University Medical Center of the Johannes Gutenberg University Mainz, Institute of Pathophysiology, 55128 Mainz, Germany.
Focus Program Translational Neurosciences, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany.
Int J Mol Sci. 2019 May 27;20(10):2604. doi: 10.3390/ijms20102604.
In contrast to the long-standing notion that the role of individual neurons in population activity is vanishingly small, recent studies have shown that electrical activation of only a single cortical neuron can have measurable effects on global brain state, movement, and perception. Although highly important for understanding how neuronal activity in cortex is orchestrated, the cellular and network mechanisms underlying this phenomenon are unresolved. Here, we first briefly review the current state of knowledge regarding the phenomenon of single-cell induced network modulation and discuss possible underpinnings. Secondly, we show proof of principle for an experimental approach to elucidate the mechanisms of single-cell induced changes in cortical activity. The setup allows simultaneous recordings of the spiking activity of multiple neurons across all layers of the cortex using a multi-electrode array, while manipulating the activity of one individual neuron in close proximity to the array. We demonstrate that single cells can be recorded and stimulated reliably for hundreds of trials, conferring high statistical power even for expectedly small effects of single-neuron spiking on network activity. Preliminary results suggest that single-cell stimulation on average decreases the firing rate of local network units. We expect that characterization of the spatiotemporal spread of single-cell evoked activity across layers and columns will yield novel insights into intracortical processing.
与单个神经元在群体活动中的作用微不足道的长期观念相反，最近的研究表明，仅单个皮层神经元的电激活就可以对全局脑状态、运动和感知产生可测量的影响。尽管这对于理解皮层神经元活动的协调方式非常重要，但这一现象背后的细胞和网络机制仍未解决。在这里，我们首先简要回顾了关于单细胞诱导网络调制现象的当前知识状态，并讨论了可能的基础。其次，我们展示了一种实验方法的原理证明，该方法可阐明单细胞诱导的皮层活动变化的机制。该设置允许使用多电极阵列同时记录皮层所有层的多个神经元的尖峰活动，同时在靠近阵列的地方操纵单个神经元的活动。我们证明，单个细胞可以可靠地记录和刺激数百次试验，即使单个神经元尖峰对网络活动的影响预计很小，也具有很高的统计能力。初步结果表明，单细胞刺激平均降低了局部网络单元的放电率。我们预计，对跨层和柱的单细胞诱发活动的时空传播进行特征描述，将为皮层内处理提供新的见解。
