8 Things We Learned About Human Nature in 2016
Does telling one lie make you more likely to tell another? During which season are couples most likely to divorce? And what prompts the victims of long-ago sexual assaults to finally speak out? This year, researchers have explored these questions and more, delivering fascinating insights into human nature. Here are eight of the most intriguing stories on human nature from this year.
Scientists discover human sociability genes
In a study that was published in the journal Nature in August, researchers identified some of the genes responsible for social behavior. The study involved people with Williams syndrome, a rare genetic disorder that makes people hypersociable, and that involves the deletion of a set of 25 genes on chromosome 7.
"I was fascinated on how a genetic defect — a tiny deletion in one of our chromosomes — could make us friendlier, more empathetic and more able to embrace our differences," Alysson Muotri, the study’s co-senior author and an associate professor of pediatrics and cellular and molecular medicine at UC San Diego School of Medicine, said when the study was published.
The researchers found that some neurons in the brains of those with Williams syndrome had increased branching, which might explain their gregarious nature. Muotri told Live Science that researchers still don't know why this enhanced connectivity is related to sociability — and not intelligence or memory.
Forcing a smile may not make you happier after all
Scientists may finally have disproved a landmark 1988 study that indicated that faking a smile could actually make people feel happier (or, at the least, make them rate cartoons as funnier). In the new work, which was published in October in the journal Perspectives on Psychological Science, a 17-lab effort that included 1,894 participants found no evidence for the so-called facial-feedback hypothesis. The facial-feedback hypothesis suggested that the body’s movements could affect mood, and not just the other way around.
However, the original researcher on the 1988 study, psychologist Fritz Strack of the University of Würzburg in Germany, argued that the replication study changed his original experiment to such an extent that it was no longer a faithful replication. "I’m not sure what we’ve learned other than the effect is not very strong," Strack told Live Science. [25 Scientific Tips for Raising Happy (& Healthy) Kids]
Lies may breed more lies
After you tell a lie, your brain may become desensitized to dishonesty, according to a study that was published in October in the journal Nature Neuroscience. In the study, researchers asked 80 adults to advise a second person about the amount of money in a glass jar that was full of pennies — and, in several trials, the participants were incentivized to lie. For example, the researchers promised them a higher reward if their partner overestimated the number of pennies in the jar.
When the researchers looked at the participants' brain activity, they observed patterns that suggested that the brain grows less sensitive to self-serving dishonest behavior.
"The study is the first empirical evidence that dishonest behavior escalates," Neil Garrett, the lead author of the study and an experimental psychology researcher at University College London, said at a news conference that was held at the time of the study's publication. Over time, the participants appeared to show "a reduced emotional response to these [dishonest] acts," Garrett said.
Why sexual assault victims wait to speak out
During the election, numerous women accused Donald Trump, now the President-elect, of sexual assault, leading some to wonder: Can we trust the allegations of those who waited so long to come forward? But Yolanda Moses, a professor of anthropology at the University of California, Riverside, and a consultant and trainer for preventing sexual harassment and sexual assault, said that just because women wait to come forward doesn’t mean that their stories are untrue.
In fact, she told Live Science, the blame society places on female victims for what happens to them may be one reason women don't speak out sooner. Women may also want to avoid the shame that might come with telling their story and the pain that comes with reliving their experience, Moses said. [5 Misconceptions About Sexual Assault]
How gender ratio affects marriage rates
Looking to get married? If you're a woman, you may have better luck if you live in a county with more men than women. In a studythat was published earlier this year, researchers examined U.S. Census data from 2,800 counties in all 50 states, looking at gender ratio, marriage rates and more. They found that in counties where men made up 55 percent of the population, the percentage of adults who were married was about 10 percent higher, on average, compared with counties where women were 55 percent of the population.
The study's lead author, Ryan Schacht, who is a postdoctoral researcher in anthropology at the University of Utah, said that the researchers suspect that this was because of what is termed the mating-market theory. "If you're the rarer sex, you have more bargaining power; you have greater leverage in terms of what you demand out of a partner," Schacht said.
Number of divorces may be affected by season
A 14-year study of divorce filings in Washington state showed that the rate of filings peaks twice a year — in March and in August. The researchers who conducted the study examined data from 2001 to 2015, and speculated that the pattern they found may be caused by troubled couples' hopes that they can fix their relationships during winter and summer holidays. The findings were published in August.
"People tend to face the holidays with rising expectations, despite what disappointment they might have had in years past," Julie Brines, an associate sociology professor at the University of Washington and one of the study’s co-authors, said when the study was published.
After the holidays, however, people may become disillusioned, and that may make them more likely to divorce. The reason for the delay after the holidays? The researchers said it might be that unhappy partners are getting their finances in order or gearing themselves up for the divorce before finally filing a few months later.
Cheating may be more likely at certain ages
People are twice as likely to cheat at the "danger age" of 39 than they are at other ages, a report in August suggested. The report also found that people are more likely to have affairs during the last years of other decades, such as at ages 29 or 49, than at other times.
Previously, a 2014 study from researchers at New York University and the University of California, Los Angeles, had found something similar, determining that users of an online dating site geared toward infidelity had a disproportionate number of adult users whose ages ended in the number 9 (29, 39, 49, etc.). The researchers in that study also surveyed the site users and found that those whose ages ended in 9 were also more likely to be preoccupied with aging, and to wonder whether their lives were meaningful.
Taking risks could be contagious
Risky behavior might be contagious, a small study that was published in March showed. In the study, 24 people faced a gambling scenario: They were given 4 seconds to decide whether they wanted a sure reward of $10 or a chance at getting a higher amount. Occasionally, they were asked to observe others who were faced with the same choice.
The scientists found that, when they were not watching other people, most participants behaved cautiously and chose the safe $10. But when they observed others engaging in risk-taking behavior, the participants were more likely to take the riskier bet.
"Our present findings indicate that when an individual has the opportunity to consistently observe the risky behavior of another agent, one's own risk-preference can be directly influenced," the scientists concluded.
Originally published on Live Science.
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