Periodic forcing of a model sensory neuron

Area of Science:

• Neuroscience
• Computational Neuroscience
• Biophysics

Background:

• Sensory neurons in weakly electric fish (Apteronotus leptorhynchus) exhibit complex firing behaviors, including quiescence, periodic firing, and bursting.
• The transition to bursting is characterized by a saddle-node bifurcation of periodic orbits, exhibiting type-I burst excitability.

Purpose of the Study:

• To investigate the effects of sinusoidal current modulation on the firing patterns of a model sensory neuron.
• To explore the potential for switching between periodic and burst firing modes using modulated currents.
• To examine stochastic resonance phenomena in bursting neurons with periodic inputs.

Main Methods:

• Numerical simulations of a model sensory neuron from Apteronotus leptorhynchus.
• Analysis of firing patterns under varying sinusoidal current modulation frequencies and amplitudes.
• Mapping of resonance tongues in parameter space.
• Investigation of stochastic resonance near the periodic-bursting transition.

Main Results:

• Sinusoidal modulation of injected current can induce transitions between periodic and burst firing modes.
• The switching behavior is dependent on modulation frequency and proximity to the burst excitability threshold.
• Resonance tongues in parameter space explain the observed transitions.
• Stochastic resonance can occur near the periodic-bursting transition, with bursts acting as the output events.

Conclusions:

• Modulating injected current offers a mechanism to control firing modes in sensory neurons.
• These findings have implications for electrosensory processing in electric fish and understanding other bursting neurons.
• The study highlights the role of burst excitability in phenomena like stochastic resonance, with bursts as novel output events.