Noise, Waves and Synchrony

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

Ongoing activity in the nervous system and how it impacts sensory and other inputs is the subject of much recent experimental activity. In particular, it is clear that the intrinsic interactions between neuronal circuits in absence of inputs can have a strong impact on how the system responds to incoming stimuli even at the large scale cognitive level. Thus, nonlinear dynamics methods will be applied to problems in theoretical neuroscience dealing with this question. Specifically, the research group will study the propagation of spontaneous and evoked waves in neuronal networks as well as the conditions for synchronization in these systems. The effects of both pulsatile and frozen noise inputs on oscillatory networks of neurons will also be studied. A particular question of interest is how input correlations interact with intrinsic activity to shape the output correlations. Finally, the group will study how different ionic currents and modulators shape the ability of neurons to synchronize their behavior and how they respond to external inputs. How humans perceive the world is governed both by the sensory inputs with which they are constantly bombarded and by their previous experience. This experience, as well as the natural wiring of the nervous system, shapes the spontaneous behavior of our brains and this spontaneous activity strongly modulates the sensory inputs. In this project, computational and mathematical models of neurons are used to understand what kinds of spontaneous behavior are possible, how this depends on the wiring and how this activity interacts with sensory inputs. For example, if many neurons fire together synchronously as a consequence of both common inputs and their intrinsic interactions, this could provide a strong signal for the importance of the sensory stimulus. These studies can help guide experiments which together with models and theory lead to a better understanding of normal brain function.