Adaptation level

Adaptation level, is the level to which an sense organ has adapted and is considered the point on a sensory continuum against which changes are noted. So for example a persons hand that has adapted to very cold water will experience less cold water as warmer than they would if they had previously held their hand in hot water.

Harry Helson developed a theory about such context sensitive effects using the notion of adaptation level as anchor point against which new stimuli are judged.