Psychology 101: Intro to Psychology

How is prenatal development related to psychology? How are minds forming in the womb still linked to the outside environment? This lesson explores the stages of prenatal development and a mother's ability to affect her unborn child.

You're probably wondering how what happens to a baby before it's born is related to psychology. We typically think of babies' development inside their mothers as more physical than psychological. But since the brain is growing and changing during this time, healthy prenatal development is actually really important for giving babies healthy, properly-functioning minds. Think of it like a computer; long before a computer ever tries to run software, its hardware needs to be put together properly. If any of its wires are crossed or missing, the software won't run as well. If the development of the baby's body and brain are disrupted, it can affect the way a baby's mind, or software, runs on it later.

First, let's cover some of the basics. Each one of us starts out as a zygote, which is an egg cell that has been fertilized by sperm. Once fertilized, the egg cell begins to divide itself in two, then into four, then into eight--multiplying itself into a little cluster of cells. While all this is happening, the zygote heads down to the uterus and tries to attach itself to one of the walls. If it does (and only about half of them are successful!) it's called an embryo. This embryo continues to divide itself and grow larger, but something else really important and cool starts to happen as well: the cells begin a process known as differentiation, where they start to turn into all the different kinds of cells in our bodies--blood cells, skin cells, etc. The cells before differentiation are kind of like high school students. They all take basically the same subjects and earn the same high school diploma. But when they get to college, they start majoring in different subjects; one might turn into a biology major, and another into an English major. Students in college are more like the cells in an embryo after differentiation; they start to specialize in different subjects, or functions in the body.

After about nine weeks, the embryo is referred to as a fetus. All of foundations for the babies' major systems and functions have been laid, and the rest of the pregnancy is devoted to helping the fetus grow and fully develop. If all goes well, a healthy baby is born after about nine months!

Unfortunately, there are things that can interfere with normal prenatal development. You've probably heard that women who are pregnant shouldn't drink alcohol. This is because alcohol is a teratogen, or a substance that interferes with normal prenatal development. Other teratogens are things like radiation, certain chemicals and some prescription drugs. To return to our computer analogy, a teratogen is kind of like if when you were building the computer you accidentally spilled some soda on a few of the wires. You can't clean it up, so you just continue building, but you never really know until you try to run some software whether the spill will affect the computer's functioning or not. Sometimes it does; sometimes it doesn't. Some babies whose mothers drink alcohol during pregnancy turn out fine; but others are born with fetal alcohol syndrome, a set of abnormalities that include physical differences as well as mental retardation. Exposure to teratogens at certain sensitive periods during development are more likely to result in abnormalities; also, more exposure over a longer period of time is also linked to higher chances of birth defects.

Even though prenatal development is primarily important for laying the groundwork for a healthy mind, there are a few psychological developments that happen in the last few months of pregnancy. Babies start to become familiar with their mother's voice while still in the womb; once they're born, they prefer it above other voices, which helps with mother-infant bonding. They also may start to recognize what kinds of sounds are present in the language they'll eventually speak. There is some evidence that fetuses can respond to their mothers' moods. Some researchers found that they moved around more when their mothers were watching happy movies. Though some parents are convinced that playing classical music near a developing fetus can improve its intelligence, there's really no evidence that this works.

So we've talked about how prenatal development is related to psychology. Mainly, it's important in the sense that well-built hardware is essential to running software; things that go wrong in the building process, like exposure to teratogens like alcohol, can have physical and cognitive consequences. There are also some important early psychological developments that occur in the womb, like recognizing the mother's voice and hearing language sounds.