Neocortical Rebound Depolarization Enhances Visual Perception.
Neocortical Rebound Depolarization Enhances Visual Perception.
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DOI：
10.1371/journal.pbio.1002231
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发表时间：
2015-08
期刊：
影响因子：
9.8
通讯作者：
Ikegaya Y
中科院分区：
文献类型：
--
作者：
Funayama K;Minamisawa G;Matsumoto N;Ban H;Chan AW;Matsuki N;Murphy TH;Ikegaya Y
动物不断地暴露在随时间变化的视觉世界中。由于视觉感知是由之前的视觉经验调节的，视觉皮层神经元可以将最近的视觉历史记录到特定形式的离线活动中，并将其与后来的视觉输入联系起来。为了检查先前的视觉输入如何在单个神经元水平上与即将到来的信息相互作用，我们设计了一个简单的刺激方案，其中短暂的、定向的闪烁刺激随后与具有相同或不同特征的视觉刺激耦合。利用体内全细胞膜片钳记录和对清醒小鼠初级视觉皮层（V1）的功能性双光子钙成像，我们发现正弦光栅本身的闪光会诱导 V1 神经元的早期瞬时激活以及长期延迟的重新激活。这种延迟反应在闪光后数百毫秒开始并持续约 2 秒，在人类 V1 脑电图中也观察到。当另一个漂移光栅刺激在后期响应期间到来时，V1 神经元表现出亚线性但明显增强的响应，尤其是对相同的光栅方向。在小鼠和人类的行为测试中，只有当第二次刺激出现在晚期反应的时间窗口内时，闪烁刺激才能增强相同方向的视觉刺激的检测能力。因此，V1 晚期反应可能为混合时间上分离的刺激并在时变视觉环境中提取相同的特征提供了神经基础。对小鼠和人类的一项研究表明，视觉皮层的先前活动会引起长时间延迟的去极化，如果随后的视觉刺激与前一个刺激相同，则会增强对后续视觉刺激的感知，从而从不断变化的视觉世界中提取不变的视觉特征。动物不断地暴露在随时间变化的视觉世界中。为了检查视觉皮层如何整合时间间隔的视觉信息，我们使用单细胞和多细胞记录技术监测初级视觉皮层（V1）的神经元活动。我们发现，短暂的视觉刺激会诱导小鼠和人类 V1 神经元的早期短暂激活和延迟再激活。值得注意的是，视觉皮层的这种重新激活传达了有关刺激方向的信息：在重新激活期间呈现第二个视觉刺激会增强 V1 反应，特别是当两个刺激的方向相同时。对小鼠和人类的行为测试表明，在 V1 重新激活的时间窗口内出现第二次刺激时，检测视觉刺激的能力也会增强。由于动物从不断变化的环境中提取视觉信息，因此通过皮层重新激活来调节视觉反应可能是视觉系统中常用的策略。
Animals are constantly exposed to the time-varying visual world. Because visual perception is modulated by immediately prior visual experience, visual cortical neurons may register recent visual history into a specific form of offline activity and link it to later visual input. To examine how preceding visual inputs interact with upcoming information at the single neuron level, we designed a simple stimulation protocol in which a brief, orientated flashing stimulus was subsequently coupled to visual stimuli with identical or different features. Using in vivo whole-cell patch-clamp recording and functional two-photon calcium imaging from the primary visual cortex (V1) of awake mice, we discovered that a flash of sinusoidal grating per se induces an early, transient activation as well as a long-delayed reactivation in V1 neurons. This late response, which started hundreds of milliseconds after the flash and persisted for approximately 2 s, was also observed in human V1 electroencephalogram. When another drifting grating stimulus arrived during the late response, the V1 neurons exhibited a sublinear, but apparently increased response, especially to the same grating orientation. In behavioral tests of mice and humans, the flashing stimulation enhanced the detection power of the identically orientated visual stimulation only when the second stimulation was presented during the time window of the late response. Therefore, V1 late responses likely provide a neural basis for admixing temporally separated stimuli and extracting identical features in time-varying visual environments. A study of mice and humans shows that prior activity in the visual cortex induces a long-delayed depolarization that enhances perception of subsequent visual stimuli if these are identical to the previous one, thereby extracting invariant visual features from the constantly changing visual world. Animals are constantly exposed to a visual world that varies over time. To examine how the visual cortex integrates visual information that is temporally spaced, we monitored neuronal activity of the primary visual cortex (V1) using single- and multicell recording techniques. We discovered that a brief visual stimulus induced an early, transient activation as well as a delayed reactivation of V1 neurons in mice and humans. Notably, this reactivation of visual cortex conveyed information about stimulus orientation: presentation of a second visual stimulus during this reactivation enhanced the V1 response specifically when the orientations of the two stimuli were identical. Behavioral tests in mice and humans revealed that the ability to detect visual stimuli was also enhanced when the second stimulus was presented during the time window of V1 reactivation. Because animals extract visual information from an environment in constant change, the modulation of visual responses through cortical reactivation might be a strategy commonly used in the visual system.