- —psychophysical /suy'koh fiz"i keuhl/, psychophysic, adj. —psychophysically, adv. —psychophysicist /suy'koh fiz"euh sist/, n./suy'koh fiz"iks/, n. (used with a sing. v.)the branch of psychology that deals with the relationships between physical stimuli and resulting sensations and mental states.[1875-80; < G Psychophysik. See PSYCHO-, PHYSICS]
* * *Branch of psychology concerned with the effect of physical stimuli (such as sound waves) on mental processes.Psychophysics was established by Gustav Theodor Fechner in the mid-19th century, and since then its central inquiry has remained the quantitative relation between stimulus and sensation. A key tenet has been Weber's law. Psychophysical methods are used today in vision research and audiology, psychological testing, and commercial product comparisons (e.g., tobacco, perfume, and liquor).
* * *study of quantitative relations between psychological events and physical events or, more specifically, between sensations and the stimuli that produce them.Physical science permits, at least for some of the senses, accurate measurement on a physical scale of the magnitude of a stimulus. By determining the stimulus magnitude that is just sufficient to produce a sensation (or a response), it is possible to specify the minimum perceptible stimulus, or the absolute stimulus threshold (stimulus limen), for the various senses. The central inquiry of psychophysics pertains to the search for a lawful, quantitative relation between stimulus and sensation for the range of stimuli between these limits.Psychophysics was established by German scientist and philosopher Gustav Theodor Fechner (Fechner, Gustav Theodor). He coined the word, developed the fundamental methods, conducted elaborate psychophysical experiments, and began a line of investigation that still persists in experimental psychology. Fechner's classic book Elemente der Psychophysik (1860) may be looked upon as the beginning not only of psychophysics but also of experimental psychology.Trained in physics, Fechner in his later life became interested in metaphysics and searched for a way of relating the spiritual to the physical world. He hit upon the notion of measuring sensation in relation to its stimulus. German physiologist Ernst Heinrich Weber (Weber, Ernst Heinrich) had discovered that the amount of change in magnitude of a given stimulus necessary to produce a just-noticeable change in sensation always bore an approximately constant ratio to the total stimulus magnitude. This fact, properly speaking, is Weber's law: if two weights differ by a just-noticeable amount when separated by a given increment, then, when the weights are increased, the increment must be proportionally increased for the difference to remain noticeable. Fechner applied Weber's law to the measurement of sensation in relation to a stimulus. The resulting formula Fechner named Weber's law (often called the Fechner-Weber law). It expresses the simple relation that the magnitude of a stimulus must be increased geometrically if the magnitude of sensation is to increase arithmetically. For physiologists and for many philosophers, this allowed the measurement of sensation in relation to a measured stimulus and thereby created the possibility of a scientific quantitative psychology.More recently, psychophysicists have suggested that psychic magnitudes be assessed by direct scaling experiments rather than by deriving a sensation scale based on discrimination judgments.Psychophysical methods are used today in studies of sensation and in practical areas such as product comparisons and evaluations (e.g., tobacco, perfume, and liquor) and in psychological and personnel testing.
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Psychophysics — is a subdiscipline of psychology dealing with the relationship between physical stimuli and their subjective correlates, or percepts. Psychophysics has been described variously as “the scientific study of the relation between stimulus and… … Wikipedia
Psychophysics — Psy cho*phys ics, n. [Psycho + physics.] The science of the connection between nerve action and consciousness; the science which treats of the relations of the psychical and physical in their conjoint operation in man; the doctrine of the… … The Collaborative International Dictionary of English
psychophysics — [sī΄kō fiz′iks] n. [ PSYCHO + PHYSICS] the branch of psychology dealing with the functional relations between the mind and physical phenomena psychophysicist n … English World dictionary
psychophysics — noun plural but singular in construction Etymology: International Scientific Vocabulary Date: 1878 a branch of psychology concerned with the effect of physical processes (as intensity of stimulation) on the mental processes of an organism •… … New Collegiate Dictionary
psychophysics — noun The branch of psychology concerned with the effects of physical stimuli on mental processes See Also: psychophysical … Wiktionary
psychophysics — The science of the relation between the physical attributes of a stimulus and the measured, quantitative attributes of the mental perception of that stimulus ( e.g., the relationship between changes in decibel level and the corresponding changes… … Medical dictionary
psychophysics — study of link between mental and physical processes Sciences and Studies … Phrontistery dictionary
psychophysics — n. study of the relationship between physical stimuli and the manner in which they are perceived in the mind (Psychology) … English contemporary dictionary
psychophysics — plural noun [treated as sing.] the branch of psychology concerned with the relations between physical stimuli and mental phenomena. Derivatives psychophysical adjective … English new terms dictionary
psychophysics — psy·cho·physics … English syllables