Date of this Version
Journal of Neurophysiology
Coherent neural oscillations represent transient synchronization of local neuronal populations in both normal and pathological brain activity. These oscillations occur at or above gamma frequencies (>30 Hz) and often are propagated to neighboring tissue under circumstances that are both normal and abnormal, such as gamma binding or seizures. The mechanisms that generate and propagate these oscillations are poorly understood. In the present study we demonstrate, via a detailed computational model, a mechanism whereby physiological noise and coupling initiate oscillations and then recruit neighboring tissue, in a manner well described by a combination of stochastic resonance and coherence resonance. We develop a novel statistical method to quantify recruitment using several measures of network synchrony. This measurement demonstrates that oscillations spread via preexisting network connections such as interneuronal connections, recurrent synapses, and gap junctions, provided that neighboring cells also receive sufficient inputs in the form of random synaptic noise. "Epileptic" high-frequency oscillations (HFOs), produced by pathologies such as increased synaptic activity and recurrent connections, were superior at recruiting neighboring tissue. "Normal" HFOs, associated with fast firing of inhibitory cells and sparse pyramidal cell firing, tended to suppress surrounding cells and showed very limited ability to recruit. These findings point to synaptic noise and physiological coupling as important targets for understanding the generation and propagation of both normal and pathological HFOs, suggesting potential new diagnostic and therapeutic approaches to human disorders such as epilepsy.
Originally published in the Journal of Neurophysiology © 2015 American Physiological Society
This is a pre-publication version. The final version is available at http://dx.doi.org/10.1152/jn.00643.2010
epilepsy, synchrony, noise
Stacey, W. C., Krieger, A., & Litt, B. (2011). Network Recruitment to Coherent Oscillations in a Hippocampal Computer Model. Journal of Neurophysiology, 105 (4), 1464-1481. http://dx.doi.org/10.1152/jn.00643.2010
Date Posted: 25 October 2018
This document has been peer reviewed.