The Short-Term Effects of Activity Engagement on Working Memory Performance in Older Age

Does a single bout of activity engagement have short-term effects on cognition in daily life? Using a smartphone-based ambulatory assessment design, this study examined the duration of the effects of three types of activities (i.e., sociocognitive, passive leisure, and physical activities) on working memory performance. For seven times per day (i.e., approximately every 2 hr) over 15 days, 150 healthy older adults (aged 65-91 years) in Switzerland reported their present activities and completed working memory assessments. In an examination of within-person concurrent associations, results from a multilevel model showed that passive leisure activities were negatively associated with working memory. Extending this to time-lagged dynamics, results from multilevel vector autoregression models showed that the negative effect of passive leisure activities and a positive effect of sociocognitive activities on working memory performance appeared 6 hr later and faded out completely by 8 hr later. Follow-up analyses showed that the time-lagged effects of activity engagement were evident among relatively younger individuals with lower levels of formal education. In sum, our findings suggest that a single bout of activity engagement has an impact on cognitive performance as quickly as 6 hr. In line with the "use it or lose it" hypothesis, our findings highlight the importance of continuous and active engagement in sociocognitive activities in older age. Public Significance Statement A single bout of activity engagement was shown to have an impact on cognitive performance as quickly as 6 hr later and faded out by 8 hr. It is important to continuously engage in sociocognitive activities in older age. Understanding "how to" engage in everyday activities in relation to cognitive performance could help older adults manage their daily activities strategically and, possibly, wisely.