Department of Psychology, Southern Methodist University, Dallas, TX, USA.
Department of Psychology, Boston College, Chestnut Hill, MA, USA.
Neurobiol Aging. 2020 Jun;90:1-12. doi: 10.1016/j.neurobiolaging.2020.02.013. Epub 2020 Feb 21.
Both younger and older adults prioritize reward-associated stimuli in memory, but there has been little research on possible age differences in the neural mechanisms mediating this effect. In the present study, we examine neural activation and functional connectivity in healthy younger and older adults to test the hypothesis that older adults would engage prefrontal regions to a greater extent in the service of reward-enhanced memory. While undergoing MRI, target stimuli were presented after high- or low-reward cues. The cues indicated the reward value for successfully recognizing the stimulus on a memory test 24 hours later. We replicated prior findings that both older and younger adults had better memory for high- compared to low-reward stimuli. Critically, in older but not younger adults, this enhanced subsequent memory for high-reward items was supported by greater connectivity between the caudate and bilateral inferior frontal gyrus. The findings add to the growing literature on motivation-cognition interactions in healthy aging and provide novel findings of the neural underpinnings of reward-motivated encoding.
无论是年轻人还是老年人，在记忆中都优先考虑与奖励相关的刺激，但对于这种效应的神经机制中可能存在的年龄差异，研究甚少。在本研究中，我们检查了健康的年轻和老年成年人的神经激活和功能连接，以检验以下假设：老年人将更大程度地利用前额叶区域来增强与奖励相关的记忆。在进行 MRI 时，目标刺激在高或低奖励线索后呈现。这些线索表明，在 24 小时后的记忆测试中成功识别刺激的奖励价值。我们复制了先前的发现，即与低奖励刺激相比，无论是老年人还是年轻人，对高奖励刺激的记忆都更好。关键的是，在老年人中，但不是在年轻人中，这种对高奖励项目的增强的后续记忆，是由尾状核和双侧下额回之间更大的连接支持的。这些发现增加了关于健康衰老中动机认知相互作用的文献，并提供了奖励动机编码的神经基础的新发现。
