Physical approach to control ion channel in a neuron

Blockers and activators can modify the conductance of the ion channels, and the channel currents are changed to regulate the membrane potential of a neuron for presenting different firing patterns. From dynamical aspect, blocking the ion channel and external stimuli are processed by adding equivalent trans-membrane current on the neuron models, however, the physical processing is not clarified. In this article, a control branch shunts channel current from the inductive channel of the FitzHugh-Nagumo (FHN) neural circuit, and external stimuli can be encoded in the ion channel rather than imposing direct forcing currents on the membrane potential. The neural circuit is controlled by shunting current from the inductor of the branch circuit in the FHN neural circuit, a constant voltage connected with a memristor is used to generate forcing current within finite frequency band rather than sole frequency, which is consistent with realistic external stimuli. The control branch circuit composes a capacitor for filtering the external stimulus and the filtered current will interact with the shunted channel current under energy exchange, as a result, changes of the energy ratio between magnetic field and electric field will modify the capacitor voltage, which corresponds to the membrane potential of the neuron model. Energy function is provided to discern the correlation between firing modes and energy level, and then coherence resonance is induced under noisy disturbance. Our results provide new insights into control of ion channels from physical aspect, that is, external energy injection via the control branch circuit (external sub-branch circuit) into the neural circuit tends to build a hybrid ion channel for regulating the energy level of the neurons. As a result, the ion channel becomes controllable following the injection of energy flow and the channel conductance becomes controllable. Therefore, the external energy is encoded in the ion channel for further adjustment in the energy level of the neuron, and then the energy levels control the neural activities.