Research The research done in our laboratory focuses on understanding the dynamical underpinnings of neural activity that is underlying brain cognitive function as well as its pathologies. That is, we would like to understand generic principles of the formation of spatiotemporal patterns in coupled dynamical systems that would mediate neuronal communication and facilitate formation of different cognitive and/or pathological states in the brain.

Image © 2005, Paul De Koninck. From www.greenspine.ca.

The specific questions include: in what types of dynamical regimes brain dynamics falls in? What types of dynamical interactions on a microscopic level (individual neurons) and well as macroscopic one (local networks) define its function? How does network topology influences its dynamical function? How we can successfully monitor changing temporal interdependencies between individual neurons and/or neural populations and understand their role during learning, recognition/recall, or in pathological states?

To answer those questions we use computational and experimental approaches. As a part of the computational approach we:

•  develop new measures that are tailored to be able to monitor causal relationships between activity of individual neurons (or oscillators) or neuronal populations.

•  investigate the temporal pattern formation in a system of non-identical non-linear oscillators in the networks having different structures.

•  investigate network reorganization based on temporal pattern formed by its elements

•  investigate formation of spatiotemporal patterning in different brain modalities during cognitive functions (learning and memory formation) as well as during pathological activity (epilepsy).

•  Model experimentally (see below) observed spatiotemporal pattern formation in the olfactory bulb.

 

In our experiments we employ optical imaging and multi-electrode recordings to investigate spatiotemporal pattern formation in the olfactory bulb and, separately in primary neuronal cultures. Optical imaging provides a means to conduct multisite recording of optically measurable quantities that are linked (directly or indirectly) to neuronal activity. Those include voltage sensitive dyes that report changes in membrane voltage of neurons and calcium dyes that report changes in calcium concentration inside the cells. Here, we are specifically interested in understanding:

 

Olfactory experiments:

•  What are the spatial and temporal characteristics of the olfactory code?

•  What physiological mechanisms underlie its formation and what is its specific functional role?

Culture experiments:

•  What dynamical regimes are observed during neuronal communications under generic conditions?

•  How modifications of network structure influence the spatiotemporal pattern formation in the network?