To blow hot and cold under stress - neurohormonal moderators of revealed preferences

揭示偏好理论为从可观察到的选择中推断消费者偏好提供了一个正式的框架。它可以从过去揭示的偏好中预测样本外的选择，前提是偏好在观察的时间段内是稳定的。然而，在心理神经内分泌学文献中有证据表明，除其他外，经济偏好取决于消费者的神经激素状态，这种状态是动态的、灵活的和时变的，但外部观察者看不到，而且部分无法通过内省获得。例如，在之前的几轮融资中，我们已经表明，心理社会压力，或对应激神经调节剂皮质醇(Cortisol)和去甲肾上腺素(NA)的心理药理操纵，以一种系统的、可预测的、但高度依赖于时间的方式改变了利他、他者的偏好。因此，由于偏好可能会随着荷尔蒙的波动而迅速而剧烈地变化，选择可能会变得不一致；即，在某个时间点显示的偏好可能不能用来预测压力较大的消费者未来的偏好，即使在最初揭示偏好的几分钟后也是如此。然而，这绝不是确定无疑的知识，同样可信的是，压力只会短暂地导致更大的选择变异性，这只会被揭示的偏好标记(模糊手)归类为决策噪音增加--这一现象不会对揭示偏好理论构成严重挑战。本研究旨在评估心理社会压力(实验1)或皮质醇和去甲肾上腺素的心理药理调节(实验2)对利他主义给予的影响是否会导致显著的不一致选择。选择(In)一致性将使用揭示偏好理论提供的严格的理性概念和数量基准(即选择一致性)来衡量。为此，我们将采用改进的独裁者游戏，参与者在自己和另一个人之间做出资源分配决定。我们操纵预算(要分享的捐赠)和捐赠成本(参与者将钱捐给对方必须支付的“交易成本”)。我们预测，分别在心理社会压力或心理药理学挑战后，给予决定的一致性比控制操作后更不一致。我们还预计，这种内部不一致性的增加不仅仅是由于放大的决策噪音，而是由于社会偏好的真正变化，如分别在压力或药物作用之前和之后改变的效用函数。我们的结果将对我们理解荷尔蒙状态变化的作用，特别是压力效应对经济合理性的影响具有重要意义。

Revealed preference theory provides a formal framework to infer consumer preferences from observable choices. It can predict out-of-sample choices from past revealed preferences under the assumption that preferences are stable over the time period of observation. However, there is evidence in the psychoneuroendocrinological literature that economic preferences depend, among others, on the neurohormonal state of the consumer, which is dynamic, flexible, and time-varying, but non-visible for an external observer, and partly inaccessible by introspection. For example, in the previous funding rounds, we have shown that psychosocial stress, or psychopharmacological manipulation of the stress neuromodulators cortisol (CORT) and noradrenaline (NA), altered altruistic, other-regarding preferences in a systematic, predictable, yet highly time-dependent way. By consequence, since preferences may change rapidly and drastically with hormonal fluctuations, choices may become inconsistent; i.e., a revealed preference at one point in time may not serve to predict a stressed consumer’s future preference even minutes after the preference has been initially revealed. However, this is by no means assured knowledge, it is equally plausible that stress only transiently results in larger choice variability that would merely be classified as increased decision noise by revealed preference markers (fuzzy hands) – a phenomenon that would not pose a serious challenge to revealed preference theory. The aim of this grant proposal is to evaluate, in participants of both genders, whether the effects of psychosocial stress (experiment 1) or psychopharmacological modulation of CORT and NA (experiment 2) on altruistic giving induce significantly inconsistent choice. Choice (in)consistency will be measured with the rigorous conceptual and quantitative benchmark of rationality (i.e., choice consistency) provided by revealed preference theory. To this end, we will adopt a modified dictator game in which participants make resource allocation decisions between themselves and another person. We manipulate the budget (the endowment to be shared) and the costs of giving (a “transaction cost” that participants have to pay to give money to the other). We predict that giving decisions are more inconsistent after psychosocial stress, or psychopharmacological challenge respectively, than after control manipulations. We furthermore expect that this increase in internal inconsistency is not (only) due to amplified decision noise, but due to genuine changes in social preferences, as measured by altered utility functions before vs. after stress, or drug action respectively. Our results will have implications for our understanding of the role of hormonal state changes in general, and stress effects in particular, on economic rationality.