What does hyperpolarization refer to in a neuron?

Hyperpolarization in a neuron refers to a change in membrane potential that makes the inside of the cell more negative relative to the outside. This typically occurs when potassium channels open, allowing potassium ions to flow out of the neuron or when chloride ions enter, both contributing to a more negative internal environment. As a result, hyperpolarization increases the difference in charge across the neuron's membrane, moving the membrane potential further away from the threshold needed to trigger an action potential. This makes it less likely for the neuron to reach that threshold and generate an action potential, thus inhibiting its ability to fire. This critical process plays a vital role in regulating neuronal excitability and signaling.