Susana Contreras: Effects of ionic concentration dynamics on neuronal activity

BCCN Berlin / GRK 1589 / Humboldt-Universität zu Berlin

Abstract

Neurons are crucial in the information transfer of the central nervous system. Their activity underlies signal processing and higher cognitive processes. Neurons are embedded in the extracellular space, which contains multiple particles, including ions. Ionic concentrations are not static. Intense neuronal activity can alter the intracellular and extracellular ionic concentrations. In this thesis, I study the interplay between neuronal activity and ionic concentration dynamics. I focus specically on the extracellular potassium and intracellular sodium concentrations. Using dynamical systems theory, I illustrate how moderate changes in these ionic concentrations can qualitatively change neuronal activity, potentially altering signal processing. I then model a conductance-based spiking neural network. The model predicts that a moderate change in the concentrations surrounding a microcircuit of neurons could modify the power spectral density of the population activity. Altogether, this work highlights the relevance of considering ionic concentration dynamics to understand neuronal activity on long time scales and provides technical insights on how to model and analyze the interplay between them.

 

Additional Information

PhD defense in the research training group GRK 1589, 'Sensory Computation in Neural Systems'.

Organized by

Prof. Dr. Susanne Schreiber & Prof. Dr. Richard Kempter