What is a receptor potential?

A receptor potential is a change in the membrane potential of a sensory receptor cell that occurs in response to a stimulus. It is a graded potential, in which the magnitude of the potential is proportional to the intensity of the stimulus.

Receptor potentials are the first step in sensory transduction, the process by which sensory information is converted into electrical signals that can be processed by the nervous system.

The receptor potential is generated by the opening and closing of ion channels, which allows ions like sodium (Na+) and potassium (K+) to flow into or out of the cell, causing a change in the membrane potential.

The duration of the receptor potential varies depending on the type of receptor and the nature of the stimulus. Some receptor potentials are short-lived and rapidly decay, while others can be sustained for several seconds or longer.

The strength of the receptor potential determines whether or not an action potential is generated in the sensory neuron and ultimately whether the stimulus is perceived by the brain.