Now, this is really important because the child is learning that they, they can
have representations of objects. And that's very important for cognitive
development. In the Preoperational stage, from two to
seven, the child is developing language. So, it really is developing a conceptual
way in which to think about its world. And it fully can represent objects and
events when they're not present. In the concrete operational stage, from
seven to 11, now the child is beginning to have complex manipulations of
representations of concrete objects because it has language and is able to do
that. And it can classify objects into
categories and hierarchies. For example, it might see a dog and have
a concept of dog, a representatioin of what a dog is.
But it might ear-, in very early part of it's development of categories, say, that
all four legged creatures are dogs. But then it sees a cat.
And mom says, No, that's not a doggy, that's a cat.
It starts developing new categories and new hierarchies, ways of representing
objects. And then it, for the first time shows
conservation. Conservation of quantity, mass, volume.
In other words, let me just show you the example what a conservation test might
look like. We might have two cylinders filled with
water, and I'll take one of the cylinders, and I'll pour into a another
cylinder. So, it looks like that.
And then I ask the child, which cylinder has more water in it.
Even though it saw that I poured from one cylinder to the other, it will always
pick the tall one. It doesn't have conservation of mass or
conservation of volume. It simply looks at which one is taller.
And this is important because it shows that the child can make inferences about
the manipulation that I made. And it could be with number.
It could be with size. It could be with anything that I can
manipulate. But the child still will think, if I take
five coins and spread them out over a larger area, then it would say that has
more coins in it, than the five coins over a smaller area, or the conservation
of volume that you see here. Piaget's Theory has some processes that
are very important. First, this idea of cognitive development
being a representational acquisition. In other words, the child acquires
schemas, these, these categories in which to place things.
A cognitive structure or pattern by which we organize the world through schema or
schemata. Now, he does that in two ways.
First as assimilation, we incorporate our experiences of the world into existing
schemas. So, if I learned that all four legged
animals, cats, dogs, zebra, are mammals, then I might develop that hierarchic
through assimilation, taking new objects and bringing them in to existing schemas.
Or, I can create new schemas or chain schemas when necessary.
So, when I find that a zebra is not really a horse but a seperate category,
now I develop a new, through accommodation, I develop a new category
of zebras which is different from horses. So, it's a constant changing of the
schemas that we have and adding new schemas or changing schemas or adding new
objects into existing schemas that allows cognitive development to occur.
It allows us to organize the world in meaningful ways through our use of
language. So, cognitive development, according to
Piaget, is a continual process of assimilating, as long as possible, and
accommodating by making new schemas. And that's how we develop cognition.
Let me just, one other task that's very important, and so the idea that before we
are able to take other people's perspectives, our perspective is the, is
the thing. And he developed this mountain task,
where he stood with a child in front of sort of a, plastic mountain.
And then, showed the child pictures of, of the mountain from different
perspectives. He said, which one is my perspective?
The child when, when it's egocentric, would always pick his own perspective.
Looking at the mountain from his height, not from the height of the experimenter.
So, Piaget's theory has had certain kinds of challenges since it was developed.
First, are the stages as discrete and as consistent as Piaget argued?
No, the correspondence between the different tasks is really relatively low.
It's important to know that these are the different ways in which the child can
interpret their environment but the actual correlation with stages is not as
strong as Piaget would believe. Is, if the egocentric test is made
simpler, then the child, like flat-, flatter mountain for example, then the
child can actually, at a younger age, develop other peoples perspectives as
well as their own. And, also the conservation is present at
younger ages if you test it just the way, just right.
But it does not generalize with other conservation task until about seven as
Piaget suggested. So, there have been some challenges to
the theory, but it has also been a very important contribution to understanding
development, especially development cognition.
Thanks.
