Rob on Ellen

Is Robert Pattinson shy? The 'Twilight' star offers fans everywhere a glimpse into his mind on Wednesday's "The Ellen DeGeneres Show."

On the program, Ellen comments that Rob seems more at ease acting than chatting on a talk show, and she says she thinks he might be shy.

"I just like doing things where you have a little time to think about what you're saying," Rob replies. "I've always had a problem actually thinking before I open my mouth."

"Being spontaneous?" Ellen asks.

"Yeah, being spontaneous or just thinking. I have a problem with thinking… Thinking in real time," he explains.

Catch Rob thinking about romancing Kristen Stewart's gorgeous Bella in 'The Twilight Saga: Eclipse,' in theaters June 30.