Frequency organization of delay-sensitive neurons in the auditory cortex of the FM bat, Myotis lucifugus.
Frequency organization of delay-sensitive neurons in the auditory cortex of the FM bat, Myotis lucifugus.
复制标题
FM 蝙蝠（Myotis lucifugus）听觉皮层延迟敏感神经元的频率组织。
DOI：
10.1152/jn.1994.72.1.366
复制
发表时间：
1994
影响因子：
2.5
通讯作者：
Wong,D
中科院分区：
文献类型：
--
作者：
Paschal,WG;Wong,D
1.小棕色蝙蝠，鼠耳蝠lucifugus，采用生物声纳脉冲包含宽带调频（FM）的声音只有一个谐波在初始阶段的回声定位。整个听觉皮层的神经元表现出延迟依赖的促进人工脉冲和回声在特定的回声延迟。这些延迟敏感神经元的细胞外单位记录确定了声音对中的基本频率分量及其引起最大便利化的相对时间。2.模拟脉冲和回波的整个60 kHz扫描被分为四个相等的频谱四分之一（Ist，IInd，IIIrd和IVth），每个线性扫描15 kHz向下1 ms，以确定最大促进所必需的频谱部分。最大的促进同样引起的脉冲回波对，其中的声音成分包括整个60 kHz的FM扫描或只有必要的季度。大多数神经元需要第四个四分之一的脉冲和回声的延迟敏感性。这是一致的假设，基本季度扫兴奋频率略高于抑制频率。3.光谱和时间的延迟灵敏度的贡献进行了独立的检查。每个频谱四分之一的回声的频谱内容是不同的回声延迟，和声音对响应进行了比较。最大的促进在个别延迟敏感的神经元需要一个特定的部分回波频谱和一个特定的回波延迟。4.基本脉冲和回波象限的FM扫描进一步缩窄到它们的最小带宽，并且确定基本脉冲频率（EPF）和基本回波频率（EEF）。EPF和EEF在FM带宽中的平均值约为8 kHz，代表了该FM蝙蝠发射的回声定位脉冲的不同频谱部分。所有神经元表现出延迟敏感性搜索刺激，其中脉冲回波刺激包括15 kHz FM对。5.延迟敏感性几乎所有的神经元需要脉冲和回声成分的基本频率不同。然而，在这些神经元中，39%的脉冲和回声之间存在一些频谱重叠。大多数神经元（81%）需要脉冲和回声，其中它们的平均频率相差>或= 16 kHz。这包括脉冲和回声在频谱上重叠的神经元，以及声音分量没有重叠但被相对较小的频率范围分开的神经元。6.单个神经元的易化频率调谐曲线与其基本脉冲和回声频率进行了测量。（400字处截断摘要）
1. The little brown bat, Myotis lucifugus, employs biosonar pulses containing broadband frequency -modulated (FM) sounds of only one harmonic during the initial phases of echolocation. Neurons throughout the auditory cortex exhibit delay-dependent facilitation to artificial pulses and echoes at particular echo delays. Extracellular unit recordings of these delay-sensitive neurons determined the essential frequency components in the sound pair and their relative timing for evoking maximum facilitation. 2. The entire 60-kHz sweep of both the simulated pulse and echo were divided into four equal spectral quarters (Ist, IInd, IIIrd, and IVth), each linearly sweeping 15 kHz downward in 1 ms, to determine the spectral parts essential for maximal facilitation. Maximal facilitation was evoked equally by pulse-echo pairs in which the sound components consisted of either the entire 60-kHz FM sweeps or only the essential quarters. Most neurons required the IVth quarter of the pulse and the echo for delay sensitivity. This is consistent with the hypothesis that the essential quarters swept excitatory frequencies just above inhibitory frequencies. 3. The spectral and temporal contributions to delay sensitivity were examined independently. The spectral content for each spectral quarter of echo was varied in echo delay, and the sound-pair responses were compared. Maximal facilitation in individual delay-sensitive neurons required both a specific part of the echo spectrum and a specific echo delay. 4. The FM sweeps of the essential pulse and echo quarters were further narrowed to their minimum bandwidth, and the essential pulse frequencies (EPFs) and essential echo frequencies (EEFs) were determined. Both the EPFs and EEFs averaged approximately 8 kHz in FM bandwidth and represented different spectral parts of the echolocation pulse emitted by this FM bat. All neurons showed delay sensitivity to search stimuli in which pulse-echo stimuli consisted of 15-kHz FM pairs. 5. Delay sensitivity in virtually all neurons required pulse and echo components whose essential frequencies differed. However, some spectral overlap was found between the pulse and echo in 39% of these neurons. The majority of neurons (81%) required a pulse and echo in which their mean frequencies differed by>or = 16 kHz. This includes neurons with pulse and echo overlapping spectrally and those with sound components showing no overlap but separated by a relatively small frequency range. 6. The facilitative frequency-tuning curves of individual neurons were measured with their essential pulse and echo frequencies.(ABSTRACT TRUNCATED AT 400 WORDS)