In his book "Why Presidents Succeed," University of California at Davis psychologist Dean Keith Simonton argues that the most effective communicators use concrete — rather than abstract — language.

"'I feel your pain' has association," he tells the APA Monitor, "but 'I can relate to your viewpoint' doesn't. The most charismatic presidents reached an emotional connection with people talking not to their brains but to their gut."

"Charismatic individuals express their feelings spontaneously and genuinely," Claremont McKenna College psychologist Ronald E. Riggio says. "This allows them to affect the moods and emotions of others."

It's called emotional contagion, or "the tendency to automatically mimic and synchronize expressions."

So if you're really excited about something, other people with "catch" that excitement, too.

A Stanford-Harvard study recently cited on Marginal Revolution suggests that accomplishments aren't what capture people's attention — rather, it's a person's perceived potential.

"This uncertainty [that comes with potential] appears to be more cognitively engaging than reflecting on what is already known to be true," the authors write.

Psychologists have found that when two people are getting along, they start to mirror each other's bodies as a sign of trust and safety. Your date crosses their legs, so do you; you take a sip of water, so does your date. 

If you want to do better in a negotiation, the research says to mimic your opponent's behavior.

In a Durham University study, students were shown video clips of 26 other students walking — some with looser gaits, some tighter. 

Just a few steps were needed to give a sense of personality. Students equated looser gaits with extroversion and adventurousness, while the more clipped walkers were seen as neurotic.

A University of Illinois at Urbana-Champaign study on walking speeds showed that guys match women's walking paces if they're attracted to them.

Body language experts agree that posture speaks louder than words. 

Keeping your hands stuffed in your pockets and your shoulders turned inward sends the signal that you're not interested. But talking with your hands and standing in an open stance shows that you're available. 

In a University of Michigan experiment, women read vignettes about men. Whenever the story featured a person who owned a dog, women rated them with higher long-term attractiveness.

The researchers concluded that owning a pet signaled that you're nurturing and capable of making long-term commitments. It also makes you appear more relaxed, approachable, and happy. 

In two experiments, researchers in Switzerland examined the relationship between attractiveness and smiling.

They found that the stronger the smile, the more attractive a face looked. 

In fact, a happy facial expression compensated for relative unattractiveness.

According to Harvard research, talking about yourself stimulates the same brain regions as sex or a good meal. 

"Activation of this system when discussing the self suggests that self-disclosure ... may be inherently pleasurable," Scientific American reports. 

And when people talk about their experiences, they become more vulnerable to one another, and when they become more vulnerable to one another, they form social bonds and coinvest in one another's welfare. 

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