It's not fair! Behavioral and neural evidence that equity influences social economic decisions in healthy older adults

This dissertation examines how aging affects economic decision‑making and its neural bases. Compared with younger adults (21–45), older adults (65–85) reported less impulsive/sensation‑seeking behavior and were less willing to take social risks. In social economic tasks, older adults made fairer allocations and more often rejected both generous and unfair offers, yielding lower payoffs; by contrast, age groups performed similarly on non‑social risk and delay tasks. fMRI during the Ultimatum Game showed that older adults exhibited greater anterior insula and dorsolateral prefrontal cortex activity to generous and unfair (but not fair) offers, while both age groups showed heightened amygdala responses to human versus computer proposers. Findings suggest aging preferentially alters social decisions, with increased emphasis on fairness and greater reliance on rule‑based, affectively supported strategies.