REVERSIBLE DISRUPTION OF MEMORY

上一个支持期的工作发现， 在延迟期间刺激猴子的内侧颞叶 一段时间的延迟匹配样本的任务是高度破坏性的， 如果只有少数图像被重复使用，则性能很差。相同的 如果使用新鲜图像， 每一次审判在人类受试者的记忆任务中，重复使用 图像导致在延迟期间主动排练的策略。 在猴子身上，重复图像的使用是诱导如此- 称为延迟活动。这是神经元放电率的提高 通常持续整个延迟期， 对不同的刺激有选择性地活跃。因此，整个活动 一群神经元编码了一种记忆， 想起来延迟活动看起来像是神经元版本的 连续排练，是一个很好的候选人的神经 在这些条件下的延迟期间存储器的实施例。的 这种延迟活动的魅力在于它可能是我们最好的模型 对于日常人类工作记忆来说， 想的延迟活动是记忆的保持器的证据 是间接的。目前提案的目的是测试 这个假设直接。这将通过使用电气 已知干扰延迟活动刺激（参见 初步研究）。如果神经元的延迟活动是 那么，延迟活动的中断应该会中断 行为记忆该项目的贡献直接针对 一种重要的记忆神经机制其临床 相关性不是直接的，但可能是深刻的，因为 对记忆回路的充分理解应该会对 随着人口老龄化， 与记忆有关的问题。

Work in the previous support period led to a finding that electrical stimulation of the medial temporal lobe of monkeys during the delay period of a delayed matching-to-sample task was highly disruptive of performance if only a few images were repeatedly reused. The identical stimulation was only mildly disruptive if fresh images were used for each trial. In memory tasks with human subject, the use of repeated images leads to a strategy of active rehearsal during the delay period. In monkeys, the use of repeated images is a key to inducing the so- called delay activity. This is an elevated discharge rate in neurons usually lasting throughout the delay period, with different neurons selectively active for different stimuli. Thus, the activity across the population of neurons encodes a memory of that which is to-be- remembered. The delay activity appears like a neuronal version of continuous rehearsal, and is an excellent candidate for the neural embodiment of memory during the delay under these conditions. The fascination with this delay activity is that it may be our best model for the everyday human working memory which is the substrate for thought. The evidence that delay activity is the holder of the memory is, however, indirect. The purpose of the current proposal is to test that hypothesis directly. This will be done by using electrical stimulation which is known to disrupt that delay activity (see Preliminary Studies). If delay activity of neurons is the carrier of the memory then disruption of the delay activity should disrupt the behavioral memory. The contribution of this project is aimed directly at a prominent candidate neuronal mechanism of memory. Its clinical relevance is not immediate but could nonetheless be profound since a full understanding of the mnemonic circuitry should have a major impact on the important - and with the aging population - growing health problems involving memory.