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Jill, Ann, and Kimberly go off to college with warnings from their parents about sex and the “Freshman 15” ringing in their ears. Months later, Jill has gained 15 pounds and Ann has become a sexual adventurer. Kimberly, on the other hand, has not only maintained her weight, she's been too busy studying in the library stacks to hook up.

What accounts for the differences?

It could be the way each one’s brain reward center responds to food and sexual cues, reports a new study.

According to research out of Dartmouth College, in some people, hyperactivation of the nucleus accumbens, a key reward structure buried within the brain's striatum, predicted the eating and sexual behaviors of people (in this case, a group of freshmen women).

This suggests one’s ability to say “no” is not just a matter of willpower, but brain wiring.  

The study, published this week in the Journal of Neuroscience, used fMRI brain imaging and pictures depicting food, erotica, landscapes, and people to gauge how the test subjects' accumbens reacted to each stimulus. (The 48 women who completed the study had no idea what it was actually about.)

Six months later, the women returned to the lab where they were weighed and asked to fill out a questionnaire. Those whose accumbens reacted especially strongly to food cues had gained more weight. And those who reacted to sexual cues most strongly were more likely to have had sex and report stronger sexual desire.

Interestingly, their "appetites" did not cross over. The women with hyperactive responses to sex cues did not have a hyperactive response to food and vice versa.

Bill Kelley, associate professor of Dartmouth's department of psychological and brain sciences, says the study shows that the activation of one brain region proved to be a strong predictor of later behavior, demonstrating that the stronger the “liking” response to a stimulus, the less able we are to “hear” our rational brain saying “no.” 

But are we born this way, or do we acquire stronger craving for specific rewards?

“That’s a great question,” said Kathryn Demos, who led the study and is now an assistant professor of psychiatry and human behavior at Brown University.

Kelley thinks that since different women were tempted by different things, their brain wiring has developed through experience, aided by a genetic component.

Luckily, there are tools that can help people blunt the power of their brain wiring. Behavioral therapies, for example, have had some limited success in people who seem strongly stimulated by food. 

People can also try to replace various cravings with something more healthful, for instance, going for a run whenever they're tempted to eat a cheeseburger.

As for the findings, Demos says the idea that all people are equally capable of self-control is naïve.

Reward, she says, “is a very powerful system.”

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young PhD., of The Chemistry Between Us: Love Sex and the Science of Attraction, to be published September 13.

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• All that stress is shrinking your brain, study finds
• Facebook takes a toll on your mental health

Even though Americans are marrying older, the divorce rate has remained high, a new government report shows.

Centers for Disease Control and Prevention researchers found that the median age for women getting hitched for the first time has risen to almost 26 and to over 28 for men.

Among women there was just a 52 percent chance that a first marriage would survive for 20 years, according to the report from the CDC’s National Center for Health Statistics. Men appeared to be slightly more successful, with a 56 percent chance of a first marriage surviving for two decades.

The older marriage age doesn’t mean that people aren’t getting into relationships – they’re just choosing to live together instead.  “There’s been a real rise in the prevalence of cohabitation,” said the report’s lead author, Casey E. Copen, a demographer with the National Survey of Family Growth at the National Center for Health Statistics.

The percentage of women living with a partner (as opposed to marrying him) has nearly quadrupled from 3 percent in 1982 to 11 percent in the newest survey. The earlier surveys included data only from women so the researchers couldn’t look at whether there had been a change in the rate at which men were choosing to live together rather than to marry.  

The new report includes information from 22,682 Americans between the ages of 15 and 44 who were interviewed in their homes between 2006 and 2010. The researchers also had data from six earlier surveys dating back to 1973 to compare with the new information.

One intriguing finding from the study is that more highly educated people wedded later -- and had longer lasting marriages. Copen and her colleagues found that 78 percent of women with at least a bachelor’s degree had made it to their 20^th anniversary as compared to 41 percent of women with only a high school diploma. Similarly, 65 percent of college educated men saw a 20^th anniversary as compared to 47 percent of the men who hadn’t gone beyond high school.

That falls in line with other new research showing that blue collar folks are less likely to get married than their white collar counterparts, Copen said. “Research has shown that there’s a socioeconomic divide between those who marry and those who don’t,” she added. “People may be more likely to transition to marriage when they feel more economically stable.”

The researchers also found that the lack of a marriage certificate isn’t keeping people from having babies. “A lot of women and men have children while cohabitating,” Copen said.

