The basic procedure used by many of our behavioral studies is called habituation. Habituation procedures take advantage of infants’ natural tendency to look longer at things they have never seen before. In the first habituation phase, we show the infant a series of images that are all matched on some dimension.
The infants tend to look at the first few images for a long time, but the amount of time they spend looking declines as they see more of the same thing. Once the infant has become accustomed to these images, we show them the test images that are different on the dimension we wish to study.
If the infants show an increase in looking time to these stimuli, it suggests that they recognize them as different from what they had seen before. In the example depicted below, a recovery in looking time would suggest that infants are able to discriminate one circle from four circles.