Miley Cyrus has opened up about why she's always sticking out her tongue: because she doesn't "know how to smile."

The singer says that she can't help sticking her tongue out when the cameras are rolling because it feels "awkward" for her to just crack a smile.

"I get embarrassed to take pictures. That's actually the truth," she told ABC's Barbara Walters during her 'Most Fascinating People' interview.

"I'm so embarrassed," she adds," because people are taking pictures of me, and I just don't know how to -- I don't know how to smile, and just be awkward, so I stick my tongue out, because I don't know what else to do."

Miley also says that because of all of her stage antics she stays away from reading what her critics are saying about her. Most accuse her of being "desperate" for the attention.

“I know I’m not [desperate], so that’s why I just kind of laugh,” she says. “I refuse to Google myself. The minute I stopped Googling myself, you don’t imagine what a happier person I am.”