Noise induced synchronization in a neuronal oscillator

Neuronal oscillators engage into quasiperiodic or phase locked discharges when driven by a weak periodic signal. These responses contrast with those evoked by weak aperiodic noise-like forcing mimicking realistic stimuli. The latter produce synchronous firing across neuronal populations, reflecting reliable firing. We analyze this phenomenon using random dynamical system theory applied to a biophysical neuronal oscillator model. We show that in agreement with experimental observations, weak noise-like forcing leads invariably to discharge synchrony of neuronal oscillators. In terms of neuronal coding, our result shows that neurons can reliably encode realistic broad-band noise-like signals, even though they may not do so for periodic signals. (C) 2003 Elsevier B.V. All rights reserved.