Neuroimaging the impact of aging on economic decisions

Massachusetts Institute Of Technology, Cambridge MA

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Linked publications & trials

Abstract

[unreadable] DESCRIPTION (provided by applicant): This proposal aims to examine how healthy aging influences the psychological and neural bases of economic choice. Older individuals face important and often complex decisions about retirement, income distribution, insurance, and other financial and health-related matters. These decisions invariably have consequences that extend into the future, and usually involve some risk. There is clear evidence that healthy aging alters many of the psychological capacities and neural systems that are likely to be engaged by such economic decisions. This proposal develops an integrated approach to age-related changes in the neural mechanisms involved in both temporal and probabilistic discounting, providing an in-depth and integrated approach to this important domain. [unreadable] [unreadable] Temporal discounting refers to the observation that individuals experience diminishing value from anticipated money or goods as they become more remote in time. Experiment 1 proposes methodological improvements over prior studies of temporal discounting that should allow unambiguous fMRI measurement of neural responses to immediate and delayed alternatives, which may invoke different - and possibly competing - neural circuits. Because aging is known to impact functional activation within the frontal-striatal system and associated control behaviors, this proposal hypothesizes that aging will affect the functional connectivity of these networks such that age-related differences in discounting behavior will be correlated with differential activity in the reward and control networks. [unreadable] [unreadable] Decisions involving risk require discounting of uncertain consequences relative to certain ones. Experiment 2 proposes to measure probabilistic discounting using similar procedures employed for time discounting, and to image the same participants. By examining both temporal and probabilistic discounting in the same individuals, we will be able to establish whether they involve distinct neural systems, and whether age affects temporal and probabilistic discounting in the same way. [unreadable] [unreadable] The relationship of individual differences among older adults to choices in economic domains is unknown. Neuropsychological and behavioral measures of executive control will be collected for each participant so that the status of control processes can be related to discounting behavior and brain function in Experiments 1 and 2. In addition, trait measures of individual differences in time preferences, impulsivity, and risk-seeking will be collected in order to determine whether such traits are correlated with functional activation in executive control or reward processing circuits. In addition, the relationship of age differences in discounting to socio-economic and socio-emotional/personality dimensions will be assessed in order to distinguish the effects of age-associated neuro-cognitive changes from environmental and personality effects. [unreadable] [unreadable] Older individuals face important and often complex decisions about retirement, income distribution, insurance, and other financial matters, and there is clear evidence that healthy aging alters many of the psychological capacities and neural systems that are likely to be engaged by such economic decisions. By examining behavioral and neural indices of two types of economic discounting (temporal and probabilistic), this proposal aims to establish whether they involve distinct neural systems, and whether age affects temporal and probabilistic discounting in the same way. In addition, this proposal examines how variability among older adults in executive control function, socio-economic status, and socio-emotional and personality dimensions affect discounting behavior and its neural correlates. [unreadable] [unreadable] [unreadable]