Now we know from decades of research that too little stimulation early on is bad for brain development. I show you here two PET scans. Now PET scans are measures of brain function; the brighter colors show more brain activity. And on the left is a PET scan of a normal kindergartener and on the right is a PET scan of a child who was raised in a horribly neglected environment. This is actually a PET scan from a child who was raised in a Romanian orphanage and was profoundly neglected early in life. And you’ll notice that the areas of his brain that show no activity at all, it didn’t develop as a result of too little stimulation.
Now this is a horrific example of too little stimulation and the untoward consequences of it. But the question we’ve had in our lab for some time is: What about too much? Is it actually possible to over-stimulate the developing brain or more appropriately to inappropriately stimulate the developing brain in ways that are actually not beneficial but harmful? And this is important, because we’re technology-izing childhood today in a way that’s unprecedented.
In 1970, the average age at which children began to watch television regularly was four years, like this cute little girl here. And today based on research that we’ve done, it’s four months. It’s not just how early they watch but how much they watch. A typical child before the age of five is watching about four and a half hours of TV a day; that represents as much as 40% of their waking hours, which brings us to Baby Einstein.
Many of you probably have not seen Baby Einstein but I will show you a random 20-second clip from Baby Einstein day on the farm and here it is.
In that 20-second clip, there were seven scene changes, about one every three seconds. It’s about the most exhausting day on the farm since John Steinbeck’s Grapes of Wrath. And of course, it’s nothing like being on a real farm, right? Adults watching this find it discombobulating, because your mind is trying to make a coherent narrative out of this, and there is no coherent narrative. It jumps all over the place. But babies aren’t trying to make a coherent narrative out of it; they’re not capable of doing that. It’s all of that screen change, all of that stimulation that’s keeping them actually engaged in the screen.
So we’ve had for a while, what we call the overstimulation hypothesis, which is that prolonged exposure to this rapid image change during this critical window of brain development would precondition the mind to expect high levels of input, and that would lead to inattention in later life. So you watched enough Baby Einstein day on the farm as a baby and when you go to a farm as a school-age child it’s boring; it’s too slow: how come there’s no sheep suddenly popping into my face? How come there’s no marionette going back and forth? Why do I have to walk from here to there? That’s the general idea that you’re conditioning the mind to that reality which doesn’t actually exist.
And we tested this some years ago and what we found was that the more television children watched before age 3, the more likely they were to actually have attentional problems at school age. Specifically for each hour that they watched before the age of three, their chances of having attentional problems was increased by about 10%. So a child who watched two hours of TV a day before the age of three would be 20% more likely to have attention problems compared to a child who watched none.
Now what else did we find? We found that the more cognitive stimulation children received, and we measure cognitive stimulation in terms of how often parents read to their child, how often they took them to the museum, how often they sang to them, we found that cognitive stimulation reduced the chances of attentional problems later in life. In fact, each hour of cognitive stimulation reduced them by about 30%. So if you will, these are two sides of the same coin. There are certain things that we can do early on in our children’s lives that enhance their ability to pay attention and certain things that we can do early on that actually impede them.
Now if our hypothesis was right that it’s based on the pacing of the programs, then you might imagine that what children watch actually is important. And so content would be key. And I’ll give you two examples of content to illustrate that point.
The first is The Powerpuff Girls Movie, the right mix of sugar and spice for satisfying rush. I don’t know how many of you have seen that but here’s a scene from that.