Center for Neurodynamics

Sonya Bahar, Ph.D.

 

Sonya Bahar, PhD - “Photo by August Jennewein”

Associate Professor of Biophysics
Director, Center for Neurodynamics 

Department of Physics and Astronomy 
University of Missouri at St Louis
One University Boulevard
St. Louis MO 63121

Tel: 314-516-7150
Fax: 314-516-6152 
Email: bahars@umsl.edu

 

B.S. in Physics, Drexel University, 1991

M.S. in Biophysics, University of Rochester, 1993

Ph.D. in Biophysics, University of Rochester, 1997

Editor (with Prof. Rudi Podgornik) of The Journal of Biological Physics, published by Springer.

Member-at-Large for the Division of Biological Physics of the American Physical Society. Check out the latest biophysics news.

Curriculum Vitae (pdf version)

EVOLUTIONARY DYNAMICS

We are investigating the role of mutation parameters in driving speciation in evolutionary models. We have observed phase-transition-like behavior as the maximum mutation size is varied, on various types of fitness landscapes. Optimal clustering, which can be considered as an analog of speciation, occurs for an intermediate mutation parameter. Our first work on this model recently appeared in PLoS ONE. Most recently, we have found similar behavior even on a NEUTRAL landscape, in which all simulated organisms have identical fitness.

Graduate students currently working on the project are Adam Scott and Dawn King (with many thanks to alum Dr. Nathan Dees, Ph.D. 2009!)

Bahar

NEURAL SYNCHRONIZATION

Recent doctoral student Daisuke Takeshita (Ph.D. 2010, now pursuing postdoctoral research with Prof. Tim Gollisch's lab) studied the synchronization of neural activity in the rat neocortex during focal seizures. Using voltage-sensitive-dye imaging, Daisuke demonstrated a sharp rise in synchronization during seizures. This study just appeared in the journal Chaos, in a focus issue honoring Frank Moss.

synchmap

Recent doctoral student Roxana Contreras (Ph.D. 2009), studied eye-target synchronization in normal subjects and mild traumatic-brain-injured (mTBI) patients. Her most recent work in this area appeared in Brain Research in 2011.

TBI

EVOLUTION OF FORAGING STRATEGIES

Recent doctoral student Nathan Dees (Ph.D. 2009), who now works at the Genome Center at Washington University in St. Louis, studied the evolution of optimal foraging behavior in various species, ranging from Daphnia to paddlefish. He also investigated how nonlinear dynamical techniques can reveal the relationship between the fMRI-BOLD signal and EEG recordings in human subjects.

Daph

 

MORE NONLINEAR DYNAMICS IN BIOLOGICAL SYSTEMS AND JUST PLAIN NEUROSCIENCE (OLD PROJECTS FROM POSTDOCTORAL DAYS GONE BY...)

In vivo imaging of seizure activity in the rat neocortex...

....and human intraoperative brain imaging (postdoctoral work with Ted Schwartz)

Neural synchronization in the crayfish caudal photoreceptor (postdoctoral work wtih Frank Moss)

The Duke era...

Imaging hypoxic spreading depression in rat hippocampal slices.


Bistability and hysteresis in the response of periodically paced small pieces of bullfrog cardiac tissue. Phys. Rev. Lett. 82:2995-2998, 1999.

Spatiotemporal effects of bistability in coupled map models of cardiac dynamics(published in the Proceedings of the 5th Experimental Chaos Conference, Boca Raton, Florida, July 1999).

Control of fibrillation using nonlinear dynamics based methods in the in vivo sheep heart.

Bistability and Hysteresis in the Periodically Paced Sheep Heart.

 

DISSERTATION RESEARCH

Monovalent and divalent anion transport in the band 3 and AE2 proteins

with Phil Knauf, a most wonderful human being, and an inspiring thesis advisor....

 

"THE EARLY WORK"... (A/K/A notes from underground... secretly, by candlelight, listening to Automatic for the People...)

Time Delay Embeddings of IFS Attractors

Symbolic Dynamics for IFS Attractors

Apparently Chaotic Orbits Embedded in Closed Curves, written with Irene Hueter

 

cnd