Singer Joshua H, Glowatzki Elisabeth, Moser Tobias, Strowbridge Ben W, Bhandawat Vikas, Sampath Alapakkam P
Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
J Neurosci. 2009 Oct 14;29(41):12802-6. doi: 10.1523/JNEUROSCI.3346-09.2009.
Sensory receptors transduce physical stimuli in the environment into neural signals that are interpreted by the brain. Although considerable attention has been given to how the sensitivity and dynamic range of sensory receptors is established, peripheral synaptic interactions improve the fidelity with which receptor output is transferred to the brain. For instance, synapses in the retina, cochlea, and primary olfactory system use mechanisms that fine-tune the responsiveness of postsynaptic neurons and the dynamics of exocytosis; these permit microcircuit interactions to encode efficiently the output of sensory receptors with the fidelity and dynamic range necessary to extract the salient features of the physical stimuli. The continuous matching of presynaptic and postsynaptic responsiveness highlight how the primary sensory organs have been optimized and can be modulated to resolve sparse sensory signals and to encode the entire range of receptor output.
感觉感受器将环境中的物理刺激转化为神经信号，大脑对这些信号进行解读。尽管人们已经相当关注感觉感受器的灵敏度和动态范围是如何建立的，但外周突触相互作用提高了感受器输出传递到大脑的保真度。例如，视网膜、耳蜗和初级嗅觉系统中的突触利用一些机制来微调突触后神经元的反应性和胞吐作用的动力学；这些机制使微电路相互作用能够以提取物理刺激显著特征所需的保真度和动态范围有效地编码感觉感受器的输出。突触前和突触后反应性的持续匹配突出了初级感觉器官是如何被优化以及如何被调节以解析稀疏的感觉信号并编码感受器输出的整个范围的。
