Piaget's stages of cognitive development

- [Instructor] A long time ago, people used to think that children were just miniature versions of adults, and that they thought in pretty much the same way. But then this guy Piaget came along and he figured out that children actually reason quite differently. In fact, he believed that children are actively constructing their understanding of the world as they grow, so that as their bodies grow, their minds grow as well. He thought that this happened generally in different stages. So, I want to tell you about Piaget's four stages of cognitive development. First, we start out with zero to two years. At this point, children are said to be in the sensorimotor stage. This word kind of makes sense. Sensori just comes from the senses. So he said children gather information about their world with their eyes, so through sight, smell, taste, hearing, and touch. So that's why whenever you see a baby zero to two years, they're always touching stuff and putting it in their mouth. Then the motor part is that they are very active. As they discover how to use their senses, they also discover how to move their bodies around. This helps them explore the world and learn what they're capable of. The main task or awareness that develops during this time is object permanence. This just means that infants don't recognize that objects still exist even though they can't see them. For example, if you give an infant a toy or something, say you have a nice ball for them, and you take it away, they won't look for it because they don't understand that it still exists. The next stage occurs from about age two to right around six or seven years. The reason I'm being a little wishy-washy on the years is because these are really just general guidelines. It's not really hard and fast rules of when these stages happen. The next stage is the preoperational stage. The operational part just means mental operation, so imagining things or mentally reversing actions, things like that. The thing to notice about this phase is that this is really when children start to develop and engage in pretend play, and they'll begin to be able to use symbols to represent things. What you might notice is that around age two is also when children learn to talk. As they learn that words symbolize objects, that starts to help them into the preoperational stage, and understand the idea of symbols. Children of this age are very egocentric. That's not a bad thing. They're not just arrogant and bragging all the time. They just don't understand that other people have a different point of view than they do. If you're ever watching TV with a child, like a five-year-old, they might sit down right in front of you and not understand that you can't see through them, because they can see. Also, sometimes kids will try to hide from you at this stage by covering their eyes. The whole, I can't see you, you can't see me idea. Then once they get to about age seven to about age 11 years old, then they are in the concrete operational stage. Again, remember operational means mental operations, and now they can do concrete operations. So this is where children learn the idea of conservation. If you know a little kid and want to see what stage of development they're in, then you can do this little test. It's pretty fun. It's easy. You take two identical glasses and pour the same amount of water in them, and show them to the child and say, "Which one has more?" And kids will tell you they all have the same amount. Then, right in front of the child, so that she sees you, you take one of those glasses and pour it into a short, fat glass. Then you take the other one and pour it into a tall, skinny glass. Then right away, ask the child again, "Which one has more?" Up until concrete operational, the child's going to say the tall, skinny glass has more because the water's higher. But once they reach the concrete operational stage, and understand that the amount of water doesn't change just because the glasses are different sizes, then they'll tell you that they both still have the same amount of water, even though they look different. So that's a fun little test. At this stage, children can also begin to reason about mathematics. They'll be able to understand that 8 + 4 = 12, and then that must mean that 12 - 4 = 8. Moving on up, children from about age 12 and up are in what Piaget called the formal operational stage. That's when children are able to reason about abstract concepts and think about consequences of potential actions. They're able to reason out what might occur. Also, Piaget thought that this is where really sophisticated moral reasoning began to take place. At this point, children are reasoning more like adults, and they continue to develop that over time. Later developmentalists have come along and figured out that these stages aren't quite so discreet as Piaget may have originally thought. Children don't always develop these abilities within the certain age brackets, but they do tend to progress in a predictable fashion. Thanks to Piaget, now we know that children are more than just miniature adults. So, go find a child and see what stage they're in. Test Piaget's theory yourself.