How do actions potentials arise?

Action potentials arise when a neuron's membrane potential reaches a threshold, typically due to depolarization caused by the influx of sodium ions (Na+) through voltage-gated sodium channels. This rapid change in membrane potential leads to a positive feedback loop, where more sodium channels open, causing further depolarization. Once the peak is reached, potassium channels open, allowing potassium ions (K+) to exit the cell, leading to repolarization. The process restores the resting membrane potential, completing the action potential cycle.