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Debate Body Language Actually Reveals Very Little

People love to speculate about what body language means — but how valid is the analysis?

As presidential candidates Hillary Clinton and Donald Trump prepare for their final debate on Wednesday night, they will be just as aware of their body language as their verbal language: What they do - when they smile or shake their head or shimmy their shoulders - will be meticulously analyzed and dissected by amateur and expert body language decoders alike.

Part of the reason for the interest in body language is that the public is eager for a glimpse of what the small motions and tics might unconsciously reveal. Debates are, of course, scripted events: The candidates memorize statistics that illustrate their points, practice "off-the-cuff" zingers, and rehearse ready responses to expected questions.

Even Trump, who has widely criticized Clinton for preparing for debates and denounced her as stiff and unauthentic, finally agreed to some preparation and use of teleprompters - sometimes. But the popular assumption is that body language is harder to control than words and so may reveal truer or more authentic personal beliefs and reactions.

So-called "body language experts" are routinely consulted to (over)interpret paparazzi photos of stars, and celebrity couples in particular. One expert opinion about a photo taken of Brad Pitt and Angelina Jolie in 2010 notes that "This half-hug shows, quite clearly, that Brad is only 'halfway' into Angelina. He embraces her with only one arm, and keeps the other on his tripod. He would really rather be taking pictures than touching her, this much is obvious." Six years later another body language expert offered her own detailed analysis of the state of the couple's dissolving relationship based on a few photos.

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CNN offered its take on "What Trump's, Clinton's Body Language at the Debate Revealed" (according to their expert Janine Driver, when the candidates shook hands at the end of the event, Trump "did that elbow grab, Like, 'I might be cowering down and shaking your hand and giving you power, but I'll take a little power back with that elbow grab.'") And the "Washington Post" offered two experts who advised readers what to look for in the next debate.

That nonverbal cues can reveal information about a person's intent and mood is well established in psychological literature. Much information is conveyed in a person's tone of voice, facial expressions, and so on, quite apart from the actual words they say or what they do.

But beyond the obvious cues - a smirk or sarcastic tone, for example - reading body language is much more of an art than a science. Scott Lilienfeld, a psychologist at Emory University and co-author of several books including "50 Great Myths of Popular Psychology," told Seeker in an e-mail that "As useful as body language can be in communicating information about emotional states, we must be careful in drawing conclusions about its meaning for any given person. Many pop psychologists specialize in 'translating' body language into emotions, as though there were a universal dictionary of body language. Yet these psychologists overlook the fact that even within a given culture, people differ greatly in the body language they use to express certain emotions."

Lilienfeld notes that "several body language experts interpreted then-presidential candidate Donald Trump's sniffling during his first presidential debate with Hillary Clinton as a sign of anxiety. But all such kinds of interpretations overlook the fact that there's no simple one-to-one translation of bodily gestures into emotions, largely because these nonverbal behaviors often mean very different things for different people." Fact-free speculative explanations for Trump's sniffles ranged from a cold or allergies to cocaine use.

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Many cross-cultural cues can confound an expert as well. The concept of appropriate personal space, for example, varies from person to person and culture to culture. What to one observer's eyes might seem too close (and thus predatory or aggressive) or too far (and thus emotionally distant or contemptuous) between two people may in fact be nothing of the sort.

Some people are huggers, others aren't. Did Trump lean toward Clinton to intimidate her, or because he couldn't hear her well, or because his feet hurt and he was shifting stances, or some other reason? Did Brad Pitt's half-hug of Angelina Jolie in one particular 2010 photo truly reveal his deep emotional indifference to her, or did he just not happen to passionately embrace her at that specific moment? Who knows? It's very difficult to draw valid conclusions about a person's motivations from little more than photos or video of them.

In the end, much of the body language analysis of the presidential debates is little more than a parlor game - but it's one that people love to play.

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