Bilateral orbital prefrontal cortex lesions in rhesus monkeys disrupt choices guided by both reward value and reward contingency
Bilateral orbital prefrontal cortex lesions in rhesus monkeys disrupt choices guided by both reward value and reward contingency
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DOI：
10.1523/jneurosci.1921-04.2004
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发表时间：
2004-08-25
影响因子：
5.3
通讯作者：
Murray, EA
中科院分区：
文献类型：
--
作者：
Izquierdo, A;Suda, RK;Murray, EA
眶前额叶皮层 (PFo) 作为涉及基于奖励的学习和目标导向行为的网络的一部分运行。为了测试 PFo 是否对于根据预期奖励结果的价值指导行为是必要的，我们比较了四只经过两阶段双侧 PFo 去除的恒河猴和六只未手术的对照动物对强化物贬值的反应，这项任务评估猴子在基础食物的价值发生变化时改变物体选择的能力。为了进行比较，相同的猴子接受了灵活刺激的标准测试——奖励学习，即对象反转学习。相对于对照组，双侧 PFO 切除的猴子在两项独立评估中均表现出强化物贬值效应显着减弱，一项在手术后不久进行，另一项在手术后 19 个月进行。接受手术的猴子的物体反转学习能力也受到损害。然而，这些猴子在获得物体辨别学习问题方面没有受到损害，并且当允许单独选择食物时，无论是在六种不同食物中的食物偏好测试中还是在选择性饱足后，它们的反应都与对照组相似。因此，患有 PFO 损伤的猴子的饱腹感机制和对熟悉食物赋予价值的能力似乎完好无损。结果模式表明，PFo 对于基于预测奖励结果的响应选择至关重要，无论结果的价值是通过情感信号（强化物贬值）还是通过传达奖励偶然性的视觉信号（对象反转学习）来预测。
The orbital prefrontal cortex (PFo) operates as part of a network involved in reward-based learning and goal-directed behavior. To test whether the PFo is necessary for guiding behavior based on the value of expected reward outcomes, we compared four rhesus monkeys with two-stage bilateral PFo removals and six unoperated controls for their responses to reinforcer devaluation, a task that assesses the monkeys' abilities to alter choices of objects when the value of the underlying food has changed. For comparison, the same monkeys were tested on a standard test of flexible stimulus - reward learning, namely object reversal learning. Relative to controls, monkeys with bilateral PFo removals showed a significant attenuation of reinforcer devaluation effects on each of two separate assessments, one performed shortly after surgery and the other similar to 19 months after surgery; the operated monkeys were also impaired on object reversal learning. The same monkeys, however, were unimpaired in acquisition of object discrimination learning problems and responded like controls when allowed to choose foods alone, either on a food preference test among six different foods or after selective satiation. Thus, satiety mechanisms and the ability to assign value to familiar foods appear to be intact in monkeys with PFo lesions. The pattern of results suggests that the PFo is critical for response selection based on predicted reward outcomes, regardless of whether the value of the outcome is predicted by affective signals ( reinforcer devaluation) or by visual signals conveying reward contingency ( object reversal learning).