68 Computational Neuroscience: Simulated Demyelinating Neuropathies and Neuronopathies
in the ALS1 and ALS2 cases during the long-duration depolarizing
(Fig. 20) and hyperpolarizing (Fig. 22) stimuli. However, during the
hyperpolarizing current stimuli, these currents fl ow in the opposite
direction.
In the most abnormal ALS3 case, the current kinetics shows the
initiation and generation of spontaneous action potential after the
termination of the applied long-duration hyperpolarizing current
stimuli (Fig. 21a–c). The action potential generation at the node
depends on the activation of sodium (Na
+
) and fast potassium (K
f
+
)
channels, as the slow potassium (K
s
+
) channels are blocked there
(Fig. 21a). The action potential generation, at the paranodal ...