Brain Rules for Baby (Updated and Expanded). John Medina
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the reasons, the baby seems to be going to great lengths to get you to leave it alone.
How good are we at leaving baby alone—at this stage or any other in the womb? Not very. Most parents have a gnawing desire to do something to help baby, especially when it comes to baby’s brain. Fueling that drive is an enormous sector of the toy economy whose sole strategy is, I am convinced, to play off the fears of well-meaning parents. Pay close attention, for I am about to save you a ton of money.
Pregaphones and prodigies
Shopping in a toy store several years ago, I came across an ad for a DVD designed for newborns and toddlers, called Baby Prodigy. The flier stated: “Did you know that you can actually help to enhance the development of your baby’s brain? The first 30 months of life is the period when a child’s brain undergoes its most critical stages of evolution… . Together we can help to make your child the next Baby Prodigy!” It made me so angry, I crushed the flier and threw it in the garbage can.
These outlandish claims have a long history. The late 1970s saw the creation of Prenatal University, a for-purchase curriculum that claimed to boost a baby’s attention span, cognitive performance, and vocabulary, all before labor. The kid actually received a degree declaring him or her “Baby Superior” after birth. The late ’80s introduced the Pregaphone, a glorified funnel-and-speaker system designed to pump into a pregnant woman’s belly the mother’s voice or classical music or whatever other IQ-boosting noise du jour. More products soon followed, complete with some extraordinary advertising hype: “Teach your baby to spell in the womb!” “Teach your child a second language before birth!” “Improve your baby’s math scores by playing classical music!” Mozart was a particular favorite, culminating in something you may have heard before: the Mozart Effect. Things did not get better in the 1990s. Books published in that decade outlined short, daily activities for pregnant couples claiming to “raise your baby’s IQ as much as 27 to 30 points” and increase your baby’s attention span “as much as 10 to 45 minutes.”
No commercial product has ever been shown to do anything to improve the brain performance of a developing fetus.
If you walk into any toy store today, you are bound to find products making similar claims. Almost none of their assertions are backed up by in-house testing, let alone backed up by independent, peer-reviewed research.
Crinkle. Toss.
Believe it or not, no commercial product has ever been shown in a scientifically responsible manner (or even in an irresponsible non-scientific manner) to do anything to improve the brain performance of a developing fetus. There have been no double-blind, randomized experiments whose independent variable was the presence or absence of the gadget. No rigorous studies showing that an in utero education curriculum produced long-term academic benefits when the child entered high school. No twins-separated-at-birth studies attempting to tease out nature and nurture components of a given product’s effects. That includes the in utero university. And the in utero Mozart.
Sadly, myths rush in when facts are few, and they have a way of snaring people. Even after all these years, many of these products are still out there, functioning like untethered gill nets, trapping unsuspecting parents into parting with their hard-earned dollars.
The rush to create marketable products is appalling to us in the research community. Their spuriousness is also counter-productive. These products generate so much attention, they can obscure the reporting of some truly meaningful findings. There are activities that expecting parents can do to aid the cognitive development of their baby-under-construction. They’ve been tested and evaluated, with the results hashed out in refereed scientific literature. To understand their value, you need to know a few facts about the developing infant brain. Once you get a peek at what’s really going on in there, it will be easy to see why so many products are just hype.
Let’s get it on
The opening cast members of the baby-making play are simply a sperm and an egg and a saucy Marvin Gaye song. Once these two cells are joined, they begin producing lots of cells in a small space. The human embryo soon looks like a tiny mulberry. (Indeed, one early development stage is called the morula, Latin for mulberry.) Your mulberry’s first decision is practical: It has to decide what part becomes baby’s body and what part becomes baby’s shelter. This happens quickly. Certain cells are assigned to housing construction, creating the placenta and the water balloon in which the embryo will float, the amniotic sac. Certain cells are assigned the duties of constructing the embryo, creating a knot of internal tissues termed the inner cell mass.
We need to stop right here and contemplate something: The inner cell mass at this stage possesses a cell whose entire offspring will form the human brain. The most complex information-processing device ever constructed is on its way. And it starts out a fraction of the size of the period at the end of this sentence.
I have been studying this stuff for more than 20 years, and I still find it amazing. As scientist Lewis Thomas put it in The Medusa and the Snail: “The mere existence of such a cell should be one of the great astonishments of the earth. People ought to be walking around all day, all through their waking hours, calling to each other in endless wonderment, talking of nothing except that cell.” Go ahead, call your neighbor; I’ll wait.
The miracle continues. If you could see it in action, this embryo floating in seawater, you would notice that the inner cell mass is actually swarming with cells, scurrying around like busy short-order cooks at the county fair. The cells arrange themselves into three living layers, looking for all the world like a cheeseburger. The bottom bun, called the endoderm, will form most of the cell systems that line your baby’s organs and vessels. The burger layer, the mesoderm, forms your baby’s bones, muscles, blood, and various connective tissues, amongst other systems. The top bun is the ectoderm. It will create your baby’s skin, hair, nails, and nervous systems. It is within the ectoderm that the miraculous little pre-brain cell resides.
Looking closer, you would see the tiniest line of cells forming atop the bun’s center. Below, a log-shaped cylinder begins to form and elongate itself, using the overhead line as a guide. This cylinder is the neural tube. It will give rise to the spinal column—the far end of the log becoming your baby’s butt, the near end becoming baby’s brain.
When something goes wrong
It’s vital that this neural tube develop properly. If it doesn’t, the baby could have a protruding spinal cord or a tumor near his lower back, a condition known as spina bifida. Or the baby could grow without a complete head, a rare condition known as anencephaly. This is why every pregnancy book strongly recommends taking the B-complex vitamin folic acid: It helps shape the proper neural tube—both the near and far ends. Women who take folic acid around conception and during the first few weeks of pregnancy are 76 percent less likely to create a fetus with neural tube defects than those who don’t take the supplement. It is the first thing you can do to aid brain development.
Parents-to-be throughout history have worried about whether their babies are developing properly. In 1573, French surgeon Ambroise Paré catalogued the events to which prudent young pregnant couples should be alerted to avoid a child with birth defects. “There are several things that cause monsters,” he wrote in On Monsters and Marvels. “The first is the glory of God. The second, His wrath. The third, too great a quantity of seed [sperm]. The fourth, too little a quantity.” Paré hypothesized that a birth defect could be caused by indecent posturing of mom (she sat too long with her legs crossed). Or it could be due to the narrowness of the uterus, demons and devils, or the wicked spittle of beggars.
We can perhaps forgive Paré’s pre-scientific misunderstanding of in utero brain development. Even to the modern mind, it is scary, hopelessly complex, and mostly mysterious. Researchers today are at a complete loss to explain nearly two-thirds of all birth defects. Indeed, only a quarter of all known birth defects have been tied to an isolable DNA problem. One of the reasons we know so little is that mom’s body appears to have a fail-safe mechanism. If something goes wrong during development, her body often senses trouble and deliberately induces a miscarriage. About 20 percent of pregnancies end in spontaneous abortion. Known environmental