Malá Hana, Andersen Lykke Grønbech, Christensen Rie Friis, Felbinger Anita, Hagstrøm Julie, Meder David, Pearce Hadley, Mogensen Jesper
The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Denmark.
The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Denmark.
Brain Res Bull. 2015 Jul;116:34-44. doi: 10.1016/j.brainresbull.2015.05.006. Epub 2015 May 29.
Within one experiment and one T-maze, we examined the consequences of (i) bilateral lesions of the anteromedial prefrontal cortex (PFC), (ii) bilateral transections of the fimbria-fornix (FF), or (iii) combined lesions of both PFC and FF (COMB) on rats' ability to perform reversal or set-shifting. Postoperatively, the animals were trained to perform a spatial discrimination go-right task. This was followed by (1) a spatial reversal go-left task (reversal learning), or (2) a visual pattern discrimination task (set-shift). Neither single (PFC or FF) lesion nor combined (COMB) lesions affected the animals' ability to acquire the original spatial discrimination task. Regarding the reversal learning, the performance of the PFC and the FF groups was not significantly different from that of the sham operated control animals (Sham). In contrast, animals with combined lesion of both structures were impaired on both error rate and acquisition speed relative to all other groups. Regarding the set-shifting, all lesioned groups were impaired relative to the Sham group both regarding the error rate and the acquisition speed. There was, however, no difference in the degree of impairment between the lesioned groups. We conclude that both the PFC and the hippocampus contributed to the mediation of the reversal learning and set-shifting. During functional recovery of reversal learning, these two structures exhibited a mutual dependency, whilst the functional recovery of set-shifting was mediated by a substrate outside these two structures.
在一项实验和一个T型迷宫中，我们研究了以下三种情况对大鼠执行逆转或转换任务能力的影响：（i）双侧前额叶内侧皮质（PFC）损伤；（ii）双侧穹窿-海马伞（FF）横断；或（iii）PFC和FF联合损伤（COMB）。术后，训练动物执行空间辨别向右任务。随后进行（1）空间逆转向左任务（逆转学习），或（2）视觉模式辨别任务（转换）。单独的（PFC或FF）损伤和联合的（COMB）损伤均未影响动物习得原始空间辨别任务的能力。关于逆转学习，PFC组和FF组的表现与假手术对照组动物（Sham）相比无显著差异。相比之下，相对于所有其他组，两个结构均受损的动物在错误率和习得速度方面均受损。关于转换，所有损伤组在错误率和习得速度方面相对于Sham组均受损。然而，损伤组之间的损伤程度没有差异。我们得出结论，PFC和海马体均参与了逆转学习和转换的调节。在逆转学习的功能恢复过程中，这两个结构表现出相互依赖性，而转换的功能恢复则由这两个结构之外的基质介导。
