Balancing reward and work: Anticipatory brain activation in NAcc and VTA predict effort differentially
Balancing reward and work: Anticipatory brain activation in NAcc and VTA predict effort differentially
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DOI：
10.1016/j.neuroimage.2014.07.060
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发表时间：
2014-11-15
期刊：
影响因子：
5.7
通讯作者：
Smolka, Michael N.
中科院分区：
文献类型：
--
作者：
Kroemer, Nils B.;Guevara, Alvaro;Smolka, Michael N.
复杂的决策涉及到对未来回报的预期，即为获得回报而付出的努力。使用功能磁共振成像，我们调查了50名参与者，他们在运动反应阶段开始前使用了一项工具动机任务来提示强化水平。我们从中皮质边缘系统的感兴趣区域（ROI）提取时间过程，并使用三级层次模型在逐个试验的基础上分离预期脑反应、预测值和随后的努力。虽然所有roi值均为正，但较高的伏隔核（NAcc）预期激活和较低的腹侧被盖区/黑质（VTA/SN）预期激活预测了较高的努力。此外，背纹状体的预期激活预测平均努力，而杏仁核的高激活预测高于平均努力。因此，预期激活包含了需要努力才能获得的强化的欲望驱动。我们的研究结果支持NAcc作为主要枢纽的作用，该枢纽由在每个试验基础上运行的突出网络支持，而背纹状体包含习惯性反应。(c) 2014 Elsevier Inc.版权所有。
Complex decision-making involves anticipation of future rewards to bias effort for obtaining it. Using fMRI, we investigated 50 participants employing an instrumental-motivation task that cued reinforcement levels before the onset of the motor-response phase. We extracted time courses from regions of interest (ROI) in the mesocorticolimbic system and used a three-level hierarchical model to separate anticipatory brain responses predicting value and subsequent effort on a trial-by-trial basis. Whereas all ROIs scaled positively with value, higher effort was predicted by higher anticipatory activation in nucleus accumbens (NAcc) but lower activation in ventral tegmental area/substantia nigra (VTA/SN). Moreover, anticipatory activation in the dorsal striatum predicted average effort whereas higher activation in the amygdala predicted above-average effort. Thus, anticipatory activation entails the appetitive drive towards reinforcement that requires effort in order to be obtained. Our results support the role of NAcc as the main hub supported by the salience network operating on a trial-by-trial basis, while the dorsal striatum incorporates habitual responding. (c) 2014 Elsevier Inc. All rights reserved.