Psychophysics

Psychophysics studies how physical properties of stimuli relate to the sensations and perceptions they produce. It uses behavioral measurements to quantify sensory experience.

Weber–Fechner law: A family of relations describing how perceived intensity changes with physical stimulus intensity. It links changes in stimulus magnitude to changes in perceived magnitude.
Absolute threshold: The minimum stimulus intensity detectable at a specified probability under defined conditions. It operationalizes the boundary between detectable and undetectable stimulation.
Ernst Heinrich Weber: A German physiologist whose experiments on touch and weight discrimination helped establish quantitative sensory research. His discrimination findings motivated a foundational relation between stimulus change and sensation.
Visual acuity: The ability to resolve fine spatial detail, commonly measured with standardized visual targets. Threshold procedures quantify the smallest visual details that can be resolved.
Psychophysics and psychometrics: The theory and practice of measuring psychological attributes such as ability, personality, and attitudes. Psychometrics measures psychological traits, while psychophysics anchors judgments to controlled physical stimuli.
Just-noticeable difference: The smallest change in a stimulus that can be detected reliably under specified conditions. It is a basic threshold measure used to quantify sensory discrimination.
Difference threshold: The smallest detectable difference between two stimuli under specified conditions. It measures sensitivity to changes rather than to a stimulus's presence.
Gustav Fechner: A German physicist and philosopher who founded psychophysics as a systematic science of sensation. His 1860 work formalized methods and laws for connecting physical and mental quantities.
Audiometry: The measurement of hearing sensitivity using controlled sound stimuli. It applies threshold measurement to sound across frequencies.
Introspection: The examination and reporting of one's own conscious thoughts or experiences. Psychophysics tests reports against controlled stimuli rather than relying on reflection alone.

Linked from 25 pages