Section on Critical Brain Dynamics, Laboratory of Systems Neuroscience, National Institutes of Mental Health, Bethesda, Maryland 20892, USA.
J Neurosci. 2011 Jan 5;31(1):55-63. doi: 10.1523/JNEUROSCI.4637-10.2011.
The repertoire of neural activity patterns that a cortical network can produce constrains the ability of the network to transfer and process information. Here, we measured activity patterns obtained from multisite local field potential recordings in cortex cultures, urethane-anesthetized rats, and awake macaque monkeys. First, we quantified the information capacity of the pattern repertoire of ongoing and stimulus-evoked activity using Shannon entropy. Next, we quantified the efficacy of information transmission between stimulus and response using mutual information. By systematically changing the ratio of excitation/inhibition (E/I) in vitro and in a network model, we discovered that both information capacity and information transmission are maximized at a particular intermediate E/I, at which ongoing activity emerges as neuronal avalanches. Next, we used our in vitro and model results to correctly predict in vivo information capacity and interactions between neuronal groups during ongoing activity. Close agreement between our experiments and model suggest that neuronal avalanches and peak information capacity arise because of criticality and are general properties of cortical networks with balanced E/I.
皮质网络产生的神经活动模式的范围限制了网络传输和处理信息的能力。在这里，我们测量了皮质培养物、氨基甲酸乙酯麻醉大鼠和清醒猕猴的多部位局部场电位记录中获得的活动模式。首先，我们使用香农熵来量化正在进行的和刺激诱发的活动的模式范围的信息容量。接下来，我们使用互信息来量化刺激和反应之间信息传输的效率。通过系统地改变体外和网络模型中的兴奋/抑制比 (E/I)，我们发现信息容量和信息传输都在特定的中间 E/I 处最大化，在这个 E/I 处，正在进行的活动表现为神经元级联。接下来，我们使用我们的体外和模型结果来正确预测体内的信息容量和在正在进行的活动期间神经元群体之间的相互作用。我们的实验和模型之间的紧密一致表明，神经元级联和峰值信息容量的出现是由于临界性，并且是具有平衡 E/I 的皮质网络的一般特性。
