Fuchs Paul Albert
The Cochlear Neurotransmission Laboratory, Center for Hearing and Balance, Department of Otolaryngology--Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21286, USA.
J Physiol. 2005 Jul 1;566(Pt 1):7-12. doi: 10.1113/jphysiol.2004.082214. Epub 2005 Apr 21.
The activity of individual afferent neurones in the mammalian cochlea can be driven by neurotransmitter released from a single synaptic ribbon in a single inner hair cell. Thus, a ribbon synapse must be able to transmit all the information on sound frequency, intensity and timing carried centrally. This task is made still more demanding by the process of binaural sound localization that utilizes separate computations of time and intensity, with temporal resolution as fine as 10 micros in central nuclei. These computations may rely in part on the fact that the response phase (at the characteristic frequency) of individual afferent neurones is invariant with intensity. Somehow, the ribbon synapse can provide stronger synaptic drive to signal varying intensity, without accompanying changes in transmission time that ordinarily occur during chemical neurotransmission. Recent ultrastructural and functional studies suggest features of the ribbon that may underlie these capabilities.
哺乳动物耳蜗中单个传入神经元的活动可由单个内毛细胞中单个突触带释放的神经递质驱动。因此，一个带状突触必须能够传递所有关于声音频率、强度和时间的信息并向中枢传递。利用时间和强度的单独计算进行双耳声音定位的过程，使这项任务的要求更高，在中枢核中时间分辨率可达10微秒。这些计算可能部分依赖于这样一个事实，即单个传入神经元的反应相位（在特征频率处）不随强度而变化。不知何故，带状突触可以提供更强的突触驱动来传递变化的强度信号，而不会伴随化学神经传递过程中通常发生的传输时间变化。最近的超微结构和功能研究揭示了带状突触可能具备这些能力的特征。