So, did the new report shed any light on what it takes to stay married? Maybe - depending on how you interpret the results.

For one thing, if you want to stay hitched, you probably shouldn’t choose someone who’s gotten divorced. Looking only at first marriages, just 38 percent of women who chose to wed a divorced man were still married by their 20^th anniversary, as compared to 54 percent of those who wed a man who’d never been married.

Another possible predictor of a shortened wedded bliss: marrying someone who already has kids. Looking only at women in a first marriage, just 37 percent of those marrying a man with kids made it to their platinum anniversary as compared to 54 percent of those who wed a man with no children.

Still, children may indeed be the glue that keeps people together – if they’re conceived and born after the couple marries.

Among women who remained childless just 50 percent reached their platinum anniversary as compared to 77 percent of those who bore children at least 8 months after getting married.

In the end, the report may be telling us something good about the way Americans view marriage.  

Although women are taking longer to decide to get hitched, they are still doing it at about the same rate as they were back in 1995.

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Adjusting to the daylight saving time switch can be toughest for night owls and people who are sleep-deprived.

For many Americans, the switch to daylight saving time is an annual rite of exhaustion. Gaining that extra hour of daylight at night means losing it in the morning. 

The time shift disrupts the body's natural circadian rhythm, according to sleep scientists. So the alarm clock blares just as your internal sleep-wake cycle orders you to stay snugly in bed. 

It's always harder to adjust to the "spring ahead" time change (as we did Sunday morning) than to the "fall back" change (on November 4), just as it's harder to fly east than west. Circadian rhythms are likely genetically determined and not fully understood. 

But research shows that the natural sleep-wake cycle is slightly longer than 24 hours. Therefore, "the circadian clock prefers us to extend our sleep in the morning when permitted," making it easier to stay asleep later than to fall asleep earlier, said Dr. James Wyatt, a specialist in sleep disorders at Rush University Medical Center in Chicago and a spokesman for the American Academy of Sleep Medicine.  

Genetic traits also determine your chronotype -- whether you are a night owl or a morning lark. Owls tend to have more difficulty with the daylight-saving shift, Wyatt said.

People vary greatly in their reactions to the sleep deprivation prompted by the time change.  Some 70 to 80 percent of people aren't significantly bothered, said Dr. Shyam Subramanian, director of the sleep center at University Hospitals Case Medical Center in Cleveland, and can adjust successfully in a day or two. Others yawn their way through the week.

For them, the consequences can be grave. Rates of workplace and traffic accidents, as well as of heart attacks, rise in the days following the spring time change. One study showed a nearly 6 percent rise in workplace injuries on the Monday after the daylight-saving switch. 

People already sleep-deprived are likely to have the toughest time. "With work, school, family and social obligations, most of us carry a chronic sleep debt into the weekend," Wyatt said. 

Wyatt and other researchers say people then spend the weekend trying to catch up. Even if they go to bed earlier, they can't easily fight their circadian rhythm. So they end up lying awake.

Though some argue that the time change is "just an hour," that amount of time is not insignificant, said Phyllis Zee, a professor at Northwestern University in Evanston, Ill., who is president of the Sleep Research Society. 

People who are nodding off will insist that they are "just resting their eyes," said Zee. "But the data shows they are impaired from an attention and safety standpoint. People are not aware of their level of impairment." 

Sleep experts suggest the following tips to dealing with the time switch:

• Perk up with coffee or another caffeinated beverage in the morning; avoid caffeine in the afternoon and evening.  
• Expose yourself to daylight soon after waking. Doing so helps adjust the circadian rhythm.
• Avoid bright light in the evening. Computer screens mimic daylight and throw your circadian rhythm off. 
• Practice good sleep habits, with a comfy bed, a quiet room and white noise to drown out sounds if necessary. 
• Be especially careful while driving or engaging in other activities requiring full alertness.  

By Stephanie Pappas
LiveScience

Facebook's initial public offering of stock is likely to make a lot of developers and designers of the site very wealthy. But for many users, frequent Facebooking may not be so beneficial.

According to three new studies, Facebook can be tough on mental health, offering an all-too-alluring medium for social comparison and ill-advised status updates. And while adding a friend on the social networking site can make people feel cheery and connected, having a lot of friends is associated with feeling worse about one's own life.

