Albert Einstein proposed theories of relativity that transformed
physics. About 50 years ago, Francis Crick and James Watson discovered
the DNA (deoxyribonucleic acid) properties that transformed genetics.
Neuroscientists are now searching for a universal theory of brain
systems and processes that could perhaps be represented by an equation,
such as Einstein's e=mc2, or a simple model like DNA's double helix.
The problem
is that our brain is a complex time space movement system that carries
out many different functions as it remembers the past, responds to the
present, and predicts the future-and not only about things and events
that are here, but also over there. And for good measure, it can also
imagine the currently unimaginable-and simultaneously regulate such
survival functions as respiration and circulation. Busy, busy, busy.
Although each
human brain is unique, all have common characteristics. We've carefully
observed each other for many millennia, and so can often predict the
behavior that results from another person's decisions. Further,
dramatic advances in neuroimaging technology can now provide increased
credible information on the underlying neurobiology of such decisions.
So perhaps it's not out of the range of possibility that someone could
eventually represent our awesomely complex brain with an eloquently
simple equation or model.
The cover story
of the May 28 New Scientist magazine describes the intriguing attempt
by neuroscientist Karl Friston and colleagues at University College
London to develop a universal brain theory that could be represented by
a mathematical formula.
Friston views our brain
as a probability system that constantly predicts what might occur in an
ambiguous environment, and that then adjusts its predictions on the
basis of new relevant sensory information. The basic task: Reduce
prediction errors. For example, imagine that my peripheral vision
registers a moving object while you and I are conversing. I might
ignore it, assuming that it's non-threatening and less important than
our conversation. That may well be the case if I'm familiar with the
setting we're in, and know the typical movement patterns within it.
But it's also
possible that I'm wrong, especially if we're in a strange setting. To
ignore the moving object might thus prove harmful. The most efficient
way to gather more information on the nature of the moving object is to
briefly put our conversation on hold, turn my head, and shift my focus
to the moving object. The added information will allow me to update my
prediction about the relative importance of our conversation and the
moving object.
Successful
problem solving thus depends on the quantity and quality of relevant
information combined with our prior experiences with the type of
challenge we're confronting. Considerable relevant information and
experience typically lead to a successful response. Limited relevant
information and/or experience often lead to an unsuccessful response.
Friston hopes to represent the predictive roles of experience and
information in an equation.
Two earlier Brain Connection columns focused on Jeff Hawkins' and Malcolm Gladwell's non-technical explorations of this general issue.
A Mystery Novel
I had an experience a few days ago that might help to explain how experience and information interact in prediction:
I read a very
engaging mystery novel that I now have totally forgotten in terms of
its title, characters, plot, and resolution. Why could something that
completely engrossed me for six or so hours disappear so quickly and
completely? Friston's beliefs about cognition help to explain it-and
also why forgetting is often such a useful brain property.
I've read
other mysteries so I knew the genre, but not the specifics that would
unfold in this novel. After about 30 pages, I had a good sense of the
plot and characters, and so my conscious problem solving system began
its continuing attempts to predict the plot trajectory and outcome. But
since I had only a very limited amount of information at that point, I
didn't have a lot of confidence in my predictions. I thus had to read
on (gather more relevant information) in order to reduce the potential
error rate of my early predictions. The author helped me to constantly
adjust my beliefs to emerging new realities by writing a page-turner
that maintained my interest while it enhanced my information base. But
the author also sent me down blind alleys with misleading information.
I thus had to keep my wits about me to separate helpful from useless
information.
So what was
occurring was a constant mental comparison of my knowledge of how the
world works with the specifics of the story that was unfolding on the
pages.
By the time I got close
to the end, I had a pretty good sense of how the novel might turn out
(because the increased information enhanced my predictive
capabilities), but I read through to the end to make sure that my
predictions were correct.
