Why Men Want Sex and Women Need Love (5 page)

In summary, the science shows entirely different processes are being used to evaluate the opposite sex during early love—men use their eyes as the primary tool to evaluate women for sexual potential, and women use memory to assess a man’s characteristics for potential as a long-term partner. Lust and love have different locations in the brain and are
not
the same thing.

When Bartels and Zeki showed images of attractive women to men, they found that men showed higher activity in two regions in the brain: one associated with visual stimuli and the other with penile erection (gee, who would have guessed!). The majority of men are highly visual and constantly watch women, fantasize about them, and love to look at porn, so this is no surprise to most of us. When these areas in men’s brains are lit up, the researchers found that the men’s brain areas linked to making moral judgments also diminish in activity.

The visual brain network in men evolved over the last million years because men needed to look at women to size up their ability to produce healthy babies to keep the species going. If a woman was young and healthy, a man would become aroused and start the mating process. This is why men fall in love faster than women—they are more visually motivated, and visual cues are immediate and send a signal to the brain that activates an instant hormone surge. It also helps explain why men are more likely than women to fall in love at first sight.

In essence, men use their eyes primarily for evaluating the potential of a woman. When men are turned on, they become flushed with hormones and have erections. These hormones can overtake rational thinking, and therefore men can make decisions that may not be in their own best interests. It becomes a situation where his erections override his brain. This is hardly a shock to any woman who has had experience with men. These scans corroborate the research by David Buss showing that these behaviors are a universal, cross-cultural phenomenon.

Studies of women’s brain scans revealed something very different from the men’s scans. In women, several brain areas associated with memory recall became active when evaluating men for attractiveness. In evolutionary terms, this is an adaptive strategy to remember all the details of a man’s behavior.

For hundreds of thousands of years, women have had the job of raising babies to a stage of independence. Motherhood is a complex job, and it is harder for human females than for
any other mammal. Human mothers need support and protection when feeding and caring for their offspring. In prehistoric times, if a woman’s partner died, she’d need to expend an enormous amount of energy to find a replacement. Unlike a man’s immediate visual approach to evaluating the opposite sex, it’s not possible for a woman just to look at a man and know whether he’s honest and trustworthy, whether he can hit a moving zebra with a rock from fifty meters, or if he’ll share the meat with her. The same evaluative process is used by a woman today to be able to remember things such as what a man said yesterday, what he said three weeks or three months ago, how he reacts to children, whether he is kind and generous, how he treats his mother, his employment history, and his assets, and she’ll use all of this to evaluate his potential as a partner. When a woman studies images of one man, she recalls other men she knows who have similar features and then recalls their personality traits. Her brain then decodes the traits that correspond to the face of the man she’s looking at. It’s as though she is putting together a mental jigsaw of one man’s character by using a database of pieces of many other men. This doesn’t mean she gets it right; it means that she constructs a mental composite based on the men she knows. While women’s brains are recalling data about many men to assess a man’s potential as a partner, men just take long, hard, and many obvious looks at women. Now you know why women never forget and men are always being caught ogling women.

Donatella Marazziti, a psychiatrist at the University of Pisa, Italy, investigated the hormonal changes connected to obsessive-compulsive disorder (OCD) with a focus on serotonin, the chemical that has a soothing effect on the brain. Too little serotonin has been linked to aggression, obsession, depression, and anxiety. Drugs in the Prozac family fight these conditions by boosting the chemical’s presence in the brain. Marazziti was intrigued by how both people with OCD and love-struck individuals can spend hours fixating on a certain object or that certain someone and how both groups often know their obsession is irrational but seem to have no control over it. She measured the serotonin levels of twenty OCD sufferers against twenty “madly-in-love” people. She then compared the results against another twenty people who were not affected by OCD and were not in love. While the “normal” subjects had the normal level of serotonin, both the OCD and in-love participants had about 40% less of the chemical. The way the scientists estimate this is by the amount of activity of a serotonin transporter protein in their blood platelets. This experiment can explain how early romantic love can often turn into obsession.

Retesting the same subjects twelve to twenty-four months later, Marazziti found that the hormonal differences of lust had disappeared entirely, and their serotonin levels were back to normal, even if the couples were still together. Lovers will swear to each other that they will always “feel” this way, but their hormones clearly tell a different story. Mother Nature is very clever: She adjusts our hormone levels for just long enough to drive us to achieve her evolutionary goal—to produce offspring.

