This cross-sectional research aims to improve understanding of the brain structures involved in working memory in older adults (aged 51-80). Using baseline MRI and cognitive data from the UK Biobank, we will use the volumes of various brain structures implicated in working memory (e.g., the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex, parietal cortex, hippocampus, temporal cortex, cerebellum, basal ganglia, cingulate cortex, thalamus, and insula), to explore their influence on working memory performance as measured by the UK Biobank Numeric Memory Test. Working memory is an executive function that is necessary for many higher-order cognitive tasks in daily life, including learning, comprehension, reasoning, and language, but despite its clinical relevance, the neuroanatomical correlates of working memory have rarely been assessed using large population-based samples. Further, previous studies have often failed to account for the potentially confounding effects of age, sex, education level, and total intracranial volume (i.e., head size) on the relationship between brain volumes and cognitive performance. Therefore, we aim to use multi-level mixed effects linear regression modelling to examine whether these brain regional volumes can predict working memory performance in older adults, while accounting for the influence of age, sex, education, and intracranial volume. We also aim to generate age-stratified normative data for the UK Biobank Numeric Memory Test (adjusted for sex and education level).
