Paying attention: cost of cumulative life stress is for older adults only

Experimental evidence consistently demonstrates older adults often perform worse than younger adults across various cognitive domains. Prior studies reported that older adults with high lifetime stress perform worse on working memory and inhibitory tasks than both younger individuals and older adults with low stress. Notably, low-stress older adults performas well as younger adults, indicating that life-time cumulative stress, rather than age alone, may drive some cognitive decline during aging. However, this stress-age affect on attention, the underlying process of both working memory and inhibition is yet to be investigated. In this within-subjects cross-sectional online study 141 participants (n = 85 under 30 and n = 56 over 60) identified two target words in an Attentional Blink task. Participants also reported their lifetime and perceived stress and their state anxiety. Using linear mixed models and Bayes Factors, we provide evidence that age and lifetime stress predict overall attentional performance on the Attentional Blink task. This supports the hypothesis that older high life-time stress participants would score lower on the attentional task compared to older low-stress participants and younger participants. Due to the interconnected nature of attention, these results suggest the stress-age interaction could be a factor in other cognitive domains that are susceptible to age-related decline. On a positive note, the results also suggest that attentional decline during aging, like impairments in working memory and inhibition, may be exacerbated by factors outside of simply getting older (here, elevated lifetime exposure to stress) and may therefore, not be inevitable.