How does age affect the link between activity and cognition?

A publication by researchers at SFU and UBC explores the relationship between physical activity and cognitive decline in middle and older-aged adults using data from the Canadian Longitudinal Study on Aging (CLSA).

Spearheaded by John Best (SFU) and Ryan Falck (UBC) along with Theodore Cosco (SFU) and Andrew Wister (SFU), the publication “Age differences in the moderating effects of neighbourhood disadvantage on the relationship between physical activity and cognitive function: A longitudinal analysis of the Canadian Longitudinal Study on Aging,” analyzed this link. 

Changes in cognitive function as people age

As adults age, they may experience changes in cognitive function, such as declines in memory and executive function. Research has been conducted to study the associations between physical activity and cognitive maintenance; however, research on the relationship between physical activity and environmental factors on cognition is limited (Erickson et al., 2022).  

Previous research has shown that people with higher household incomes and levels of education are more physically active than those with lower incomes and education (Talaei et al., 2013). In western high-income countries, marginalized populations are more physically active, but have poorer health compared with non-marginalized groups (Findlay, 2011). It is also important to note that the risk of cognitive decline is more than two-fold greater for people with low socio-economic status (Koster et al., 2005), and more than two-thirds of dementia cases are from lower and middle-income countries (Prince et al., 2015). 

The role of environmental factors

In this study, neighbourhood disadvantages refer to 1) social deprivation in relationships and 2) material deprivation in wealth (Townsend, 1987). Neighbourhood material disadvantage is associated with poorer cognition among older adults. However, it is unclear whether neighbourhood social disadvantages are associated with cognition or physical activity (Fisher et al., 2004; Li et al., 2005). 

Considering how disparities in individual and environmental socio-economic factors like neighbourhood disadvantages affect cognitive functioning as people age, can provide insight about how a person’s environment impacts their physical activity levels and cognitive performance. 

During this study, they were interested in two aspects of cognitive decline, 1) the decline in memory performance and 2) the decline in top-down control and planning abilities. The results indicated that the benefits of physical activity in mitigating cognitive decline are age and neighbourhood dependent. For middle-aged adults, the benefits of physical activity are stronger among those who live in more disadvantaged neighbourhoods compared to those living in less disadvantaged neighbourhoods. For older adults, physical activity is associated with less cognitive decline regardless of the degree of neighbourhood material disadvantage.

Findings from the study

These findings reveal that disadvantaged neighbourhoods have certain characteristics (higher levels of pollution, lower safety, limited opportunities for social and cognitive enrichment) that may be detrimental to cognitive health. This suggests that physical activity may help counteract negative environmental effects on cognitive health, especially among middle-aged adults.