Psychophysics is basically an interdisciplinary branch of psychology and physics; it studies the relationship between physical stimuli and the sensations along with the perceptions they produce.
The psychophysicists analyze the perceptual processes by studying the effect on a behavior; further, they also study the systematically varying properties of a stimulus along one or more physical dimensions.
The concept of psychophysics was first time used in 1860 by Gustav Theodor Fechner in Leipzig, Germany.
Fechner published his research namely ‘Elemente der Psychophysik’ (i.e. Elements of Psychophysics).
Following are the commonly used terms in psychophysics −
Signal detection theory − It explains the interaction of the sensory capabilities and the decision making elements in detecting the stimulus.
‘Ideal observer analysis − It is a technique for investigating i.e. how information has processed in a perceptual system.
Difference thresholds − It helps to differentiate two stimuli. This point is termed just-noticeable difference.
Absolute threshold − The point at which the person first detects the stimulus strength i.e. presence of stimulus.
Scaling − It uses rating scales to allocate relative values.
Modern Psychophysicists research on −
Vision
Hearing
Touch (or sense)
Based on these, psychophysicists measure what the perceiver's decision extracts from the stimulus.
In the present world, psychophysics is commonly applied to treat many of psychological problems.