When it’s due to extended screen use, it’s known as digital eye strain or digital eye fatigue. In fact, between remote work and the rise of digital devices, this is most likely what you’re experiencing when you have eye discomfort.
So, how does eye strain happen, exactly? It comes down to the ciliary muscles in your eyes. Don’t underestimate these tiny muscle. They control your lens, allowing you to focus on objects at different distances.
“When we focus on objects more than 20 feet away, the ciliary muscles relax and the lens flattens out,” explains Karen Hecht, Ph.D., scientific affairs manager at AstaReal®. But when we focus on objects up close (i.e., less than 20 feet away), the ciliary muscles contract to round the lens, she says.
Thus, when you’re focusing on close objects (like a screen) for hours on end, your ciliary muscles are contracting, or flexing, for a long time. “It’s like holding a plank or squatting for hours, the burn will be real,” explains mbg’s vice president of scientific affairs Ashley Jordan Ferira, Ph.D., RDN. This prolonged contraction for near focus activities essentially burns out your ciliary muscles, resulting in eye strain.