Incognito (15 page)

William James realized the hidden nature of instincts and suggested that we coax instincts into the light by a simple mental exercise: try to make the “natural seem strange” by asking “the why of any instinctive human act”:

Our most hardwired instincts have usually been left out of the spotlight of inquiry as psychologists have instead sought to understand
uniquely human acts (such as higher cognition) or how things go wrong (such as mental disorders). But the most automatic, effortless acts—those that require the most specialized and complex
neural circuitry—have been in front of us all along: sexual attraction, fearing the dark, empathizing, arguing, becoming jealous, seeking fairness, finding solutions, avoiding incest, recognizing facial expressions. The vast networks of neurons underpinning these acts are so well tuned that we fail to be aware of their normal operation. And just as it was for the chicken sexers,
introspection is useless for accessing programs burned into the circuitry. Our conscious assessment of an activity as easy or natural can lead us to grossly underestimate the complexity of the circuits that make it possible. Easy things are hard: most of what we take for granted is neurally complex.

As one illustration of this, consider what has happened in the field of
artificial intelligence. In the 1960s it made rapid progress in programs that could deal with fact-driven knowledge, such as “a horse is a type of mammal.” But then the field slowed almost to a halt. It turned out to be much more difficult to crack “simple” problems, such as walking along a sidewalk without falling off the curb, remembering where the cafeteria is, balancing a tall body on two tiny feet, recognizing a friend, or understanding a joke. The things we do rapidly, efficiently, and unconsciously are so difficult to model that they remain unsolved problems.

The more obvious and effortless something seems, the more we need to suspect that it seems that way only because of the massive circuitry living behind it. As we saw in
Chapter 2
, the act of seeing is so easy and rapid precisely because it is underpinned by complicated, dedicated machinery. The more natural and effortless something
seems
, the less so it
is
.
²¹
Our lust circuits are not driven by the naked frog because we cannot mate with frogs and they have little to do with our genetic future. On the other hand, as we saw in the first chapter, we
do
care quite a bit about the dilation of a woman’s eyes, because this broadcasts important information about sexual interest. We live inside the umwelt of our instincts,
and we typically have as little perception of them as the fish does of its water.

Why are people attracted to young mates and not to the elderly? Do blondes really have more fun? Why does a briefly glimpsed person appear more attractive than a person at whom we’ve taken a good look? At this point, you won’t be surprised to find that our sense of beauty is burned deeply (and inaccessibly) into the brain—all with the purpose of accomplishing something biologically useful.

Let’s return to thinking about the most beautiful person you know. Well-proportioned, effortlessly well liked, magnetic. Our brains are exquisitely honed to pick up on those looks. Simply because of small details of symmetry and structure, that person enjoys a destiny of greater popularity, faster promotions, and a more successful career.

At this point it will not surprise you to discover that our sense of attraction is not something ethereal—properly studied only by the pens of poets—but instead results from specific signals that plug, like a key into a lock, into dedicated neural software.

What people select as beautiful qualities primarily reflect signs of
fertility brought on by hormonal changes. Until puberty the faces and body shapes of boys and girls are similar. The rise in
estrogen in pubescent girls gives them fuller lips, while
testosterone in boys produces a more prominent chin, a larger nose, and a fuller jaw. Estrogen causes the growth of the breasts and buttocks, while testosterone encourages the growth of muscles and broad shoulders. So for a female, full lips, full buttocks, and a narrow waist broadcast a clear message:
I’m full of estrogen and fertile
. For a male, it’s the full jaw, stubble, and broad chest. This is what we are programmed to find beautiful. Form reflects function.

Our programs are so ingrained that there is little variation across
the population. Researchers (as well as purveyors of pornography) have been able to discern a surprisingly narrow range for the female proportions that males find most attractive: the perfect ratio between the waist and hips usually resides between 0.67 and 0.8. The waist-to-hip ratios of
Playboy
centerfolds has remained at about 0.7 over time, even as their average weight has decreased.
²²
Women with a ratio in this range are not only judged by males as more attractive, but are also presumed to be more healthy, humorous, and intelligent.
²³
As women become older, their features change in ways that depart from these proportions. Middles thicken, lips thin, breasts sag, and so on, all of which broadcast the signal that they are past peak fertility. Even a male teenager with no biology education will be less attracted to an elderly woman than to a young woman. His circuits have a clear mission (reproduction); his conscious mind receives only the need-to-know headline (“She is attractive, pursue her!”) and nothing more.

And the hidden neural programs detect more than fertility. Not all fertile women are equally healthy, and therefore they do not all appear equally attractive. The neuroscientist
Vilayanur Ramachandran speculates that the quip about men preferring blondes may have a biological seed of truth to it: paler women more easily show signs of disease, while the darker complexions of swarthier women can better disguise their imperfections. More health information allows a better choice, and thus is preferable.
²⁴

Males are often more visually driven than females, but women are nonetheless subject to the same internal forces; they are drawn by the attractive features that flag the maturity of manhood. An interesting twist is that a woman’s preferences can change depending on the time of month: women prefer masculine-looking men when they are ovulating, but when not ovulating they prefer softer features—which presumably flag more social and caring behavior.
²⁵

Although the programs of seduction and pursuit run largely under the machinery of consciousness, the endgame becomes obvious to everyone. This is why thousands of citizens of rich countries shell out for face-lifts, tummy tucks, implants, liposuction,
and Botox. They are working to maintain the keys that unlock the programs in other people’s brains.

