Threshold potential

Threshold potential refers to the critical level of membrane potential that must be reached for an action potential to be initiated in neurons and muscle cells. When a neuron is at rest, its membrane potential is typically around -70 mV to -90 mV. To generate an action potential, the membrane potential needs to depolarize to a certain level, known as the threshold potential, which is usually around -55 mV to -50 mV.