Oscillatory networks often include neurons that membrane potential resonance, a peak in the voltage amplitude as a function of current input at a nonzero (resonance) frequency (fres). Although fres has been correlated to the network frequency (fnet) in a variety of systems, a causal relationship between the two has not been established. We examine the hypothesis that combinations of biophysical parameters that shift fres, without changing other attributes of the impedance profile, also shift fnet in the same direction. We test this hypothesis, computationally and experimentally, in an electrically coupled network consisting of intrinsically oscillatory (O) and resonator (R) neurons. Using a two-cell model of such a network, we show increasing fres of R directly increases fnet and that this effect becomes more prominent if the amplitude of resonance is increased. Notably, the effect of fres on fnet is independent of the parameters that define the oscillator, or the combination of parameters in R that produce the shift in fres, so long as this combination produces the same impedance vs. frequency relationship. We experimentally verify the model predictions, using the dynamic clamp technique, by connecting a model resonator to the pacemaker PD neurons of the crab Cancer borealis pyloric network, using electrical synapses, and show that the pyloric network frequency can be shifted by changing fres in the resonator. Our results provide compelling evidence that resonance frequency and amplitude strongly influence the network oscillation frequency and therefore modulators may target these attributes in order to modify rhythmic activity.
- computational model
- dynamic clamp
- Copyright © 2016, Journal of Neurophysiology