Ocular dominance plasticity disrupts binocular inhibition-excitation matching in visual cortex.
Ocular dominance plasticity disrupts binocular inhibition-excitation matching in visual cortex.
复制标题
眼优势可塑性破坏了视觉皮层的双眼抑制-兴奋匹配。
DOI：
10.1016/j.cub.2015.01.024
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Levelt,ChristiaanN
中科院分区：
文献类型：
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作者：
Saiepour,MHadi;Rajendran,Rajeev;Omrani,Azar;Ma,Wen-Pei;Tao,HuizhongW;Heimel,JAlexander;Levelt,ChristiaanN
背景为了确保神经元网络以稳定的方式工作，神经元接受平衡的抑制性和兴奋性输入。在大脑的不同区域，这种平衡被发现在可塑性过程中会暂时改变。目前尚不清楚抑制作用的改变对可塑性是有指导作用还是允许作用。一些研究以视觉皮质中的眼优势可塑性作为模型来解决这个问题，但到目前为止，抑制的变化是通过直接影响眼睛特异性反应还是通过增加兴奋性连接的可塑性潜力来驱动这种形式的可塑性仍然存在争议。结果我们测试了三种主要类型的中间神经元是如何通过光基因抑制正常饲养或单眼剥夺的小鼠的活动来影响眼睛特异性反应的。我们发现，与表达生长抑素或血管活性肠多肽的中间神经元相反，表达小白蛋白(PV)的中间神经元强烈抑制视觉反应。在正常小鼠的单个神经元中，由任一只眼睛驱动的抑制和兴奋是平衡的，抑制PV中间神经元不会改变视觉偏好。单眼剥夺破坏了单个神经元的双眼抑制和兴奋平衡，导致对PV中间神经元的抑制改变了它们的视觉偏好。然而，重要的是，这些变化并不总是有利于在群体水平上对其中一只眼睛的反应。结论单眼剥夺破坏了个体细胞抑制和兴奋的双眼平衡。这种不平衡并不影响眼睛优势的整体表现。因此，我们的数据支持抑制在眼优势可塑性中的允许作用，而不是指导作用。
BackgroundTo ensure that neuronal networks function in a stable fashion, neurons receive balanced inhibitory and excitatory inputs. In various brain regions, this balance has been found to change temporarily during plasticity. Whether changes in inhibition have an instructive or permissive role in plasticity remains unclear. Several studies have addressed this question using ocular dominance plasticity in the visual cortex as a model, but so far, it remains controversial whether changes in inhibition drive this form of plasticity by directly affecting eye-specific responses or through increasing the plasticity potential of excitatory connections.ResultsWe tested how three major classes of interneurons affect eye-specific responses in normally reared or monocularly deprived mice by optogenetically suppressing their activity. We find that in contrast to somatostatin-expressing or vasoactive intestinal polypeptide-expressing interneurons, parvalbumin (PV)-expressing interneurons strongly inhibit visual responses. In individual neurons of normal mice, inhibition and excitation driven by either eye are balanced, and suppressing PV interneurons does not alter ocular preference. Monocular deprivation disrupts the binocular balance of inhibition and excitation in individual neurons, causing suppression of PV interneurons to change their ocular preference. Importantly, however, these changes do not consistently favor responses to one of the eyes at the population level.ConclusionsMonocular deprivation disrupts the binocular balance of inhibition and excitation of individual cells. This disbalance does not affect the overall expression of ocular dominance. Our data therefore support a permissive rather than an instructive role of inhibition in ocular dominance plasticity.