Department of Mathematics, American University of the Middle East, Egaila, Kuwait.
Marcs Institute for Brain and Behavior, Western Sydney University, Sydney, Australia; School of Social Sciences and Psychology, Western Sydney University, Sydney, Australia.
Neural Netw. 2017 Jun;90:72-82. doi: 10.1016/j.neunet.2017.03.007. Epub 2017 Mar 22.
Persistent irregular activity is defined as elevated irregular neural discharges in the brain in such a way that while the average network activity displays high frequency oscillations, the participating neurons display irregular and low frequency oscillations. This type of activity is observed in many brain regions like prefrontal cortex that plays a role in working memory. Previous studies have shown that large networks with sparse connections, networks with strong noise and persistent inhibition and networks with structured synaptic connections display persistent-irregular activity. However, experimental studies show that, not all brain regions obey these assumptions. In this study we show that a small network of excitatory-inhibitory neurons with random synaptic connections can reproduce persistent-irregular activity. In particular, the model shows that less than perfect rebound pattern in excitatory cells, coincident-sensitive inhibitory cells and sparse synaptic inhibition can account for persistent-irregular activity in an excitatory-inhibitory neural network with randomly assigned synaptic connections.
持续性不规则活动被定义为大脑中异常神经放电的持续存在，其方式是，尽管平均网络活动显示高频振荡，但参与的神经元显示不规则和低频振荡。这种活动在许多脑区都有观察到，如在工作记忆中起作用的前额叶皮层。先前的研究表明，具有稀疏连接的大型网络、具有强噪声和持续抑制的网络以及具有结构突触连接的网络显示出持续性不规则活动。然而，实验研究表明，并非所有脑区都符合这些假设。在这项研究中，我们表明，具有随机突触连接的兴奋性-抑制性神经元的小网络可以再现持续性不规则活动。特别是，该模型表明，兴奋性细胞中不完全的反弹模式、同时敏感的抑制性细胞和稀疏的突触抑制可以解释具有随机分配的突触连接的兴奋性-抑制性神经网络中的持续性不规则活动。
