#3 · Systems biology

Biophysical models link ion channel, noise and modulation to network firing dynamics

The dominant thread is conductance-based or stochastic modeling of neuronal excitability, in which ion channel composition, noise, plasticity and regulatory feedback are varied to determine network-level activity. A 200-neuron Hodgkin-Huxley network with STDP and stochastic synapses sustains sparse autonomous firing after brief stimulation, while bifurcation and timescale analysis explain bursting, regular and complex spiking in a cartwheel interneuron model with L-type Ca2+ and BK channels. A neuromodulation controller coupled to calcium homeostasis yields robust yet modulable activity in stomatogastric and dopaminergic neuron models. Two preprints extend the scope to alternative formulations: a murburn-based account of neuronal electricity covering resting potential, spikes and conduction velocity, and a proposed proton-tunneling noise source at the RyR2 activation site. What is new is treating modulation timing, noise sources and homeostatic regulation as explicit determinants of network dynamics, though the murburn and RyR2 proposals remain preprint-stage.