Earl Miller is the Picower professor of Neuroscience at MIT. His paper, “An Integrative Theory of Prefrontal Cortex Functionâ€, has been designated a Current Classic as among the most cited papers in Neuroscience and Behavior. He use fMRI and implanted microelectrodes in humans and monkeys.
We talked about top down and bottom up brain functions and how they apply to brain dysfunction and optimal fuctioning.
::::::::
Earl Miller is the Picower professor of Neuroscience at MIT. His paper, "An Integrative Theory of Prefrontal Cortex Function", has been designated a Current Classic as among the most cited papers in Neuroscience and Behavior. He use fMRI and implanted microelectrodes in humans and monkeys.
We talked about top down and bottom up brain functions and how they apply to brain dysfunction and optimal fuctioning.
Earl K. Miller, Ph.D. may be one of the most widely covered neuroscientists,
media-wise, with his work and wisdom covered by the Washington Post, NY Times, Scientific American, Harvard Business Review, ABC News, The Scientist, MSNBC, Boston Globe, Financial Times, Discover, USA Today and many more.
The is the Picower Professor of Neuroscience, Associate Director, The Picower Institute for Learning and Memory
The
Miller Lab uses experimental and theoretical approaches to study the
neural
basis of cognition. We investigatehow categories, concepts, and rules
are learned, mental flexibility, how attention is focused, and, more
generally, how the brain coordinates goal-directed thought and action.
Our goal
is toconstruct more detailed, mechanistic accounts of how executive
control is implemented in the brain and its dysfunction in diseases
such as
autism, schizophrenia, and attention deficit disorder.
The Picower Institute for Learning and Memory and
Department of
Brain and Cognitive Sciences at the
MASSACHUSETTS INSTITUTE OF
TECHNOLOGY
ekmiller@mit.edu www.ekmiller.org
Notes and some transcription from the interview:
Generally, when we talk about top down and bottom up in the brain,
in a we're talking about raw sensory input-what's out there in the
outside world-- that's bottom up.
And top Down, is the knowledge
you use to decide what's important in the outside world, what decisions
you make based on those sensory inputs.
deciding
what's important to pay attention to.
In bottom up we're talking
about the raw information in the outside world and in top down we're
talking about the knowledge we have in our head in order to act on that
information.
Study the electrical activity of the brain nd look
at how the brain processes bottom up sensory inputs and then uses
acquired knowledge to filter things out
Hierarchical signals
that control sensory inputs come from the part of the brain called the
pre-frontal cortex behind the forehead on the right side of your face--
executive part of the brain. processes.
Where top information
comes from in the brain-- come from pre-frontal cortex. Synthesizes all
the information coming into the brain and decides what's important.
Cure
brain diseases where executive brain control-- where decision making
is disfunctional.
Executive
On thing wehre there is Real
interplay between top down and bottom up in the world today. 100 years
ago there was a lot less distraction than there are now. It was
relatively easy to decide what to pay attention to because there weren't
many alternatives. IN todays day and age, we have all sorts of things
vying for our attention. We have TV, the internet, our hand held
devices
So it takes much more top-down control to deal with the
complex, dynamic demanding world we're in now.
Many people have
dysfucntions with that. Many people have trouble with focus and staying
on task, filtering out distractions and getting side-tracked.
Our
ultimate goal is to find out what parts of the brain are responsible
for top down control and fix that in people who need it strengthened.
Rob
What are some examples of disease or disfunction.
ADHD is a
primary on-- people who have trouble staying keeping focused, people who
are easily distractable. There also Decision making problems...
People
who have normal cognition can keep goals on track. Some people with
prefrontal cortex problems lose sightof the goals, the context, of the
big picture and their minds are buffetted by the bottom up sensory
inputs and they have very little top down control-- lose the forest--
the big picture, and get lost in the trees.
Rob: My experience
with neuroscience, the way the mind works has taught me that there's a
need for balancing taking place
Earl: Absolutely'
Rob: So
you need the bottom up. Are there also problems with the ways that
information comes in from the bottom up?
Earl: Well you can have
certain types of impairments-- blindness or deafness or more subtle
examples where some people have trouble recognizing faces. And that's an
example of a deficit in a bottom-up sensory input. The main thing we're
hitting on is the balance, just as you described. THere's a balance in
top down and bottom up. There's always an optimal way of balancing the
two.
