Intelligence isn’t about your world knowledge, but is instead the speed at which you learn new information. Unfortunately, studies in the past have found that IQ is fixed, so you’re essentially stuck with it for the rest of your life.

To be honest, so many of us don’t even know if we’re smart or not. You can’t exactly measure it unless you’re willing to spend a heap of money with a trained professional.

But there are some interesting signs that science says might be common for many intelligent people. They are:

1. You’re anxious.

Nobody likes having anxiety, but science has consistently found that those who experience anxiety to be smarter. One study found that the worse the symptoms of people with anxiety disorders, the more intelligent they were. What’s more, another study found that anxious participants were more focused and effective at executing tasks. So if you’re worried about worrying, maybe you don’t have to worry anymore.