Neurophysiology underlying neural representations of value

描述（由申请人提供）：情绪过程的灵活调节是正常适应行为的标志。也就是说，同样的刺激或行为在一种情况下可以引起积极的情绪反应，但在另一种情况下会引起消极的情绪反应。一般来说，刺激或动作可以通过经验获得情感意义。受试者了解到，以前的“中性”刺激或行动预测奖励或厌恶的事件。因此，激励的意义，或“价值”，刺激可以改变凭借这种经验。在这里，价值可以有正价或负价。对这些刺激的情绪反应可能在很大程度上基于对价值的表征。这项资助旨在探索大脑调整学习刺激值表征的机制。可能参与这些过程的大脑结构包括杏仁核和前额叶皮层，杏仁核长期以来被认为是协调情绪反应的关键结构，前额叶皮层包含两个与杏仁核紧密相连的大脑区域：前扣带皮层和眶额皮层。这些前额区域被认为赋予了快速情绪调整所需的灵活调节类型。在这个补助金，我们将研究两种不同的方式，刺激和/或行动的价值可能会被调整。在目标1中，我们将研究杏仁核和前扣带皮层在逆转学习过程中的作用，即先前学习的两个刺激的关联逆转（或切换）。我们将在我们先前研究杏仁核与眶额皮层的关系的基础上，描述杏仁核和前扣带回之间的关系。在目标2中，我们将使用两个不同的任务来研究受试者如何通过知道如何应用规则来调整他们对刺激值的表征。在一项任务中，实验对象不需要操作性动作，但强化传递确实遵循规则。在第二个任务中，受试者必须根据规则执行正确的操作性动作，以获得强化。第二个任务的目的是阐明前扣带皮层的不同作用，相比，眶额皮层和杏仁核，前扣带已被提出发挥突出的作用，在行动评价，错误监控，并随后调整的行为。这项工作与理解许多精神疾病（如情绪和焦虑症以及精神分裂症）中功能失调的神经回路直接相关。在这些疾病中，杏仁核-前额叶回路的功能障碍可能会损害情绪类型， 正常心理健康所需的灵活性。

DESCRIPTION (provided by applicant): The flexible regulation of emotional processes is a hallmark of normal adaptive behavior. To wit, the same stimulus or action can elicit a positive emotional response in one situation, but a negative one in another situation. In general, stimuli or actions can acquire affective meaning through experience. Subjects learn that previously "neutral" stimuli or actions predict rewarding or aversive events. Thus the motivational significance, or "value", of stimuli can be changed by virtue of this experience. Here, value can have either positive or negative valence. Emotional responses to these stimuli may be based in large part on the representation of value. This grant explores the mechanisms by which the brain adjusts representations of the value of learned stimuli. Brain structures likely to participae in implementing these processes include the amygdala, long recognized as a critical structure in coordinating emotional responses, and the prefrontal cortex, which contains two brain areas densely interconnected with the amygdala: the anterior cingulate and orbitofrontal cortices. These prefrontal areas are thought to confer the type of flexible regulation required for rapid emotional adjustments. In this grant, we will study two different ways in which the value of stimuli and/or actions may be adjusted. In Aim 1, we will study the role of the amygdala and anterior cingulate cortex in a reversal learning procedure, whereby the previously learned associations of two stimuli reverse (or switch). We will characterize the relationship between processing in the amygdala and ACC during this task, building on our prior work studying the amygdala's relationship with OFC. In Aim 2, we will use two different tasks to study how subjects can adjust their representation of the value of a stimulus by knowing how to apply a rule. In one task, no operant actions are required of the experimental subjects, but reinforcement delivery does follow rules. In the second task, subjects must perform the correct operant action according to a rule in order to obtain reinforcement. The second task was designed to elucidate the differential role of the anterior cingulate cortex, as compared to the orbitofrontal cortex and amygdala, as the anterior cingulate has been proposed to play a prominent role in action valuation, error monitoring, and subsequent adjustments of behavior. This work has direct relevance to understanding the neural circuitry that becomes dysfunctional in many psychiatric disorders, such as mood and anxiety disorders, as well as schizophrenia. In those disorders, dysfunction in amygdala- prefrontal circuitry likely impairs the type of emotional flexibility required for normal mental health.