The thread running through these findings is not that Facebook itself is harmful, but that it provides a place for people to indulge in self-destructive behavior, such as trumpeting their own weaknesses or comparing their achievements with those of others.

Take status updates. Most people know that their Facebook friends tend to craft these online-wall memos on what they're up to in a way that puts their lives in the best light, said Mudra Mukesh, a doctoral candidate in marketing at the Instituto de Empresa in Madrid. But when it comes down to actually using the site, reading other people's status updates still makes Facebookers feel worse. [Facebook's Global Reach (Infographic)]

In research presented earlier this month at the annual meeting of the Society for Personality and Social Psychologists (SPSP) in San Diego, Mukesh and her co-author Dilney Goncalves found that when people think about the last time someone asked to friend them on Facebook, they get a boost in feelings of belonging and social connectedness ­— the kind of feeling that makes people "sing 'Kumbaya,'" Mukesh told LiveScience.

But once you've collected all those friends, viewing their status updates is a downer, Mukesh said. When asked how they felt about their place in life and their achievements, people with lots of Facebook friends gave themselves lower marks if they'd just viewed their friends' status updates, compared with people who hadn't recently surfed the site.

For people with just a few friends, viewing status updates wasn't a problem.

"A small number of friends means a low probability of viewing others showing off," Mukesh said. For people with lots of friends, though, the Facebook Newsfeed turns into a parade of good news about other people's live: promotions, engagements, weddings and new babies. Even if someone knows intellectually that people use Facebook to show off, Mukesh said, all of this information can make them feel worse about their own achievements or lack thereof. [10 Technologies That Will Transform Your Life]

(In Mukesh's study, 354 friends was the cut-off point for when participants started to feel bad about viewing status updates. But that's not a universal number, she cautioned, just the number that applied given the statistics of her sample.)

In another study presented at the SPSP conference, researchers at the University of Houston surveyed college students and found that time spent on Facebook is linked to depressive symptoms. That doesn't mean Facebook causes depression, but that depressed feelings and lots of Facebooking tend to go hand in hand, for whatever reason. For young men, the study found, the link seemed to be a tendency to compare oneself with others.

"It appears as if males, when they socially compare themselves on Facebook, they tend to experience depression systems," study researcher and University of Houston doctoral student Mai-Ly Nguyen told LiveScience.

In this case, Facebook seems to be a new medium for men to compete with one another, Nguyen said. Outside the digital realm, men often compare themselves with one another, she said. It may be that women more often use the site to connect with one another and men to compete with one another.

Some people, however, don't use their Facebook status updates to pump themselves up. Instead, they complain.

People with low self-esteem view Facebook as a safer place to express themselves than in face-to-face interactions, according to new research published in the March issue of the journal of Psychological Science. All this venting may actually alienate friends.

Researchers led by Amanda Forest of the University of Waterloo in Ontario collected recent status updates from 117 participants who also reported their average time spent on Facebook and answered questions to reveal their self-esteem levels. Some statuses were chipper, such as "[Poster] is lucky to have such terrific friends and is looking forward to a great day tomorrow!" Others wallowed in bad news: "[Poster] is upset b/c her phone got stolen :@."

Next, the researchers had another group of participants read the status updates and rate how much they liked the person who wrote each. Unsurprisingly, people responded more positively to posters whose updates were positive.

Of course, you'd expect friends to be a little more caring than strangers. So the researchers set up another experiment in which they collected recent status updates from 98 undergraduates and also asked the students to submit the number of likes and number of comments on each.

It turned out that for users with high self-esteem, a negative post garnered more responses than a positive one, presumably because those people's friends were concerned about the out-of-character update. For users with low self-esteem, though, negative posts seemed to exhaust friends: They got few responses.

"Indeed, [low-self-esteem users'] friends rewarded their posts with more validation and attention the more positive they were, perhaps trying to encourage this atypical behavior," Forest and her colleagues wrote.

The takeaway of all this work is not to dump your Facebook account — the site has its benefits, some psychological. But researchers suggest being mindful about your online social life, just as most people are about friends in the real world.

"You have to be careful," said University of Houston psychologist Linda Acitelli, who advised Nguyen on the social comparison study. "I think parents, especially if they have teenage kids, need to be monitoring how much time they spend on Facebook."

Because Facebook provides more opportunities to peer into others' lives, it helps to keep Facebook pitfalls in mind, according to the Instituto de Empresa's Mukesh. She found that reminding people in the moment of what they already know ­— that people brag on Facebook — can ease the self-recriminations that come with hearing about friends' accomplishments.

