Auditory-cognitive mapping in the frontal cortex during perceptual interference

描述（由申请人提供）：与自然声音环境互动需要学习如何对有行为意义的声音做出反应。额叶皮质（FC）在使我们能够学习声音和动作之间的联系方面起着核心作用。前叶皮层内的神经元与注意力、记忆、任务规则知识、风险和奖励有关。FC神经元的一个关键特征是它们对持续的认知需求的变化具有高度的适应性。在这个项目中，我们的长期目标是了解当听力变得困难时，FC如何改变其声音和行为意义之间关联的神经编码。在拥挤的房间里参与谈话是听力困难的一个常见例子，尤其是当周围的声音相似时。目前尚不清楚这种聆听任务如何影响单个神经元和小群神经元对声音的FC反应。为了探索这个主题，我们开发了一个听觉任务，在这个任务中，动物学习分别通过继续或停止舔水柱来响应声音提示来获得奖励或避免惩罚。当动物执行这些任务时，我们将记录下前皮层的神经反应。我们假设，增加任务声音的相似性会使任务变得更加困难，并且FC对声音的反应会随着相似性而调节。我们的初步结果表明，即使客观任务难度保持不变，FC反应的强度也与动物完成任务的好坏高度相关。因此，我们的研究结果揭示了大脑对声音的反应是如何根据听力困难的主观体验而变化的。在这些问题的另一个转折中，我们将考虑背景噪音如何使听力困难。根据前面的例子，在拥挤的房间里，如果房间里的整体声音水平很高，就很难进行亲密的交谈。据我们所知，背景噪音对听觉任务中FC对声音的反应的影响尚未被研究过。为了探讨这个话题，我们将再次让动物听有行为意义的声音线索，但增加了声学背景噪音来增加任务难度。我们假设前叶皮层的活动会受到噪音水平的调节，这反映了动物在探测声音线索时的不确定性。听力对于健康和听力受损的人来说都是一项挑战。我们的研究将有助于澄清困难听行为中FC生理的基本认识。因此，我们的工作将有助于未来的治疗，旨在使更好的听力在日常环境中。

DESCRIPTION (provided by applicant): Interacting with natural acoustic environments requires learning how to respond to behaviorally meaningful sounds. The frontal cortex (FC) plays a central role in enabling us to learn associations between sounds and actions. Neurons within the FC are involved with attention, memory, knowledge of task rules, risk, and reward. A key feature of FC neurons is that they are highly adaptive in response to changes in ongoing cognitive demands. In this project, our long-term objective is to understand how the FC changes its neural codes for associations between sounds and their behavioral meanings when listening becomes difficult. Participating in a conversation in a crowded room is a common example of difficult listening, especially when neighboring voices are similar. It remains unclear how such listening tasks affect FC responses to sound for single neurons and small populations of neurons. To explore this topic, we developed an auditory task in which animals learn to receive a reward or avoid punishment by, respectively, continuing or stopping to lick a water spout in response to acoustic cues. We shall record neural responses in the FC while the animals perform these tasks. We hypothesize that increasing the similarity of task sounds will make the task more difficult, and that FC responses to the sounds will be modulated with similarity. Our preliminary results suggest that, even when the objective task-difficulty remains unchanged, the strength of FC responses is highly correlated with how well an animal performs the task. Thus, our results shed light on how the brain's response to sound changes according to the subjective experience of listening difficulty. In another twist on these questions, we shall consider how background noise makes listening difficult. Drawing from the previous example, having an intimate conversation in a crowded room will be difficult if the overall level of voices in the roo is high. To the best of our knowledge, the effect of background noise on FC responses to sounds during an auditory task has not been studied. To explore this topic, we will again have animals listen for behaviorally meaningful acoustic cues, but with the addition of acoustic background noise to increase task difficulty. We hypothesize that FC activity will be modulated by the level of noise, reflecting the animals' uncertainty in detecting the acoustic cues. Listenig can be challenging for healthy and hearing impaired people. Our studies will help clarify the basic understanding of FC physiology during difficult listening behaviors. As a result, our work will contribute to future therapies designed to enable better hearing in every-day settings.