Sagol School of Neuroscience and Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.
Department of Mathematics, Afeka-Tel Aviv College of Engineering, Tel-Aviv 6910717, Israel.
Sci Adv. 2024 Jan 19;10(3):eadj4411. doi: 10.1126/sciadv.adj4411. Epub 2024 Jan 17.
The precise timing of neuronal spikes may lead to changes in synaptic connectivity and is thought to be crucial for learning and memory. However, the effect of spike timing on neuronal connectivity in the intact brain remains unknown. Using closed-loop optogenetic stimulation in CA1 of freely moving mice, we generated unique spike patterns between presynaptic pyramidal cells (PYRs) and postsynaptic parvalbumin (PV)-immunoreactive cells. The stimulation led to spike transmission changes that occurred together across all presynaptic PYRs connected to the same postsynaptic PV cell. The precise timing of all presynaptic and postsynaptic cell spikes affected transmission changes. These findings reveal an unexpected plasticity mechanism, in which the spike timing of an entire cell assembly has a more substantial impact on effective connectivity than that of individual cell pairs.
神经元尖峰的精确时间可能导致突触连接的变化，被认为对学习和记忆至关重要。然而，在完整的大脑中，尖峰时间对神经元连接的影响尚不清楚。我们使用在自由活动的小鼠 CA1 中的闭环光遗传学刺激，在突触前锥体神经元 (PYRs) 和突触后钙蛋白 (PV)-免疫反应细胞之间产生了独特的尖峰模式。刺激导致了跨所有连接到相同突触后 PV 细胞的突触前 PYRs 共同发生的尖峰传递变化。所有突触前和突触后细胞尖峰的精确时间都影响了传递变化。这些发现揭示了一种意想不到的可塑性机制，即整个细胞集合的尖峰时间对有效连接的影响比单个细胞对的影响更大。
