Reizdifferenz

Reizdifferenz refers to the smallest detectable difference between two stimuli. It is a fundamental concept in psychophysics, the study of the relationship between physical stimuli and the sensations and perceptions they produce. Also known as the just-noticeable difference (JND), it quantifies the sensitivity of our sensory systems. For example, if you are holding a weight and gradually add more weight, the reizdifferenz would be the smallest amount of additional weight you can perceive as different from the original. Similarly, in hearing, it's the smallest change in loudness or pitch that can be noticed.

The magnitude of the reizdifferenz is not absolute but depends on the intensity of the original stimulus. This relationship is described by Weber's Law, which states that the reizdifferenz is a constant proportion of the original stimulus. This means that to detect a difference, a larger change is needed when the initial stimulus is stronger. For instance, you'd need to add more weight to a heavy object to notice a difference compared to adding the same amount of weight to a very light object.

Reizdifferenz has practical implications in various fields, including product design, marketing, and sensory evaluation. Understanding how much change is needed for a difference to be perceived can help in designing products with subtle yet effective variations, or in determining the minimum change in advertising that will capture attention. It is a key measure of sensory acuity.