This myth — or should we say half-myth — likely started with some faulty GE televisions in the 1960s, according to DNews. Staring at a screen for too long can cause eyestrain, but it won’t cause permanent damage to your eyes. So, to an extent, the advice is still on point: don’t sit to close to your monitor, and give yourself a screen break every 20 minutes or so to look at something 20 feet (6m) away. Your eyes will thank you. But don’t worry about permanent damage. Check out the video for more info.