Your Eye Twitches Can Be Explained by Science, Sort Of

"Are you winking at me?" asked the woman standing in line behind me in the cafeteria.

"No," I said over the paper rim of my tea, "my eye is twitching. It won't stop and it's driving me crazy."

The first time it happened, it started a week before finals during my last year at Columbia. It was a small tremor in the upper corner of my left eye. At first, it was weak, the sensation no more than a bizarre whisper of movement. As the week progressed, it got worse. Or rather, it felt worse. I kept drinking coffee and staying up late to study and the eyelid just kept twitching.

On the one hand, it was a small thing. On the other, it made me feel crazy. I couldn't control it and I worried that there was something wrong with me. Was it some kind of psychosomatic response to my looming thesis? Was it a sign that I was going insane? Was it going to get worse? Was I now suddenly going to start having seizures? I worried. The eyelid twitched.

Turns out that the answer to all my crazy hypochondria is the same as it usually is: There's nothing really wrong. "Eye twitching is a form of movement that we call a fasciculation," says Martin A. Samuels, chair of neurology at Brigham and Women's Hospital in Boston, about this bizarre occurrence. "A fasciculation is caused by a little nerve cell that sits in your spinal cord or in your brain and it sends an impulse to a muscle, and when that nerve impulse is sent to the muscle, the muscle jumps."

He tells me that almost every human feels these twitches sometimes in the muscles of the thighs, the calves, or in the hands. "The reason eye twitches are so common is that very few nerve cells supply the muscles that control the eyelid so it doesn't take very many of these to cause the eye to twitch," he adds.

It can happen anywhere in the body, in fact, and these fasciculations are happening all the time. But when the muscle that the nerve affects is tiny—as in, say, the eyelid—the nerve impulse of one cell is strong enough to make that muscle jump. That jumping causes the small joint of the eye to move, or twitch. A-ha. The mystery of the eye twitch is revealed.

So, but why? Why does it happen? How can I be sure that there's nothing really wrong with me? What causes this? Could there still be something wrong with me? I really seriously want to know if there's something wrong with me.

Payal Patel, an ophthalmologist at NYU's Langone Medical Center, says that we don't really know, but that some triggers can include fatigue, stress, and overuse of caffeine. Samuel agrees: "There's been a lot of effort over the years to try and figure out what causes these to happen. Everybody has their own personal theory but the reality is that they basically have a life of their own. They come and they go on their own. And there's no absolute relationship to anything we know of."

Usually these fasciculations happen in clusters, he adds. And they can continue for hours or sometimes days, and then they disappear for an unknown period of time. "And then they come back. They have no pathological significance at all." Basically, no one knows why my eye twitches. No one knows why yours twitches. But experts agree that it's no big deal. Patel says, "I spend most of my time with these patients just reassuring them that it's benign."

Okay, so it's no big deal. But when it happens, is there anything you can do about it? Patel suggests that eye twitching might be soothed by reducing screen time and caffeine and applying cool compresses. In chronic cases, some people get Botox. Obviously. The bad news (for the those who are creeped out by this already) is that these twitches are actually happening in your body all the time. Maybe even right now. The good news is that you now have a really good excuse to get Botox.

But what about other kinds of body twitches? Samuels says that these can also be caused by fasciculations. "When these things happen inside of bigger muscles—for example, the muscle of the thigh, the big muscle that extends the leg—your limb would not actually move. You might feel it, and you might see it if you happen to be looking right at that muscle. But it wouldn't be big enough, mechanically, to be able to kick your leg out." You'd just be able to feel it twitch.

Apparently, if bigger muscles move, then the actual limb might move—but that takes more than one of these little nerve cells. It takes several, Samuels says, and they all have to fire at once to affect enough muscle to make a body part actually move. "So if you see a twitch of a body part, which is not just a tiny little structure, then that's a different kind of movement called a myoclonus," he says.

"Myoclonus is also very common. These are big enough so that things can actually jump. One of the experiences that every human being has had is when you're falling asleep, every once in awhile, your whole body jumps. What's happened there is that enough cells have fired so that your body actually jumps," he elaborates. This happens to me all the time. Now can I worry?

No, says Samuels, who is turning out to be a relentless calmer of my twitch paranoia. "It's a completely normal phenomenon and it's called 'sleep starting.' You would only be worried about this if it were repetitive, recurrent, or unending. If you were to have a body part jerk and it wouldn't stop jerking, that would be something that would need to be examined and investigated a little bit." A little bit, he says.

Hiccups are another example of myoclonus. So these twitches we all feel don't have to mean you have a neurological disorder. You can just think of them as hiccups. They're nothing to get all hypochondriac about. But if you're feeling twitchy all the time, maybe it's time for Botox. You know, or a visit to an actual doctor.

Read This Next: How Bad Is it to Eat Really Fast?