Noisy inputs and the induction of on-off switching behavior in a neuronal pacemaker

UMMS Affiliation

Department of Neurology; Department of Physiology

Publication Date


Document Type



Algorithms; Animals; Axons; Biological Clocks; Data Interpretation, Statistical; Decapodiformes; Electric Stimulation; Electrophysiology; Membrane Potentials; Models, Statistical; Neurons; Stochastic Processes


Life Sciences | Medicine and Health Sciences


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.

DOI of Published Version



J Neurophysiol. 2006 Dec;96(6):3338-48. Epub 2006 Sep 6. Link to article on publisher's site

Journal/Book/Conference Title

Journal of neurophysiology

Related Resources

Link to Article in PubMed

PubMed ID