Once I knew
the solution, I had no need to remember any of it, since the situation
will never reoccur. My brain pressed the delete button, and the
completely engrossing experience was gone forever. How about that!
I've read
other mysteries so I knew the genre, but not the specifics that would
unfold in this novel. After about 30 pages, I had a good sense of the
plot and characters, and so my conscious problem solving system began
its continuing attempts to predict the plot trajectory and outcome. But
since I had only a very limited amount of information at that point, I
didn't have a lot of confidence in my predictions. I thus had to read
on (gather more relevant information) in order to reduce the potential
error rate of my early predictions. The author helped me to constantly
adjust my beliefs to emerging new realities by writing a page-turner
that maintained my interest while it enhanced my information base. But
the author also sent me down blind alleys with misleading information.
I thus had to keep my wits about me to separate helpful from useless
information.
I now know a
bit more about the mystery novel genre from reading the book, but I
don't really want to know too much, since if I could accurately predict
a novel's resolution after 30 pages, what would be the sense of
continuing with the book (or with life, to extend the metaphor)? It's
thus helpful to have a brain that can predict successful resolutions to
life's continuing challenges-but it's not helpful to have a brain that
could predict with certainty at 30 when and how I will die decades
later.
Note the similarities to
the recent presidential primaries. Many of us were engrossed by them
while they were occurring. The frustration and stimulation that many
felt was probably because of all the uncertainties and blind alleys
that continually emerged with new events. Things didn't develop as
initially predicted or preferred. I suspect though that most of us have
already forgotten much of it as we shift our interests to confront the
similar uncertainties of the general campaign, the next challenge in
our political life.
I can also
think of the totally engrossing football games I watched last fall-and
that I now can't remember the scores of any of them. I can think of
challenging crossword puzzles that are totally forgotten within a few
minutes of completion. If the solution and not the process is the key
element of the enterprise, we'd say at completion, "Well, now that I
know the correct answer, I'll erase it the words and do it again."
I've read
other mysteries so I knew the genre, but not the specifics that would
unfold in this novel. After about 30 pages, I had a good sense of the
plot and characters, and so my conscious problem solving system began
its continuing attempts to predict the plot trajectory and outcome. But
since I had only a very limited amount of information at that point, I
didn't have a lot of confidence in my predictions. I thus had to read
on (gather more relevant information) in order to reduce the potential
error rate of my early predictions. The author helped me to constantly
adjust my beliefs to emerging new realities by writing a page-turner
that maintained my interest while it enhanced my information base. But
the author also sent me down blind alleys with misleading information.
I thus had to keep my wits about me to separate helpful from useless
information.
I now know a
bit more about the mystery novel genre from reading the book, but I
don't really want to know too much, since if I could accurately predict
a novel's resolution after 30 pages, what would be the sense of
continuing with the book (or with life, to extend the metaphor)? It's
thus helpful to have a brain that can predict successful resolutions to
life's continuing challenges-but it's not helpful to have a brain that
could predict with certainty at 30 when and how I will die decades
later.
References:
Gladwell, M. (2005) Blink: The power of thinking without thinking. 
Hawkins, J. and Blakeslee, S. (2004) On intelligence: How a new understanding of the brain will lead to the creation of truly intelligent machines
Huang, G. (May 31, 2008). "Essence of Thought" New Scientist. Pages 30-33.
University of Oregon. He focuses on the educational implications of new
developments in science and technology and has written several books
and over 150 journal articles. His most recent books are The Adolescent Brain: Reaching for Autonomy (2007, Corwin Press), How to explain a brain: An educator's handbook of brain terms and cognitive processesA
biological brain in a cultural classroom: Enhancing cognitive and
social development through collaborative classroom management(2003,
Corwin Press. second edition). The Education Press Association of
America gave him three Distinguished Achievement Awards for his
published syntheses of cognitive science research. He has made over
1400 conference and in-service presentations on educationally
significant developments in brain/stress theory and research. (2004, Corwin Press),and
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