New research suggests why people are often torn between impulsively choosing immediate rewards or more deliberatively planning for the future: human decision-making is influenced by the interactions of two distinct systems in the brain which are often at odds.

Study participants made choices between immediate and longer-term rewards. When participants chose between incentives that included an immediate reward, fMRI scans indicated heightened activity in parts of the brain, such as the limbic system, that are associated with emotional decision making. In contrast, deliberative and analytic regions of the brain, such as the prefrontal and parietal cortex, were activated by all decisions, even those that did not involve an immediate reward. However, when participants resisted immediate rewards and instead chose delayed rewards, activity was particularly strong in these deliberative areas of the brain.

NIH NIA news release