Sang Tan/AP Photo

You're watching TV or maybe walking down the street, you pull out your phone, tap the power button and check to see if anyone has called, texted or tweeted. Sound familiar?

Well, you are not alone. According to a new report from the Pew Internet & American Life Project, 67 percent of cell phone owners find themselves checking their phone for messages, calls, tweets, etc., totally unprompted by a beep, ringing, or vibration. Of that 67 percent, 18 percent say they do that "frequently." Phew, there are others of us!

Similar to checking email, many psychologists and experts have long said that the brain gets a slight dopamine hit when people see a new message or e-mail. As Michael Chorost wrote in his book "World Wide Mind," "When you see you have a new email you don't know who it's from or what it's about, e.g., how gratifying the message will be - so you hope for that dopamine hit you'll get if its good."

Same goes for those mobile alerts and text messages, Chorost writes.

However, Aaron Smith, the author of the Pew report points out that another reason many check their phones is because of the social expectations.

"One factor may be the social expectation of availability. People tended to say that their friends were more likely to chide them for not responding promptly, than for being too attached to their phone," Smith said.

Still, many don't actually view their phone as a "time-waster," the report says. Only 3 percent agreed with the statement that their phone "costs you time because you are constantly being distracted and interrupted." Only 11 percent of cell owners say that they themselves worry they are spending too much time with their phone. Twelve percent of cell phone owners say people tell them they spend too much time looking at the phone.

The report didn't ask: what percent of users remember what they did before they had their phones to look at on the go!