Love at First Sight?
by Frank Diller
American Scientist 91 no2 120-1 Mr/Ap 2003
Memo to our male readers: The world is full of cognitive dissonance and distractions--so when it comes to impressing the ladies, fellas, timing can be crucial. And yes, eye contact is important too. In fact, cultures that frown upon eye contact as sexually provocative may have a point.
Evolutionary psychologists have found evidence that ovulation heightens women's response to the pheromone androstenol--a contributor to male body odor--and to the sight of strong male facial features, ones that emphasize secondary sex characteristics, such as an angled chin or a large forehead. But the increased appeal of attributes conveying a sense of strength, aggression or dominance is only one part of the finely tuned mate-identification system.
C. Neil Macrae, a professor of psychological and brain sciences at Dartmouth College, and his colleagues theorized that women's heightened awareness of male features during certain phases of their menstrual cycle might be further demonstrated by subtle tests related to person perception--for instance, asking women to assign a gender to a face in a photograph or to a stereotypical term such as bald, doll or skirt.
Macrae's study, published in the November 2002 issue of Psychological Science, tested women during two different phases of their menstrual cycle: when the risk of conception was high (the day of ovulation and the two preceding days) and when the risk was low (the first three days of the cycle). Subjects were first asked to identify the gender of 100 randomly displayed faces in photographs (50 men and 50 women). In a subsequent test, women were asked to categorize the gender associated with 64 stereotypical terms. A randomly selected photograph of a man, a woman or a random pattern preceded each term as a priming stimulus. Participants were told to ignore the initial image (flashing on the screen for a fraction of a second and followed by a brief lull before the apearance of each term), but some women seemed extremely attuned to certain characteristics in the photographs.
The subjects' mean response times were fastest--both when identifying male faces and when categorizing typically masculine terms preceded by a male face--during the menstrual phase in which the women were at the highest risk of conception. Macrae and his colleagues conclude that proximity to ovulation may be one of many factors influencing the efficiency and access of social stereotypes.
Why use stereotypes to study sexual receptivity? Social stereotyping, Macrae says, "is basically a reservoir of knowledge and memory to access quickly ... and apply to situations when you don't have to think about them." Easy access to the mental shorthand of male characteristics might be particularly helpful when selecting a mate.
Previous research, Macrae says, shows that women also have an increased preference for "facial configurations that convey dominance" and other stereotypical male attributes. Women prefer more masculine faces during ovulation and more feminine faces at other points of the menstrual cycle. Men's notions of attractiveness (such as ideal hip-to-waist ratio), on the other hand, remain relatively constant over time.
Some factors that may influence access to social stereotypes seem to transcend gender. The mental shorthand involved in both genders' mate choices has been found to include a preference for symmetrical faces, an attribute that most people associate with such desirable traits as a strong immune system and general evolutionary fitness.
And in a study described in the September issue of Psychological Science, Macrae and his colleagues manipulated the eye gaze of faces in randomly displayed photographs. Among full-face and three-quarter-face images in which the eyes were looking straight ahead, averted or closed, both male and female subjects categorized the gender fastest when the photographed faces peered directly at them from the screen. A subsequent test, constituting the second part of the experiment, used the photographs as a priming stimulus for subjects distinguishing nonwords from stereotypical terms. In this situation the gaze direction in the photographs did not generally enhance test performance. (And in a study to be published in the March 2003 issue of the European journal Developmental Science--co-authored by Macrae and Bruce M. Hood of the University of Bristol--investigators report that children and adults more easily recognized and recalled faces with a direct gaze than an averted gaze.)
To identify important social interactions in daily life, Macrae says, "evolution forces you to tune the efficiency of the [perceptual] system." Awareness of this system can also provide keys to the impression we make on those around us: Your face may not be symmetrical, your timing not impeccable, but a direct look seems to send a strong signal to the opposite sex. Whether you actually impress someone when you open your mouth, however, is another matter entirely.