Sex science

Birds do it.

Bees do it.

But why do we fall in love? How do we stay in love? What do we gain from love?

To explore those questions and more, the Wisconsin Gazette poured some wine, unwrapped a box of truffles, lit a candle and delved into a year’s worth of science and health journals.

Jesse Hollister and colleagues at the University of Toronto were captivated by the elegant, showy evening primrose because 30 percent of the species in the genus have evolved to reproduce asexually. This made the primrose the right plant to test a theory that biologists have long promoted: Species that reproduce sexually are healthier over time than species that reproduce asexually, because they don't accumulate harmful mutations.

The researchers, working with teams in Canada and China, examined 30 pairs of the primrose species. One in the pair reproduced asexually; the other sexually.

“What we found was exactly what we predicted based on theory,” Hollister stated.

“This is the first genetic support for the theory that a significant cost to being asexual is an accumulation of deleterious mutations,” said University of Toronto professor Mark Johnson. “This study has allowed us to unlock part of the mystery of why sex is so common. It’s good for your health, at least if you are a plant.”

Falling in love really does make the heart go pitter-patter and takes one's breath away, say scientists with the Loyola Sexual Wellness Clinic at Loyola University's Stritch School of Medicine in Chicago.

Clinic co-director Pat Mumby said falling in love releases a flood of feel-good chemicals—dopamine, adrenaline and norepinephrine.

“This internal elixir of love is responsible for making our cheeks flush, our palms sweat, and our hearts race,” said Mumby.

Credit dopamine for that euphoric feeling.

Credit adrenaline and norepinephrine for that pitter-patter of the heart and the pre-occupation with that other person.

Think you remember the details of a love at first sight?

Maybe.

Maybe not, according to research from Northwestern University that was conducted with the support of the National Institutes of Health and published in the Journal of Neuroscience.

The researchers showed that fragments of the present get inserted into the past to form faulty memories. Memories get adapted and updated, reframed to fit the now, according to lead author Donna Jo Bridge, who led the research at the Northwestern University Feinberg School of Medicine.

For the study, people viewed object locations on a computer screen with varied backgrounds. When asked to place the objects in the original location, the participants always placed them incorrectly. Next participants were shown the objects in three locations on the original screen and asked to choose the correct location. They placed the objects in the misremembered location because they had reformed the memory.

Researchers with the University of Chicago, working with the University of Geneva, analyzed the eye movements of test subjects studying black-and-white photographs of strangers.

They found that people tended to fixate on the face, especially when they said an image elicited a feeling of romantic love.

However, subjects’ eyes moved from the face to the rest of the body when images evoked sexual desire.

Professors with the Weinberg College of Arts and Sciences and the Kellogg School of Management at Northwestern University in Evanston, Illinois, examined changing expectations of marriage and relationships—from the 18th century to the 21st.

They reported that Americans, on average, are making smaller investments of time and energy in their relationships than in the past and they have very different expectations from the couples of yesterdays.

“In 1800, the idea of marrying for love was ludicrous,” stated psychology professor Eli Finkel, the lead author of a paper presented at the American Association for the Advancement of Science annual meeting in Chicago. “That isn’t to say that people didn’t want love from their marriage; it just wasn’t the point of marriage.”

Today, according to Finkel, “Americans look to their marriages to help them ’find themselves’ and to pursue careers and other activities that facilitate the expression of their core self.”

A study presented at the Society for Personality and Social Psychology annual conference in Austin, Texas, this past year suggested that double dating can help spark romance for a couple—provided the double date involves deep, revealing conversation.

Passion can decrease for a couple over time, but research shows that self-disclosure in a couple affects closeness and passion.

So what happens when two couples form a fast friendship and go beyond small talk to discuss deeper, personal topics?

“The more that the other couple responds to your self-disclosures in a validating and caring way when on a double date, the more passionate you feel about your own relationship,” said study author Keith Welker of Michigan’s Wayne State University. “Although we still need to investigate why responsiveness from other couples predicts increases in passionate love, one possibility is that having another couple respond positively to yourself and your partner may provide you with a fresh, positive view of your partner and relationship.”

A caution: Be sure that other couple is going to make you look good before you book a table for four on Valentine’s Day.

