.. currentmodule:: brian .. index:: pair: example usage; NeuronGroup pair: example usage; Equations pair: example usage; run pair: example usage; StateMonitor .. _example-misc_current_clamp: Example: current_clamp (misc) ============================= An example of single-electrode current clamp recording with bridge compensation (using the electrophysiology library). :: from brian import * from brian.library.electrophysiology import * taum = 20 * ms # membrane time constant gl = 1. / (50 * Mohm) # leak conductance Cm = taum * gl # membrane capacitance Re = 50 * Mohm # electrode resistance Ce = 0.5 * ms / Re # electrode capacitance eqs = Equations(''' dvm/dt=(-gl*vm+i_inj)/Cm : volt Rbridge:ohm # bridge resistance I:amp # command current ''') eqs += current_clamp(i_cmd='I', Re=Re, Ce=Ce, bridge='Rbridge') setup = NeuronGroup(1, model=eqs) soma = StateMonitor(setup, 'vm', record=True) recording = StateMonitor(setup, 'v_rec', record=True) # No compensation run(50 * ms) setup.I = .5 * nA run(100 * ms) setup.I = 0 * nA run(50 * ms) # Full compensation setup.Rbridge = Re run(50 * ms) setup.I = .5 * nA run(100 * ms) setup.I = 0 * nA run(50 * ms) plot(recording.times / ms, recording[0] / mV, 'b') plot(soma.times / ms, soma[0] / mV, 'r') show()