Not surprisingly, we have almost no direct access to the mechanics of our attractions. Instead, visual information plugs into ancient neural modules that drive our behavior. Recall the experiment in the first chapter: when men ranked the beauty of women’s faces, they found the women with dilated eyes more attractive, because dilated eyes signal sexual interest. But the men had no conscious access to their decision-making processes.

In a study in my laboratory, participants viewed brief flashes of photographs of men and women and rated their attractiveness.
²⁶
In a later round they were asked to rate the same photos they had seen before, but this time with as much time as they wanted to examine the photos. The result? Briefly glimpsed people are more beautiful. In other words, if you catch a glimpse of someone rounding a corner or driving past quickly, your perceptual system will tell you they are more beautiful than you would otherwise judge them to be. Men show this misjudgment effect more strongly than women, presumably because men are more visual in assessing attraction. This “glimpse effect” accords with everyday experience, in which a man catches a brief glimpse of a woman and believes he has just missed a rare beauty; then, when he rushes around the corner, he discovers that he was mistaken. The effect is clear, but the reason behind it is not. Why should the visual system, given just a bit of fleeting information, always err on the side of believing that the woman is more beautiful? In the absence of clear data, why wouldn’t your perceptual system simply strike for the middle and judge the woman to be average, or even below average?

The answer pivots on the demands of reproduction. If you believe a briefly glimpsed unattractive person is beautiful, it requires only a double take to correct the mistake—not much of a cost. On the other hand, if you mistake an attractive mate for an unattractive one, you can say
sayonara
to a potentially rosy genetic future. So it behooves a perceptual system to serve up the fish tale that a briefly glimpsed person is attractive. As with the other examples,
all your conscious brain knows is that you just passed an incredible beauty driving the other way in traffic; you have no access to the neural machinery nor to the evolutionary pressures that manufactured the belief for you.

Concepts learned from experience can also take advantage of these hardwired mechanisms of attraction. In a recent study, researchers tested whether being unconsciously primed for the concept of alcohol would (also unconsciously) tickle the concepts associated with alcohol, such as sex and sexual desire.
²⁷
Men were shown words like
beer
or
bean
—but the words were flashed too rapidly to be consciously perceived. The men then rated the attractiveness of photographs of women. After being unconsciously primed with the alcohol-related words (like
beer
), the subjects rated the photographs as more attractive. And the males who more strongly believed that alcohol increases sexual desire showed the strongest effect.

Attraction is not a fixed concept, but instead adjusts according to the demands of the situation—take, for example, the concept of being in heat. Almost all female mammals give off clear signals when they are in heat. The rear end of female baboons turns bright pink, an unmistakable and irresistible invitation for a lucky male baboon. Human females, on the other hand, are unique in that they participate in mating year-round. They do not broadcast any special signal to publicize when they are fertile.
²⁸

Or don’t they? It turns out that a woman is considered to be most beautiful just at the peak of
fertility in her menstrual cycle—about ten days before menses.
²⁹
This is true whether she’s judged by men or by women, and it’s not a matter of the way she acts: it is perceived even by those looking at her photographs. So her good looks broadcast her level of fertility. Her signals are subtler than the baboon’s rear end, but they only need to be clear enough to tickle the dedicated, unconscious machinery of the males in the room. If they can reach those circuits, the mission is accomplished. They also reach the circuitry of other females: women are quite sensitive to the effect of other women’s cycles, perhaps because this lets them assess their competitors when fighting for mates. It
is not yet clear what the tip-offs for fertility are—they may include some quality of the skin (as tone becomes lighter during ovulation) or the fact that a woman’s ears and breasts become more symmetrical in the days leading up to ovulation.
³⁰
Whatever the constellation of clues, our brains are engineered to latch on, even while the conscious mind has no access. The mind merely senses the almighty and inexplicable tug of
desire.

The effects of ovulation and beauty are not just assessed in the laboratory—they are measurable in real-life situations. A recent study by scientists in New Mexico counted up the tips made by lap dancers at local strip clubs and correlated this with the menstrual cycles of the dancers.
³¹
During peak fertility, dancers raked in an average of $68 an hour. When they were menstruating, they earned only about $35. In between, they averaged $52. Although these women were presumably acting in a high capacity of flirtation throughout the month, their change in fertility was broadcast to hopeful customers by changes in body odor, skin, waist-to-hip ratio, and likely their own confidence as well. Interestingly, strippers on birth control did not show any clear peak in performance, and earned only a monthly average of $37 per hour (versus an average of $53 per hour for strippers not on birth control). Presumably they earned less because the pill leads to hormonal changes (and cues) indicative of early pregnancy, and the dancers were thus less interesting to Casanovas in the gentlemen’s clubs.