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If there were a Pantheon of developmental psychologists, scientists who changed the way we study and understand human development, Esther Thelen (1941-2004) would take her her place there, alongside the likes of Harry F. Harlow, Mary Ainsworth, John Bowlby, Leta Stetter Hollingworth and many others. Let me acknowledge that she didn't work on gender. But what she has to say about that dynamic system we call infancy, if applied to the study of sex and gender differentiation, will move us toward better understandings and away from the stale old debates about nature and nurture.
Thelen studied motor development. When she came on the scene, most psychologists thought that infants become more coordinated over time because as babies grow, the brain more or less spontaneously matures. Just add food and wait. Soon the child will be grasping, and coordinating limbs and then stepping and walking. It was kind of the chia pet theory of child development: add water and watch the greenery grow.
Thelen was that rare Avis scienticus who combined brilliant experiments with powerful theory. In one early study she tethered the left ankle of three-month-olds to a mobile. As they kicked spontaneously, the moving mobile excited them and they kicked all the more. Sometimes she yoked both feet together with a soft elastic which allowed the babies to kick one leg, alternate kicks, or kick both legs together. Kicking together gave the most mobile bang for the buck. While all of the babies kicked more and faster when they got the mobile reinforcement, only the yoked kids moved their legs together, in phase, in a manner previously thought impossible for three month olds, because their brain (supposedly) had not yet sufficiently matured.
Thelen concluded that three month olds could learn coordination tasks, and that specific experiences such as the ones she engineered, actually led to the development of motor skills. That is, what had previously been understood as autonomous brain maturation, was really the brain's response to physical experience. It was a dynamic developmental system. Thelen applied her ideas in a wide variety of experimental situations-learning to reach in a directed fashion, learning to walk and most notably, learning to think.
In rethinking thinking, Thelen took on Jean Piaget--another Pantheon member, who believed that on our journey to adulthood we acquire abstract and formal thought processes that detach from our motor and sensory perceptions. In contrast, Thelen argued forcefully-and to me persuasively-that humans ground mental activity "in continually perceiving the world and activity in it, not just in the initial state but throughout life". In her Presidential address to the Society for Research in Child Development, Thelen described how we might acquire skills via an embedded system-the nervous system interacting with the rest of the body which interacts with the world outside the body; for examples from the animal world think back to those mother mice that licked males more than females, or those ducklings hearing themselves quack (link to those blog entries).
In Thelen's view behavior emerges as a pattern from all the streams that flow into the river of infant development. Or, as she wrote "The mind simply does not exist as something decoupled from the body and experience". But what does all this have to do with gender? First, gender is a developing set of beliefs about oneself; it is also a set of behaviors that usually match the gender beliefs and a set of skills a child uses to recognize and respond to gender in others. For gender wonks, the question is: how do the elements of gender knit into an apparently seamless system? I can think of no better framework than Thelen's with which to build a theory of gender development.
A few researchers have explicitly applied the Thelen approach to the study of gender. I will close this entry with a brief discussion of the work of Carol Martin and her colleagues. Martin (when I write "Martin" I always mean her and her accomplished research team) starts from a well established observation: between 2.5 and 3 years girls start to prefer to play with other girls and boys with boys. This strong preference for same-sex play partners is widespread. Furthermore, same sex play becomes part of a feedback loop that generates more girlishness and boyishness as girls are exposed more to other girls and their preferences and play styles, and boys to boys. But where does it come from? Does it appear only in certain contexts? What, in short, is the geo-social organization of such peer play?
Same-sex playing children
Martin observed playground interactions for a number of boys and girls, considering gender alongside certain personality traits. Using a special way of mapping each step in a 10 second period, they followed how long each child contacted, stayed with and moved away from children of different sex and different character traits. For example, socially competent children attracted playmates from both sexes. But externalizing boys (who direct emotions outward) preferred other externalizing boys, but not externalizing girls. Internalizing girls (who direct emotions internally) interacted more with competent girls and externalizing boys than other children, but seldom with externalizing girls. In other words, patterns of preference varied in complex ways. Varying combinations of gender, personality and capability produced patterns of playground playmate preference. Martin suggests that we should think beyond the idea of two cultures-the boy and the girl culture and consider that there are multiple types of socialization spheres in preschool-which they call microcultures.
In one last example Martin found two long term play patterns-children who, over several months interacted more with same sex peers than other sex playmates. When they compared these two groups, they found that kids who were more strongly attracted to same-sex playmates had more restricted emotional ranges than ones who were more balanced in gendered play patterns. Same sex playing kids are emotionally more constrained and other-sex playing kids seem to tolerate a wider range of emotions in their playmates.
Other sex playing children
Beyond simply documenting difference we can now explore the dynamics of how difference emerges and maintains itself. Thelen gave us the critical theory. Martin (and others) are starting to apply the theory to the emergence of gender. Stay tuned. Things are just starting to get interesting.
