PDA Gone Too Far

Ever found yourself in a public place, inadvertently bearing witness to a particularly amorous couple? They're lost in each others' eyes, smiling and laughing -- and displaying a level of affection you think should be kept behind closed doors?

What if it happened in a restaurant, when you were trying to eat a meal? Would you complain to the manager? Would you lose your appetite? Or would you watch the action and maybe even find yourself enjoying it?

"Primetime" asked actors to play overly affectionate couples in diners in New York and New Jersey and used hidden cameras to capture bystanders' reactions -- and some of the responses were surprising.

'Warm and Fuzzy Feeling'

In Brooklyn, a middle-aged couple was not only amused by the situation but seemed to enjoy it immensely. They even got a little into it themselves, declaring the space an unofficial "make out section," and displaying affection of their own.

Carrie Keating, psychology professor at Colgate University, says watching public displays of affection can sometimes have a positive effect on people.

"The very motor behavior, the tiny muscles of the face, the smiles, the gaze are often mimicked by observers and that very mimicry actually feeds back to the brain of the observer and gives you that sort of warm and fuzzy feeling inside," she says.

Bill, one of the patrons at the diner and a college professor, thinks Americans should take a lesson from the rest of the world.

"In France, they do that," he said. "Love is good. We need more of it."

But should people display that love in public?

One woman named Hilde wasn't as amused. Her friends didn't seem to be bothered, and at first, she, too, seemed okay with the public display of affection. But eventually she complained to the manager. Why, she asked, should she have to sit directly across from them?

Keating says this conflicted reaction is not uncommon. We may experience a range of feelings when we watch others engaging in PDA.

Some of the witnesses found the public displays of affection to be entertaining. In a diner in New Jersey, members of a social organization called the Red Hat Society watched our actors "go at it".

For the most part, the women got a kick out of the actors' antics, but there were a few exceptions. One woman glared at them, perhaps hoping to put an end to their canoodling. Eventually, she complained to the manager about their "inappropriate" behavior. But her society sisters continued to watch.

Getting Revenge

When one of the actors pretended to receive a call from his wife -- assuring her that he's at work -- the Red Hat ladies plotted revenge.

"Men are rats," said one woman. Another whipped out her camera phone and quickly took a photo of the two actors. A third woman wished she could get the number of the man's wife, to clue her in to her husband's infidelity. In the end, the sisterhood prevailed.

So if you happen to be dining in a restaurant next to an overly affectionate couple, what should you do?

"Before you intervene," says Keating, "it's best to know what the cultural rules are."

Standards of behavior -- what's appropriate and what's not in terms of affection -- vary from place to place.

"Maybe the litmus test is how many children are in the room," Keating concludes.