Ermentrout "Lab"

People

Postdocs

• Julia Arciera (CBSG)
• Stefanos Folias (CBSG)
• Cheng Ly (NSF)

Graduate students

• Stephanie Hoogendoorn
• Aushra Abouzeid
• Angela Reynolds
• Sergio Verduzco
• Sashi Marella
• Alex Urban

I also frequently work with undergraduates and I am always willing to supervise them on various projects of interest.

Current Projects

• Noisy oscillators

  How does noise interact with rhythmic phenomena in the nervous system and other areas of biology? We use small noise expansion and the phase resetting curve of oscillators to understand how correlated inputs can affect the synchrony or both coupled and uncoupled oscillators. We also characterize what types of oscillators are optimal fro transmitting correlated inputs to correlated outputs. This work is with the Urban lab as well as with students Aushra Abouzeid & Sashi Marella and postdoc Cheng Ly.

• Dynamics and phase resetting

  The phase resetting curve (PRC) tells us how the timing of inputs shift the timing of oscillators. The shapse of these curves are important both in coupled and in forced systems and play a critical role in synchronization. In neurons, there are many currents which are subject to modulation and these currents can have a strong affect on the shape and sensitivity of the PRC. Uncorrelated noise and coupling to other oscillators also alter the shape of the PRC. We use nonlinear dynamics and simulations to study how these curves are changed. This work is with postdoc TaeWook Ko, former student, Boris Gutkin, and in collaboration with several experimentalists including Nathan Urban (CMU), Charlie Wilson (UTSA), and Theoden Netoff (UM).

• Pattern formation in neural systems

  This is fun stuff. I continue a long held interest in hallucinations and phosphenes as well as various types of pattern sensitive and reflex epilepsies. I am interested in mechanisms through which flickering light can induce geometric hallucinations as well as seizures in susceptible populations. This work is with Mark Bodner and Sergio Verduzco. With George Oster and Alistair Boettiger, we have revisited early work on the pigmentation and shell construction of gastropods.

• Waves and persistent states in neural systems

  Due to the massive recurrent interactions between neurons, networks are able to sustain various types of persistent activity. By persistent, I mean activity that remains after a stimulus is removed. Working memory is believed to be such a state - a localized region of cortex remains active until the memory task is completed. We have several types of models involving combinations of multi-region interactions, multi-layer interactions and facilitation. This work is with Stephanie Hoogendoorn, Mark Bodner, and Sergio Verduzco.

  Another type of persistent activity comes in the form of propagating waves. These are observed in brain slices, cell cultures, and in vivo. We use spatial networks of neurons and singular perturbation theory to study propagation of activity in one- and two-dimensions. This work is with Jian-young Wu (Georgetown), Sashi marella, and Julie Goulet.

• Modeling the inflammatory response

  Pathogens, damage, and other insults to the body can result in inflammation which can sometimes be worse than the original insult. We work closely with several people at UPMC (Gilles Clermont, Yoram Vodovotz) developing models for the signalling pathways and responses of the innate immune system. We have applied these models to influenza, malaria, lung inflammation, necrotizing enterocolitis, and multiple organ dysfunction syndrome. This is work with David Swigon, Jon Rubin, and students, Angela Reynolds and Ian Price.