Why did Ryan Lochte lie? Maybe because he - and all of us - were born this way?

"It doesn't surprise me. People typically lie under stress. When in fear, people lie," says Dr. Melinda Paige, who teaches clinical medical health counseling at Atlanta's Argosy University.

Lochte, the multiple Olympic medal swimmer, had reported that he and several team members were robbed at gun point outside their cab while returning to the Olympic Village in Rio. Not only did details in Lochte’s story change with subsequent tellings, but Brazilian police officials, a gas station security tape that apparently shows the swimmers kicking down a bathroom door and fighting with a security guard, and now, reportedly, Lochte’s own friends, are contradicting his original account.

Psychology experts say that human beings have various reasons for bending the truth or even telling a straight-up whopper, but they mostly come back from having something to lose.

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"There are lots of reasons people lie - guilt, shame, inventing a better self-image or to avoid getting in trouble," says Dr. Rachel Needle, a licensed psychologist at West Palm Beach's Whole Health Psychological Center. "Lying can get us out of awkward situations."

Those awkward situations, Paige says, might trigger stress, which impacts the brain’s limbic system which “is programmed for survival.”

In Lochte’s case, survival means protecting “what really matters to him, like public perception,” Paige says. “(That part) of the brain is about alarm and safety, not about rational thought. It’s mobilized for fight or flight, and that protection is of his image, or to the United States, which he represents as an athlete.”

Paige adds that this natural stress reflex to lie, even when it's a really dumb lie, can be seen on reality TV competitions when a contestant straight-up fibs about something that, if they were calm and able to think rationally, can be disproven because they're being filmed 24/7. And it's why politicians and their campaigns lie about obvious things – see the initial remarks from Donald Trump's campaign that wife Melania's Republican National Convention speech was absolutely not identical to an earlier one by First Lady Michelle Obama, even though it clearly was.

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Needle says it may be notable that Lochte was in a group when the alleged story was concocted, because "there's potential (for it) to spiral into an even bigger lie. No one's going to ever know who started the lie, but in a group it's easier to feel more safe and comfortable in contributing to that lie with other people supporting you in that lie. It seems potentially easier to get away with."

For celebrities, sometimes there’s the “thrill of telling a lie and getting away with it,” says Manhattan-based psychologist Jonathan Alpert, author of “Be Fearless: Change Your Life In 28 Days.” Celebrities like Lochte might feel more confident that they won’t be caught and that their stories are more believable because they are in the public eye and are given the benefit of any doubt. “They might feel they are immune from being caught.”

Alpert adds that the motivation for lying might be determined by gender. Women “tend to lie more to their friends. They may say an outfit looks great on someone when it really doesn’t,” while men “lie to look better. It might come in the form of boasting. I help many clients navigate the world of dating apps where lies are plentiful. Men typically add an inch or two to their height, for instance. The lies build themselves up. It’s also a way to exert control over others, a situation, or even themselves if they feel they have no control.”

Dr. Nicki Nance, professor in the Psychology and Human Services department at Beacon College in Leesburg in central Florida, says that it’s not that celebrities and “people in the public eye are lying more than other people, but that they look more stupid because more eyes are on them when they do it. In (normal) life, we lie to our parents and spouses, but we don’t have the whole world looking at our lies.”

Nance says she wonders if the swimmers’ apparent untruth “was to provide context for an excuse, because they were going to be telling a bigger lie later… What guy do you know kicks down a door to pee? They pee wherever they are. I didn’t believe that part of it.”

Nance says another dynamic might be at work. “A lot of times, people under that kind of pressure get a little freedom and are just tired of being good. You think of your freshman year in college where you’re expected to make mistakes. But if you never had that period, you might as well do it in Brazil.”

We might never know the specific reasons Lochte and his fellow swimmers chose to tell a story that is now falling apart like so many shattered records.

“But his swimming is great,” Nance says wryly.