The rise and fall of executive functions: Modelling the neural mechanisms of age-related changes in higher cognitive abilities. (360G-Wellcome-107392_Z_15_Z)

This research aims to determine how changes in prefrontal structure and function affect executive functions across the lifespan. This project attempts to address three challenges that pervade the literature on neurocognitive ageing: Small samples, cross-sectional data and predominantly univariate statistical approaches. This project hopes to overcome these limitations by access to, and close collaboration with, three unique developmental studies: NSPN in London, Cam-CAN in Cambridge and BASE-II at the MPI in Berlin. I will use psychometric models and longitudinal, multimodal neuroimaging to address four key questions. First, I will use Latent Growth Curve Modelling to determine optimal neurodevelopmental trajectories in adolescents. Second, I will use hierarchical MIMIC models to capture the cascade of effects of white matter changes on processing speed and reasoning. Third, I will examine task-based functional connectivity of the prefrontal cortex following prefrontal atrophy to provi de a critical test of the scaffolding hypothesis. Finally, I will use equality-constrained multifactor MIMIC models to determine and compare prefrontal structure and function between healthy and non-healthy cognitive agers. Together, the unique nature of the datasets and novelty of the statistical approaches promise to greatly increase our understanding of neurocognitive development and ageing.