Flashing, noisy child's toys

Why is it that parents are inundated with noisy, flashing toys, by manufacturers who wish to convince us that somehow their products will enhance our children's cognitive development? What is the truth in the matter? Do flashing lights and noises or "music" stimulate a child's cognition?

The first thing to recognize is that a child's brain is quite susceptible to stimulation. As I wrote below, an infant is not a blank slate at birth, but what the child begins with is more propensities than abilities. With the tools that nature has supplied, there are certain capacities that are more likely to emerge than others. Among these are the ability to walk on two legs and to speak a language. There are many others, but we are born with none of them. They emerge from the interaction between our biological endowment, and our interactions with the world.

The infant brain is remarkably adept at identifying patterns, and calculating probabilities from even a brief exposure to data. (See, for example, Saffran, Aslin & Newport, “Statistical Learning by 8-Month-Old Infants,” Science 274, 13 December 1996). What this means is that if we expose our children to redundant sounds (and in the case of most recorded sounds, exact repetitions), rather than stimulating our children's brains, we are inurring them. The balance that must be achieved for optimal development is one between variety and repetition.

Put another way, the child is ever on the lookout for patterns. It is from these patterns that they formulate expectations: mini-hypotheses about how the world works. When our expectations are met, this reinforces our hypotheses; when they fail to be met, we modify the hypothesis, taking into account the variety we have observed. If the stimulus includes exact repetitions, of a sound for instance, like in the case of many electronic toys, the task for the child is easy and readily reinforced. The more the stimulus is repeated, the more established becomes the expectation. The downside of course, is that the child's brain may focus more and more on these easily formed and reinforced patterns, foresaking the more complicated ones. Most importantly, the more we are exposed to exact (or near exact) repetitions, the more difficulty we may have in recognizing similarity! But the recognition of similarity is a paramount skill for human development.

Years ago, I was a skeptic when it came to the surge in diagnoses of ADD and ADHD. I am much less of a skeptic now. I have begun to hypothesize that generations raised on simplistic stimuli as infants have greater difficulty concentrating for extended periods of time, or analyzing complicated streams of information. It is not a matter of them being stupid, simply a matter of the preparation they were given in early life.

Someone who apprentices in carpentry may be quite skilled in ways of the hammer and saw, but dangerously inept when put in a kitchen with a knife, or asked to plant tomatoes. Similarly, a brain raised on daily doses of MTV-like stimuli will be more attuned to these disjunct inputs, but will likely have less skill with more fluid ones. There is a saying in cognitive neuroscience: "neurons that fire together, wire together." This means that the more certain mental calculations are reinforced, the easier they become to process; contrarily the ones that have not been reinforced by experience become atrophied. It is this eventuality that we should ward against.