"It's going to be hard to answer the nature or nurture question definitively because it's a complex question. Research gives us insights into gender differences that may be biological but this question is also political. The bottom line is that sixty years after the birth of the women's movement, America ranks 37th in the world in terms of female leadership (behind Ethiopia). Why are we even asking the question, could our country have a female president? It's not just because girls are afraid and have less chemical drive that we don't have a greater percentage of female political leaders. Until we acknowledge that there is enormous prejudice, and women are not allowed to have the same economic and political status as men, we can't fully answer the nature or nurture question."
Catherine Steiner-Adair, Ed.D.
Lisa Sjostrom, Ed.M.
Co-authors, Full of Ourselves: A Wellness Program to Advance Girl Power, Health and Leadership
Recent research about the brain has in fact found subtle but significant differences between male and female brains. Among the findings:
Gender-specific wiring can be found in about 80 percent of children's brains. Interestingly, the remaining 20 percent have wiring that is more typical of the opposite gender — a finding that has nothing to do with sexual orientation, but which may affect a child's interests and abilities.
Differences begin before birth.
JoAnn Deak reports that the differences in male and female brains start in the womb. "Many female brains have more neurons in certain areas than male brains, as a result of having more estrogen bathe them during fetal development. A hormonal/chemical wash (estrogen for girls, testosterone for boys) actually enhances certain parts of the brain and changes them structurally before birth. Therefore, each of us is born with different hard wiring."
Girls' brains develop at a different pace.
Girls and boys appear to have different developmental timelines, due in part to the differences in their brains. "For example," Deak notes, "most girls are born with language processing neurons on both sides of the brain, but most males have them only on the right side." As a result, girls often become earlier readers than boys and begin the writing process sooner. Many girls have less spatial awareness than boys but, at the same time, develop fine motor skills earlier than many boys. Most boys, however, tend to be more attracted to spatial tasks (such as playing with Legos) than most girls.
Most girls can (and will!) talk about emotion more easily than boys.
Most girls' and boys' brains are wired to process the connection between language and emotion differently. Because of this, according to Deak, many girls may have an easier time talking about their feelings than many boys. In addition, female brains tend to focus a bit better on details, so that girls can express their emotions at considerable length. Girls (particularly pre-pubescent ones) also have greater sensitivity to noise and tone of voice. As a result, some girls may hear yelling when there is only firmness in an adult's voice, or take feedback on their work as negative criticism, even when it's constructive.
Girls and boys react differently to stress.
Hormones shape how girls' and boys' brains react to fear and stress. Under stress, every body releases hormones such as epinephrine or cortisol, which prepare the body for fight or flight. However, recent research shows that females also produce oxytocin, a hormone connected to childbirth that is thought to enhance connection and caring. From a species survival standpoint, this response may increase the probability that females will take care of offspring or band together when threatened. Deak terms this the "double whammy" that makes risk-taking harder. "This increases the likelihood that a threatened female will get out of the situation rather than fight. Boys, on other hand, get a surge of testosterone, which can modulate fear and promote aggression." Deak encourages parents to help their girls take important risks and assert themselves in challenging situations.
Anatomy is not destiny.
The research does not claim that all girls' (or boys') brains work the same way, or that a girl's behavior is predestined by brain chemistry. Catherine Steiner-Adair notes also that the research does not fit all girls. "If 20 percent of girls do not fit this pattern, that's one out of five, and that's a pretty big percentage. We therefore shouldn't make any assumptions about all girls' behavior being the same."