Giving birth to a better brain
Dp Babies Sharpen Mother's Minds?
By Erica Noonan
© 2005 Boston Globe

Women with small children have long been saddled with an unflattering stereotype as being: incompetent, dull-witted, frazzled, and preoccupied with domestic affairs. The derogatory clichés vary, from ''maternal amnesia" in medical circles, to the colloquial ''placenta brain" in the United States ... and ''porridge brain" in Great Britain.

But a new body of research -- so far still mostly in animals -- is fueling the idea that motherhood may actually rewire the brain, making mothers (and involved fathers) more perceptive, competitive, efficient, and even socially aware.

And sociological studies suggest that most of the symptoms of ''mommy brain" may be due as much to exhaustion and stress as biology.

Comparing the brain of a non-mother to that of a mother is ''like comparing a tree in the winter to one in full bloom in the spring, when it is much fuller and richer," said University of Richmond neuroscientist Craig Kinsley, a leading researcher in the field.

The transforming experiences of pregnancy, labor, and caring for small children ''enables the brain to process information much differently than it did before," he said.

Kinsley and other researchers have found that beginning a few weeks after giving birth, a female rat's cognitive abilities -- particularly smell and visual perception -- start to expand. Rats nursing a litter of pups discover and catch prey three times as quickly as virgin rats, he said.

Kinsley's analysis of brain tissue from rats in late pregnancy showed that neural pathways in the hippocampus, the center of learning and memory, were essentially ''remapped."

The changes, Kinsley and others said, probably come partly from the experience of pregnancy and labor, when elevated levels of estrogen, cortisol, and other hormones literally bathe the brain. The presence of pups and the demands of caring for them also contributes to brain changes in mother rats -- even caretaker rats who have never been pregnant. In repeated studies, mother rats with pups have proven to be bolder and quicker at finding hidden food.

''We believe the pups are having an effect on the mother, enhancing her efficiency," Kinsley said. ''The pups have a paw in their own survival. The mom isn't a passive caregiver. Rather, absorbing sensory information from the pups has an influence on her brain."

The phenomenon hasn't yet been studied in women, but the rodent studies have important implications for humans, said Kelly Lambert, chair of the psychology department at Randolph Macon College in Virginia.

''Rodents have all the same brain parts we have," she said. ''Human brains are thicker and more complex, but as a model it's a very reasonable place to start."

Pulitzer Prize-winning journalist Katherine Ellison made worldwide headlines earlier this year with her new book, ''The Mommy Brain: How Motherhood Makes Us Smarter," which looks at the experience of mothers in the context of new advances in brain research.

Ellison delayed motherhood until age 37 for fear it would doom her intellectual life. But two babies later, she actually felt more efficient and ''smarter" than ever.

''Although I'd had newspaper deadlines before, never had I been responsible for deadlines involving other people's lives and I found that duty made me more alert and focused," she wrote. ''I had many more reasons to worry, yet to my surprise, I felt calmer. And I kept running into other mothers who felt the same way."

But the news hasn't reached many pregnant and post-partum women, who often too-willingly buy into the ''Jello-brain" stereotype.

In effect, this creates a self-fulfilling prophecy, said Ohio University neuropsychologist Julie Suhr.

Women in their third trimester, who were told they were being tested to see how the pregnancy had affected their memory and performance, scored significantly lower than equally pregnant women who were given the tasks without explanation. The pregnant women were clearly affected by the negative stereotypes about their brains, Suhr's students found.

"In essence, it shows that we can talk ourselves in and out of things," Suhr said. ''They performed badly if they thought they would."

Lack of sleep, the absence of adult companionship, and a shortage of time for exercise and relaxation can also make all parents -- men and women -- feel duller than they really are, Suhr said.

New fathers escape the brunt of maternal prejudices. But research in mice suggests they may still enjoy some of the same brain boosts of parenthood, as well as some of the biochemical changes exhibited by females.

Kinsley and Lambert found that father mice and marmosets performed better than non-parents at tests of foraging and remembering the location of hidden Froot Loops. And like mother rats, father rats experience growth in brain cells after fathering pups, albeit much smaller growth.

In the past five years, research into ''Daddy brains" has revealed expectant fathers experience the similar, smaller spikes in prolactin and estrogen levels well-documented in pregnant women.

Maternal brain research in animals has so far focused largely on cognitive tasks directly related to mothering, like foraging for food and seeking out shelter.

But some researchers say it isn't unreasonable to think that increased learning, performance, and efficiency could extend to other aspects of human life, including the workplace.

In a study of women and leadership, Sumru Erkut, associate director of the Wellesley Centers for Women at Wellesley College, found that in a survey of 60 high-achieving women, many said they used their more limited time at the office to get more done, and employ their newfound ''Emotional IQ" and management skills to increase office output, she said. They cited their use of traditional mothering techniques -- such as empathy and understanding -- to manage employees.

None of the women in the Wellesley study cited motherhood as a detriment to their work, Erkut said, although many women in the contemporary workplace regularly downplay their roles at home.

''Historically men have credited military and sports backgrounds as giving them tools to be leaders," said Erkut. ''It's not out of the question that women would someday list motherhood on a resume with pride, instead of trying to cover up the fact she's stayed home for a time."
Boston Globe

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