After the first televised presidential debate, held between John F. Kennedy and Richard M. Nixon 52 years ago, campaigns have been acutely aware that voters may judge candidates in such encounters as much by their appearance and gestures as by their words.

Peggy Hackney, an analyst working with the New York University Movement Lab, has examined the body language exhibited by President Obama and Mitt Romney in a number of speeches and debates. Here is a look at some of the signature gestures that they use.