Lesions of the orbital prefrontal cortex impair the formation of attentional set in rats
Lesions of the orbital prefrontal cortex impair the formation of attentional set in rats
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DOI：
10.1111/j.1460-9568.2012.08141.x
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发表时间：
2012-08-01
影响因子：
3.4
通讯作者：
Brown, Verity J.
中科院分区：
文献类型：
--
作者：
Chase, E. Alexander;Tait, David S.;Brown, Verity J.
在大鼠中，逆转学习障碍通常发生在眶前额叶皮层（OFC）损伤后，而内侧前额叶皮层损伤则会损害注意力转移。在人类、猴子和老鼠中也有类似的分离。然而，这两种行为灵活性的表现可能具有共同的认知过程。目前的研究测试了OFC（一个整合预期和实际结果的区域，以表明环境中哪些线索可以预测奖励）的损伤会损害注意力集的形成以及损害反转学习的假设。我们比较了受损大鼠和对照组大鼠在两组转移任务中的表现。我们使用的第一个任务，即4ID任务，没有反转阶段，但在外维度转移阶段之前有多个内维度获取，以评估集合形成和集合转移。第二个任务是标准的内维/外维7阶段任务，其中包括每个复合习得后的反转学习阶段。与对照组相比，损伤大鼠在4ID任务中形成注意集的速度较慢。当他们形成一个集合时，他们需要更多的试验来完成外维度转移阶段。在7个阶段的任务中，我们重复了之前的发现，逆转学习受损，转移成本降低。我们将这些发现解释为在意外结果后识别相关线索的单一缺陷，这支持了最近的OFC功能模型。我们的研究结果挑战了OFC对行为灵活性的贡献仅限于逆向学习的假设。
In rats, reversal learning impairments are commonly reported after lesions of the orbital prefrontal cortex (OFC), in contrast to the effect of lesions of the medial prefrontal cortex, which impair attentional set-shifting. Comparable dissociations have also been reported in humans, monkeys and mice. However, these two manifestations of behavioural flexibility may share common cognitive processes. The present study tested the hypothesis that lesions of the OFC (an area that integrates expected and actual outcomes to signal which cues in the environment predict reward) would impair the formation of attentional set as well as impairing reversal learning. We compared the performance of lesioned and control rats on two set-shifting tasks. The first task we used, the 4ID task, had no reversal stages, but multiple intradimensional acquisitions before the extradimensional shift stage, to assess set-formation as well as set-shifting. The second task was the standard intradimensional/extradimensional 7-stage task, which includes reversal learning stages after each compound acquisition. Compared with controls, lesioned rats were slower to form attentional set on the 4ID task. When they did form a set, they required more trials to complete the extradimensional shift stage. On the 7-stage task, we replicated our previous finding of impaired reversal learning and reduced shift-costs. We interpret these findings as reflecting a single deficit in identifying relevant cues after unexpected outcomes, which supports recent models of OFC function. Our findings challenge the assumption that the contribution of the OFC to behavioural flexibility is limited to reversal learning.