When the head rotates, the eyes automatically rotate in the opposite direction to compensate and maintain a stable visual field.

“When you suddenly rotate your head to the left, your eyes are actually rotating to the right automatically. You you do this in complete darkness. If you had an eye infrared camera and watched yourself in complete darkness, you can't see anything. Rotating your head to the left, your eyes would rotate to the right. That's your vestibular system saying, I'm going to try to compensate for the head rotation so my eyes are still looking in the same place.”