Baby's Brain in Week 17
By now, your baby notices whether a picture is placed horizontally or vertically, he can tell the difference between pictures with two things in them and three things in them, and he can detect patterns. Combine these skills with his impressive tracking abilities, and it's clear you're raising quite a looker!
What the Research Shows
We know these facts to be true through research studies that involve a procedure called habituation and dishabituation. When babies habituate to a certain event, they become bored of it. When they dishabituate, they reengage; they realize that something has changed by showing renewed interest.
To illustrate this, researchers showed babies a series of pictures placed horizontally. For a while the babies showed interest in the pictures, but then they habituated, turning away to look at something else. Then when presented with the same picture in a vertical position, the babies dishabituated by showing interest anew. They were aware of the difference in the presentation of the pictures.
Ditto for pictures featuring differing amount of items: Researchers showed babies pictures with two objects—say, two dogs, balls, or cups. At first the babies were highly interested, but then turned bored, habituating. But the babies perked up and stared when shown these same pictures again, now with three cups, dogs, or balls in them. Dishabituation!
In an even more surprising trial, the researchers first habituated each baby to a set of matching shapes (circles and diamonds). Each set included a small shape placed over a large one. Then they showed each baby two new sets of shapes, this time using triangles and the same pattern, small over large. The babies' response? "Ho hum, same old boring small thing over big thing." But when the researchers changed the pattern to big triangle over small triangle, they could see each baby thinking, "Hey, here's something new!" The babies had alerted to the pattern's change.