Using the same method for volunteer selection, in 2005 Enzo Emanuele and his colleagues at the University of Pavia, Italy, investigated whether the chemical messengers, the neurotrophins, are involved in romantic love. They reported that the concentration of nerve-growth factor in the blood exceeds
normal levels in infatuated volunteers and that it increases with the intensity of romantic feelings. Like Marazziti, Emanuele and colleagues also found that after one to two years, all of the love chemicals had gone, even if the couples were still together. Neither the initial intensity of the love feelings nor the concentration of nerve-growth factor appeared to be an indicator of whether a relationship would last.

Interestingly, a study released in 2008 by a team from Stony Brook University in New York, headed by Dr. Arthur Aron, scanned the brains of couples who had been together for 20 years and compared them with those of new romantic lovers. They found that about 10% of the mature couples demonstrated the same brain activation and chemical reactions when shown photographs of their loved ones as the “new” lovers did. So there is hope for some of us.

Meanwhile, at Whitchurch Hospital in Cardiff, Wales, biochemist Abdulla Badawy has shown that alcohol also depletes serotonin in the brain. Low levels of serotonin dissolve inhibitions and create an illusion that the ordinary-looking person at the other end of the bar is unbelievably attractive.

All this research shouts a clear message to those looking for long-term love: Wait for up to two years before making a long-term emotional or financial commitment to someone—and choose your bars carefully.

But if all the chemical messengers of intense romantic feelings disappear within two years, what is the chemical glue that keeps some couples together for the long term? All is not lost—we’ll discuss this in later chapters.

One reason new love is so heart-stopping is the possibility and fear that the feeling may not be entirely reciprocal and that the dream could suddenly end.

In another experiment, Drs. Fisher, Brown, and Aron carried out brain scans on forty young men and women who were recently dumped by their lovers. As in the “newly-in-love” study in 2007 by Brown and Fisher, the researchers compared two sets of images: one taken when the participants were looking at a photo of a friend, the other when looking at a picture of their ex. The results showed that when you look at a photo of someone who has just abandoned you, the brain areas associated with physical pain, obsessive-compulsive behavior, risk taking, and controlling anger all switch on. They also found that when you get dumped, these brain areas usually light up even more and you become even more attracted to your rejecting partner. As a coping mechanism—similar to the “fight-or-flight” response—your brain gears up for at least one more attempt to recapture your lover’s attention to avoid the pain of being hurt. When, however, you finally accept that you have been abandoned and you come out of denial, the brain areas connected with despair light up.

When the participants in the studies viewed their former lovers’ pictures, it also triggered the dopamine system in the brain—the same system associated with pleasure and addiction. This did not happen when they viewed images of their friends. The brain images of those who were dumped also explain why the breakdown of a relationship can trigger serious health problems. When someone is past denial and the
happiness hormones such as dopamine disappear, they are replaced with chemicals that can lead to depression and can reduce the body’s immune system, triggering illness. The rule of thumb is that it takes about a month for every year of a past relationship for you to emotionally “get it out of your system” and for your hormones to return to their normal stress-free, healthy levels. So if a relationship lasted for, say, two years, it would take two months to get it out of your system and for you to feel you are over it. This explains why elderly people who lose a partner after fifty years of marriage may never recover from what is commonly known as a “broken heart.”

In basic terms, sex drive is the result of a cocktail of chemicals released into the blood by the brain, which stimulates the production of hormones, primarily testosterone and estrogen. The circumstances you are under at the time can also trigger the brain to release these chemicals. For example, a particular song, a special smell, or a person who has certain physical features can trigger the chemical release. As we age, these hormone levels, particularly of testosterone, decrease. Testosterone injections have become common for older men and women with declining sex drives. We will discuss this more later, but it is important to understand that all romantic ideals, love feelings, and the highs and lows you may experience in new love are chemically linked and are not the mysterious, mystical meeting of souls that many people like to believe.

Science is at last revealing things about romantic love, lust, sex, and attachment that have been shrouded in mystery and fantasy for thousands of years. This science is like a GPS for love in the brain. Some people become alarmed about this and say that this type of research removes the wonder and excitement of new love and romance. In fact, it does the opposite. By understanding why you are motivated to make the choices you make and by understanding that love has a scientific and
biological basis and is not a mystical force, you can better control your choices and improve your odds in the mating game in spite of the fact that your brain is hardwired the way it is. Instead of claiming, “My hormones made me do it,” you can take control of the wheel and decide where you’d like to drive. In addition to your biology, other forces are also at play, and you have significant control over these, which is what you will discover in the rest of this book.

When the first car GPS was introduced by BMW, some people protested that it took the fun out of driving and discovering new places. In fact, what the GPS really did was to stop people from becoming frustrated and angry, spending time pointlessly in dead-end roads, or driving down the wrong roads. It can be fun to be lost sometimes, but with new technology, you always have a backup plan in your pocket or purse, and that’s what’s coming in the next chapters.