Value-Based Decision-Making Following Medial Temporal Lobe Lesions

做出最佳决策取决于对选择价值的理解。一个重要的信息来源 关于选择的价值是先前的经验：积极的经验比消极的经验更有可能是 再次选择。这种基于值的学习一直被认为是试错增量的领域 由皮质-纹状体系统介导的学习。然而，最近的证据表明，在某些情况下， 调节情景记忆的内侧颞叶（MTL）也可能有助于基于价值的学习。 然而，MTL何时以及如何做出贡献却知之甚少。 在这个建议中，我们提出了一种新的方法来概念化MTL在决策中的作用， 该系统的已知计算特性。具体来说，MTL介导的情景记忆 表示是灵活的，并且不仅服务于记忆，而且还服务于可能的新颖场景的表示。 我们假设MTL提供的代表灵活性对决策非常重要 无论何时，价值信息都需要跨不同的体验进行整合。这是一种情况，当1） 价值信息需要更新，作为改变奖励意外事件的结果; 2）当价值信息 不能直接获得，但可以通过经验进行推广; 3）当需要 重新构建。我们系统地研究了这三种MTL病变患者的表现， 范例案例和测试的条件下，基于价值的学习和具体的预测， 决策将受到影响。 包括这项建议在内的各项研究有可能加深我们对多边贸易条约在以下方面的作用的理解： 更高层次的认知并打破过程之间通常假设的严格界限 参与情景记忆和决策。此外，预计这些研究将 重要的临床意义的一系列神经和精神病人群与MTL病理。 了解MTL参与决策的范围和性质不仅有助于了解 这些人群中决策障碍的性质，而且还将指导临床评估， 知情的干预。

Making optimal decisions depends on appreciation of the value of choices. An important source of information about the value of choices is prior experience: Positive experiences are more likely than negative ones to be selected again. Such value-based learning has long been considered the domain of trial-and-error incremental learning mediated by a cortico-striatal system. Recent evidence, however, suggests that in some conditions the medial temporal lobe (MTL), which mediates episodic memory, may also contribute to value-based learning. However, when and how the MTL contributes is poorly understood. In this proposal we put forth a novel way to conceptualize the role of the MTL in decision-making that exploits the known computational characteristics of that system. Specifically, MTL-mediated episodic memory representations are flexible and serve not only memory but also the representation of possible novel scenarios. We postulate that the representational flexibility afforded by the MTL is important for decision-making whenever value information needs to be integrated across distinct experiences. Such is the case when 1) value information needs to be updated as a result of shifting reward contingencies; 2) when value information is not directly available but is generalized across experiences; and 3) when value representations need to be constructed de novo. We systematically examine the performance of patients with MTL lesions in these three paradigmatic cases and test specific predictions about the conditions in which value-based learning and decision-making will be impaired. The studies comprising this proposal have the potential to deepen our understanding of the role of the MTL in higher-level cognition and to break down the stark boundaries commonly assumed between processes involved in episodic memory and decision-making. Further, it is anticipated that these studies will have important clinical implications for a range of neurological and psychiatric populations with MTL pathology. Understanding the scope and nature of MTL involvement in decision-making not only will shed light on the nature of decisional impairments in these populations but also will guide clinical assessment and theoretically informed interventions.