"At the end of the day, have more friends, there's no problem with that. Just be sure to remember that when you start feeling crappy about your life, think about the fact that you have a large number of friends and that increases your probability of viewing more ostentatious information," Mukesh said. "So, it's not you, it's them."

More from LiveScience: 

• Top 10 Controversial Psychiatric Disorders
• 7 Thoughts That Are Bad For You
• That's an Order! 10 Privacy Tips from the Marines

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• All that stress is shrinking your brain, study finds
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Everyone knows stress can cause headaches and sleepless nights. But a new study suggests it can actually shrink your brain.

We’re not talking run-of-the-mill stressors here, like a looming deadline or a missed bus.

“These are bad things happening, like a relationship breakup, loss of a loved one, being held at gunpoint,” says Yale neurobiologist Rajita Sinha, senior author of the new report.

Simply feeling stressed-out was not linked to gray matter shrinkage. But feeling stressed-out combined with a history of stressful life events was.  In particular, stress was linked to markedly less gray matter than expected in a part of the prefrontal cortex that regulates emotion and self-control, not to mention blood pressure and blood sugar.

That shrinkage might serve as a red flag about a greater risk of chronic diseases such as high blood pressure as well as psychiatric disorders, according to the researchers. And maybe it’s already affecting brain function in the healthy individuals she studied, Sinha says.

In other words, the stresses of modern life are far more complicated than what our ancestors experienced. “You can say stresses are a part of life, so what’s the big deal?” Sinha says. But it is a big deal, she adds, because there’s extensive evidence that stress has contributed to the rise in chronic diseases.

Most human research about the impact of stress on brain structure has focused on patients with stress-related psychiatric disorders such as addiction and anxiety, according to the authors. Those studies have found decreased volume in the frontal lobe, considered the center of emotion control and personality.

But studies of the cumulative effects of stress on the brains of healthy people are rare, Sinha’s team writes in a paper published online this week in Biological Psychiatry.

The study enrolled 103 health adults ages 18 to 48. Researchers conducted structured interviews with the volunteers to collect information about stressful life events and subjective feelings of chronic stress.

The scientists then used MRI to scan the volunteers’ brains.

Whose brains shrunk more, men’s or women’s? You might think you know the answer, but the researchers don’t, because they didn’t have enough women to compare the sexes.

The take-home message, Sinha says, is that the better you cope with stress -- take a walk, call a friend -- the better off your brain will be.

More like this:

Men and women really do have big personality differences

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The strong resemblance of Kim Jong Un (right) to his popular grandfather Kim Il Sung (left) may be subliminally creating warm feelings among his followers.

Photographs show he has his grandfather’s double chin and dark eyebrows, and his haircut supposedly is a throwback to the older man’s style in the 1940s. Some reports speculate that Kim Jong Un has even undergone plastic surgery to make him look more like his popular grandfather, North Korea founder Kim Il Sung, and less like his father, Kim Jong Il, who was not as well-liked.

Whether the resemblance to his grandfather has been inherited and/or surgically enhanced, it sure can’t hurt Kim Jong-Un, his late father’s handpicked successor to lead North Korea, psychologist Robert Bornstein says.  He'll likely benefit from the experience many of us have had of feeling warmly toward a person we’ve just met  simply because they resemble someone we like.

“We tend to prefer things that seem familiar over the things that seem unfamiliar, all other things being equal,” says Bornstein, a psychology professor at Adelphi University in Garden City, N.Y. “People will prefer a familiar-looking face over one that is less familiar.”

Psychologists call this phenomenon “the mere-exposure effect,” as in the mere exposure to someone or something leads to liking him or it. “It’s actually very powerful,” says Bornstein, who’s been studying the mere-exposure effect ever since he wrote his dissertation on it in the 1980s.

There are 300 to 400 studies in the scientific literature about the phenomenon, mostly having to do with visual and auditory--“things like voices, accents, the cadence of a person’s voice”--characteristics. “If it rings a bell, then we do have this initial reflexive response to it,” Bornstein says.

In other words, when it comes to North Korea dictators, like grandfather, like grandson.

But can familiarity breed contempt as well as warm fuzzies? Maybe, Bornstein says, although there haven’t been nearly as many studies of that question. But some research suggests that if you meet someone who reminds you of, say, a hated boss, “you have sort of a negative gut reaction to them,” Bornstein says, “and it can be hard to overcome, partly because gut reactions are so powerful.”

