Investigating Auditory-Motor Interactions During Rhythm Perception in a Small Animal Model

摘要 世界上许多音乐都有周期性的节奏，事件在时间上有规律地重复，人们随着节奏鼓掌， 动起来，唱起来。检测和预测周期性听觉节律的能力是 以音乐为基础的治疗各种神经疾病，包括改善语音处理 阅读障碍，增强中风后的语言恢复，并使帕金森病的步态正常化。然而，神经 节奏感知的潜在机制还没有被很好地理解，并且由于缺乏一种 动物模型，允许在节律感知过程中精确测量和操纵神经回路。 人类神经成像研究表明，感知周期性音乐节奏会强烈地刺激运动 计划系统，包括运动前皮质和基底神经节，即使在听者没有移动或准备的情况下 去搬家。在这里，我们测试了运动规划系统积极参与学习识别的假设 时间周期性，并将关于周期性事件的时间的预测传达给听觉系统。 我们建议利用在发声学习中所描述的听觉-运动神经回路 利用动物模型中可能的机械学研究来测试这些想法。像人类一样(与非人类不同 人类灵长类)，发声学习鸟类在运动计划区域和听觉之间有很强的联系 由于它们依赖于复杂的、学习过的声音序列进行交流，这些区域。中的听觉-运动电路 鸣禽和人类在结构和功能上有许多相似之处。最近，我们展示了鸣禽可以 很容易学会识别基本的周期模式(等时，或事件之间的相等时间)，并能够 在大范围的Tempi中检测这种模式。在目标1中，我们将测试来自前置电机的神经信号 在这种灵活识别周期节律的能力中，区域起着因果作用。在目标2中，通过在听觉中记录 当可逆地沉默相互连接的运动前区域的活动时，我们将测试 运动前信号影响对周期节律的听觉处理。在目标3中，通过记录前置电机的活动 随着鸟类学习将等时识别为一种全球时间模式，我们将决定运动前 神经元对时间规律性发展敏感，并表现出预测即将到来的事件的时间的活动。 建立节奏感知的动物模型将对音乐神经科学产生革命性的影响，允许 详细研究节律感知和节律信息传递的神经机制 音乐干预，以增强正常和疾病状态下的功能。

ABSTRACT Much of the world’s music has periodic rhythms with events repeating regularly in time, to which people clap, move, and sing. The ability to detect and predict periodic auditory rhythms is central to the positive effects of music-based therapies on a variety of neurological disorders, including improving phonological processing in dyslexia, enhancing language recovery after stroke, and normalizing gait in Parkinson’s disease. Yet the neural mechanisms underlying rhythm perception are not well understood, and progress is impeded by the lack of an animal model that allows precise measurement and manipulation of neural circuits during rhythm perception. Human neuroimaging studies indicate that perceiving periodic musical rhythms strongly engages the motor planning system, including premotor cortex and basal ganglia, even when the listener is not moving or preparing to move. Here, we test the hypothesis that the motor planning system is actively involved in learning to recognize temporal periodicity and communicates predictions about the timing of periodic events to the auditory system. We propose to take advantage of the well-described auditory-motor circuits in vocal learning songbirds and leverage the mechanistic studies possible in an animal model to test these ideas. Like humans (and unlike non- human primates), vocal learning birds have strong connections between motor planning regions and auditory regions due to their reliance on complex, learned vocal sequences for communication. Auditory-motor circuits in songbirds and humans have many structural and functional parallels. Recently, we showed that songbirds can readily learn to recognize a fundamental periodic pattern (isochrony, or equal timing between events) and can detect this pattern across a broad range of tempi. In Aim 1, we will test whether neural signals from premotor regions play a causal role in this ability to flexibly recognize periodic rhythms. In Aim 2, by recording in auditory cortex while reversibly silencing activity in a reciprocally connected premotor region, we will test whether premotor signals influence auditory processing of periodic rhythms. In Aim 3, by recording activity in a premotor region as birds learn to recognize isochrony as a global temporal pattern, we will determine whether premotor neurons develop sensitivity to temporal regularity and exhibit activity that predicts the timing of upcoming events. Establishing an animal model for rhythm perception will be transformative for music neuroscience, allowing detailed investigation of the neural mechanisms underlying rhythm perception and informing rhythm-based musical interventions to enhance function in normal and disease states.