Cognition Lab Director Studies How Much Babies Know
Parents are fascinated by what their infants do, but David Rakison is interested in what they think.
Rakison, an assistant professor of psychology, is the director of Carnegie Mellon's Infant Cognition Lab, which studies how babies process information and learn about the world around them.
"Studying babies is like studying the Big Bang of cognition. It is where you can see the building blocks of cognition coming into being and taking shape, and you start to see the structures that come to make up our adult cognitive universe," Rakison said.
Rakison's research focuses on infants' abilities to categorize objects. The way we categorize objects is fundamental to how we learn about the way objects are related, and how we code experiences in memory.
"Without categories, the world would be an overwhelming place. Categories allow us to chunk information so that when we encounter new objects, we can infer all sorts of things about them," Rakison said.
For example, once we have formed a category for "dog," we can make quick decisions about whether other animals can be categorized in the same way based on their characteristics. And with infants, Rakison can study this process without having to filter out the influences of experience and education that impact how adults make sense of the world.
Rakison's work may not be child's play, though you wouldn't know that by walking into his office. His windowsill is adorned with numerous toy cars and animals, which, Rakison explains, are not for his amusement. Researchers use them to model an action for an infant, and then monitor which toy the baby uses to imitate that action. For instance, if Rakison moves a toy seal along the table, like an animal moving, a baby will pick out another toy animal to imitate this action, rather than a toy car. Although the toy animals are not identical, an infant understands that they are related, but are different from cars.
"Babies are better at learning to categorize than adults in lots of ways. They can pick up on details around them that adults would not. In those senses babies are really smartbut in other senses they are not," Rakison said. "For example, infants can tell that dogs are different from cats when they are three months of age, but they do not know that dogs and cats are alive until they are three years of age."
Results from studies like Rakison's provide valuable information about the way infants think and learn. Through his research, he has learned that 16-month-olds can recognize cause-and-effect relationships and that infants as young as 14 months learn that dogs walk because they have legs, and vehicles move because they have wheels.
This kind of information has practical applications. If we know how infants generally tend to develop, it is easier to study how some children develop cognitive skills differently, such as autistic children. The categorization studies described above are also being done on autistic infants in conjunction with Pittsburgh's Children's Hospital.
"Because we know how normal children respond in these studies, we can gain insight into autistic children's cognitive abilities by examining their performance in the same tasks," Rakison explained.
Like most developmentalists, Rakison has to use innovative techniques to discover what infants are thinking and feeling. One of these methods is to measure how long an infant looks at one object compared to another, or at a series of events. This can show how interested they are in an object or even if they can differentiate objects and form categories.
During a typical experiment, infants watch repeated events on a computer monitor. As they see the event over and over, they become less interested, and the amount of time they look at the event decreases. When their looking time has decreased substantially, they are shown new events that have distinct differences from the previous event. If infants look longer again at this new event, it shows that they noticed a difference between the old event and the new one.
The aforementioned toys are another example. Rakison employs a method called sequential touching, in which four toy cars and four toy animals are placed in front of an infant. The baby will touch the toys in sequence, by category; in other words, they will touch all the animals before touching the cars, or vice versa.
The idea of letting researchers perform experiments on babies sounds scary to some parents, but in reality, the procedures are simple and can be fun. During a visit to the lab, an experimenter explains the study to parents, assuring them that all of their child's data is confidential. Parents even receive a small gift for their cooperation and tend to be happy with their visits. Many of them return to participate in more experiments. "We found it very easy to do," said one mother. "[My daughter] seemed to enjoy it."
Although Rakison is a new face in the field of psychology, his work is becoming more and more well known. Oxford University Press recently published Rakison's first book, "Early Category and Concept Development."
Working with infants and studying their development eventually can lead to knowledge about why we function the way we do as adults.
"Infants are the best window into our adult knowledge of the world," Rakison said.