Have you had a rush of affection for a stranger just because they look like someone you care about? Tell us on Facebook.

msnbc.com

Are you afraid of elevators?

Stories this week about shocking elevator deaths in New York -- including one in which a woman was crushed and killed and another in which a woman was attacked and set on fire -- horrified millions, but none as much as those who suffer from severe elevator phobias.

Such events are rare, but they rivet the attention of people who have trouble even riding an ordinary elevator to the next floor, sufferers and experts say.

"That was the first and maybe the only article I read in the New York Times," says Jane Murphy, a 52-year-old Dallas business owner, referring to the crushing accident. "It was horrible and I felt bad about her but in my mind it was just another confirmation as to why I don't like elevators."

Murphy says she's had her phobia for decades and can even remember walking up 14 flights of stairs to her family's condo as a teenager.

"I've even gone to meetings with clients and gotten them to open the door for me on the 10th floor since those doors are always locked," she says. "Sometimes I can force myself to ride one but other times, I can't step on. I don't have a choice. It feels like a do or die decision."

For Murphy, it's not so much a fear of dying in the elevator as a fear of getting trapped.

"I don't worry about tragedies, I worry about getting stuck," she says. "I think it's a control factor. It's all about being stuck in this sealed container."

According to Elizabeth Lombardo, a clinical psychologist who uses cognitive behavioral therapy to help people overcome fears, elevator phobias are relatively common (although not so common to be included on this comprehensive phobia list) and are definitely treatable.

"They're common and the reasons are twofold," says Lombardo, author of "A Happy You: Your Ultimate Prescription for Happiness." "One is the lack of control and the potential for death, i.e., the elevator is going to drop 20 stories and kill you and you have no control. The other component is claustrophobia because you're in a confined space. I have some clients who will only go in an elevator if there's only one person or no people in it. I've had clients not take jobs because they couldn't ride an elevator to their office."

Lombardo says the problem with elevator phobias is that it's actually possible for an elevator to suddenly drop a few floors or crush someone's limb -- or worse.

"When I was doing my pre-doctoral training down in Houston, there was a doctor who stuck his head into the elevator but not his legs and the sensors didn't go off and he was decapitated," she says. "Elevators can be dangerous and deadly. But so can vacuum cleaners. There are freak accidents everywhere."

What's important to remember, she says, is the difference between possibility and probability. The chance of a freak accident causing an elevator to malfunction or the chance of being attacked by a fire-wielding assailant are very small, of course, Lombardo said.

According to the New York Post, many New York office workers are already shunning elevators due to the accident. Will this week's tragedies have a bigger effect on those with elevator phobias?

"I will absolutely be getting more calls," says Lombardo. "For them, it's like, 'See? It really can happen. I'm justified in having this fear.'"

Murphy says that's certainly how she felt after reading this week's news.

"I got a vision in my mind about what kind of elevator it was," she says. "And could picture one of those old buildings in New York where the elevators have gold doors and they just look like such a barrier. That once you're in them you can never get out. And I just thought, 'Where's the stairs, man?'"

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The more attractive a man finds a woman, the better he thinks his chances are, according to the inexplicable findings of a new study.

Consider Howard Wolowitz and Rajesh Koothrappali.

They may be fictional characters on a popular sitcom, "The Big Bang Theory," but new research suggests there’s a lot of truth in how they interact with women.

Wolowitz is a teeny guy with dorky hair and dorky clothes. He’s brilliant and gainfully employed, but on the attractiveness scale, he’s maybe a 2, possibly a 2 ½. Despite his physical shortcomings, though, he imagines every hot woman who glances his way wants to jump his bones. Of course, he’s always wrong.

Then there’s his buddy Raj, a pretty nice-looking guy once you get past his haircut. But he’s so insecure around women he can’t even talk to them unless he’s drunk.

What’s the deal?

There are "tons" of studies that show men think women are interested when they’re not, says lead author Carin Perilloux, a visiting professor at Williams College. But her study, which will be published in an upcoming issue of Psychological Science, found that not all men do. And surprisingly, it appears that the dorky, less attractive guys are more likely to think they’re babe magnets than their more attractive counterparts.

Perilloux was an unattached graduate student at the University of Texas when she decided to look into how men perceive women’s level of sexual interest and vice versa. She and her coauthors enlisted the help of about 200 straight undergrads, split evenly between the sexes, with an average age just shy of 19.

