The effects of age on reward magnitude processing in the monetary incentive delay task
The effects of age on reward magnitude processing in the monetary incentive delay task
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DOI：
10.1016/j.neuroimage.2019.116368
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发表时间：
2020-02-15
期刊：
影响因子：
5.7
通讯作者：
Li, Chiang-Shan R.
中科院分区：
文献类型：
--
作者：
Dhingra, Isha;Zhang, Sheng;Li, Chiang-Shan R.
以前的研究表明，年龄相关的奖赏导向行为和大脑过程中的差异支持年龄效应。然而，目前还不清楚年龄如何影响奖赏大小的处理。在这里，有54名志愿者(22-74岁)参加了货币激励延迟任务(MIDT)，他们有明确的提示($1，(SIC)1，或NIL)和对WIN的定时反应，我们描述了预期和反馈过程中的大脑激活以及年龄对这些区域激活的影响。在行为上，年龄与美元试验和CINT试验之间的反应时(RT)差异较小有关，这是因为对美元试验的反应较慢；即，年龄与RT美元-RT CENT呈正相关，RT为零作为协变量。年龄和RT差异($1-(SIC)1)都与期望1美元与(SIC)1奖励时右侧尾状头、右侧前岛叶、辅助运动区(SMA)/SMA前区、视觉皮质、海马旁回、右侧额中上回和左侧初级运动皮质的激活减少有关。此外，这些区域活动在年龄对RT差异的影响中起中介作用。在对结果的反应中，年龄与区域对美元对美分损失的激活减少有关，但只是因为与年龄有关的对美分损失的反应更高。总而言之，这些发现表明，年龄相关的人对奖励幅度的敏感度存在差异。在预期赢得大笔奖励的过程中，大脑反应较低，而对小损失的结果反应较高，因此年龄对奖励的大小产生了一种狭隘的敏感性。
Previous studies have suggested age-related differences in reward-directed behavior and cerebral processes in support of the age effects. However, it remains unclear how age may influence the processing of reward magnitude. Here, with 54 volunteers (22-74 years of age) participating in the Monetary Incentive Delay Task (MIDT) with explicit cues ($1, (sic)1, or nil) and timed response to win, we characterized brain activations during anticipation and feedback and the effects of age on these regional activations. Behaviorally, age was associated with less reaction time (RT) difference between dollar and cent trials, as a result of slower response to the dollar trials; i.e., age was positively correlated with RT dollar - RT cent, with RT nil as a covariate. Both age and the RT difference ($1 - (sic)1) were correlated with diminished activation of the right caudate head, right anterior insula, supplementary motor area (SMA)/pre-SMA, visual cortex, parahippocampal gyrus, right superior/middle frontal gyri, and left primary motor cortex during anticipation of $1 vs. (sic)1 reward. Further, these regional activities mediated the age effects on RT differences. In responses to outcomes, age was associated with decreases in regional activations to dollar vs. cent loss but only because of higher age-related responses to cent losses. Together, these findings suggest age-related differences in sensitivity to the magnitude of reward. With lower cerebral responses during anticipation to win large rewards and higher responses to outcomes of small loss, aging incurs a constricted sensitivity to the magnitude of reward.