Fischer Linda, Leibold Christian, Felmy Felix
Zoologisches Institut, Stiftung Tierärztliche Hochschule Hannover, Hannover, Germany.
Department Biologie II, Ludwig-Maximilians-Universität München, Munich, Germany.
Front Cell Neurosci. 2018 Jan 24;12:8. doi: 10.3389/fncel.2018.00008. eCollection 2018.
Auditory signals carry relevant information on a large range of time scales from below milliseconds to several seconds. Different stages in the auditory brainstem are specialized to extract information in specific frequency domains. One biophysical mechanism to facilitate frequency specific processing are membrane potential resonances. Here, we provide data from three different brainstem nuclei that all exhibit high-frequency subthreshold membrane resonances that are all most likely based on low-threshold potassium currents. Fitting a linear model, we argue that, as long as neurons possess active subthreshold channels, the main determinant for their resonance behavior is the steady state membrane time constant. Tuning this leak conductance can shift membrane resonance frequencies over more than a magnitude and therefore provide a flexible mechanism to tune frequency-specific auditory processing.
听觉信号在从毫秒以下到几秒的大范围时间尺度上携带相关信息。听觉脑干的不同阶段专门用于在特定频率域中提取信息。促进频率特异性处理的一种生物物理机制是膜电位共振。在这里，我们提供了来自三个不同脑干核的数据，它们都表现出高频阈下膜共振，这些共振很可能都基于低阈值钾电流。通过拟合线性模型，我们认为，只要神经元拥有活跃的阈下通道，其共振行为的主要决定因素就是稳态膜时间常数。调节这种泄漏电导可以使膜共振频率改变超过一个数量级，因此提供了一种灵活的机制来调节频率特异性听觉处理。
