A comparison of neuron response properties in areas A1 and CM of the marmoset monkey auditory cortex: Tones and broadband noise
A comparison of neuron response properties in areas A1 and CM of the marmoset monkey auditory cortex: Tones and broadband noise
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DOI：
10.1152/jn.00248.2004
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发表时间：
2005-01-01
影响因子：
2.5
通讯作者：
Hackett, TA
中科院分区：
文献类型：
--
作者：
Kajikawa, Y;de La Mothe, L;Hackett, TA
本研究的目的是比较绒猴听觉皮质两个相邻区域的反应特性。在氯胺酮麻醉动物的核心区A1和尾内侧带区CM记录了对50 ms音调和宽带噪声爆发（BBN）的多单位反应。在A1和CM的神经元表现出强大的低阈值短潜伏期响应BBN和音调，而相邻的侧带区的神经元反应不良或无反应的音调和噪音。除了在CM的人口广泛调谐的单位，特征频率（CF）可以确定为所有记录网站在A1和CM。这两个地区都是tonotopically组织和共享一个高CF边界。而在A1的tonotopic梯度是平滑和连续的整个领域，在CM的梯度是不连续的，和中间CF范围是代表性不足。对于BBN刺激，率水平函数在很大程度上是单调的A1和CM。两个地区的反应情况也相似。作为一个群体，CM中的神经元与A1的区别在于在较高强度下显著更短的响应潜伏期、更低的阈值和更宽的调谐带宽。结果表明，虽然A1和CM代表解剖学和生理学上不同的区域，但与侧带区域相比，它们在麻醉下的反应曲线有相当大的重叠。因此，可能需要改进灵长类动物听觉皮层的当前模型，以解释听觉带区域之间的组织差异。
The purpose of this study was to compare response properties of two adjacent areas of the marmoset monkey auditory cortex. Multiunit responses to 50 ms tones and broadband noise bursts (BBN) were recorded in the core area, A1, and the caudomedial belt area, CM, of ketamine-anesthetized animals. Neurons in A1 and CM exhibited robust low-threshold short-latency responses to BBN and tones, whereas neurons in adjoining lateral belt areas were poorly responsive or unresponsive to tones and noise. Except for a population of broadly tuned units in CM, the characteristic frequency (CF) could be determined for all recording sites in A1 and CM. Both areas were tonotopically organized and shared a high CF border. Whereas the tonotopic gradient in A1 was smooth and continuous across the field, the gradient in CM was discontinuous, and the intermediate CF range was underrepresented. For BBN stimuli, rate level functions were largely monotonic in A1 and CM. Response profiles were also similar in both areas. As a population, neurons in CM were distinguished from A1 by significantly shorter response latencies, lower thresholds, and broader tuning bandwidth at higher intensities. The results indicated that, while A1 and CM represent anatomically and physiologically distinct areas, their response profiles under anesthesia overlapped considerably compared with the lateral belt areas. Therefore refinements of current models of the primate auditory cortex may be needed to account for differences in organization among the auditory belt areas.