Schoppa Nathan E, Westbrook Gary L
Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97201, USA.
Nat Neurosci. 2002 Nov;5(11):1194-202. doi: 10.1038/nn953.
Information processing in the brain may rely on temporal correlations in spike activity between neurons. Within the olfactory bulb, correlated spiking in output mitral cells could affect the odor code by either binding or amplifying signals from individual odorant receptors. We examined the timing of spike trains in mitral cells of rat olfactory bulb slices. Depolarization of mitral cell pairs elicited spikes that were correlated on a rapid timescale (< or =10 ms) for cells whose primary dendrites projected to the same glomerulus. Correlated spiking was driven by a novel mechanism that depended on electrical coupling at mitral cell primary dendrites; the specific synchronizing signal was a coupled depolarization ( approximately 20 ms) that was mediated by dendritic AMPA autoreceptors. We suggest that glomerulus-specific correlated spiking in mitral cells helps to preserve the fidelity of odor signals that are delivered to the olfactory cortex.
大脑中的信息处理可能依赖于神经元之间尖峰活动的时间相关性。在嗅球内，输出型二尖瓣细胞中的相关尖峰活动可能通过结合或放大来自单个气味受体的信号来影响气味编码。我们研究了大鼠嗅球切片中二尖瓣细胞尖峰序列的时间。对于其主要树突投射到同一肾小球的细胞，二尖瓣细胞对的去极化引发了在快速时间尺度（≤10毫秒）上相关的尖峰。相关的尖峰活动由一种新机制驱动，该机制依赖于二尖瓣细胞主要树突处的电耦合；特定的同步信号是由树突AMPA自身受体介导的耦合去极化（约20毫秒）。我们认为，二尖瓣细胞中肾小球特异性的相关尖峰活动有助于保持传递到嗅觉皮层的气味信号的保真度。
