Andrew Huberman· PhD
Bringing your eyes to a single point in space will create a narrower aperture of a visual window, meaning your your visual world actually shrinks, at least perceptually. Now the caveat to this is that if you are going to look at a narrow space, a narrow window for any period of time, whether or not it's a book or a laptop or a tablet or a phone, those virgin's eye movements not only create alertness, but they also require energy and they also can fatigue the eyes because there's a process called accommodation whereby the shape of your eye literally has to change so that the lens can move so that you can focus at that location.