which we all have residing in our skulls reminds me of an aphorism of a comment of woody allen to ask about what is the very best thing to have within your skull and it's this machine
and it's constructed for change it's all about change it confers on us the ability to do things tomorrow that we can't do today things today that we couldn't do yesterday
and of course it's born stupid
the last time you were in the presence of a baby this happens to be my granddaughter
when she popped out despite the fact that her brain had actually been progressing in its development for several months before on the basis of her experiences in the
she had very limited abilities as does every infant
at the time of normal natural full term birth
no real indication that there is any real thinking going on in fact there is little evidence that there is any cognitive ability in a very young infant
and they can only in a very primitive way and in a very limited way control their movements it would be several months before
do something as simple as reach out and grasp under voluntary control an object and retrieve it usually to the mouth
and we see a long steady progression of the evolution from the first wiggles
to rolling over and sitting up and crawling standing walking before we get to that magical point in which we can motate in the world
and yet when we look forward in the brain we see really remarkable advance
the brain controls very refined perceptual abilities and it actually has a growing repertoire of cognitive skills this brain is very much a thinking machine
it has a person on board and in fact at this age it is substantially controlling its own self development
and by this age we see a remarkableevolution in its capacity to control movement
now movement has advanced to the point where it can actually control movementsimultaneously in a complexsequence in complex ways as would be required for example for playing a complicated game like soccer
now this boy can bounce a soccer ball on his head
and where this boy comes from sao paulo brazil about forty percent of boys of his age have this ability
that our individual skills and abilities are very much shaped by our environments that environment extends into our contemporaryculture the thing our brain is challenged with
because what we've done in our personal evolutions is build up a large repertoire of specific skills and abilities that are specific to our own individual histories
and in fact they result in a wonderful differentiation in humankind in the way that in fact no two of us are quite alike
every one of us has a different set of acquired skills and abilities that all derive out of the plasticity the adaptability of this really remarkable adaptive machine
in an adult brain of course we've built up a large repertoire of mastered skills and abilities that we can perform more or less automatically from memory
now we study this as the nerdy laboratory university based scientists that we are
by engaging the brains of animals like rats
to engage them in learning new skills and abilities and we try to track the changes that occur as the new skill or ability is acquired
in fact we do this in individuals
of any age in these different species that is to say from infancies
infancy up to adulthood and old age
so we might engage a rat for example to acquire a new skill or ability that might involve the rat using its paw to master particular manual grasp
might look in an older individual who has mastered a complex set of abilities that might relate to readingmusical notation or performing the mechanical acts of performance that apply to musical performance
from these studies we defined
the plastic history of the brain
the first great epoch is commonly called the critical period
in which it doesn't take learning per se to drive
all it takes for example in the sound domain is exposure to sound
so for example i can rear an animal in an environment in which there is meaningless dumb sound
that i make just by exposureartificially important to the animal and its young brain and what i see
is that the animal 's brain sets up its initial processing of that sound in a form that's idealized within the limits of its processing achievements to represent it in an organized and orderly way
the sound doesn't have to be valuable to the animal
i could raise the animal in something that could be hypothetically valuable
like the sounds that simulate the sounds of a native language of a child and i see the brain actually develop a processor that
specialized for that complex array a repertoire of sounds it actually exaggerates their separateness of representation in multi dimensional neuronal representational terms
or i can expose the animal to a completely meaningless and destructive sound i can raise an animal under conditions that would be equivalent to raising a baby under a moderately loud ceiling fan
in the presence of continuous noise
and when i do that i actuallyspecialize the brain
to be a master processor for that meaningless sound and i frustrate its ability to represent any meaningful sound as a consequence
such things in the early history of babies occur in real babies and they account for for example the beautiful evolution of a language specific processor in every normally developing
and do they also account for development of defective processing in a substantial population of children who are more limited as a consequence in their language abilities at an older age
in this early period of plasticity the brain actually changes outside of a learning context
i don't have to be paying attention to what i hear
the input doesn't really have to be meaningful
begin to operate on it in a selective way
in the next great epoch of life which applies for most of life
the brain is actually refining its machinery
as it masters a wide repertoire of skills and abilities and in this epoch which extends from late in the first year of life
to death it's actually doing this under behavioral control
and it's focusing on skill after skill or ability after ability under specific attentional control it's a function of whether a goal in a behavior is achieved or whether the individual is rewarded in the behavior
this is actually very powerful
this lifelongcapacity for plasticity for brain change is powerfully expressed it is the basis of our real differentiation one individual from another
you can look down in the brain of an animal that's engaged in a specific skill and you can witness or document this change on a variety of levels so here is a very simple experiment it was actually conducted about five years ago
the monkeyactually mastered the task in about seven hundred practice tries
so in the beginning the monkey could not perform this task at all it had a success rate of about one in eight tries
the monkey gradually developed a strategy and seven hundred or so tries later the monkey is performing it flawlessly never fails he 's successful in his retrieval of food with this tool every time
at this point the task is being performed in a beautifully stereotyped way
very beautifully regulated and highly repeated trial to trial
we can look down in the brain of the monkey and we see that it's distorted
now this is a map down on the surface of the brain in which in a very elaborate experiment we've reconstructed the responses location by location in a highly detailed response mapping of the responses of its neurons
we see here a reconstruction of how the hand is represented in the brain
we look at the selectivity of responses in the cortex of the monkey we see that the monkey has actually changed the filter characteristics which represents input from the skin
of the fingertips that are engaged in other words there is still a single simple representation of the fingertips in this most organized of cortical areas of the surface of the skin of the body
monkey has like you
and yet now it's represented in substantially finer grain the monkey is getting more detailed information from these surfaces and that is an unknown unsuspected maybe by you
part of acquiring the skill or ability
now actually we've looked in several different cortical areas in the monkeylearning this task and each one of them changes in ways that are specific to the skill or ability
so for example we can look to the cortical area
