TED TALK: Michael Merzenich on re-wiring the brain
Michael Merzenich on re-wiring the brain
The brain is constructed for change. It confers on us the ability to do things to tomorrow that we can’t do today, things today that we couldn’t do yesterday.
The brain is born stupid.
At birth, there is no indication that there is any cognitive ability. Infants don’t respond much, actually there is no indication that there is a real person on board. Movement in infants is also very primitive. It will take months for the infant to mature into the time in which the individual can motate in the world.
The brain is an exquisitely adaptable machine.
Beyond age 4, the brain is able to store, record, can fastly retrieve the meanings of thousands of words or objects, actions and their relationships in the world, and those relationships can be constructed in hundreds of thousands, potentially millions of ways. By this age the brain controls a very refined set of perceptual abilities, and has a growing repertoire of cognitive skills.
The brain is a thinking machine, at this time there is no question that there is actually a person on board that is able to substantially control its own self-development, has the capacity to control movement. At that point, movement has advanced to a point where it can actually control movement simultaneously in a complex sequence of ways (soccer).
Our individual skills and abilities are very much shaped by our environments, and that environment extends into our contemporary culture, the thing our brain is challenged with. What we do in our personal evolution is build up a large repertoire of specific skills and abilities that are specific to our own individual histories. This results in a wonderful differentiation in humankind in a way in fact no two of us are quite alike. Every one of us has a different set of acquired skills and abilities that are derived out of the plasticity, the adaptability of this remarkable adaptive machine. An adult brain is constructed from a wealth of experience and knowledge. In an adult brain we would have built up a large repertoire of mastered skills and abilities that we can perform automatically from memory. This defines us as acting, moving, thinking creatures.
We study remodeling by engaging laboratory animals like rats or monkeys to learn new skills and abilities, and we try to track the changes that occur as the new skill or ability is acquired. Human brain remodeling is also studied today from infancy to adulthood and old age.
Example: Engage a rat to learn a new skills or abilities that might involve it using its paw to master particular manual grasp behavior
Example 2: Examining a child acquire the sub-skills, or the general overall skills of accomplishing something like mastering the ability to read,
Example 3: Looking at an older individual master a complex set of abilities that might relate to reading musical notation or performing the mechanical acts of musical performance.
From such palstityc studies, we conclude that there are two great epochs of brain plasticity.
The two great epochs of brain plasticity.
1. The Critical period. The period the brain is setting up its initial form, its basic processing machinery. This is a period of dramatic change, such that it doesn’t take learning to drive the initial differentiation of the machinery of the brain.
Example: In the sound domain, mere exposure to sound drives the differentiation of the auditory cortex. The brain is actually at the mercy of the sound environment in which it is reared.
Experiment: Rearing an animal in an environment in which there is meaningless dumb sound ( A repertoire of sound the scientist makes up just by exposure to artificially important to the animal and its young brain).
Result: the animals brain sets up its initial processing in a form that’s idealized, within the limits of its processing achievements to represent it in an organized and regularly way.
Sound used doesn’t have to be valuable to the animal.
a. Hypothetically good sound: Sounds that simulate the sounds of a native language of a child.
(im not finished yet, still trying to decode what this amazing scientist is trying to get at)