Chips Coming To A Brain Near You
By Lakshmi Sandhana - Wired News - 22 October 2004
In this era of high-tech memory management, next in line to get
that memory upgrade isn't your computer, it's you.
Professor Theodore W. Berger, director of the Center for Neural
Engineering at the University of Southern California, is creating
a silicon chip implant that mimics the hippocampus, an area of the
brain known for creating memories. If successful, the artificial
brain prosthesis could replace its biological counterpart, enabling
people who suffer from memory disorders to regain the ability to
store new memories.
And it's no longer a question of "if" but "when."
The six teams involved in the multi-laboratory effort, including
USC, the University of Kentucky and Wake Forest University, have
been working together on different components of the neural prosthetic
for nearly a decade. They will present the results of their efforts
at the Society for Neuroscience's annual meeting in San Diego, which
begins Saturday.
While they haven't tested the microchip in live rats yet, their
research using slices of rat brain indicates the chip functions
with 95 percent accuracy. It's a result that's got the scientific
community excited.
"It's a new direction in neural prosthesis," said Howard
Eichenbaum, director of the Laboratory of Cognitive Neurobiology
at Boston University. "The Berger enterprise is ambitious,
aiming to provide a prosthesis for memory. The need is high, because
of the prevalence of memory disorder in aging and disease associated
with loss of function in the hippocampus."
Forming new long-term memories may involve such tasks as learning
to recognize a new face, or remembering a telephone number or directions
to a new location. Success depend on the proper functioning of the
hippocampus. While this part of the brain doesn't store long-term
memories, it re-encodes short-term memory so it can be stored as
long-term memory.
It's the area that's often damaged as a result of head trauma, stroke,
epilepsy and neurodegenerative disorders such as Alzheimer's disease.
Currently, no clinically recognized treatments exist for a damaged
hippocampus and the accompanying memory disorders.
Berger's team began its research by studying the re-encoding process
performed by neurons in slices of rat hippocampi kept alive in nutrients.
By stimulating these neurons with randomly generated computer signals
and studying the output patterns, the group determined a set of
mathematical functions that transformed any given arbitrary input
pattern in the same manner that the biological neurons do. And according
to the researchers, that's the key to the whole issue.
"It's an impossible task to figure out what your grandmother
looks like and how I would encode that," said Berger. "We
all do a lot of different things, so we can't create a table of
all the things we can possibly look at and how it's encoded in the
hippocampus. What we can do is ask, 'What kind of transformation
does the hippocampus perform?'
"If you can figure out how the inputs are transformed, then
you do have a prosthesis. Then I could put that into somebody's
brain to replace it, and I don't care what they look at -- I've
replaced the damaged hippocampus with the electronic one, and it's
going to transform inputs into outputs just like the cells of the
biological hippocampus."
Dr. John J. Granacki, director of the Advanced Systems Division
at USC, has been working on translating these mathematical functions
onto a microchip. The resulting chip is meant to simulate the processing
of biological neurons in the slice of rat hippocampus: accepting
electrical impulses, processing them and then sending on the transformed
signals. The researchers say the microchip is doing exactly that,
with a stunning 95 percent accuracy rate.
"If you were looking at the output right now, you wouldn't
be able to tell the difference between the biological hippocampus
and the microchip hippocampus," Berger said. "It looks
like it's working."
The team next plans to work with live rats that are moving around
and learning, and will study monkeys later. The researchers will
investigate drugs or other means that could temporarily deactivate
the biological hippocampus, and implant the microchip on the animal's
head, with electrodes into its brain.
"We will attempt to adapt the artificial hippocampus to the
live animal and then show that the animal's performance -- dependent
in these tasks on an intact hippocampus -- will not be compromised
when the device is in place and we temporarily interrupt the normal
function of the hippocampus," said Sam A. Deadwyler, "thus
allowing the neuro-prosthetic device to take over that normal function."
Deadwyler, a professor at Wake Forest University, is working on
measuring the hippocampal neuron activity in live rats and monkeys.
The team expects it will take two to three years to develop the
mathematical models for the hippocampus of a live, active rat and
translate them onto a microchip, and seven or eight years for a
monkey. They hope to apply this approach to clinical applications
within 10 years. If everything goes well, they anticipate seeing
an artificial human hippocampus, potentially usable for a variety
of clinical disorders, in 15 years.
Overall, experts find the results promising.
"We are nowhere near applicability," said Boston University's
Eichenbaum. "But the next decade will prove whether this strategy
is truly feasible."
"There is a big gap in making the microchip work in a slice
preparation and getting it to work in a human being," added
Norbert Fortin, a neuroscientist from the Cognitive Neurobiology
Lab at Boston University. "However, their approach is very
methodical, and it is not unreasonable to think that in 15 to 20
years such a chip could help, to some degree, a patient who suffered
from hippocampal damage."
