This image shows nanotubes used in synthetic synapse and apparatus used to create them. Credit: USC Viterbi School of Engineering |
Engineering
researchers the University of Southern California have made a
significant breakthrough in the use of nanotechnologies for the
construction of a synthetic brain. They have built a carbon nanotube
synapse circuit whose behavior in tests reproduces the function of a
neuron, the building block of the brain.
The
team, which was led by Professor Alice Parker and Professor Chongwu
Zhou in the USC Viterbi School of Engineering Ming Hsieh Department of
Electrical Engineering, used an interdisciplinary approach combining
circuit design with nanotechnology to address the complex problem of
capturing brain function.
In
a paper published in the proceedings of the IEEE/NIH 2011 Life Science
Systems and Applications Workshop in April 2011, the Viterbi team
detailed how they were able to use carbon nanotubes to create a synapse.
Carbon
nanotubes are molecular carbon structures that are extremely small,
with a diameter a million times smaller than a pencil point. These
nanotubes can be used in electronic circuits, acting as metallic
conductors or semiconductors.
“This
is a necessary first step in the process,” said Parker, who began the
looking at the possibility of developing a synthetic brain in 2006. “We
wanted to answer the question: Can you build a circuit that would act
like a neuron? The next step is even more complex. How can we build
structures out of these circuits that mimic the function of the brain,
which has 100 billion neurons and 10,000 synapses per neuron?”
Parker
emphasized that the actual development of a synthetic brain, or even a
functional brain area is decades away, and she said the next hurdle for
the research centers on reproducing brain plasticity in the circuits.
The
human brain continually produces new neurons, makes new connections and
adapts throughout life, and creating this process through analog
circuits will be a monumental task, according to Parker.
She
believes the ongoing research of understanding the process of human
intelligence could have long-term implications for everything from
developing prosthetic nanotechnology that would heal traumatic brain
injuries to developing intelligent, safe cars that would protect drivers
in bold new ways.
For
Jonathan Joshi, a USC Viterbi Ph.D. student who is a co-author of the
paper, the interdisciplinary approach to the problem was key to the
initial progress. Joshi said that working with Zhou and his group of
nanotechnology researchers provided the ideal dynamic of circuit
technology and nanotechnology.
“The
interdisciplinary approach is the only approach that will lead to a
solution. We need more than one type of engineer working on this
solution,” said Joshi. “We should constantly be in search of new
technologies to solve this problem.”
