Video: Skills and the brain grow together
HGSE Professor Kurt Fischer
Video 1: In this video clip, Kurt Fischer, from HGSE's Mind, Brain, and Education program, talks about exciting research findings that relate growth in skills to growth in brain activity. He provides an overview of this work, describing growth spurts in brain and cognitive development that occur within the same age periods during the school years.
"Hi, I'm Kurt Fischer. I study cognitive development and learning, and how they connect to brain development. In research over the years, we came up with a remarkable surprise, which is a discovery of a close connection between the growth cycles of cognition, how we develop new capacities, and the growth cycles of brain activity. I'm going to tell you about that today.
So in cognitive development, there's a series of capacities that emerge during the childhood and adolescent years. And these changes, these emerging capacities can be seen very simply when you look at the best performance that children show. You look at how they solve problems or how they learn in situations where they're given support by a good teacher, by a parent, by a good textbook, helping them to do their best in the task or problem.
And when you look at that best performance, you see rapid jumps in performance at certain ages, as you can see in this graph. At about four years, seven years, 11, 15 and 20, you see jumps in performance under optimal conditions, the best that a child can do. When you look at ordinary performance on the other hand, you see slow, continuous growth at a much lower level as you can see in the bottom curve in the graph.
Now it turns out that brain activity, the electrical activity that can be recorded from the cortex, shows a similar growth curve. What we're going to show you is the energy in the brain wave and how it changes over time with age. In this graph, you can see that there's a series of jumps in the energy in the brain wave that looks a lot like the series of jumps that you saw before in cognitive performance under optimal conditions.
And if we then take that graph and change it into different scores where we subtract last year's performance from this year's performance, so we see the change from year to year, then you can see that even more dramatically that there's a series of spurts that are closely tied to age. And these ages relate very nicely to the ages when cognitive performance occurs.
So a surprising discovery is that cognitive growth and brain activity growth occur in parallel with the capacities to think and solve problems, developing in spurts at particular ages. And the brain activity growth occurring at spurts at the same ages. So brain growth and cognitive growth are going hand-in-hand in the development of new capacities during childhood and adolescence."
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Video 2: Kurt Fischer elaborates on measuring the growth in brain activity from childhood through early adulthood. He describes how EEG (electroencephalogram) techniques can be used to detect developmental patterns in brain connections. Animated graphics help to illustrate how connections among different brain regions appear to grow in cyclical patterns around the cortex.
"When we talk about brain growth, what is growing? And how do we know the way it grows? The way we figure that out is by looking at what's happening in brain activity. And the best measure right now is the electroencephalogram, the EEG, which measures the electric activity in the cortex primarily.
The levels that we talked about where there are spurts in electrical activity, measure the energy in the activity. There's another way that we can use brainwaves which lets us examine how connections grow in the brain. It turns out there's a really nicely systematic and surprising pattern of growth of connections moving around the cortex and association with each of the developmental levels.
So for each level of growth, we start out with front to back connections, then move to connections growing primarily in the right hemisphere where they gradually become more local within the right hemisphere. Then they move to primarily the front of the brain briefly, then over to the left hemisphere where they move from being local to more global. And then the whole thing starts over again.
We have front to back growth of connections, moving over into the right hemisphere where they gradually become more local, then to the front of the brain briefly, then moving over into the left hemisphere, and then starting over again.
So over the time of development from early infancy to the mid-20s, as you move through the ten developmental levels of growth, we presumably have this growth of connections in the neural network repeating each time for each level."
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Video 3: Learners of all ages build more complex understandings of the world and of people from their earlier, simpler concepts. In this clip, Kurt Fischer uses the example of children's social role understanding to illustrate how simple representations are reorganized into more complex representations and then into abstract concepts. These new skills that emerge in children's best performance are closely associated with growth spurts of brain activity.
"Let's say a little more – unpack – how cognitive development occurs. Cognitive development proceeds through ten levels from early infancy into the middle 20s. And the levels move through a growth cycle, beginning with actions, becoming more and more complex during the infant years, building to representations, which then become more and more complex during the childhood years. And finally abstractions emerge around the beginning of adolescence and they become more and more complex on into early adulthood.
So we have a growth cycle moving from actions to representations to abstractions. The diagram shows this cycle for representations and abstractions. Starting about two years, children can build single representations like a building block, such as the concept of mother. They understand what a mother does. That gets combined with other social categories like what a child does. So right about four years, they can connect mother role to child role, understanding how mother and child interact.
Then a couple years later, at about six or seven, they build a system where each person can occupy several roles. So a mother can also be a teacher with her child who's also a student or learner. This complex representational system then builds further to create the emergence of a new way of thinking, a radically new way of thinking which is an abstraction, a kind of intangible concept, something like executive or introverted person or principal understood as the leader of a school, as opposed to merely the boss of students and teachers.
Then the abstraction goes through the same cycle as you can see in the diagram. So single abstractions move into abstract mappings, connecting abstractions to each other in simple ways, then abstract systems that build complex relations among several abstractions. And then eventually the abstractions can become coordinated about the age of 25 at the earliest to form principles integrating abstract systems."
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