Investigating the contributions of neural competition to intentional forgetting and real-time neurofeedback

遗忘是一种适应性过程，在保持记忆效率方面起着关键作用 操作，并可以主动抑制不受欢迎的(例如，不愉快或无关的信息)来自我们的记忆 意识。在编码期间故意忘记不想要的记忆可以通过 前额叶控制区，通过直接抑制海马体编码过程，或通过参与海马体 检索过程，以用替换来替换不需要的存储器。其背后的神经机制 然而，刻意遗忘并没有被很好地理解--这项研究项目的目标是描述如何 记忆表征的神经竞争依赖学习--一种神经机制 被证明有助于附带遗忘--解释了故意遗忘。我们还建议使用实时 神经反馈(在一个人执行任务时提供有关其大脑活动的信息 核磁共振扫描仪)选择性地改善或损害随后的记忆。 最近的一项理论为遗忘背后的机制提供了令人信服的解释。联席- 在对物品进行编码和提取的过程中，激活多个思维会导致 这些想法反过来又不利于随后对某一项目的记忆。这一发现是 与计算学习模型所产生的“非单调可塑性假说”一致。在……里面 以下建议，研究一检验记忆编码过程中的非单调可塑性原理 也延伸到动机遗忘。我们建议管理一个项目-方法有意遗忘任务在 哪些参与者将被要求根据提示记住或忘记项目 项目的演示。我们假设“要被记住”和“要被记住”之间的神经竞争 忘记的项将导致随后忘记项的表示形式，该项表示将丢失 竞争。我们将使用fMRI数据的多变量模式分类来量化水平(即低、中或 Strong)激活“要忘记”和“要记住”项，以便解码或跟踪 每项试验中这些项目的相对强度。这第一项研究的结果也使我们能够测试 颞叶腹侧皮质神经竞争量与对照连接性的关系 前额叶皮质的区域到海马体的细分，以及随后的遗忘行为。 此外，在研究2中，我们打算使用神经反馈训练来校准神经竞争的数量 在内存编码过程中引发。我们将在闭环中对编码策略进行行为修改 神经反馈系统，以改善或干扰(即诱导遗忘)后续记忆 性能。

Forgetting is an adaptive process that plays a critical role in sustaining the efficiency of mnemonic operations and can actively inhibit unwelcome (e.g. unpleasant or irrelevant information) memories from our awareness. The intentional forgetting of unwanted memories during encoding can be accomplished, via prefrontal control regions, by directly inhibiting hippocampal encoding processes, or by engaging hippocampal retrieval processes to replace the unwanted memory with substitutes. The neural mechanisms that underlie intentional forgetting, however, is not well understood -- the goal of this research project is to characterize how competition dependent learning via neural competition of memory representations – a neural mechanism shown to contribute to incidental forgetting – explains intentional forgetting. We also propose using real-time neurofeedback (providing information about a person's brain activity while they are performing tasks inside an MRI scanner) to either selectively improve or impair subsequent remembering. One recent theory provides a compelling explanation for a mechanism underlying forgetting. The co- activation of multiple thoughts during encoding and retrieval of an item can lead to neural competition between these thoughts, which in turn, are detrimental to the subsequent remembering of an item. This finding is consistent with the `non-monotonic plasticity hypothesis' generated by computational models of learning. In the following proposal, Study 1 tests whether the principle of non-monotonic plasticity during memory encoding also extends to motivated forgetting. We propose to administer an item-method intentional forgetting task in which participants will be required to either remember or forget items dependent on a cue following the presentation of the item. We hypothesize that neural competition between `to be remembered' and `to be forgotten' items will contribute to the subsequent forgetting of the item representation that `loses' the competition. We will use multivariate pattern classification of fMRI data to quantify the level (i.e. low, medium or strong) of activation for the `to be forgotten and `to be remembered' items in order to decode or track the relative strength of these items across each trial. The findings of this first study also allow us to test the relationship between the amount of neural competition in ventral temporal cortex, the connectivity from control regions in the prefrontal cortex to subdivisions of the hippocampus, and subsequent forgetting behavior. Furthermore, in Study 2, we intend to use neurofeedback training to calibrate the amount of neural competition elicited during memory encoding. We will behaviorally modify encoding strategies in a closed-loop neurofeedback system in order to improve on or interfere with (i.e. induce forgetting) subsequent memory performance.