Noisy Inputs and the Induction of On–Off Switching Behavior in a Neuronal Pacemaker

Abstract

Neuronal oscillators can function as bistable toggle switches, flipping between quiescence and rhythmic firing in response to an input stimulus. In theory, such switching should be sensitive to small noisy inputs if the bistable states are in close proximity, which we test here using a perfused squid axon preparation. We find that small noisy stimulus currents induce a multitude of paths between two nearby stable states: repetitive firing and quiescence. The pattern of on-off switching of the pacemaker depends on the intensity, spectral properties, and phase angle of stimulus current fluctuations. Analysis by spike-triggered averaging of the stimulus currents near the transitions reveals that sinusoidal stimuli timed antiphase or in phase with repetitive firing correlates with switching of the pacemaker off or on, respectively. Our results reveal a distinct form of bistability in which noise can either silence pacemaker activity, trigger repetitive firing, or induce sporadic burst patterns similar to those recorded in a variety of normal and pathological neurons.

Inhibition of rhythmic spiking by colored noise in neural systems

“…Such phenomenon is the so-called inverse stochastic resonance (ISR), because the behavior in this phenomenon likes the reverse of that in stochastic resonance ). More importantly, a similar inhibition effect of noise has also been observed in several real biological neural systems (Paydarfar et al 2006), which implies that this type of inhibition effect might have some physiological significance. However, so far the relevant studies mainly studied the case of Gaussian white noise.…”

Coherent neural oscillations induced by weak synaptic noise

“…(47), one can see that the period of the limit cycle created by noise has a non-trivial dependence on σ and ε through its dependence on the points w ± , themselves connected to σ and ε as in Eqs. (45) or (46). Thus, the period of the limit cycle can be controlled by σ for a fixed ε without significantly affecting its coherence, provided Eq.…”

“…Noise can, however, also have the opposite effect and turn-off repetitive neuronal activity, as was discovered both experimentally [46] and theoretically [47]. In fact, Gutkin et al [47][48][49] used neural model equations with a mean input current consisting of both a constant deterministic and a random input component, to computationally confirm the inhibitory and modulation effects of noise on the neuron's spiking activity.…”

Bistability of bursting and silence regimes in a model of a leech heart interneuron

“…These two components -first, having a neuron which is identified so that a researcher can always find it from preparation to preparation; and, second, having a biophysically accurate model which describes the dynamics of these regimes -make it no surprise that it is the number one system where the bistability of tonic spiking and silence is studied with an exemplary thoroughness. These studies have made the coexistence of tonic spiking and silence into probably the most extensively studied type of bistability [6,[16][17][18][19]. In a striking contrast, there is a gap in our knowledge when it comes to understanding the mechanisms supporting the bistability of bursting and silence in the dynamics of a single neuron.…”