UDEL Subproject 3

对行为做出适应性改变以应对环境变化对生存至关重要，因此很可能通过分布式神经网络中的复杂相互作用来调节。与行为灵活性有关的一个大脑区域是内侧前额叶皮质(MPFC)。这一区域的损害会导致执行功能、计划和工作记忆的损害，这些都是行为灵活性的重要组成部分。记录研究表明，单个mPFC神经元在需要在时间间隔内保留信息的任务的延迟期内表现出较高的放电频率，例如延迟匹配/不匹配到样本，这表明mPFC神经元参与了工作记忆。其他研究表明，mPFC活动在反应执行之前显示出预期的引发率增加，这表明它在计划即将采取的行动中发挥了作用。目前的建议的目标是通过比较mPFC损伤的影响和mPFC单个神经元在两个类似任务中的放电模式来分离mPFC参与工作记忆的其他功能：一个任务需要工作记忆，另一个任务不需要工作记忆。此外，这些任务的颠倒将揭示mPFC在行为灵活性中的作用。最后，我们将通过灭活海马区并同时记录任务获得、执行和逆转过程中的mPFC单个神经元来研究海马区和mPFC之间的相互作用。这些结果将有助于更好地理解mPFC在适应行为中的作用，无论是单独的还是与海马体一起的。

Making adaptive changes in behavior in response to environmental change is essential to survival and therefore is likely to be mediated by complex interactions within a network of distributed neural circuits. One brain region that has been implicated in behavioral flexibility is the medial prefrontal cortex (mPFC). Damage to this region causes impairments in executive function, planning, and working memory, which are all important components of behavioral flexibility. Recording studies have shown that single mPFC neurons show elevated firing rates during the delay period of tasks that require the retention of information over a temporal gap, such as delayed-match/nonmatch-to-sample, suggesting that mPFC neurons are involved in working memory. Other studies have shown that mPFC activity shows anticipatory increases in firing rate prior to the execution of a response, suggesting its role in planning imminent actions. The goal ofthe current proposal is to dissociate mPFC involvement in working memory from other functions by comparing the effects of mPFC lesions and the firing patterns of mPFC single neurons between two similar tasks: one that requires working memory and one that does not. Additionally, reversal of these tasks will reveal the role of the mPFC in behavioral flexibility. Finally, we will investigate the interaction between the hippocampus and mPFC by inactivating the hippocampus and concurrently recording mPFC single neurons during task acquisition, performance and reversal. The results will aid in developing a better understanding ofthe role of the mPFC in adaptive behavior, both alone and in conjunction with the hippocampus.