Lesions of orbitofrontal cortex and basolateral amygdala complex disrupt acquisition of odor-guided discriminations and reversals
Lesions of orbitofrontal cortex and basolateral amygdala complex disrupt acquisition of odor-guided discriminations and reversals
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DOI：
10.1101/lm.55203
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发表时间：
2003-03-01
影响因子：
2
通讯作者：
Gallagher, M
中科院分区：
文献类型：
--
作者：
Schoenbaum, G;Setlow, B;Gallagher, M
最近的工作表明，眼眶水平皮质(OFC)和杏仁核基底外侧复合体(ABL)都参与了线索与预测结果相关的过程。为了检验这些结构在辨别学习中的各自作用，对双侧假手术或OFC或ABL神经毒性损毁的大鼠进行了一系列2-气味辨别问题的训练，在口渴刺激的Go-Go-Go任务中。在获得了一系列气味问题后，对大鼠进行了一系列反转最终气味问题的训练。通过监测选择行为的准确性，以及通过测量气味采样后对液体结果做出反应的潜伏期来评估每个问题的表现。在辨别学习过程中，两组大鼠都有相似的缺陷，在学习过程中没有表现出反应潜伏期的正常变化，同时相对于对照组表现出正常的选择行为。选择行为只在训练的反转阶段受到影响，在该阶段，OFC和ABL损伤产生(])明显的缺陷。ABL损伤的大鼠在第一次逆转(S1-/S2+)时受损，但在获得恢复到原始气味结果环境(S1+/S2-)时没有受损，而OFC损伤的大鼠在两种类型的逆转中都受损。这些发现表明，OFC和ABL在使用支持正常歧视绩效的激励信息方面扮演着部分重叠的角色。
Recent work indicates that both orbitotrontal cortex (OFC) and the basolateral complex of the amygdala (ABL) are involved in processes by which cues are associated with predicted outcomes. To examine the respective roles of these structures in discrimination learning, rats with bilateral sham or neurotoxic lesions of either OFC or ABL were trained on a series of four 2-odor discrimination problems in a thirst-motivated go, no-go task. After acquisition of the series of odor problems, the rats were trained on serial reversals of the final odor problem. Performance on each problem was assessed by monitoring accuracy of choice behavior, and also by measuring latency to respond for fluid outcomes after odor sampling. During discrimination learning, rats in both lesioned groups had similar deficits, failing to show normal changes in response latency during learning, while at the same time exhibiting normal choice behavior relative to controls. Choice behavior was affected only during the reversal phase of training, in which OFC and ABL lesions produce(] distinctive deficits. Rats with ABL lesions were impaired on the first reversal (S1-/S2+), but were unimpaired at acquiring a reversal back to the original odor-outcome contigencies (S1+/S2-), whereas rats with OFC lesions were impaired on both types of reversals. These findings suggest that OFC and ABL serve partially overlapping roles in the use of incentive information that supports normal discrimination performance.