Your Baby’s Brain Development
Before and After Birth
Your baby’s brain began to develop about 18 days after conception. Like all organs in the unborn child, the brain develops rapidly throughout pregnancy. But the brain differs from the other organs in one important way. The rest of the organs (the heart, the liver, the lungs, etc.) are fully developed and fully operational by the time a baby is born and continue to change only in size over the course of development. But the brain continues to develop and mature long after birth. Some parts of the brain aren’t fully developed until late adolescence and early adulthood (Would it surprise you to learn that those are the areas that control good decision making and impulse control?) In fact, many developmental psychologists refer to the first three months of a baby’s life after birth as the “fourth trimester” because so many of the brain’s regions are still developing at this point.
Prenatal Brain Development
Once specialized brain cells, called neurons, begin to develop 18 days into pregnancy, the brain goes into overdrive, producing neurons at an unbelievable rate. Some estimates place the rate of neuron development as high as 250,000 brain cells per minute during peak times! One of the most interesting and unintuitive facts about brain development is that before birth, your baby’s brain manufactures many more neurons than she or he will ultimately need. As many as 70% of them will ultimately be “pruned” and will die off. Why do babies’ brains produce so many more cells than they need? To ensure that all brain regions that need them have as many cells, and connections among cells, as they need to coordinate behavior. Throughout the second and third trimesters, cells begin to migrate in the brain, moving to their final positions in a particular structure of the brain, such as the visual system, the region that controls movement, or the system that controls emotions.
Starting late in pregnancy but continuing well after birth, the process of pruning begins. At this stage in brain development, the brain begins to streamline its functioning, improving effectiveness of organization and communication among brain structures by building and strengthening the useful connections among individual neurons that share related functions and trimming away those neurons that aren’t helping the different parts of the brain to communicate with each other. Think of vines growing over a trellis. Those vines that are reaching towards each other to cover the trellis completely are ones we want to keep, but the vines that are growing out into space or down towards the ground need to be pruned.
Continued Brain Development During Infancy
Growth of neurons in some brain areas and pruning in others continues well after birth. Early experiences serve as the pruning shears that help improve babies’ brain functioning. There are a variety of aspects of babies’ brains that aren’t finished developing at birth. For example, infants’ brains aren’t able to process depth perception until 3 to 4 months of age. The hippocampus, the area of our brains responsible for building memories, continues to mature throughout the first year of life and beyond, which may explain why we rarely remember things that happened to us earlier than the age of 3 or so. And some of the most important areas of the brain, those responsible for decision making, planning, and impulse control don’t fully mature until late adolescence which explains why kids can run out into the street without thinking about the fact that there might be cars passing and teenagers decide to skateboard off a 6 foot incline –they aren’t fully thinking through the consequences of their actions.
What Can Parents Do To Facilitate Their Baby’s Brain Development?
What’s the take home lesson regarding brain development for you as a new parent? One of the most important things to keep in mind about brain development is that the brain continues to change, develop and build connections throughout childhood and it needs stimulation to do that. The more focused interaction and stimulation (in the form of conversation, reading, play, toys, and games) the more the brain has to chew on. This ensures that your baby’s brain is fine-tuning itself in ways that optimize its ability to perform these same sorts of functions throughout childhood and into adulthood.
Does that mean that we need to stimulate our babies all the time? Not at all. Babies need plenty of rest, of course, and are not going to be receptive to interactive stimulation when they are fussy, hungry, or tired. But your baby will have moments (they’ll be rare and fleeting early on but will become more frequent as your baby matures) when she or he is calm, alert, and attentive. Those are the windows of opportunity to provide your baby with some interactive stimulation. That can be as simple as talking or singing to your baby, or waving your fingers or a toy in front of him or her to get your baby to practice orienting visually to an object in space. As your baby becomes stronger, more alert, and able to reach for, grasp, and mouth objects, be sure that your baby has some infant-appropriate toys within reach. Reading books to your baby is also an excellent way of stimulating brain development. Although your baby won’t understand the stories at 1 or 2 months of age, she or he will enjoy hearing your voice and eventually will enjoy matching the sounds you’re making with the pictures you are showing. This also helps to establish a reading routine for both you and your baby that will ultimately help your baby learn language and build knowledge about the world. As your baby develops more skills and awareness, you can gradually increase the complexity of the stimulation you provide. The give and take, the action and reaction of play and reading with your baby is something that can’t be replicated by showing babies videos, no matter how educational the content might sound, simply because a video can’t provide real interaction and reaction to your baby’s specific behaviors at a specific point in time.
Some new parents feel silly interacting with their babies before their babies are able to respond, but it’s important to realize that there are countless changes going on inside your baby’s head as a result of the stimulation you’re providing. Even though it might not be obvious from their behaviors, the stimulation you provide is every bit as important to your baby’s brain development as feeding and bathing are to the rest of the body. Nourishing your baby’s brain will contribute to a happy, healthy baby.
