Paroxysmal depolarising shift

Cellular dysregulation Paroxysmal depolarising shift (PDS)

Seizures are initiated by abnormal depolarisations in a neuron or group of neurons. The paroxysmal depolarising shift is a sudden abnormal depolarisation which is characterized by a train of action potentials.

So in contrast to the normal physiological situation in which the sodium channel is inactivated during the repolarisation, now the channels are still activated generating a number of depolarisations.

1

Which of the following is NOT commonly associated with neuronal membrane instability? 

2

For an action potential to begin, an area of excitable membrane must

3

During the absolute refractory period, the membrane