© Copyright 2004, Lycos, Inc. All Rights Reserved.
In this era of high-tech memory management, next in line to get
that memory upgrade isn't your computer, it's you.
Professor Theodore W. Berger, director of the Center for Neural
Engineering at the University of Southern California, is creating
a silicon chip implant that mimics the hippocampus, an area of the
brain known for creating memories. If successful, the artificial
brain prosthesis could replace its biological counterpart, enabling
people who suffer from memory disorders to regain the ability to
store new memories.
And it's no longer a question of "if" but "when."
The six teams involved in the multi-laboratory effort, including
USC, the University of Kentucky and Wake Forest University, have
been working together on different components of the neural prosthetic
for nearly a decade. They will present the results of their efforts
at the Society for Neuroscience's annual meeting in San Diego, which
begins Saturday.
While they haven't tested the microchip in live rats yet, their
research using slices of rat brain indicates the chip functions
with 95 percent accuracy. It's a result that's got the scientific
community excited.
"It's a new direction in neural prosthesis," said Howard
Eichenbaum, director of the Laboratory of Cognitive Neurobiology
at Boston University. "The Berger enterprise is ambitious,
aiming to provide a prosthesis for memory. The need is high, because
of the prevalence of memory disorder in aging and disease associated
with loss of function in the hippocampus."
Forming new long-term memories may involve such tasks as learning
to recognize a new face, or remembering a telephone number or directions
to a new location. Success depend on the proper functioning of the
hippocampus. While this part of the brain doesn't store long-term
memories, it re-encodes short-term memory so it can be stored as
long-term memory.
It's the area that's often damaged as a result of head trauma, stroke,
epilepsy and neurodegenerative disorders such as Alzheimer's disease.
Currently, no clinically recognized treatments exist for a damaged
hippocampus and the accompanying memory disorders.
Berger's team began its research by studying the re-encoding process
performed by neurons in slices of rat hippocampi kept alive in nutrients.
By stimulating these neurons with randomly generated computer signals
and studying the output patterns, the group determined a set of
mathematical functions that transformed any given arbitrary input
pattern in the same manner that the biological neurons do. And according
to the researchers, that's the key to the whole issue.
"It's an impossible task to figure out what your grandmother
looks like and how I would encode that," said Berger. "We
all do a lot of different things, so we can't create a table of
all the things we can possibly look at and how it's encoded in the
hippocampus. What we can do is ask, 'What kind of transformation
does the hippocampus perform?'
"If you can figure out how the inputs are transformed, then
you do have a prosthesis. Then I could put that into somebody's
brain to replace it, and I don't care what they look at -- I've
replaced the damaged hippocampus with the electronic one, and it's
going to transform inputs into outputs just like the cells of the
biological hippocampus."
Dr. John J. Granacki, director of the Advanced Systems Division
at USC, has been working on translating these mathematical functions
onto a microchip. The resulting chip is meant to simulate the processing
of biological neurons in the slice of rat hippocampus: accepting
electrical impulses, processing them and then sending on the transformed
signals. The researchers say the microchip is doing exactly that,
with a stunning 95 percent accuracy rate.
"If you were looking at the output right now, you wouldn't
be able to tell the difference between the biological hippocampus
and the microchip hippocampus," Berger said. "It looks
like it's working."
The team next plans to work with live rats that are moving around
and learning, and will study monkeys later. The researchers will
investigate drugs or other means that could temporarily deactivate
the biological hippocampus, and implant the microchip on the animal's
head, with electrodes into its brain.
"We will attempt to adapt the artificial hippocampus to the
live animal and then show that the animal's performance -- dependent
in these tasks on an intact hippocampus -- will not be compromised
when the device is in place and we temporarily interrupt the normal
function of the hippocampus," said Sam A. Deadwyler, "thus
allowing the neuro-prosthetic device to take over that normal function."
Deadwyler, a professor at Wake Forest University, is working on
measuring the hippocampal neuron activity in live rats and monkeys.
The team expects it will take two to three years to develop the
mathematical models for the hippocampus of a live, active rat and
translate them onto a microchip, and seven or eight years for a
monkey. They hope to apply this approach to clinical applications
within 10 years. If everything goes well, they anticipate seeing
an artificial human hippocampus, potentially usable for a variety
of clinical disorders, in 15 years.
Overall, experts find the results promising.
"We are nowhere near applicability," said Boston University's
Eichenbaum. "But the next decade will prove whether this strategy
is truly feasible."
"There is a big gap in making the microchip work in a slice
preparation and getting it to work in a human being," added
Norbert Fortin, a neuroscientist from the Cognitive Neurobiology
Lab at Boston University. "However, their approach is very
methodical, and it is not unreasonable to think that in 15 to 20
years such a chip could help, to some degree, a patient who suffered
from hippocampal damage."
© Copyright 2004, Lycos, Inc. All Rights Reserved.
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