Salience-Driven Value Construction for Adaptive Choice under Risk
Salience-Driven Value Construction for Adaptive Choice under Risk
复制标题
DOI：
10.1523/jneurosci.2522-18.2019
复制
发表时间：
2018-12
期刊：
影响因子：
--
通讯作者：
Mehran Spitmaan;Emily Chu;A. Soltani
中科院分区：
文献类型：
--
作者：
Mehran Spitmaan;Emily Chu;A. Soltani
我们在现实生活中所面临的决定本质上是有风险的，可能会导致许多可能的结果之一。然而，我们对风险选择的大部分了解都是基于只有两种可能结果的研究（简单的赌博），所以我们仍然不清楚大脑是如何为现实生活中面临的更复杂的风险选择构建奖励值的。为了解决这个问题，我们将实验和建模方法结合起来，研究了男性和女性受试者在简单赌博和三结果赌博之间的选择。我们发现，受试者通过将奖励大小和概率函数相乘来评估三结果赌博的个人结果。然而，为了构建每次赌博的总体价值，大多数受试者根据奖励大小或概率对可能的结果进行不同的加权。这些结果揭示了在评估复杂赌博时如何处理奖励信息之间的新分离：每个结果的评估是基于奖励信息的组合，而可能结果的权重主要依赖于单个奖励信息。我们表明，可能结果的不同权重可以使受试者更容易、更快速地做出决定。总之，我们的研究结果揭示了一种合理的机制，即在可能的奖励幅度或概率方面，显著性如何影响复杂赌博的主观价值构建。他们还指出了可分离的神经机制，说明奖励价值如何控制选择和注意力，从而允许在风险下做出更具适应性的决策。现实生活中的决策本质上是有风险的，可能会导致许多可能的结果之一，但大脑是如何整合所有这些结果的信息来做出决策的呢？为了解决这个问题，我们使用各种计算模型研究了具有多种结果的赌博对之间的选择。我们发现，受试者通过奖励大小和概率的乘积函数来评估个体结果。然而，为了构建每次赌博的总体价值，他们根据奖励大小或概率对可能的结果进行了不同的加权。通过这样做，他们能够更容易、更快速地做出决定。我们的研究结果说明，就可能的奖励幅度或概率而言，显著性如何影响更适应性选择的主观价值构建。
Decisions we face in real life are inherently risky and can result in one of many possible outcomes. However, most of what we know about choice under risk is based on studies that use options with only two possible outcomes (simple gambles), so it remains unclear how the brain constructs reward values for more complex risky options faced in real life. To address this question, we combined experimental and modeling approaches to examine choice between pairs of simple gambles and pairs of three-outcome gambles in male and female human subjects. We found that subjects evaluated individual outcomes of three-outcome gambles by multiplying functions of reward magnitude and probability. To construct the overall value of each gamble, however, most subjects differentially weighted possible outcomes based on either reward magnitude or probability. These results reveal a novel dissociation between how reward information is processed when evaluating complex gambles: valuation of each outcome is based on a combination of reward information whereas weighting of possible outcomes mainly relies on a single piece of reward information. We show that differential weighting of possible outcomes could enable subjects to make decisions more easily and quickly. Together, our findings reveal a plausible mechanism for how salience, in terms of possible reward magnitude or probability, can influence the construction of subjective values for complex gambles. They also point to separable neural mechanisms for how reward value controls choice and attention to allow for more adaptive decision making under risk. SIGNIFICANCE STATEMENT Real-life decisions are inherently risky and can result in one of many possible outcomes, but how does the brain integrate information from all these outcomes to make decisions? To address this question, we examined choice between pairs of gambles with multiple outcomes using various computational models. We found that subjects evaluated individual outcomes by multiplying functions of reward magnitude and probability. To construct the overall value of each gamble, however, they differentially weighted possible outcomes based on either reward magnitude or probability. By doing so, they were able to make decisions more easily and quickly. Our findings illustrate how salience, in terms of possible reward magnitude or probability, can influence the construction of subjective values for more adaptive choice.