in collaboration with
Ronald L. Calabrese
Department of Biology
Emory University
and
Stephen P. DeWeerth
School of Electrical and Computer Engineering
Georgia Institute of Technology
A post-doctoral position is available immediately as a part of a
collaborative NSF-sponsored project (see attached summary) to develop
analog VLSI circuit models of intersegmental coordination in
biological motor systems. The person filling this position will act
as a bridge between the two laboratories (less than 15 minutes apart
by car) with primary responsibilities to acquire the necessary
biological knowledge at Emory and to utilize this knowledge in the
development of aVLSI models at Georgia Tech. The post-doc will gain
knowledge of the utility of aVLSI technology in biological research,
will make sure that all the silicon models are firmly based in
biology, and will motivate the studies performed on the resulting
models.
Applicants should have a good background in neuroscience and strong
quantitative skills. Preference will be given to applicants with a
background in system-level modeling (either physiological or
mathematical), especially in intersegmental motor systems. The
position is available for two to three years.
Applications including a statement of research interest, a CV, and the
names/addresses of at least three references should be sent via e-mail
to both investigators at:
steve.deweerth@ece.gatech.edu
rcalabre@biology.emory.edu
or alternatively to:
Prof. Stephen P. DeWeerth
School of Electrical and Computer Engineering
Georgia Institute of Technology
Atlanta, GA 30332-0250
Additional information about the labs can be acquired from the following
World-Wide Web locations:
http://calabreselx.biology.emory.edu/welcome.html
http://www.ece.gatech.edu/research/labs/ccss/
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Project Summary
Analog-VLSI Modeling of Intersegmental Coordination
It is the aim of this project to bring together biologists and engineers
to develop new techniques and architectures for exploring the mechanisms
that underlie motor behaviors in neural systems. In particular, efforts
will be focused on developing a better understanding of intersegmental
coordination in motor pattern-generating networks that mediate axial
locomotion in invertebrates and vertebrates. These networks represent a
tractable level of complexity and much is known about their structure
(synaptic connectivity and membrane properties of the component neurons)
and function. These motor patterns are produced by segmental neural
oscillators that are coordinated to produce a wave of a motor activity
along the animal's axis. A primary goal of the investigations will be to
understand how this intersegmental coordination is accomplished and how
it depends on the intersegmental connectivity and the structure and
excitability of the segmental oscillators.
To accomplish this goal, analog very large-scale integrated (aVLSI)
circuit models of segmental oscillators with a flexible communication
protocol for intersegmental communication will be developed. The
starting point of the research will be the wealth of experimental data
available about the membrane and synaptic properties of interneurons
that compose the segmental oscillators in the leech heartbeat system.
This data will facilitate the production of realistic aVLSI model
neurons and synapses. These model neurons will be used to construct
segmental oscillator models based on available connectivity diagrams and
neuronal membrane properties of segmental oscillators involved in leech
and lamprey swimming. These models will be used to study the general
principles that underlie intersegmental coordination in these systems.
The segmental oscillators will be interconnected in various patterns,
beginning with those suggested by the available physiological data. The
effects of intersegmental connectivity and segmental oscillator
structure will be evaluated.
It is expected that this project will contribute to its underlying
biological and engineering disciplines in the following ways: (i) it
will shed light on the biological mechanisms mediating intersegmental
coordination of neuronal oscillators involved in motor pattern
formation; (ii) it will result in the development of aVLSI tools that
will be of general applicability in the study of large-scale neuronal
networks; and (iii) the resulting models of axial locomotor pattern
generators will serve as a starting point for the construction of
artificial systems capable of axial locomotion and other complex motor
behaviors.
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