Grant: Doctoral Research Award: Canada Graduate Scholarships

Theone Paterson, Ph.D. University of Victoria. Life expectancy has risen significantly, with the proportion of the world's population over age 60 expected to nearly double by 2050. As our population ages, there is a pressing need to examine factors that impact cognitive aging. Despite research showing that stress exposure increases risk of dementia and mild cognitive impairment, currently available studies generally look at stress at a specific timeframe of exposure and so do not consider the impacts of cumulative (acute + chronic) stress across the lifespan. This study will examine how lifetime stress influences brain activity that drives our thinking ability, to better understand the effects of stress on older adults' cognition. Both acute and chronic stress affect the biological aging process, and importantly, cognitive abilities such as decision-making. The prefrontal cortex, a brain region associated with executive functions (e.g., decision-making), is particularly susceptible to the effects of stress. This can become more problematic as we age and require these skills to take care of ourselves, plan meals, and stay safe. Studies have also shown that sex (and gender) impacts aspects of brain activity, cognition, and aging. This study will, thus, also examine how sex/gender and lifetime stress each impact cognition in older adults. Participants will complete cognitive testing (assessing attention, etc.) while undergoing functional Near-Infrared Spectroscopy (fNIRS) brain imaging and will complete questionnaires on various lifetime stressors. Statistical analyses will examine how lifetime stress impacts neural activation and cognitive performance, as well as whether the influence of stress on cognition and brain activity is impacted by sex (and/or gender). Findings will lead to a better understanding of the different types of stressors that may most impact brain health and inspire future research into targeted strategies to support aging individuals.