Cellular mechanisms of the dynamics and control of bursting activity

Georgia State University Research Foundation, Inc., Atlanta GA

Investigators

Abstract

In this proposal the PI will study the onset and control of bursting activity of neurons in the central pattern generator (CPG) that controls heart beating in the medicinal leech using neuron-computer interface (dynamic clamp and hybrid systems analysis). Neurons exhibit a variety of qualitatively different activity, such as bursting, tonic spiking, sub-threshold oscillations and rest potentials. Bursting is commonly involved in the control of rhythmic motor behaviors, it is associated with the sleep state of the brain in contrast to a vigilant state, and/or can be a distinguishing factor between pathological and normal dynamics of the central nervous system (CNS). Such medical conditions as sudden infant death syndrome, epilepsy and Parkinson's disease are examples of the medical conditions which are caused by malfunction in the dynamics of the CNS. The complexity of endogenous dynamics supporting bursting originates from the dynamical diversity of ionic currents. The PI will apply the analytical tools of the theory of dynamical systems to the analysis of stationary and oscillatory regimes of activity of living neurons to explain how bursting activity is generated and can be controlled. The dynamic clamp will be used to artificially reintroduce or augment a particular ionic current; while hybrid systems approach will be employed to create and study the interactions of two neurons, where one is the mathematical model running in real-time and the other is a living neuron. To identify physical mechanisms by which bursting can arise from other regimes and how it can be regulated, the PI proposes two goals. 1. To investigate the role of slow ionic currents in determining the characteristics of bursting activity. 2. To study the dynamics of a pair of mutually inhibitory neurons. The PI will also continue to recruit minority students to participate in research in his laboratory, and will continue to encourage them to pursue academic careers. The PI will continue to work with students in the Atlanta metro area schools to foster their interest in science. In the PIs laboratory, graduate and undergraduate students will be involved in the research projects using interdisciplinary methods from mathematics, physics and neuroscience.