Why Do We See Stars When We Rub Our Eyes?
来源: https://www.sciencefocus.com
These shapes and colours, called 'phosphenes', were reported as long ago as the time of the ancient Greeks. Rubbing your eyes increases the pressure within the eyeball and this pressure activates ganglion cells in the retina in the same way as light does. Your brain doesn't know the difference and so interprets the activation as though you were seeing light from the world outside.
这些形状和颜色被称为“幻视”，早在古希腊时期就有记录了。揉眼睛会增加眼球内的压力，这种压力会以与光线相同的方式激活视网膜上的神经节细胞。大脑不知道其中的区别，因此会将这种激活解释为看到了来自外部世界的光线。
Most common phosphenes are diffuse blobs of different colours that move with the rubbing. Then there are scintillating and rapidly moving grid-like patterns which probably reflect the organisation of cells higher up in the visual system.
最常见的幻视是随摩擦而移动的不同颜色的漫射光团。然后是闪烁和快速移动的网格状图案，这可能反映了视觉系统中更高层细胞的组织结构。
Within our eyeballs, there's a type of neuron called the retinal ganglion cell whose job is to receive visual information from the light-sensitive photoreceptor cells in the retina, the lining inside the back of your eyeball. Usually, we see the world because the retinal ganglion cell receives information from photoreceptor cells that being stimulated by light entering the eye.
在我们的眼球中，有一种叫做视网膜神经节细胞的神经元，它的工作是接收视网膜（眼球后部的内膜）中感光细胞发出的视觉信息。通常，我们之所以能看到世界，是因为视网膜神经节细胞接收了来自感光细胞的信息，而感光细胞受到了进入眼球的光线的刺激。
However, it's also possible to activate the retinal cells through applying pressure. Gently pressing into your eye will apply pressure to the cells within the retina, "tricking" them into firing off in a similar way to activation by light. Totally unable to differentiate the stimulation, the central nervous system will perceive it in the same way it would seeing light. Even a sneeze or a cough is enough for some people to spark up a small phosphene.
但是，我们也可以通过施加压力来激活视网膜细胞。轻轻按压眼睛会对视网膜内的细胞施加压力，“诱使”它们以类似于光激活的方式发射信号。中枢神经系统完全无法区分这种刺激，而会以看到光的相同方式感知它。对某些人来说，即使是一个喷嚏或一声咳嗽也足以引发一个小磷光体。
Other effects include an array of intense blue points of light. If you want to experience these, be careful and press gently for some time rather than pressing too hard and risking damage to the eye.
其他效果包括一系列强烈的蓝色光点。如果你想体验这些效果，一定要小心，轻轻按压一段时间，不要用力过猛，以免损伤眼睛。