we look in cortical areas that control specific movements and the sequences of movements that are required in the behavior and so forth they are all remodeled they all become specialized for the task at hand there are fifteen or twenty cortical areas that are changed specifically
when you learn a simple skill like this and that represents in your brain really massive change
it represents the change in a reliable way of the responses of tens of millions possibly hundreds of millions of neurons in your brain
it represents changes of hundreds of millions possibly billions of synaptic connections in your brain
this is constructed by physical change and the level of construction that occurs
what it's all about is the selective representations of things that are important to the brain
because in most of the life of the brain this is under control of behavioral context it's what you pay attention to it's what's rewarding to you it's what the brain regards itself as positive and important to you
and that underlies your specialization that is why you in your many skills and abilities are a unique specialist
a specialist that's vastly different
in your physical brain in detail
the brain of an individual one hundred years ago
in the details from the brain of the average individual one thousand years ago
now one of the characteristics of this change process
is that information is always related to other inputs or information that
in immediate time in context and that's because the brain is constructing representations of things that are correlated in little moments of time and that relate to one another in little moments of successive time
the brain is recording all information and driving all change in temporal context
or yourself as the actor yourself as the thinker yourself as the mover
you you are constructed your self is constructed
from these billions of events
this is a marvelously constructed
thing that results in individual form
now we've used this research to try to understand not just how a normal person develops and elaborates their skills and abilities but also try to understand
the origins of impairment
differences or variations that might limit the capacities of a child or an adult i'm going to talk about using these strategies
actually design brain plasticity based
to drive corrections in the machinery of a child
that increases the competence of the child as a language receiver and user and thereafter as a reader
i'm going to talk about experiments that involveactually using this brain science first of all to understand how it contributes to the loss of function as we age then by using it in a targeted approach
to recover function in old age
that have early language impairments and that are going to struggle to learn to read is that their language processor is created in a defective form
and the reason that it rises in a defective form is because early in the baby 's brain 's life
the machine process is noisy
it's that simple it's a signal to noise problem
i might say the noise problem could also occur on the basis of information provided
in the world from the ears
if any those of you who are older in the audience know
that when i was a child we understood that a child born with a cleft palate
with what we called mental retardation
we knew that they were going to be slow cognitively
we knew they were going to struggle to learn to develop normal language abilities
and we knew that they were going to struggle to learn to read
most of them would be intellectual and academic failures
that's disappeared that no longer applies
about thirty five years ago that if you simply fix the problem early enough
when the brain is still in this initial plastic period so it can set up this machinery adequately in this initial set up time in the critical period
none of that happens what are you doing by operating on the cleft palate to correct
which have had them reliably full
every sound the child hears uncorrected is muffled it's degraded
the child 's native language is such a case is not english
it's not japanese
and then the child is stuck with it
there are many inherited faults that can make it noisier
and the native language for a child with such a brain
it's not english it's noisy
not normal a different strategy
by a machine that has different space constants and you can look in the brain of such a child and record those time constants they are about an order of magnitude longer
about eleven times longer in duration on average than in a normal child
abnormal neurology
these children increasingly in evaluation after evaluation in their operations in language and their operations in reading we document that abnormal neurology
the point is is that you can train the brain out of this a way to think about this is you can actually re refine the processing capacity of the machinery by changing
changing it in detail it takes about thirty hours on the average and we've accomplished that in about four hundred and thirty thousand kids today
actually about fifteen thousand children are being trained as we speak
and actually when you look at the impacts the impacts are substantial so here we're looking at the normaldistribution what we're most interested in is these kids on the left side of the distribution this is from about three thousand children you can see that most of the children on the left side of the distribution are moving into the middle or the right
this is in a broad assessment of their language abilities this is like an iq test for language the impact in the distribution if you trained every child in the united states would be to shift the whole distribution to the right and narrow the distribution
this is a substantially large impact think of a classroom of children in the language arts think of the children on the slow side of the class
we have the potential to move most of those children to the middle or to the right
in addition to accurate language training
it also fixes memory and cognition speech fluency and speech production
and an important language dependent skill is enabled by this training that is to say reading and to a large extent it fixes the brain
you can look down in the brain of a child
in a variety of tasks that scientists have at stanford
and mit and ucsf and ucla and a number of other institutions and children operating in various language behaviors
can also take the same approach
to address problems in aging
noise is increasing in the brain and learning modulation and control is deteriorating and you can actually look down on the brain of such an individual and witness a change in the time constants and space constants with which for example the brain is representing language again
just as the brain came out of chaos at the beginning it's going back into chaos in the
this results in declines in memory
in cognition and in postural ability and agility
it turns out you can train the brain of such an individual this is a small population of such individuals train equally intensively for about thirty hours these are eighty to ninety year olds
to the middle or the right side of the distribution
at risk for senility more or less immediately
are now in a protected position
my issues are to try to get to rescuing older citizens more completely and in larger numbers because i think this can be done in this arena on a vast scale
and the same for kids my main interest is how to elaborate this science to address other maladies i'm specifically interested in things like autism and cerebral palsy
your issues as it relates to this science
is how to maintain your own high functioning learning machine
and of course a well ordered life
in which learning is a continuous part of it is key
but also in your future is brain aerobics
get ready for it it's going to be a part of every life not too far in the future
just like physical exercise is a part of every well organized life in the contemporary period the other way that we will ultimately come to consider this
literature and the science that is
it's under your control
that your happiness your well being your abilities your capacities
and you're the responsible agent and party
of course a lot of people will ignore this advice it will be a long time before they really understand
now that's another issue and not my fault okay thank you
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