He describes a theory on balancing top down and bottom up
considerations-- that there are two parts of the brain involved--
Pre-frontal cortex (PFC) largest part and most developed part in humans.
for top down and it interacts with more primitve brain structures-- the
basal ganglia-- are very primitive brain structures-- even reptiles
have basal ganglia The basal ganglia are involved in learning important
details about the outside world, assigning value to all the things
around us. And they do so by assigning value to individual things,
individual details of everyday experience. .
PFC takes all details
learned by the more primitive basal ganglia and puts it together into
the big picture-- the big idea about what's going on, so you have a
better idea of what sort of goals are available out there, what sort of
behaviors you have to engage in to attain those goals, botht the long
term and shor term.
We think normal cognition is the balanace
between these more detail oriented primitive structures of the brain
that assign value to the details of the things around us and the PFC is
involved in getting the big picture.
When the Bottom-up
Brain goes out of whack; OCD, Autism
And in some case this
system can go out of whack. If the basal ganglia becomes too strong
relative to the PFC, if it does it's job too efficiently, then you have a
brain that's oriented towards details and misses the big picture.
Rob:
LIke OCD?
Earl: Exactly. OCD involves Dysfunction in the frontal
lobes, the PFC and basal ganglia. And that's a case where the brain
focuses on particular details and gets caught in a rut.
Now, other
examples of the brain where imbalance is dysfunctional may be the
autistic brain. In the brains of autistics, they figuratively cannot see
the forest from the trees. They focus on every little detail of
everyday life. So, for example, one thing that parents of autistic kids
will report is that they'll painstakingly teach their kids to do things o
their own, like brush their teeth. Then one day they'll come home with a
new toothbrush that's a different color, like a blue toothbrush instead
of a red toothbrush and the kid completely falls apart. It's almost as
if they're learning things all over again just because a little,
irrelevant details of the toothbrush have changed-- it's color. You and
I know that the color of the toothbrush doesn't matter. It's what the
toothbrush does. But in an autistic brain every little detail is equally
important as every other detail, so if something new happens, they
completely fall apart-- almost like they're seeing it for the very first
time. If you have a brain like that, every time... you look at
something from a new angle, ... it becomes like a new learning
experience, instead of picking up where they left off and that's
probably why you see such severe learning disabilities in a brain like
that.
Rob: So an autistic has a predominance of the basal
ganglia effect and the PFC is not up to doing the integration and
interpretation?
Earl: Yes. THis is just a hypothesis based on
data and tests done over the years-- and we're now doing a direct test
of this hypothesis. And there's lots of supporting information. And the
general idea is that , what we call plasticity mechanisms in the brain--
the mechanisma of the brain that allow for re-wiring-- are too strong
in the basal ganglia. And the basal ganglia learn the details too well
and the basal ganglia overwhelm the ability of the prefrontal cortex to
get the big picture.
Normal
cognition between more detail oriened, primitive structures.... and
prefrontal cortex. In some cases the balance becomes out of whack.
OCD--
Autistic Brain cannot see the forrest for the trees. Focus on
all the details in everyday life.
brushing teeth.
temple
grandin
Plasticity mechanisms are too strong in the basal
ganglia
brain games-- for improvng attention, multitasking--
computer games to improve your brain.
with better understanding
the
grassroots, the outside world, sort of form it's structure. 16:00
Overactive
pre-frontal cortex-- some are more pre-frontal, more goal oriented.
Others just live for the day. That's goign to be dysfunctional.
Personality
disorders; too rigid, totalitarian, otherwise very driven and
opinionated.
Stimulus bound behavior.... 23
Delusions,
schizophrenia are top down disorders.
Using fMRI,
micro-electrodes montior activity of individual neurons. with monkeys
AND humans.
main difference in human and animal brain is size of
prefrontal cortex 1/3 of cortex in humans 16% in monkeys, 4-5% in
other animals.
Humans have a lot of folds in brain which add surface
area.
Biggest difference between human mind and animal is human
mind gets big picture easily.
brain synchrony "favored"
38:00 phase synchrony line up thoughts and organize them with
different synchronies.
sequential thinking
Authors Bio:One theme has run through my work for the past 40 plus years-- a desire to play a role in waking people up, raising their consciousness and empowering them.
I was the organizer founder of the Winter Brain, Optimal Functioning and Positive Psychology and StoryCon Meetings and president of Futurehealth, Inc., with interests in Positive Psychology as well as being involved in the field of biofeedback/neurofeedback since 1972.
see my more detailed bio, reflecting my work in biofeedback, here.
In 2003 I founded www.OpEdNews.com , where I've written over 1800 articles and have published over 100,000 other people's writings, with the goal of raising people's consciousness in political and activist ways.