Abstract
In recent decades, the burden associated with cognitive decline and other neuropsychological changes in healthy ageing has increased significantly due to the rapid increase in population ageing. This has heightened the need to better understand brain ageing and develop interventions to optimise neuropsychological functioning in older adults. Additionally, more recently, a global COVID-19 pandemic has led to the need for people to wear face masks in public. It should be noted that older populations are at particular risk of more severe disease, and thus are in greater need of wearing protective face masks, yet in theory older adults could be more adversely affected given natural declines that occur with advancing age (e.g., cognitive and cerebrovascular). This thesis reports on four studies that addressed these issues. The first study, which was a systematic meta-analytic review investigated age differences in emotional information processing. The results revealed some evidence of an overall age-related positivity effect consistent with a shift toward positivity with adult ageing. However, consideration of emotionally neutral stimuli revealed significant age differences in emotional processing for negative stimuli only, with younger adults showing a stronger negativity bias, and a distinct pattern emerged for face stimuli, which may reflect the biological and social significance of facial expressions. The second study, which investigated the effect of an interval stair climbing intervention on cognition and mood in older adults indicated improved cognition following the moderate-to-high intensity stair climbing intervention; however, rather than improving mood, older adults reported feeling more tired. These outcomes provide initial indications that this mode of exercise that can easily be translated to naturalistic settings offers promise as an intervention strategy, but more research is needed to optimise the protocol to suit aged populations. The third study addressed the effect of wearing face masks for at least 8 hours on neuropsychological functioning in younger adults and the results showed that participants reported feeling less happy and more tense during the mask compared to the no-mask control session. Additionally, the results revealed a small but significant adverse effect of wearing a surgical face mask on the more challenging condition of a selective attention task. This evidence of adverse effects in a university population signalled that future research is needed to investigate the effects of wearing surgical face masks in vulnerable populations (e.g., people with asthma and older adults). Finally, the fourth study which addressed the effect of wearing face masks for a full day on brain functioning in older adults showed a significant difference in one instance for just one of the hemodynamic responses and significant reductions in feelings of calm; however, the overall effect of wearing a face mask on brain functioning should be considered negligible as there were no other significant mask-induced effects which is encouraging but somewhat surprising given the effects in younger adults. A follow-up trial with a larger sample size will be needed before any firm conclusion can be drawn.