, such as depression. The two theories explain different, though partly overlapping aspects of cognitive ageing. Currently, it is unclear where the theories agree and differ and what compensation mechanism of age-related cognitive decline might be better explained by either STAC-r, CR, or by both. This review provides an essential discussion of the similarities and differences between these prominent cognitive ageing theories, their implications for intervention methods and neurodegenerative disease, and significant shortcomings that have not yet been addressed. This review will direct researchers to common insights in the field and to intervention targets and testable hypotheses for future research. Future research should investigate the potential use of STAC-r in neurodegenerative diseases and provide clarity as to what combination of factors build CR, including their relative importance and when in life they are most effective.

Getting the brain into gear: An online study investigating cognitive reserve and word-finding abilities in healthy ageing

“…Hence, CR might not mitigate word-finding difficulties in older age. Alternatively, CR might increase performance when task demands are high by enhancing general cognitive processes (for a discussion, see [ 80 ]). Hence, the effects from CR might become too subtle to detect whilst the beneficial effects on word finding from other cognitive processes becomes apparent.…”

“…Hence, CR in itself is a multidimensional construct and this multidimensionality might be reflected through the low Cronbach’s Alpha score. However, there is currently no consensus as to what lifestyle choices and lifetime experiences must be included to compute an individual’s CR level (for a discussion, please see [ 80 ]). To better capture CR, the current study included a range of CR proxies, including years of education, frequency of cognitively stimulating activities, and physical activities.…”

“…If changes in CR negatively affects cognitive functioning, timely interventions are necessary to counteract the negative consequences and increased risk of dementia by, for example, increasing late-life CR. Such interventions can include cognitive training, education later in life, and promoting healthy lifestyle choices throughout the lifespan (for a discussion on interventions, please see [ 80 ]).…”

The Canadian platform for research online to investigate health, quality of life, cognition, behaviour, function, and caregiving in aging (CAN-PROTECT): study protocol, platform description, and preliminary analyses

“…[23] Building on cognitive reserve, the scaffolding theory of aging is a multi-faceted multi-dimensional model that includes activities that build reserve, as well as those that reduce neuroplasticity. [24] In essence, this model incorporates risk and resilience, both of which are important factors to address.…”

A bidirectional relationship between cognitive reserve and cognition among older adults in a rural Chinese community: a cross-lagged design

“…Stern and colleagues ( Stern et al, 2020 ) have argued that CR is a model of positive reserve that can change with lifestyle choices and events across the lifespan, improving the efficiency or flexibility of cognitive processes to cope with cognitive decline. Yet, it is not clear whether CR can accumulate across the lifespan, and future research should consider not only healthy lifestyle factors, but also the negative effects of cognitive aging ( Oosterhuis et al, 2023 ). Previous research has focused on the unidirectional relationship, where CR proxies are considered to enhance cognitive reserve, which in turn supports better cognitive function ( Stern, 2012 ; Mondini et al, 2016 ).…”