Healthy older adults show variation in cognitive performance not directly related to neuropathological measures. Iron-mediated oxidative stress may cause the neuronal vulnerability underpinning healthy ageing. MRI Quantitative Susceptibility Mapping [QSM] measures tissue composition and is dominated by iron content in the brain. This project will use QSM to measure brain iron changes in healthy adults and investigate the relationship between these and cognitive performance at two different field strengths. Scanning at 7 Tesla may reveal layer-specific information not available using conventional 3-Tesla acquisitions. This will provide important insights into the neural substrates of early cognitive changes in healthy ageing.
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