Your eyes do weird things sometimes. Do you see little specks in the sky on a sunny day? Maybe you swear you saw a flash of light right at the corner of your vision, but it moved before you could see what it was. Does it ever appear as if there are zigzag lines over everything you look at? Or maybe your eyelid decided to twitch, making you feel like an angry cartoon character.

Do you know which of these is totally normal, which is your eyes trying to tell you something, and which one isn’t even an eye problem?

Specks in the Sky

What they are:
Are you seeing little specks that almost seem like a bit of dust drifting by? They tend to show up when you’re looking at something both clear and bright, like a white computer screen or sunny blue sky. And they always seem to dart out of view as soon as you try to catch a glimpse.

These are “floaters.” They are caused by proteins moving about in the fluid inside your eye. You’re actually seeing the shadow they make on your retina, not the protein itself.

What they mean:
Generally, these mean nothing. Although they can be annoying, they’re also a totally normal (but weird) thing your eye does. Floaters are always there. Sometimes, the light is just right so you can see them. Unless you notice a ton of them appear all at once, which is a sign of retinal detachment, they are perfectly normal.

Eye Twitches

What they are:
These are rapid, fluttering movements in your eyelid. Usually they happen in your lower lid but your upper lid or both of them can be affected.

What they mean:
Eyelid twitching that comes on suddenly is rarely a medical problem. However, they are a way your eyes try to get your attention. Notice what you are doing the next time you feel them. Using the computer? They are a symptom of digital eye strain and mean your eyes need a rest. Difficult day at work? Eyelid twitching might mean you are stressed and your whole body needs a break. Be careful with how you use that leisure time though. Both caffeine and alcohol can also cause these flutters.

Flashes of Light

What they are:
Flashes are just that: bursts of light. They may look like a camera’s flash or a streak like a lightning bolt.

What they mean:
There are two common causes of flashes, but only one has to do with your eyes. Remember the fluid the floaters were, well, floating in? This fluid is actually called vitreous gel and sometimes tugs on the retina and creates the flash. Infrequently, they aren’t a concern but if they accompany a sudden burst of floaters, they can be alerting you to an issue with the retina, in which case you should see your eye doctor immediately.

The other thing flashes of light may be is a migraine headache aura. People might also see zigzag lines or develop temporary blind spots. These occur about an hour or so before the onset of a migraine. Auras result when a chemical or electric signal travels through the part of the brain which processes your senses. Your eyes aren’t seeing these visual disturbances, your brain is. Therefore, although they affect your vision (temporarily), they aren’t even an eye problem.

Every part of our eyes, from the physical components to the sensory processing system, can introduce some strange visual quirks. Regular vision tests, wearing an up-to-date prescription, and treating your eyes with care will help you recognize which things are normal and which are not.

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