听力文本

Because the space and the white blood cells are both more transparent to blue light than the red blood cells normally present in capillaries,
由于这些空隙和白细胞本身相比于血管中的红细胞更能让蓝光透过我们，
we see a moving dot of light wherever this happens, following the paths of your capillaries and moving in time with your pulse.
因此看到小光点沿着毛细血管移动也随着脉搏而移动。
Under ideal viewing conditions, you might even see what looks like a dark tail following the dot.
在理想状况下甚至会看到光点后有条黑尾巴。
This is the red blood cells that have bunched up behind the leukocyte.
这是白细胞身后堆积的红细胞造成的。
Some science museums have an exhibit which consists of a screen of blue light,
有些科技馆中会展览出一整屏幕的蓝光
allowing you to see these blue sky sprites much more clearly than you normally would.
这会让你跟清楚的看到这一现象。

While everybody's eyes experience these sort of effects, the number and type vary greatly.
因为虽然每个人都会经历这些现象，每个人看到的程度都不同。
In the case of floaters, they often go unnoticed, as our brain learns to ignore them.
就飞蚊症而言大多数会被我们的大脑所忽视。
However, abnormally numerous or large floaters that interfere with vision
但是数目异常多或者大到影响视线的飞蚊，
may be a sign of a more serious condition, requiring immediate medical treatment.
可能意味着你需要紧急医疗救助。
But the majority of the time entoptic phenomena, such as floaters and blue sky sprites,
但是多数的眼内现象，比如飞蚊或者谢瑞尔氏现象，
are just a gentle reminder that what we think we see depends just as much on our biology and minds as it does on the external world.
只是委婉地提醒我们自认为看到的东西取决于我们的生理和大脑，就和取决于外部世界一样。

演讲介绍

我们有时会突然发现，视野里有像灰尘或者虫子样的透明物体在飘荡，目光尾随过去又会立刻消失，非常奇妙。对此，向学生提供教育内容的TED-Ed通过图片解说了这种“透明漂浮物”的真面目。