The role of stress neuromodulators in decision making under risk

偶然的情感状态，即，与手头的决定无关的情感状态可以影响决策。急性压力就是这样一种情感状态，是决策过程的一个强有力的背景调节器。在生理和神经激素变化方面，压力反应已经得到了很好的表征：暴露于压力会引起一系列自主神经、内分泌和行为反应。生理应激反应由下丘脑-垂体-肾上腺（HPA）轴和蓝斑去甲肾上腺素（LC-NA）系统介导，皮质醇和去甲肾上腺素（NE）是它们的终产物。有令人信服的证据表明，应激激素皮质醇和NE影响认知过程。然而，到目前为止，只有很少的研究使用药理学方法来说明应激神经调节剂对决策的作用，并且由于实验设计的差异，这些研究几乎没有可比性，例如，使用的决策任务。此外，到目前为止，压力对决策影响的神经基础还没有研究，因此，需要进行以下研究：1）系统地区分最重要的压力神经调节剂NE和皮质醇的影响，2）使用区分不同决策过程的任务，如风险态度和损失厌恶，以解开这些神经调节剂及其神经相关物的潜在不同作用。本研究计划旨在探讨主要的压力神经调质NE及皮质醇在不同风险决策过程中的作用。为此，我们将结合联合收割机精确的药理学刺激、行为建模和功能磁共振成像方法，系统地解开应激激素对风险态度和损失厌恶的影响，以及它们与处理主观价值和风险的神经相关物的关系。我们的研究计划包括两项研究。在研究1中，我们将在行为、计算和神经水平上研究去甲肾上腺素能激活和阻断对风险决策的作用。在研究2中，我们将使用类似的方法来研究皮质醇与和没有额外的去甲肾上腺素能激活对风险决策的影响。

Incidental affective states, i.e., affective states that are unrelated to the decision at hand, can influence decision making. Acute stress is such an affective state and is a powerful contextual modulator of decision-making processes. It appeared that after stress exposure, individuals make riskier decisions.In terms of physiological and neurohormonal changes, the stress response has been well characterized: Exposure to stress elicits an array of autonomic, endocrine, and behavioral responses. The physiological stress response is mediated by the hypothalamic-pituitary adrenal (HPA) axis and the locus coeruleus noradrenergic (LC-NA) system with cortisol and norepinephrine (NE) as their end products. There is compelling evidence that the stress hormones cortisol and NE influence cognitive processes. However, only very few studies so far used pharmacological approaches to specify the role of stress neuromodulators on decision making and these studies are hardly comparable due to differences in the experimental design, e.g., the decision making task used. Furthermore, the neural underpinnings of stress effects on decision making are uninvestigated so far.Thus, studies are needed which 1) systematically differentiate the effects of the most important stress neuromodulators NE and cortisol, and 2) use tasks that differentiate different decision making processes, such as risk attitude and loss aversion to disentangle potentially different effects of these neuromodulators and their neural correlates.The aim of the proposed project is to clarify the role of the major stress neuromodulators, NE and cortisol, in their contribution to different processes related to decision making under risk. To this end, we will combine precise pharmacological stimulation, behavioral modeling, and fMRI methods to systematically disentangle the effects of stress hormones on risk attitudes and loss aversion as well as their relation to neural correlates of processing subjective value and risk. Our research program comprises two studies. In study 1, we will examine the role of noradrenergic activation and blockade on decision making under risk at the behavioral, computational, and neural level. In study 2, we will use a similar approach to investigate the effects of cortisol with and without additional noradrenergic activation on decision making under risk.