Roesch Matthew R, Calu Donna J, Burke Kathryn A, Schoenbaum Geoffrey
Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Ann N Y Acad Sci. 2007 May;1104:21-34. doi: 10.1196/annals.1390.001. Epub 2007 Mar 7.
Animals prefer a small, immediate reward over a larger delayed reward (time discounting). Lesions of the orbitofrontal cortex (OFC) can either increase or decrease the breakpoint at which animals abandon the large delayed reward for the more immediate reward as the delay becomes longer. Here we argue that the varied effects of OFC lesions on delayed discounting reflect two different patterns of activity in OFC; one that bridges the gap between a response and an outcome and another that discounts delayed reward. These signals appear to reflect the spatial location of the reward and/or the action taken to obtain it, and are encoded independently from representations of absolute value. We suggest a dual role for output from OFC in both discounting delayed reward, while at the same time supporting new learning for them.
动物更喜欢小的即时奖励而非大的延迟奖励（时间折扣）。眶额叶皮层（OFC）损伤可能会增加或减少断点，随着延迟时间变长，动物会为了更即时的奖励而放弃大的延迟奖励。在这里，我们认为OFC损伤对延迟折扣的不同影响反映了OFC中两种不同的活动模式；一种是弥合反应与结果之间差距的模式，另一种是对延迟奖励进行折扣的模式。这些信号似乎反映了奖励的空间位置和/或为获得奖励所采取的行动，并且是独立于绝对值表征进行编码的。我们提出OFC输出在对延迟奖励进行折扣的同时，还支持对它们的新学习，具有双重作用。
