Optogenetic Activation of Normalization in Alert Macaque Visual Cortex.
Optogenetic Activation of Normalization in Alert Macaque Visual Cortex.
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DOI：
10.1016/j.neuron.2015.05.040
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发表时间：
2015-06-17
期刊：
影响因子：
16.2
通讯作者：
Reynolds JH
中科院分区：
文献类型：
--
作者：
Nassi JJ;Avery MC;Cetin AH;Roe AW;Reynolds JH
归一化被认为是一种规范计算，它可以解释与感觉处理和高级认知功能相关的各种非线性神经元反应特性。归一化的一个关键前提是神经元的兴奋性与网络的整体活动水平成反比。我们通过光遗传学激活警觉猕猴初级视觉皮层中的兴奋性神经元并测量神经元活动的变化作为刺激强度的函数来测试这一点，有或没有可变对比度视觉刺激。兴奋性神经元的光遗传去极化促进或抑制基线活动，与抑制性网络的间接招募一致。正如归一化模型所预测的那样，神经元对光遗传学和视觉刺激表现出亚加性反应，这取决于刺激强度和亮度对比度。我们的结论是，即使在光遗传学刺激的人工条件下，标准化计算仍然存在，强调了这种形式的神经计算的规范性。
Normalization has been proposed as a canonical computation that accounts for a variety of nonlinear neuronal response properties associated with sensory processing and higher cognitive functions. A key premise of normalization is that the excitability of a neuron is inversely proportional to the overall activity level of the network. We tested this by optogenetically activating excitatory neurons in alert macaque primary visual cortex and measuring changes in neuronal activity as a function of stimulation intensity, with or without variable-contrast visual stimulation. Optogenetic depolarization of excitatory neurons either facilitated or suppressed baseline activity, consistent with indirect recruitment of inhibitory networks. As predicted by the normalization model, neurons exhibited sub-additive responses to optogenetic and visual stimulation, which depended lawfully on stimulation intensity and luminance contrast. We conclude that the normalization computation persists even under the artificial conditions of optogenetic stimulation, underscoring the canonical nature of this form of neural computation.