Rocking back and forth

A couple days ago I blogged a video of Jesse Ventura discussing the CIA's role in state government. A question was asked in the comments section re the possible significance of Ventura's rocking back and forth during his presentation (it's so evident in the video that you can't help but notice it.)

I didn't have a quick answer, so I asked my wife, who suggested it could be sign of autism - noting that Bill Gates is also famous for his rocking back and forth. I found that observation well documented in the Time magazine profile of him in 1997:

His face suddenly becomes expressionless, his squeaky voice turns toneless, and he folds his arms across his belly and vigorously rocks back and forth in a mannerism that has become so mimicked at Microsoft that a meeting there can resemble a round table of ecstatic rabbis.

Boing Boing blogged a Bill Gates video (embedded above) and added this comment:

"that autistic rocking is pretty characteristic."

Dustin Hoffman also rocked back and forth during some scenes in Rainman. Is Ventura autistic? He has participated in autism fundraisers in the past, but that could have been as a result of his position as governor of Minnesota. I don't know whether he's autistic or not, nor does it really matter, since this isn't a celebrity blog. But the behavior itself is interesting, and I wonder what other medical or behavioral associations it may have.