By Leah Shaffer

Last year, David Walsh shared with parents the reasons their teens might act like, well, crazy teens. This year, the founder of the National Institute on Media and the Family was back, with an even trickier subject: differences between male and female brains.

 His presentation, which was co-sponsored by the Eden Prairie Schools PTOs, ADC Telecommunications and  The ADC Foundation, was held last Tuesday at Pax Christi Catholic Community.

Well aware that he was treading tricky waters, Walsh cleared up the mistakes that have been made when it comes to thinking about differences in brains.

“We have a history of misusing this information,” he said.

Take for instance, the information that men have larger brains. That used to be used as evidence of a superior male intellect. “Brain size has nothing to do with intelligence,” Walsh said, noting that, if that were the case, whales would rule the world.

In the 1970s people went to the other extreme, saying that there were no differences between men and women. With today’s technology, brain scans show that that is not the case either.

Walsh emphasized that differences between male and female brains do not mean “better or worse.

“It just means different.”

Before getting into the heart of the differences, he also warned that he would be speaking in generalities (keeping in mind there are many individual exceptions).

“Biology does not mean destiny,” he reminded the audience.

Boys, girls, academics

Walsh reviewed the two sides of the brain, the left side being more of an analytical zone, while the right brain is the source of more creative thought. The two sides of the brain are connected by what is called the corpus callosum. That feature of the brain tends to be thicker for women, he said.

 “That facilitates communication between the two hemispheres.”

It turns out that it has been found that the female brain is built with a language advantage.

In general, for baby girls, the left hemisphere of the brain matures first, perhaps facilitating earlier language development, as compared with boys.

In general, for baby boys, the right side matures first, which relates to strength in spatial relations.

Scans also show that, when women engage in language, they use both hemispheres while boys just use the left.

How this could translate to classroom performance is up for some interpretation.

For instance, Walsh mentioned the math gap between boys and girls may be related more toward how math is taught, rather than innate skill. It may be a sociological gap. Girls may learn math better in the form of word problems, based on their strength in language.

He made the point that, experts are not sure yet if reading problems for boys may have more to do with how they handle frustration rather than innate skill. Boys act up when getting frustrated, while girls stay quiet (which leads them to be favored by the teacher). Walsh made the point that things like physical education and recess are necessary for all children to work off energy, so they can focus in the classroom.

“Are we kind of shooting ourselves in the foot?” by cutting PE and recess, he wondered.

Relationships

From the beginning of his lecture, Walsh emphasized the importance of experience in shaping a person’s life, especially as the brain is getting wired.

He reminded people that the “teenage brain is not the finished product.”

Also keep in mind, that teenagehood can go far beyond high school.

In fact, he said, on average, the brain isn’t finished wiring until people reach age 25.

Of course, when puberty hits, so do the main brain differences between boys and girls.

 “There are structural differences in the hypothalamus between boys and girls,” said Walsh.

It works like this:, when boys reach puberty, a part of their hypothalamus, called the INAH-3 gets bigger. This leads to the constant thinking about sex.

“It’s not the same thing going on in the girl’s brain.”

A young woman’s interest in sex comes from hormones, specifically, oxytocin.

This explains why girls go to bathrooms in groups, Walsh joked, calling oxytocin the “cuddling hormone.” It makes for teenage girls that are very focused on physical closeness, relationships.

During his presentation, Walsh compared genetics to hard wiring and experience to the soft wiring of life.

Whether man or woman, he noted,  “experience is important.”