The researchers asked each of their subjects to rate their own attractiveness on a scale of 1 to 7. The students then had three-minute one-on-one conversations with five members of the opposite sex, a setup the scientists describe as "speed meeting." (The goal wasn’t to get a date, because some of the participants already were involved with people outside the study.) After each conversation, they rated the other person’s attractiveness and sexual interest.

The more attractive the woman was to the guy, the more likely he was to overestimate her interest in him, researchers found. And it turns out, the less attractive men (who believed they were better looking than the women rated them) were more likely to think beautiful women were hot for them. But the more attractive guys tended to have a more realistic assessment.

And the women? Perilloux and her coauthors found that women underestimated men’s sexual interest.

Believe it or not, this all probably makes sense from an evolutionary perspective, the scientists say. Attractiveness is linked to fertility, so if guys keep hitting on hot women, they’re bound to score occasionally and father sons who act the same way. Those attractive men don’t have to try as hard. As for the women, their underestimation of guys’ sexual interest might help prevent them from developing a reputation as a slut

Of course, if men and women were more explicit about their level of interest, they wouldn’t be so confused, Perilloux points out. But it’s unlikely either sex is going to use the line "hey, I’m 75 percent interested in you."

So here’s Perilloux’s tips: "For men, the best piece of advice is to be more cautious if you’re interested in someone." For women, she says, save the flirting for guys you actually are interested in sleeping with. "Men seem to take any flirtatious signal and run with it."

Readers, this is basically the plot of some of the most frustrating rom-coms over the years. Which cinematic pairing did you find most unbelievable? Will Ferrell and Zooey Deschanel in "Elf"? Seth Rogan and Katherine Heigl in "Knocked Up"? Tell us on our Facebook page.

Read more Vitals! It's good for you.

Fight club: Most bar brawls begin on the dance floor

The scent of a man? It could be an STD

Woman's fake breast disappears during Pilates

featurepics.com

If you're the dance floor of a crowded bar - watch out for fisticuffs, says a new study.

By Cari Nierenberg

If you shake your booty on the dance floor of a crowded bar, you could be in for a world of hurt. And your lousy dance moves are not to blame. 

A recent study shows that the dance floor is the most likely place for fights to break out inside a large drinking establishment. The findings suggest that roughly 20 percent of the most harmful incidents took place on the floor itself; another 13 percent of them occurred near it.

The research, published in the journal Drug and Alcohol Review, looked at "hotspots" for aggression in bars and clubs.

In the study, researchers made more than 1,300 visits to 118 bars and clubs in Toronto over a two-year period. They went to bars that could hold more than 300 people, and they went on Fridays and Saturdays between midnight and 3 a.m.

Researchers observed the customers for aggressive behaviors, and they rated them on a scale of 1 (minor non-physical harm) to 5 (actions causing pain, including punching and kicking). They even gauged how intoxicated the customers seemed that night.

They found that the dance floor was the top spot for aggressive behavior. "There's a lot of sexual aggression and aggressive horseplay on the dance floor in late night, large-capacity bars and night clubs," says study author Kathryn Graham, a senior scientist at the Centre for Addiction and Mental Health in Toronto.

Sometimes it was just sheer numbers -- the dance floor was the most crowded place on the premises and this sparked more incidents. And partly it was because that's where the most rowdiness between dancers and even bystanders took place.

But Graham was a little surprised that the area at or near the serving bar was the second most common location for bad behavior. She figures this was mainly a traffic and congestion issue.

Tempers there could also flare between patrons and staff over drink service. And when hot heads get hammered, it can get ugly.

"I suspect that a lot of the aggression near the serving bar was in the form of male-to-male violence where egos are on the line when people get bumped," says Graham.

Then again, "It may also be that this is a good place to hang around if you're looking for trouble," she adds.

While the dance floor was the #1 hotspot for aggressive behavior and the space near the serving bar was second, the tables came in third. This was followed by the hallways, aisles, and stairs in fourth, the entrance was fifth, and the pool tables were sixth.

Although only 4 percent of incidents took place at pool tables, the area had a high rate of barroom brawls likely brought on by people's competitive juices mixing with alcohol.

So, when you head out for a night on the town, now you'll know the high-risk locations at your favorite watering hole. And feel free to pass along this research to the bar staff so they'll keep things from getting out of hand in these potential trouble spots.

