Theories of adult brain development suggest differential rates of age-related change in function across cortical and subcortical sub regions. However, it remains unclear if these trends extend to the aging dopamine system. Using PET imaging, my colleagues and I have recently explored adult age differences in dopamine D2/3 receptor binding potential across several cortical and subcortical brain regions – you can also explore the data using this web application I developed.  We found that the rate and pattern of decline in dopamine receptor availability was regionally heterogeneous and did not fit with existing theories of adult brain development (Seaman, et al., in press). This variation suggests that existing theories of adult brain development may need to be modified to better account for dopaminergic system aging. There was also somewhat surprising evidence for preservation of function with age in a subset of ventromedial brain regions, which may explain one paradox of aging: some dopamine-mediate cognitive functions are preserved with age while other show marked decline.