Darwin VII
Unlike a robot, Darwin VII is an
autonomous "being" which starts with a naive brain and learns from its
own experience, connected to a realistic model of the mammalian brain
that is simulated on a multiprocessor computer
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Darwin VII is a Brain-Based Device that is used as a tool to help study the
brain. Darwin VII starts out naive and learns from its own
experience. It is connected to a realistic model of a brain, which
is simulated on a network of powerful computers. All of Darwin VII's
behaviors are controlled by the activity of its brain cells, allowing
researchers a unique window into how the human brain may work. Darwin VII
can interact with its environment in several ways: by sensing light,
sound and taste, and by moving around and grabbing objects.
As Darwin VII roams around the lab, the images it captures through
a video
camera are sent through a wireless connection to its brain running
inside a computer. The brain tries to make sense of the image through
the activity of its neurons. Then the brain triggers a motor command,
which is relayed to Darwin VII's body.
When the researchers activate Darwin VII, it begins a "run" with a
naive
brain. It has an inborn preference for light and a predisposition for a
certain taste, but no other experience or programming.
As it explores its environment, Darwin VII will encounter a small
black
block with a blob or stripe on the top. Since it is attracted to light,
it will steer toward the block and pick it up. When it grabs the
striped block with its metal gripper, it gets a charge of current. In
the simulated brain, this conductivity is registered as good taste.
Blocks with blobs, on the other hand, do not give a charge and
correspond to bad taste. As Darwin VII's gripper holds the block, the brain
simulation associates the taste of the block with the pattern that it
sees. Through the brain simulation, Darwin VII not only learns what each
block looks like, but which blocks taste good and which taste bad.
After learning these things, it will no longer pick up the bad tasting
blocks. It will approach the blocks, and after seeing the pattern of
the blocks, Darwin VII will now remember the associated taste. If Darwin VII
thinks it tastes good it will pick up the block and if it thinks it
tastes bad it will avoid the block.
To date, The Institute's work has yielded revealing insights,
e.g. into
the importance of self-generated movement in the aquisition of
perceptual capability and the almost universal role of value systems in
adaptaion and learning.
The Institute's researchers believe that it is impossible to
study the
brain or a part of it in isolation. Feeding static data to the brain
simulation running on a computer does not capture the complexity of the
processing that the brain is required to do. Using Darwin VII we can perform
tests with all of the noise and sophistication of the real world and
still record the activity from the entire brain, something that is
extremely difficult to do with live animals.
What Darwin VII "does"
- navigates through its environment
- senses obstacles and avoids bumping into them
- approaches objects after "seeing" them from a
distance
- grabs objects with its gripper
- tastes objects
- rejects or avoids objects that it has learned will
taste bad
Darwin VII Photos
Click on
any photo for a larger image. All photos on this web page are used with
the permission of Newsmakers
online photo service.
Chief engineer
James Snook performs "brain surgery"
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Neuroscientist Jeff
Krichmar, Ph.D., (left) and chief engineer James Snook look over Darwin VII.
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Darwin VII picks up an object it found to see if it thinks it "tastes good"
using its thinking brain as neuroscientist Jeff Krichmar, Ph.D, watches.
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Darwin VII Videos
Darwin VII's Behavior and Brain Response
During Learning
These movie clips show Darwin VII in action during behavioral experiments
and, to the right of Darwin VII, activity of selected neural areas in the
simulation (R, top left; IT, top right; A1, bottom left; Mave, bottom
right, left side; Mapp, bottom right, right side). Each pixel in a
selected neural area represents a neuronal unit and activity is
normalized in a range from no activity (dark blue) to maximal activity
(bright red). During each movie clip Darwin VII first approaches an
appetitive block and then an aversive block. More details of this
experiment can be found in our recent publications.
- View
Darwin VII during an early visual learning trial (mpeg,
24MB)
Darwin VII upon early encounter with blocks having visual patterns. In this
early conditioning trial, Darwin VII is shown picking up and "tasting" both
the appetive and aversive block. Activity in IT is insufficient, but
activity in the taste system is sufficient to drive activity in the
motor behavior neural area (Mave or Mapp) above the behavioral
threshold.
- View
Darwin VII after visual conditioning (mpeg, 19MB)
Darwin VII upon the tenth encounter with blocks having visual patterns.
After primary conditioning with visual stimuli, activity in area IT is
sufficient to drive the Mave or Mapp neuronal units above the
behavioral threshold triggering a motor response to taste an appetitive
block and avoid "tasting" an aversive block.
- View
Darwin VII after auditory conditioning (mpeg, 18MB)
Darwin VII upon the tenth encounter with blocks having only auditory cues.
The stimulus blocks shown in the figure beeped, but had a pattern made
up of small black and white shapes that was high contrast enough to
evoke a visual tracking response, but did not have enough of a pattern
to evoke a response in IT. After primary conditioning with auditory
stimuli, activity in area A1 is sufficient to drive the Mapp or Mave
neuronal units above the threshold to trigger a behavioral response.
Darwin VII In Action
This film clip shows Darwin VII in action. Darwin VII is born with certain
instincts: he avoids hitting obstacles, he approaches high contrast
objects, and he gets good value or taste from conductive objects. In
the film clip, the blocks with striped patterns are conductive. Darwin VII
learns on his own that the striped blocks are good tasting and the blob
patterned blocks are bad tasting. In other words, Darwin VII has learned to
associate a taste with a visual pattern. After about 10 samples of each
block, Darwin VII learns to avoid tasting the blob patterned blocks.
Darwin VII In The News
This film clip shows a short news piece that gives a nice overview of
the NOMAD project. It was aired by KGTV, a
San Diego ABC affiliate, on May 4th, 2000. This movie clip is used with
permission of KGTV.
For more information, contact Jeff Krichmar
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