It's the nagging voice you hear in your head when you're tempted to have another cupcake or splurge on yet another pair of shoes. Or the constant inner chatter that pushes you to go for it when you're psyching yourself up to ask your boss for a raise.
We've all done it - talked to ourselves, that is. But it's not the first sign of madness after all, say scientists. In fact it's crucial for self-control, especially when it comes to curbing impulsive behaviour.
"We give ourselves messages all the time, whether that's telling ourselves to keep running when we're tired, to stop eating even though we want more, or to refrain from blowing up on someone in an argument," explains Alexa Tullett, a researcher at the University of Toronto.
Alexa and her team wanted to find out if that inner voice is a helpful mechanism for everyday life. So they gave volunteers a series of bizarre-sounding tests, some of which involved resisting pushing a button while repeating a word over and over (the idea was to stop the volunteers talking to themselves while doing the test).
They discovered that when people couldn't use their inner voice, they acted more impulsively. "Talking to ourselves actually helps us exercise self control and prevents us from making impulsive decisions," adds Alexa.
But what do you think? Does your inner voice talk you out of doing things you might regret, or does it work the other way? What's the best or worst thing you've talked yourself into (or out of)?