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All smiles: Joe Biden's laughing creates a lot of debate after the Vice Presidential debate

I think one of the most difficult things to do when you’re in a debate must be to keep your reactions in check while you’re not talking. Vice President Joe Biden was very animated Thursday night. I wonder if sometimes he isn't mindful that he is always on camera during a debate, or maybe it's just part of his technique.

NBC's David Gregory and Tom Brokaw discussed Biden's reactions in their post-debate commentary. See the video below.

NBC News

NBC News’ Michael O’Brien also reported on Biden’s debate reactions

The vice president threw up his arms, laughed, scoffed and rolled his eyes in reaction to Ryan’s attacks – a seemingly visceral reaction to what Biden frequently called “malarkey” offered up by the House Budget Committee chairman.

Biden’s response to Ryan’s proposals to reform Medicare into a “premium support” or voucher system was a typical refrain for the vice president: “Folks, use your common sense: who do you trust on this?”

NBC News analysis: Both Joe Biden and Paul Ryan performed their tasks well but may not have persuaded many undecided voters.

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