Centre for Neural Circuits and Behaviour, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.
Institute of Science and Technology, Klosterneuburg, Austria.
Commun Biol. 2022 Aug 25;5(1):873. doi: 10.1038/s42003-022-03801-2.
Changes in the short-term dynamics of excitatory synapses over development have been observed throughout cortex, but their purpose and consequences remain unclear. Here, we propose that developmental changes in synaptic dynamics buffer the effect of slow inhibitory long-term plasticity, allowing for continuously stable neural activity. Using computational modeling we demonstrate that early in development excitatory short-term depression quickly stabilises neural activity, even in the face of strong, unbalanced excitation. We introduce a model of the commonly observed developmental shift from depression to facilitation and show that neural activity remains stable throughout development, while inhibitory synaptic plasticity slowly balances excitation, consistent with experimental observations. Our model predicts changes in the input responses from phasic to phasic-and-tonic and more precise spike timings. We also observe a gradual emergence of short-lasting memory traces governed by short-term plasticity development. We conclude that the developmental depression-to-facilitation shift may control excitation-inhibition balance throughout development with important functional consequences.
在整个皮层中都观察到兴奋性突触在发育过程中的短期动力学变化，但它们的目的和后果仍不清楚。在这里，我们提出，突触动力学的发育变化缓冲了抑制性长时程可塑性的缓慢影响，从而实现了持续稳定的神经活动。使用计算建模，我们证明了在发育早期，兴奋性突触短时间抑制可以快速稳定神经活动，即使面对强烈的不平衡兴奋也是如此。我们引入了一个常见的从抑制到易化的发育转变模型，并表明在整个发育过程中，神经活动保持稳定，而抑制性突触可塑性缓慢平衡兴奋，与实验观察结果一致。我们的模型预测了从相位到相位和紧张的输入响应的变化，以及更精确的尖峰定时。我们还观察到由短期可塑性发展控制的短持续记忆痕迹的逐渐出现。我们得出的结论是，发育过程中从抑制到易化的转变可能会控制整个发育过程中的兴奋-抑制平衡，具有重要的功能后果。
