Comparison of midbrain and thalamic space-specific neurons in barn owls.
Comparison of midbrain and thalamic space-specific neurons in barn owls.
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仓鸮中脑和丘脑空间特异性神经元的比较。
DOI：
10.1152/jn.00833.2005
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发表时间：
2006
影响因子：
2.5
通讯作者：
Peña,JoséLuis
中科院分区：
文献类型：
--
作者：
Pérez,MaríaLucía;Peña,JoséLuis
仓鸮听觉通路中神经元的空间感受野是对耳间时间（ITD）和刺激频率上的电平差异组合敏感的结果。猫头鹰的前脑和顶盖都含有这种神经元。在听觉空间的中脑地图合成之前，导致前脑和顶盖表示听觉空间的神经通路分离。第一个核团，专门属于前脑或顶盖通路的卵圆核（Ov）和下丘的外部核（ICx），分别。两者都接受来自下丘外侧壳分部的突起，但不相互连接。以往的研究表明，猫头鹰的听觉空间的顶盖表示是不同的猫头鹰的前脑和哺乳动物的大脑。我们解决的问题，是否在这两个途径的空间线索的计算是相同的，通过比较的ITD调谐的Ov和ICx神经元。与ICx不同，频率和ITD调谐之间的关系尚未在单个OV单元中进行研究。与ICx空间特异性神经元的显著频率独立ITD调谐相反，ITD选择性随Ov频率而变化。我们还观察到，Ov的空间调谐神经元响应较低的频率，更广泛地调谐到ITD比在ICx。因此，在两个声音定位途径中，频率和ITD的整合存在差异。丘脑神经元不仅在更宽的频带内整合空间信息，而且还跨ITD通道整合空间信息。
Spatial receptive fields of neurons in the auditory pathway of the barn owl result from the sensitivity to combinations of interaural time (ITD) and level differences across stimulus frequency. Both the forebrain and tectum of the owl contain such neurons. The neural pathways, which lead to the forebrain and tectal representations of auditory space, separate before the midbrain map of auditory space is synthesized. The first nuclei that belong exclusively to either the forebrain or the tectal pathways are the nucleus ovoidalis (Ov) and the external nucleus of the inferior colliculus (ICx), respectively. Both receive projections from the lateral shell subdivision of the inferior colliculus but are not interconnected. Previous studies indicate that the owl's tectal representation of auditory space is different from those found in the owl's forebrain and the mammalian brain. We addressed the question of whether the computation of spatial cues in both pathways is the same by comparing the ITD tuning of Ov and ICx neurons. Unlike in ICx, the relationship between frequency and ITD tuning had not been studied in single Ov units. In contrast to the conspicuous frequency independent ITD tuning of space-specific neurons of ICx, ITD selectivity varied with frequency in Ov. We also observed that the spatially tuned neurons of Ov respond to lower frequencies and are more broadly tuned to ITD than in ICx. Thus there are differences in the integration of frequency and ITD in the two sound-localization pathways. Thalamic neurons integrate spatial information not only within a broader frequency band but also across ITD channels.