Sensory threshold

In psychophysics, sensory threshold is the weakest stimulus that an organism can sense. Unless otherwise indicated, it is usually defined as the weakest stimulus that can be detected half the time, for example, as indicated by a point on a probability curve. Methods have been developed to measure thresholds in any of the senses.

Several different sensory thresholds have been defined;

• Absolute threshold: the lowest level at which a stimulus can be detected.
• Recognition threshold: the level at which a stimulus can not only be detected but also recognized.
• Differential threshold: the level at which an increase in a detected stimulus can be perceived.
• Terminal threshold: the level beyond which any increase to a stimulus no longer changes the perceived intensity.