Neural coding of categorical auditory perception

刺激连续体的分类是几种感觉模态的基本过程。范畴感知涉及到类别标注和区分两个方面，在人类的行为层面上得到了广泛的研究，特别是在言语感知方面。本研究拟建立小鼠模型，研究听觉系统中分类知觉的神经编码。有幼鼠经历的成年小鼠在中心频率接近50 kHz时，会将窄带宽（小于22.5 kHz）的超声噪声信号视为幼鼠的隔离叫声，从而促使它们寻找和找回丢失的幼鼠。另一方面，没有幼崽经历的成年老鼠不能明确地感知超声波。分类知觉的神经关联将通过对有幼崽经历的小鼠的听觉皮层进行急性电生理实验来研究。目的1建立了幼犬的自然叫声是如何在不同的听觉皮层子场中编码的，以及哪些子场最适合自然叫声的特征。目的2寻找分类感知作为带宽函数的可能神经关联，目的3将通过对比有幼崽经历的小鼠和没有幼崽经历的小鼠的神经编码来证实这一点。通过完成这些初步研究，将为未来使用遗传方法研究分类知觉形成的神经内分泌和神经调节机制奠定基础。

The division of a continuum of stimuli into categories is a fundamental process in several sensory modalities. Categorical perception, which involves both category labeling and discrimination, has been researched extensively at the behavioral level in humans, especially in the context of speech perception. The research proposed here would develop a mouse model to study the neural coding of a categorical percept in the auditory system. Adult mice experienced with pups categorically perceive narrow bandwidth (less than 22.5 kHz) ultrasound noise signals near a 50 kHz center frequency as pup isolation calls, prompting a search and retrieval for lost mouse pups. On the other hand, adult mice that do not have experience with pups do not categorically perceive ultrasounds. The neural correlate of the categorical percept will be studied by performing acute electrophysiology experiments in the auditory cortex of mice that have experience with pups. Aim 1 establishes how natural pup calls are coded in the different auditory cortical subfields, and which subfields are best adapted to the characteristics of natural calls. Aim 2 searches for a possible neural correlate of the categorical perception as a function of bandwidth, and Aim 3 would confirm this by contrasting the neural coding in mice experienced with pups to those who are not. By completing these initial studies, a foundation will be laid for future work into the neuroendocrine and Lneuromodulato mechanisms underlying the formation of the categorical percept using genetic methods.