A study from the University de Porto in Portugal published in Applied Research in Quality of Life indicates that people of faith and regular churchgoers are positive about their love lives and tend to express greater satisfaction with life and sexual relationships than the average adult.

The research involved nearly 1,300 Portuguese adults between 18 and 90 years old and used the “Satisfaction With Love Life Scale.”

For her study on sexual pleasure, Penn State sociologist Beth Montemurro conducted a series of interviews with heterosexual women between the ages of 20 and 68.

Most women in the study said being in love made sex physically more pleasurable. Women in love said they felt less inhibited and more willing to explore.

Montemurro said the women interviewed “seemed to say you need love in sex and you need sex in marriage.”

A team at Indiana University looked at attitudes toward couples and found that people generally think of loving relationships in a hierarchy: heterosexual couples being the most “in love,” followed by lesbian couples and then gay couples.

And these attitudes, the IU researchers wrote, led people to form beliefs about who should enjoy what rights and liberties—from holding hands to legally marrying.

The paper was titled “(Double) Standards for Granting Formal and Informal Privileges.”

Nearly all the gay and bisexual men involved in a first-of-its-kind study on love and sex said their most recent sexual event occurred with a relationship partner and that they felt “matched” in feelings of love with that partner.

The study, “Sexual Health in Gay and Bisexual Partners” was published in the Archives of Sexual Behavior and conducted by Virginia’s George Mason University Department of Global and Community Health and the Indiana University Center for Sexual Health and Promotion.

“These findings highlight the prevalence and value of loving feelings within same-sex relationships,” Joshua G. Rosenberger, lead investigator and George Mason professor, said when releasing the research.

The study was based on an Internet survey of 25,000 men.

“Very few people had sex with someone they loved if that person didn’t love them back,” said research scientist Beth Herbenick. “This ’matching’ aspect of love has not been well explored in previous research, regardless of sexual orientation.”

Cheating—is it worse to think about it than to do it?

Well, researchers of a newly published study report that heterosexual men are likelier than heterosexual women to be upset by sexual infidelity—54 percent of heterosexual men, 35 percent of heterosexual women.

However, heterosexual men are less likely than heterosexual women to be upset most by emotional infidelity—46 percent of heterosexual men, 65 percent of heterosexual women.

Bisexual men and women, gays and lesbians did not differ significantly.

“Heterosexual men really stand out from all the other groups: They were the only ones who were much more likely to be upset by sexual infidelity rather than emotional infidelity,” stated lead author David Frederick, who suggested insecurity about paternity may have something to do with the emotions.

The study was conducted by Chapman University in California and involved a survey of about 64,000 people.

Psychologists at the German Universities of Jena and Kassel reported last fall that a romantic relationship helps neurotic people find stability.

The researchers interviewed 245 couples several times over nine months. Using a questionnaire, the researchers gauged changing degrees of neuroticism and relationship satisfaction. Participants also were asked about fictitious everyday life situations and their possible significance for their own partnership.

“This part was crucial, because neurotic people process influences from the outside world differently,” study author Christine Finn stated, noting that neurotic people react more strongly to negative stimuli and have a tendency to interpret ambiguous situations negatively.

The researchers found that over time, neurotic tendencies decrease as a romantic relationship builds.

Finn stated, “The positive experiences and emotions gained by having a partner change the personality—not directly but indirectly—as at the same time the thought structures and the perception of presumably negative situations change.”

A report in the journal PNAS indicated that computer models might know a person's personality as well as his or her significant other.

Researchers at the University of Cambridge and Stanford University said a computer model using a person’s likes on Facebook can predict a person’s personality more accurately than most friends and family and well enough to rival the judgment of a partner.

In the study, the computer more accurately predicted a person’s personality than a work colleague based on just 10 likes, more than a friend based on 70 likes, better than a parent or sibling with 150 likes and as well as a spouse with 300 likes.

“People may choose to augment their own intuitions and judgments with this kind of data analysis when making important life decisions, such as choosing activities, career paths or even romantic partners,” said lead author Wu Youyou of Cambridge’s Psychometrics Centre. “Such data-driven decisions may well improve people’s lives.”