Etterhyperpolarisering
Etterhyperpolarisering, or etterhyperpolarisering in Norwegian, is the transient hyperpolarization of a neuron’s membrane potential that follows an action potential. After the spike, the membrane potential briefly becomes more negative than the resting level, typically due to potassium efflux and other currents that outlast the repolarization phase. This event reduces the likelihood of immediate subsequent firing and helps shape the neuron's response to input.
There are three main components of afterhyperpolarization: fast AHP (fAHP), medium AHP (mAHP), and slow AHP (sAHP).
Mechanistically, the fAHP is largely due to activation of voltage-gated and calcium-activated potassium channels that rapidly
Functionally, AHP shapes neuronal excitability by modulating inter-spike intervals and firing patterns. It contributes to spike-frequency