Cellular Neuroscience - Neuronal Function

Neuronal Function

One prominent characteristic of many neurons is excitability. Neurons generate electrical impulses or changes in voltage of two types: graded potentials and action potentials. Graded potentials occur when the membrane potential depolarizes and hyperpolarizes in a graded fashion relative to the amount of stimulus that is applied to the neuron. An action potential on the other hand is an all-or-none electrical impulse. Despite being slower than graded potentials, action potentials have the advantage of traveling long distances in axons with little or no decrement. Much of the current knowledge of action potentials comes from squid axon experiments by Sir Alan Lloyd Hodgkin and Sir Andrew Huxley.