Just-noticeable difference
Amount a stimulus must be changed to be detected / From Wikipedia, the free encyclopedia
In the branch of experimental psychology focused on sense, sensation, and perception, which is called psychophysics, a just-noticeable difference or JND is the amount something must be changed in order for a difference to be noticeable, detectable at least half the time.[1] This limen is also known as the difference limen, difference threshold, or least perceptible difference.[2]