原发性奖励和继发性奖励在工作记忆过程中对神经活动动态有不同的调节作用。

BACKGROUND: Cognitive control and working memory processes have been found to be influenced by changes in motivational state. Nevertheless, the impact of different motivational variables on behavior and brain activity remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: The current study examined the impact of incentive category by varying on a within-subjects basis whether performance during a working memory task was reinforced with either secondary (monetary) or primary (liquid) rewards. The temporal dynamics of motivation-cognition interactions were investigated by employing an experimental design that enabled isolation of sustained and transient effects. Performance was dramatically and equivalently enhanced in each incentive condition, whereas neural activity dynamics differed between incentive categories. The monetary reward condition was associated with a tonic activation increase in primarily right-lateralized cognitive control regions including anterior prefrontal cortex (PFC), dorsolateral PFC, and parietal cortex. In the liquid condition, the identical regions instead showed a shift in transient activation from a reactive control pattern (primary probe-based activation) during no-incentive trials to proactive control (primary cue-based activation) during rewarded trials. Additionally, liquid-specific tonic activation increases were found in subcortical regions (amygdala, dorsal striatum, nucleus accumbens), indicating an anatomical double dissociation in the locus of sustained activation. CONCLUSIONS/SIGNIFICANCE: These different activation patterns suggest that primary and secondary rewards may produce similar behavioral changes through distinct neural mechanisms of reinforcement. Further, our results provide new evidence for the flexibility of cognitive control, in terms of the temporal dynamics of activation.

背景：认知控制和工作记忆过程受到动机状态变化的影响。然而，不同激励变量对行为和大脑活动的影响仍不清楚。

方法/主要发现：本研究通过在工作记忆任务中以不同的方式改变奖励类别（即次级（货币）或主要（液体）奖励），来考察奖励类别的影响。通过采用一种实验设计，可以隔离持续和瞬态效应，从而研究动机-认知相互作用的时间动态。在每种激励条件下，绩效都得到了显著且相当的提高，而激励类别之间的神经活动动态则有所不同。在货币奖励条件下，与认知控制相关的主要右侧区域（包括前额叶皮层、背外侧前额叶皮层和顶叶皮层）的活动呈现出紧张性激活增加。在液体奖励条件下，相同的区域在没有奖励的试验中表现出从反应性控制模式（主要基于探针的激活）到在有奖励的试验中表现出主动性控制（主要基于线索的激活）的瞬态激活转变。此外，在皮质下区域（杏仁核、背侧纹状体、伏隔核）中发现了特定于液体的紧张性激活增加，这表明持续激活的位置存在解剖学上的双重分离。

结论/意义：这些不同的激活模式表明，初级和次级奖励可能通过不同的强化神经机制产生相似的行为变化。此外，我们的结果为认知控制的灵活性提供了新的证据，涉及激活的时间动态。