Recanzone G H
Center for Neuroscience and Section of Neurobiology, Physiology and Behavior, University of California at Davis, 1544 Newton Ct., Davis, CA 95616, USA.
Hear Res. 2000 Dec;150(1-2):104-18. doi: 10.1016/s0378-5955(00)00194-5.
The primate auditory cortex is anatomically divided into several areas, but little is known about the functional differences between these areas. Similarly, although neurons in sub-cortical auditory areas of other species have been classified into distinct categories, these criteria have not been applied in primates. This study measured the responses of single neurons in the primary auditory cortex (AI) and the caudomedial field (CM) to tones and noise. Most neurons could be qualitatively classified as onset, sustained, or sustained-onset, but never as primary (VIII nerve)-like or chopper. Quantitative analysis showed a continuum of response types, from having only onset responses to responding throughout the stimulus period. AI neurons had higher firing rates that CM neurons, but CM neurons had higher firing rates to noise stimuli compared to tone stimuli, and a greater percentage of CM neurons had excitatory responses after stimulus offset. There were no differences in the percentage of neurons that had tonic or inhibitory responses. These results indicate that the responses of neurons in the primate auditory cortex are better described as a continuum rather than as discrete classes, and provide further evidence that auditory information is processed in series between AI and CM in the primate.
灵长类动物的听觉皮层在解剖学上可分为几个区域，但对这些区域之间的功能差异了解甚少。同样，尽管其他物种皮层下听觉区域的神经元已被分类为不同类别，但这些标准尚未应用于灵长类动物。本研究测量了初级听觉皮层（AI）和尾内侧区（CM）单个神经元对纯音和噪声的反应。大多数神经元在性质上可分为起始型、持续型或持续起始型，但从未被分类为初级（第八神经）样或斩波型。定量分析显示了从仅具有起始反应到在整个刺激期都有反应的连续反应类型。AI神经元的放电率高于CM神经元，但与纯音刺激相比，CM神经元对噪声刺激的放电率更高，并且在刺激结束后有更大比例的CM神经元具有兴奋性反应。具有紧张性或抑制性反应的神经元百分比没有差异。这些结果表明，灵长类动物听觉皮层中神经元的反应更好地被描述为一个连续体，而不是离散的类别，并进一步证明在灵长类动物中，听觉信息在AI和CM之间是串行处理的。
