Figure 4

Simulation of alcohol action upon the 2 compartment Purkinje neuron model. A, Membrane potential at the soma. The red arrow, labelled “Alcohol”, symbolises the introduction of alcohol to the model Purkinje cell. A progressing alcohol block of Na⁺/K⁺ pumps is symbolised by the negatively orientated red arrow, labelled “Sodium-Potassium Pump Activity”. As the Na⁺/K⁺ pump activity decreases, the model progresses through a number of labelled activity states: Quiescent, Bimodal, Tonic and Depolarisation Block. Note in the Bimodal phase, the second quiescent period is shorter than the first. B, Membrane potential at the dendrite. Note that during the Depolarisation Block phase at the soma, the dendrites are not in depolarisation block and continue to fire. These dendritic spikes travel to the soma and “furrow” its depolarisation block quiescence with small perturbations in membrane potential.