Well because, unnoticed by you or me, our eyes are always moving in these microscopic little flutters called saccades to make sure that the stimulation on our visual receptors is always changing.

好吧，因为在你或我没有注意到的情况下，我们的眼睛总是在这些称为扫视的微观小颤动中移动， 以确保对我们视觉感受器的刺激总是在变化。