Is it normal for a baby to be working on something trivial for hours?

What seems to us dull-headed and even boring can be very interesting for your baby. You are not the first mother who discovers that the beautiful rattle with many extra features is fun because there is a label on it! Your baby has an eye for detail. The smallest things can fascinate him enormously.
Sometimes things are so small, so insignificant to us that some parents think the baby is stupid. Some even think there is reason to believe that their child is autistic because he spends hours going with his finger over a doorstep back and forth or turning a ball of yarn in his hands. As a parent you are simply inclined to think the worst, a judgment that is almost never justified. The doing of a dull-headed thing for hours on end is certainly no reason to doubt your child's intelligence. In fact, your baby is probably doing very serious brainwork. He is discovering the basic laws of nature: while going with his finger over the doorstep, he experiences gravity, the material the doorstep is made of, the physical forces that take over when his finger is at a certain point in the curve of the doorstep. The turning of the ball of yarn shows him that the ball gets a completely different appearance by very subtle movements of his hand. We know that something looks different from another angle, but that in fact it is the same thing. Your baby is discovering that, while he turns the ball. So actually, he is doing something very smart!
Your baby's mental development is very important and significant. It affects not only your baby's mood, but also his health, his intelligence, his sleeping pattern, the three C’s (crying, clinginess, crankiness), and much more. Once you understand your baby’s mental development, you can help your baby in so many ways. If you would like to learn more about the mental development of your baby, order a copy of The Wonder Weeks, which is based on international research.
