DC Propagation block

This example provides an example of action potential propagation block using a DC stimulation. This is perfectly working in silico, but can be unsafe in vivo as long DC values are unbalanced and can damage tissues surrounding the electrode

import nrv
import numpy as np
import matplotlib.pyplot as plt


model = 'MRG'
diam = 10
y = 0
z = 0
n_node = 50


t_sim = 50
t_position=0.05
t_start=20
t_duration=1
t_amplitude=1

b_start = 3
b_duration = t_sim
block_amp = 100
nseg = 3
material = nrv.load_material('endoneurium_bhadra')


L=nrv.get_length_from_nodes(diam,n_node)

axon = nrv.myelinated(y,z,diam,L,rec='nodes',dt=0.005,Nseg_per_sec=nseg,model=model)

y_elec = 100
z_elec = 0
x_elec = axon.x_nodes[np.int32(n_node/2)]   # electrode y position, in [um]
E1 = nrv.point_source_electrode(x_elec,y_elec,z_elec)

# insert test spike
axon.insert_I_Clamp(t_position, t_start, t_duration, t_amplitude)
# extra-cellular stimulation
stim_1 = nrv.stimulus()
stim_1.biphasic_pulse(b_start, block_amp, b_duration, 0, 0,anod_first=False)

stim_extra = nrv.stimulation(material)
stim_extra.add_electrode(E1,stim_1)
axon.attach_extracellular_stimulation(stim_extra)

# simulate axon activity
results = axon.simulate(t_sim=t_sim)#,footprints = footprints)
results.rasterize()

fig, axs = plt.subplots(2)
results.plot_x_t(axs[0],'V_mem')
axs[0].set_ylabel("Axon x-axis (µm)")
axs[0].set_xlabel("Time (ms)")
axs[0].set_xlim(0,30)
axs[0].set_ylim(0,np.max(results.x_rec))

results.raster_plot(axs[1],'V_mem')
axs[1].set_ylabel("Axon x-axis (µm)")
axs[1].set_xlabel("Time (ms)")
axs[1].set_xlim(0,30)
axs[1].set_ylim(0,np.max(results.x_rec))

fig.tight_layout()
#plt.show()