Kwabena
A. Boahen, Ph.D.
Asst Professor,
Depts of Bioengineering
and Electrical Engineering
School of Engineering and Applied Science
120 Hayden Hall/6392
(215) 573-4072 FAX: (215) 573-2071
email: kwabena@neuroengineering.upenn.edu
More information
about Dr. Boahen
Click here for selected publications since Dr. Boahen's arrival at Penn
RESEARCH INTERESTS
Very large-scale models of entire neural systems consisting of thousands
of silicon neurons that respond in real-time.
RESEARCH TECHNIQUES
Very large-scale models of entire neural systems consisting of thousands
of silicon neurons that respond in real-time.
RESEARCH SUMMARY
How come the brain uses a million times less energy per operation than computers
do? No one knows for sure. Is it because the brain is analog whereas computers
are digital? Not quite: The brain uses digital axonal spikes as well as
analog dendritic potentials.
My research suggests that it is because the brain is 'programmable' at
the level of individual connections-it learns by growing. By morphing
such customized neural circuits into a silicon chip, my lab developed
a silicon retina that computes a thousand times more energy-efficiently
than a computer does. Although this chip achieves desktop-computer performance
while consuming palmtop-computer power, it is still three orders of magnitude
shy of the retina's energy-efficiency. But this gap is closing with the
rapid miniaturization of silicon technology, which will soon enable us
to put a billion transistors on a single microchip.
A billion-transistor chip presents a daunting 'programming' task similar
to that nervous systems had to solve. It takes ten quadrillion (1016)
bits to specify how a quadrillion (1015) synapses connect the brain's
one trillion (1012) neurons-but the entire genome contains only billion
(109) bits. Having exhausted all information available in the genetic
code, neural circuits customize themselves further through interaction
with their internal and external environments. By mimicking such epigenetic
development, we are building a 'computer' that programs itself at the
level of individual connections. In particular, my lab is currently morphing
the retinotectal, geniculocortical, and hippocampal systems into silicon
by mimicking activity-dependent, neurotrophin-guided, anatomical plasticity,
as well as the biophysical differentiations of various neuronal types.
KEY WORDS:
Neuroengineering; Neuromorphic; retinomorphic; computational neuroscience; neural computation; spike coding; neural networks; vision; audition
|