Do you ever talk to yourself?
Be honest.
Researchers say talking to yourself, out loud, is more common than many of us might care to admit. Psychologists call it "self talk" and say how we do it makes a big difference in both our mood and our behavior.
Most people engage in self-talk, experts say, though some do it louder and more often than others. When I asked, I heard from people who talk to themselves in the basement, in their cubicle at work and at the urinal in the men's room. One woman turns the car radio down so she can hear herself better.
Self-talk is what happens when you make yourself the target of your own comments, advice or reminders. Experts consider it a subset of thinking. You're having a conversation with yourself.
Tell It Like It Is | It's OK to talk to yourself, with honest feedback and encouragement, experts say. 
My father talks to himself pretty much everywhere, including at the dinner table. He is more interested than anyone else is in what he has to say, he says. He taught my two sisters and me to high-five ourselves when we do something well.
Sometimes self-talk is automatic. Other times we do it deliberately to influence our own behavior. "What happens with self-talk is you stimulate your action, direct your action and evaluate your action," says Antonis Hatzigeorgiadis, associate professor at the University of Thessaly in Trikala, Greece, who studies self-talk and the psychology of sports performance.
Motivational self-talk includes what we say to psych ourselves up: "Come on!" "Let's go!" "You can do this!" Instructional self-talk walks us through a specific task. If you are driving, you might tell yourself to turn right at the next light, and then you do it. "It sounds simple, but you get the correct reaction," says Dr. Hatzigeorgiadis.
Instructional self-talk is helpful when learning or practicing a new sport or task, he says. For example, a swimmer can remind himself to keep his elbow high during freestyle. Before giving a speech, someone might tell herself, "Speak slower" and "Make eye contact."
It is important to be short, precise—and consistent. "You have to sustain it," Dr. Hatzigeorgiadis says. "You instruct yourself until it becomes automatic."
The way you address yourself matters, too. Research published in the Journal of Personality and Social Psychology in February found people who spoke to themselves as another person would—using their own name or the pronoun "you"—performed better under stress than people who used the word "I."
In one study, University of Michigan researchers induced stress in participants by telling them they had to prepare a speech to give to a panel of judges about their qualifications for a dream job. They were given five minutes to prepare and told they couldn't use notes.
Half the participants were instructed to work through their anxiety using the first-person pronoun ("Why am I nervous?"). The other half were told to address themselves by name or the pronoun "you" ("Why are you nervous?"). Afterward, each participant was asked to estimate how much shame he or she experienced right after the speech, and how much subsequent ruminating they did.
The results were consistent: People whose self-talk used their names or "you" reported less shame and ruminated less than the ones who used "I." The judges found the performances of those using "you" to be more confident, less nervous and more persuasive.
When people think of themselves as another person, "it allows them to give themselves objective, helpful feedback," says Ethan Kross, associate professor of psychology and director of the Self-Control and Emotion Laboratory at the University of Michigan.
Don Ingraham, a 77-year-old retired chief executive of a chemical distribution company, has been talking to himself for more than 70 years. He was a lonely child—his brothers were much older—and invented three imaginary friends, Bobby Palmer, Bobby Engine and Ainsley Oates, with whom he had regular conversations.
As an adult, Mr. Ingraham compliments himself when he does something well, such as the level base he built for an outdoor sink on the flagstone patio at his Austin County ranch, in Texas.
"Good job!" he said to himself. "You took the time to make it right." Sometimes, he scolds himself. He says it's his conscience speaking. While cleaning up tree branches after an ice storm this winter, he accidentally jabbed a sharp stick into his arm. "I used some barnyard words that follow the word 'dumb,' " he says.
Both positive and negative words can influence us in positive and negative ways. Say to yourself, "This job interview is going to be a cakewalk," and you might not get pumped up enough to ace it. Conversely, tell yourself, "You just lost that match, you need to focus harder," and it could spur you to do better in the future.
With critical self-talk, identify why you are being negative and focus on making it better. Don't say: "I bombed that presentation." Say: "That wasn't your best effort. You need to buckle down now and try harder."
Kathy Gruver, a 44-year-old alternative-medicine practitioner in Santa Barbara, Calif., once made herself cry while talking to herself about what to say to her then-boyfriend, who hadn't called when he said he would.
Since then, she has learned to speak to herself positively. She repeats daily affirmations, coaches herself on handling difficult clients and walks through the steps of her flying-trapeze workout. "I think it's healthy to talk to yourself," she says. "Throw your Bluetooth in, so people think you're on the phone, and let it all out."