The worst fights? They took place outside the bar, of course.

Talk about this story on Facebook.

Would-be lovers wondering whether to go forward with a new relationship might heed the advice of Russian scientists: Take a deep whiff.

Sniffing a potential partner’s scent could tell whether Mr. Right has a sexually transmitted disease, according to a small study that found that gonorrhea-infected men smelled “putrid” to a bevy of young ladies.

“Our research revealed that infection disease reduces odor attractiveness in humans …” wrote Mikhail Moshkin, a professor at the Institute of Cytology and Genetics in Novosibirsk, Russia, and the lead author of research published in the most recent issue of the Journal of Sexual Medicine.

The off-putting scent may be subtle, more a chemical warning than a blast of body odor, but it definitely has an effect, according to the experiment conducted by Moshkin and his colleagues.

The researchers had long observed that certain animals, such as mice and rats, were not as attracted to the scents of other critters when they were infected with disease. They wondered whether humans, too, would be turned off by the scent of an infected person, particularly one harboring an STD.

So they invited 34 strapping Russian guys, ages 17 to 25, to donate samples of armpit sweat and spit for the cause of science. The group included 13 young men with gonorrhea, 16 who were healthy and five who had had the disease but were successfully treated.

Then they found 18 female students aged 17 to 20 from Kemerovo State University in Russia who were willing to serve as sweat-sniffers.

They obtained sweat samples by dressing the men in tight-fitting T-shirts with cotton pads sewn into the armpits. After an hour of sweating, men bagged their shirts and the pads were placed in glass vials for the women to sniff.

The results couldn’t have been more obvious. The women ranked the infected men less than half as high as healthy or recovered guys on a “pleasantness score” that assessed scent.

And when they were asked to characterize the scent, the gals said that nearly 50 percent of the infected men’s sweat smelled “putrid." (To be fair, the gals also said that 30 percent of sweat from healthy men and less than 40 percent of sweat from treated men smelled putrid, but these are guys -- and it was significantly higher for the gonorrhea group.)

The take-away message, the researchers found, was that it appears that humans, like other animals, might use scent to sniff out appropriate mates.

“We can conclude that unpleasant body odor of infected persons can reduce the probability of a dangerous partnership,” the scientists say.

Heeding olfactory cures might not signal the right partner, but they could warn against the wrong one – unless, of course, the guy uses deodorant.

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Creativity may have a dark side.

The very same people who have the intellectual spark to think outside the box when solving complicated problems may also be the ones who can more easily indulge in cheating and general dishonesty, a new study suggests.

“Creative people are more able to come up with reasons to justify unethical behavior — they are more morally flexible,” said the study’s lead author Francesca Gino, an associate professor of business administration at the Harvard Business School. “Concluding that the rule does not make sense could be one of the potential justifications.”

To test the theory that people who score well in creativity may be more likely to cheat, Gino rounded up several groups of college students.

She and her co-author, Dan Ariely of Duke University -- who published their findings in the Journal of Personality and Social Psychology -- started out by testing study volunteers’ intelligence and creativity. Then the researchers ran a series of experiments that used money to tempt people into dishonesty.

In one experiment, the researchers gave volunteers a multiple-choice quiz that tested general knowledge. For every correct answer, the volunteers would make money.

The volunteers were later asked to copy their answers onto a special form.  One of the researchers told them that the correct answers had been lightly marked on these new forms -- by mistake -- and that they should ignore the marks, be honest, and fill out the forms as they had on their original quizzes. The volunteers were then told to discard their original quizzes, which didn’t have their names on them, in a special container.

In reality, the researchers had put special, identifying marks on the original quizzes. So they were able to compare the two versions to see if there had been any cheating. Sure enough, the researchers found that the most creative students were also the most dishonest. And that pattern held up in each of four other experiments.

While the study probably isn’t the last word on the subject, it may be a “cautionary tale,” said Art Caplan, director of the Center for Bioethics at the University of Pennsylvania and an msnbc.com contributor. “You’ve got to be careful in encouraging creativity since it probably comes with a potential for self-rationalization. Creative people will think of new ways to bend the rules to do what they want to do.”

Still, Caplan said, the researchers did load the dice in favor of their theory by choosing students for study volunteers.

“If I were trying to hunt up someone who is ethically the most willing to be pushing the limits, it would be college students,” Caplan explained. “They’re still exploring or testing ethics and morality."