Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
J Neurosci. 2011 Jan 5;31(1):118-25. doi: 10.1523/JNEUROSCI.3214-10.2011.
Decision-making is often viewed as a two-stage process, where subjective values are first assigned to each option and then the option of the highest value is selected. Converging evidence suggests that these subjective values are represented in the striatum and medial prefrontal cortex (MPFC). A separate line of evidence suggests that activation in the same areas represents the values of rewards even when choice is not required, as in classical conditioning tasks. However, it is unclear whether the same neural mechanism is engaged in both cases. To address this question we measured brain activation with functional magnetic resonance imaging while human subjects passively viewed individual consumer goods. We then sampled activation from predefined regions of interest and used it to predict subsequent choices between the same items made outside of the scanner. Our results show that activation in the striatum and MPFC in the absence of choice predicts subsequent choices, suggesting that these brain areas represent value in a similar manner whether or not choice is required.
决策通常被视为一个两阶段的过程,首先为每个选项分配主观价值,然后选择价值最高的选项。越来越多的证据表明,这些主观价值是由纹状体和内侧前额叶皮层(MPFC)来表示的。另一条证据表明,即使在不需要选择的情况下,例如在经典条件作用任务中,同一区域的激活也代表着奖励的价值。然而,目前尚不清楚在这两种情况下是否使用了相同的神经机制。为了解决这个问题,我们在人类受试者被动观察单个消费品时使用功能磁共振成像测量大脑激活。然后,我们从预定义的兴趣区域中采样激活,并使用它来预测在扫描仪外对同一物品进行的后续选择。我们的结果表明,在没有选择的情况下,纹状体和 MPFC 的激活可以预测随后的选择,这表明这些大脑区域以相似的方式代表价值,无论是否需要选择。