The Role of Tonic Neural Responses in Auditory Pitch Perception in Awake Rat A1

描述（由申请人提供）：细粒度听觉音高感知的缺陷与语言学习障碍、某些形式的阅读障碍和更严重的神经系统疾病有关。细粒度的频率辨别被认为是初级听觉皮层（A1）的功能，但负责的机制仍然不清楚。在个体A1神经对等频音调的反应的时间过程中，相对非频率选择性的相位性兴奋让位于在音调的整个持续时间内持续的更窄选择性的强直性兴奋。A1中的紧张性反应可能编码细粒度的光谱感知。本研究将探讨的作用和功能的紧张性反应方面的纯音在清醒的大鼠使用的组合，神经记录，微刺激，和行为技术的音高感知。来自多通道电极阵列的神经记录将用于充分表征A1对等频音调的紧张性神经反应。一个同时的神经记录和微刺激范例将被用来检查皮层内调制等频率刺激处理的贡献。最后，微刺激将与行为范例配对，以研究人工激活A1以模仿自然等频响应的模式引起的感知音高。这些技术的结合将提供一个独特的详细的机制和功能的紧张性反应在A1方面的细粒度的音高感知。这项研究将有助于了解大脑如何将声音信息分解为声音频率。从这项研究中获得的知识可能有助于开发更好的治疗儿童语言学习障碍或中风和其他脑损伤引起的语言障碍的方法。

DESCRIPTION (provided by applicant): Deficits in fine-grained auditory pitch perception have been implicated in language learning disorders, certain forms of dyslexia, and more severe neurological conditions. Fine-grained frequency discrimination is believed to be a function of the primary auditory cortex (A1), but the mechanism responsible is still unclear. In the time-course of individual A1 neural responses to iso-frequency tones, relatively non-frequency- selective phasic excitation gives way to more narrowly selective tonic excitation that is sustained throughout the duration of the tone. Tonic responses in A1 may code for fine-grained spectral perception. This study will investigate the role and functionality of tonic responses with respect to pitch perception of pure tones in awake rats using a combination of neural recording, microstimulation, and behavioral techniques. Neural recordings from multichannel electrode arrays will be used to fully characterize tonic neural responses in A1 to iso-frequency tones. A simultaneous neural recording and microstimulation paradigm will be used to examine the contribution of intracortical modulation to processing of iso-frequency stimuli. Finally, microstimulation will be paired with a behavioral paradigm to investigate the perceived pitch of sensation elicited by artificial activation of A1 in a pattern mimicking natural iso-frequency responses. The combination of these techniques will provide a uniquely detailed view of the mechanisms and functionality of tonic responses in A1 with respect to fine-grained pitch perception. This study will help in understanding how the brain breaks down sound information into sound frequency. The knowledge gained from this study could be useful in developing better treatments for childhood language learning disorders or for language disorders stemming from strokes and other brain damage.