Why we rarely notice our own blinking①. Our brains simply miss it， scientists say.
Visual sensitivity② starts decreasing just before we blink. But what goes on in the brain remained a mystery.
In the new study， scientists put fiber-optic lights in the mouths of people. The lights were powerful enough to penetrate③ the roofs of their mouths and strike their retinas④， where light is recorded. They wore goggles to block outside light.
When the test subjects blinked， the amount of light hitting their retinas didn’t change. Activity in their brains was monitored by functional magnetic resonance⑤ imaging. Scientists found that during blinking， brain activity was suppressed in areas that respond to visual input.
“Transiently suppressing these brain areas involved in visual awareness during blinks may be a neural mechanism for preventing the brain from becoming aware of the eyelid sweeping down over the pupil⑥ during a blink and the world going dark.”
Therefore， we rarely notice our own blinking.
① blinkvi. 眨眼睛；眯着眼看；闪亮，闪烁 vt. 眨(眼睛)
② sensitivityn. 敏感性；感受性；容易感受的性质；感光度
③ penetratevt. 穿过；刺入；透过；看透；识破
④ retinan. 【解】视网膜
⑤ resonancen. 共鸣；反响；【电】共振
⑥ pupiln. 瞳孔
眨眼睛的奥秘
为什么我们很少注意到自己在眨眼睛呢？科学家给出的答案是：仅仅是我们的大脑将它忽略了而已。
视觉敏感性会在人们眨眼之前开始变弱，但此时大脑内部又发生了什么？人们对此还不得而知。
在一项新的研究当中，科学家把光学纤维灯放置在人们的嘴里，而这种灯发出的光线足以透过人们的口腔上颚，到达视网膜。在视网膜内，光线被记录下来。同时，这些人还戴着护目镜，以阻挡来自外界的光线。
当参与试验的人们眨眼时，落到他们视网膜上的光线量没有发生变化。此时，他们脑部的活动由功能磁共振成像技术进行监控。科学家发现，在人们眨眼的过程中，他们脑部的活动在一个对视觉输入做出反应的区域内被抑制住了。
在眨眼的过程中，瞬间抑制这个和视觉意识有关的脑部区域可能是一种神经机制，这种神经机制可防止大脑意识到眼皮突然盖住瞳孔和世界因此变得漆黑一片。
因此我们很少注意自己在眨眼睛。
