title: Effect of heterogeneity and noise on cross frequency phase-phase and phase-amplitude coupling.
abstract: Cross-frequency coupling is hypothesized to play a functional role in neural computation. We apply phase resetting theory to two types of cross-frequency coupling that can occur when a slower oscillator periodically forces one or more oscillators: phase-phase coupling, in which the two oscillations are phase-locked, and phase-amplitude coupling, in which the amplitude of the driven oscillation is modulated. Our first result is that the shape of the phase resetting curve predicts the tightness of locking to a pulsatile forcing periodic input at any ratio of forced to intrinsic period; the tightness of the locking decreases as the ratio increases. Theoretical expressions were obtained for the probability density of the phases for a population of heterogeneous oscillators or a noisy single oscillator. Results were confirmed using two types of simulated networks and experiments on hippocampal CA1 neurons. Theoretical expressions were also obtained and confirmed for the probability density of N spike times within a single cycle of low frequency forcing. The second result is a suggested mechanism for phase-amplitude coupling in which progressive desynchronization leads to decreasing amplitude during a low frequency forcing cycle. Network simulations confirmed the theoretical viability of this mechanism, and that it generalizes to more diffuse input.
authors.affiliation: Department of Cell Biology and Anatomy .
authors.forename: Ruben
authors.initials: R
authors.lastname: Tikidji-Hamburyan
authors.forename: Eric C
authors.initials: EC
authors.lastname: Lin
authors.forename: Sonia
authors.initials: S
authors.lastname: Gasparini
authors.forename: Carmen C
authors.initials: CC
authors.lastname: Canavier
mesh_terms: D000818:Animals; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D016571:Neural Networks, Computer; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley