The aging brain undergoes numerous changes that affect cognitive and motivational networks. As we age, our reward system remains crucial to meet basic needs and adapt to our evolving environment. Research suggests that the reward system is better preserved in older adults compared to other cognitive functions. To understand how the reward system maintains stability in aging, scientists conducted a study using a well-known reward task and EEG measurements. They focused on cortical reward-related network connectivity and found that older adults exhibited lower modulation of reward-related connectivity, relying more on posterior and right-lateralized brain areas. Interestingly, their connectivity patterns differed from younger adults, with typically higher connectivity during non-reward conditions. These findings challenge previous models of cognitive aging and suggest that the reward system has unique compensatory mechanisms rooted in its early evolutionary origin. This study sheds light on the intricate workings of the cortical reward network in healthy aging, offering valuable insights for future research.

Healthy aging is accompanied by multi-faceted changes. Especially within the brain, healthy aging exerts substantial impetus on core parts of cognitive and motivational networks. Rewards comprise basic needs, such as food, sleep, and social contact. Thus, a functionally intact reward system remains indispensable for elderly people to cope with everyday life and adapt to their changing environment. Research shows that reward system function is better preserved in the elderly than most cognitive functions. To investigate the compensatory mechanisms providing reward system stability in aging, we employed a well-established reward paradigm (Monetary Incentive Delay Task) in groups of young and old participants while undergoing EEG measurement. As a new approach, we applied EEG connectivity analyses to assess cortical reward-related network connectivity. At the behavioral level, our results confirm that the function of the reward system is preserved in old age. The mechanisms identified for maintaining reward system function in old age do not fit into previously described models of cognitive aging. Overall, older adults exhibit lower reward-related connectivity modulation, higher reliance on posterior and right-lateralized brain areas than younger adults, and connectivity modulation in the opposite direction than younger adults, with usually greater connectivity during non-reward compared to reward conditions. We believe that the reward system has unique compensatory mechanisms distinct from other cognitive functions, probably due to its etymologically very early origin. In summary, this study provides important new insights into cortical reward network connectivity in healthy aging.

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