How the owl resolves auditory coding ambiguity.
How the owl resolves auditory coding ambiguity.
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猫头鹰如何解决听觉编码歧义。
DOI：
10.1073/pnas.95.18.10932
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发表时间：
1998
影响因子：
11.1
通讯作者：
Mazer,JA
中科院分区：
文献类型：
--
作者：
Mazer,JA
仓鸮（Tyto alba）使用耳间时差（ITD）线索将声音定位在水平面上。具有尖锐频率调谐的低阶双耳听觉神经元充当窄带重合检测器;这些神经元对具有特定ITD及其相位等效物的声音的响应同样良好，并且被称为相位模糊。具有宽频率调谐的高阶神经元对单个ITD响应宽带声音具有明确的选择性，并且对相位等效物几乎没有响应。单个ITD的选择性被认为是源于耳蜗中的并行窄带频率通道的会聚。ITD调谐到可变带宽的刺激测量猫头鹰的下丘高阶神经元检查的规则，管理频率通道收敛和相位模糊的分辨率之间的关系。模糊度随着刺激带宽的增加而降低，在2-3 kHz时达到最小值。两个独立的机制似乎有助于消除歧义：一个抑制和一个促进。信息的整合所进行的并行，分布式处理渠道是一个共同的主题感觉处理，跨越模态和物种的界限。猫头鹰的相位模糊和频率通道收敛的解决方案的基本原则可能会影响其他感官系统，如电定位在电鱼和计算的鸟类和哺乳动物的视觉系统中的双眼视差。
The barn owl (Tyto alba) uses interaural time difference (ITD) cues to localize sounds in the horizontal plane. Low-order binaural auditory neurons with sharp frequency tuning act as narrow-band coincidence detectors; such neurons respond equally well to sounds with a particular ITD and its phase equivalents and are said to be phase ambiguous. Higher-order neurons with broad frequency tuning are unambiguously selective for single ITDs in response to broad-band sounds and show little or no response to phase equivalents. Selectivity for single ITDs is thought to arise from the convergence of parallel, narrow-band frequency channels that originate in the cochlea. ITD tuning to variable bandwidth stimuli was measured in higher-order neurons of the owl’s inferior colliculus to examine the rules that govern the relationship between frequency channel convergence and the resolution of phase ambiguity. Ambiguity decreased as stimulus bandwidth increased, reaching a minimum at 2–3 kHz. Two independent mechanisms appear to contribute to the elimination of ambiguity: one suppressive and one facilitative. The integration of information carried by parallel, distributed processing channels is a common theme of sensory processing that spans both modality and species boundaries. The principles underlying the resolution of phase ambiguity and frequency channel convergence in the owl may have implications for other sensory systems, such as electrolocation in electric fish and the computation of binocular disparity in the avian and mammalian visual systems.