Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich Zurich, Switzerland ; Division of Humanities and Social Science, California Institute of Technology Pasadena, CA, USA.
Computational and Neural Systems, California Institute of Technology Pasadena, CA, USA.
Front Neurosci. 2014 Mar 18;8:50. doi: 10.3389/fnins.2014.00050. eCollection 2014.
There is widespread interest in identifying computational and neurobiological mechanisms that influence the ability to choose long-term benefits over more proximal and readily available rewards in domains such as dietary and economic choice. We present the results of a human fMRI study that examines how neural activity relates to observed individual differences in the discounting of future rewards during an intertemporal monetary choice task. We found that a region of left dorsolateral prefrontal cortex (dlPFC) BA-46 was more active in trials where subjects chose delayed rewards, after controlling for the subjective value of those rewards. We also found that the connectivity from dlPFC BA-46 to a region of ventromedial prefrontal cortex (vmPFC) widely associated with the computation of stimulus values, increased at the time of choice, and especially during trials in which subjects chose delayed rewards. Finally, we found that estimates of effective connectivity between these two regions played a critical role in predicting out-of-sample, between-subject differences in discount rates. Together with previous findings in dietary choice, these results suggest that a common set of computational and neurobiological mechanisms facilitate choices in favor of long-term reward in both settings.
人们普遍关注的是确定计算和神经生物学机制，这些机制影响着在饮食和经济选择等领域中选择长期利益而不是更接近和更容易获得的奖励的能力。我们介绍了一项人类 fMRI 研究的结果，该研究考察了神经活动如何与在跨期货币选择任务中观察到的未来奖励贴现的个体差异相关。我们发现，在控制了这些奖励的主观价值之后，左侧背外侧前额叶皮层（dlPFC）BA-46 区域在被试选择延迟奖励的试验中更活跃。我们还发现，来自 dlPFC BA-46 到与刺激价值计算广泛相关的腹内侧前额叶皮层（vmPFC）区域的连接性在选择时增加，尤其是在被试选择延迟奖励的试验中。最后，我们发现，这两个区域之间的有效连接的估计在预测样本外、被试之间的折扣率差异方面起着关键作用。结合以前在饮食选择方面的发现，这些结果表明，在这两种情况下，一组共同的计算和神经生物学机制有助于做出有利于长期奖励的选择。
