加拿大麦吉尔大学Adrien Peyrache等研究人员合作揭示皮层网络中兴奋-抑制调谐等效性的局部起源。相关论文于2024年3月15日在线发表于国际学术期刊《自然—神经科学》。

研究人员记录了小鼠后海马下托（PoSub）的神经元群，其中大部分兴奋性神经元是头方向（HD）细胞。研究人员发现，大脑皮层抑制性神经元中最大的一类——快速脉冲（FS）细胞的调谐是宽泛的，而且经常是径向对称的。通过使用傅立叶变换分解调谐曲线，研究人员发现PoSub-FS和PoSub-HD细胞群之间的调谐是等效的。

此外，对丘脑上游细胞群的记录、光遗传学操作和计算建模都提供了证据，表明PoSub-FS细胞的调谐源自局部。这些发现支持了这样一种观点，即兴奋性和抑制性细胞群之间神经元调谐的等效性是局部皮层网络的固有属性。

据悉，兴奋和抑制之间的相互作用决定了大脑皮层表征的保真度。兴奋性神经元的感受野通常会根据编码特征进行精细调谐，但抑制性神经元的调谐原理仍然难以捉摸。

附：英文原文

Title: Local origin of excitatory–inhibitory tuning equivalence in a cortical network

Author: Duszkiewicz, Adrian J., Orhan, Pierre, Skromne Carrasco, Sofia, Brown, Eleanor H., Owczarek, Eliott, Vite, Gilberto R., Wood, Emma R., Peyrache, Adrien

Issue&Volume: 2024-03-15

Abstract: The interplay between excitation and inhibition determines the fidelity of cortical representations. The receptive fields of excitatory neurons are often finely tuned to encoded features, but the principles governing the tuning of inhibitory neurons remain elusive. In this study, we recorded population of neurons in the mouse postsubiculum (PoSub), where the majority of excitatory neurons are head-direction (HD) cells. We show that the tuning of fast-spiking (FS) cells, the largest class of cortical inhibitory neurons, was broad and frequently radially symmetrical. By decomposing tuning curves using the Fourier transform, we identified an equivalence in tuning between PoSub-FS and PoSub-HD cell populations. Furthermore, recordings, optogenetic manipulations of upstream thalamic populations and computational modeling provide evidence that the tuning of PoSub-FS cells has a local origin. These findings support the notion that the equivalence of neuronal tuning between excitatory and inhibitory cell populations is an intrinsic property of local cortical networks.

DOI: 10.1038/s41593-024-01588-5

Source: https://www.nature.com/articles/s41593-024-01588-5