A neural mechanism underlying failure of optimal choice with multiple alternatives.
A neural mechanism underlying failure of optimal choice with multiple alternatives.
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DOI：
10.1038/nn.3649
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发表时间：
2014-03
影响因子：
25
通讯作者：
Rushworth MF
中科院分区：
文献类型：
--
作者：
Chau BK;Kolling N;Hunt LT;Walton ME;Rushworth MF
尽管人们对决策的神经机制有着广泛的兴趣，但大多数研究都集中在两个选项之间的决策上。在这里，我们采用一个生物药理学上合理的决策模型来预测一个关键的决策变量-价值差异信号-编码一个选择比另一个选择好多少，随着第三个但不可用的替代品的价值而变化。该模型预测了令人惊讶的最佳决策失败-在第三个非常差的情况下，在两个选项之间进行选择的难度更大，而不是非常好的选择。预测证实了，第一，通过调查人类的决策，第二，功能性磁共振成像（fMRI）为基础的测量值差异信号的腹内侧前额叶皮层（vmPFC）的vmPFC信号下降的存在下，低价值的第三选择和vmPFC效应大小预测个体差异在次优决策存在多个选择。这种效果与顶叶皮层的分裂正常化形成对比。
Despite widespread interest in neural mechanisms of decision-making most investigations focus on decisions between just two options. Here we adapt a biophysically plausible model of decision-making to predict how a key decision variable–the value difference signal–encoding how much better one choice is than another, changes with the value of a third, but unavailable, alternative. The model predicts surprising failures of optimal decision-making – greater difficulty choosing between two options in the presence of a third very poor, as opposed to very good, alternative. The prediction was borne out, first, by investigation of human decision-making and, second, functional magnetic resonance imaging-(fMRI)-based measurements of value difference signals in ventromedial prefrontal cortex (vmPFC); the vmPFC signal decreased in the presence of low value third alternatives and vmPFC effect sizes predicted individual variation in sub-optimal decision-making in the presence of multiple alternatives. The effect contrasts with that of divisive normalization in parietal cortex.