What makes this experiment so important is that it provides a tool
that directly links neuron activity to action. Perhaps we can now
see something other than noise.
We have been piecing together the physical aspects of the brain for
decades now with decent success. Yet it has also been unsatisfactory
in just the way that tearing apart a computer is without hearing
about software. We are now looking at the software make a decision.
This is the real beginning for understanding the workings of the
brain. Let us apply this tool to the human brain as quickly as
possible. The monkey brain is hardly less complex so no advantage
exists whatsoever starting there and the human brain already knows
how to report.
Scientists Read
Monkeys' Minds, See What They're Planning to Do Before They Do it
By Clay
DillowPosted 07.23.2012 at 1:30 pm
How To Construct a
'Circle-Out' Experiment (BYO Monkey) MORAN/PEARCE via WUSTL
Neurologists working
with monkeys at Washington University in St. Louis to decode brain
activity have stumbled upon a rather surprising result. While working
to demonstrate that multiple parameters can be seen in the firing
rate of a single neuron (and that certain parameters are embedded in
neurons only if they are needed to solve the immediate task), they
also found that they could read their monkeys’ minds.
This isn’t exactly
ESP, but it is really interesting. The researchers came to find out
that by analyzing the activity of large populations of neurons, they
could discover what actions the monkeys were planning before they
made a single motor movement. By monitoring neural activity, the
researchers could essentially see what the monkey was thinking about
doing next.
This discovery
occurred largely because the two monkeys involved in the experiment
had already demonstrated very different cognitive styles. One is a
bit hyperactive, eager to begin and complete each task even before
being given the signal to begin. The other is more methodical,
waiting for the entire breadth of the task to be revealed before
making a motion.
The tasks involved
were so-called “center-out tasks” in which a monkey or some other
subject must place a hand at the center of a field (a tabletop or
some surface) and then move it from this center location to another
location placed in the area around the center. To plan this movement,
the brain needs to know simply where its hand is located (at the
center), where the target locations is (somewhere on the surface away
from center), and the velocity vector the hand will follow (what path
the hand will take to move from starting place to target). These can
all be measured in the neural activity of the brain.
When the path between
center and target locations is unimpeded, this is relatively
straightforward in terms of neural activity. But when the the
researchers introduced obstacles that would pop up between the center
and the target like whack-a-moles, the neural activity of the two
monkeys began to show interesting differences.
The impatient monkey
(known as subject H) couldn’t wait to reach for the target and
planned to reach directly for it, so when the obstacle popped up his
directional vector shortened and then rotated to find a way around
the obstacle. Methodical monkey (subject G), however, would wait for
the obstacle to present itself before moving, and only then begin to
plan its directional vector to go around the obstacle and reach the
target. In cases where the target was unimpeded, it paid to jump the
gun. But when an obstacle was presented, Methodical Monkey reached
the target faster.
In other words, the
two monkeys showed completely different strategies for reaching the
target--strategies that the researchers could see unfolding in the
neural activities of their brains beforehand. They could see what the
monkeys were planning before they did it--which is pretty amazing
from a neuroscience standpoint.
The study was
published in the July 19 advance online edition of Science
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