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Related to psychophysical: Psychophysical methods


The study of mental processes by physical methods.
The study of the relations of stimuli to the sensations they produce.



a psychological discipline that studies the quantitative relations between the physical characteristics of a stimulus and the intensity of the sensation evoked by the stimulus.

Psychophysics deals with two main groups of problems: measurement of the stimulus threshold, that is, the sensitivity limit of the human sensory system, and the construction of psychophysical scales. The first group of problems arose as a result of measurements of the intensity of sensation made in the 19th century by the German scientists W. E. Weber and G. Fechner; these measurements involved indirect scaling, in which the intensity of sensation is a mathematical function of the magnitude of the stimulus. The threshold was regarded as the point in a series of stimuli of increasing intensity that divides the series into two parts, one that causes sensation and one that does not. Modern psychophysics—or rather its applied branch, the theory of detecting signals against a background of noise—regards the threshold as a “threshold zone,” within which the probability of a response varies between 0 and 1. Dynamic sensitivity theories deny that a sensory threshold exists as an independent reality.

The second group of problems arose in connection with the use by the American scientist S. Stevens of direct scaling. In direct scaling, the magnitude of sensation—a point on the sensory scale—is determined by the subject’s own indication of the distance or relation between the intensities of stimuli in arbitrary units. Research on both groups of problems is concerned with the main theoretical problem of psychophysics, namely, the structure and metrics of the psychophysical stimulus space of sensations, which is understood as a multivector, noneuclidean space.


Kravkov, S. V. Ocherk obshchei psikhofiziologii organov chuvstv. Moscow-Leningrad, 1946.
Eksperimental’naia psikhologiia, fascs. 1–2. Edited by P. Fraisse and J. Piaget. Moscow, 1966. (Translated from French.)
Problemy psikhofiziki: Sb. Moscow, 1974.
Fechner, G. T. Elemente der Psychophysik, 3rd ed., vols. 1–2. Leipzig, 1907.
Guilford, J. P. Psychometric Methods, 2nd ed. New York, 1954.


References in periodicals archive ?
Psychophysical scaling with applications in physical work and the perception of exertion.
When certain sorts of causal connections obtain among psychophysical elements, it is conventionally true that the elements in that series constitute a person.
Why simple fractional exponents describe psychophysical events is not known but was discussed by Stevens, who observed (1970), "In sense modalities like vision and hearing, which must cope with enormous ranges of energy--sometimes exceeding [10.
Comparison of the data obtained with athletes' performance results demonstrated that for athletes having high psychophysical potential, BEO-grams have distinctive features that may be described with a set of quantitative parameters.
134) In so doing, they were manifesting both their culture's expectations and their own psychophysical endowments.
Hence, a total of 10 emotions and 10 physiological symptoms could be selected and classified into four psychophysical categories: Facilitating-positive, facilitating-negative, inhibiting-negative, and inhibiting-positive.
Table 3 Structure of the coding scheme First level Second level Third level Example Health- Psychophysical General Condition vital, fit, related Functioning good hearing self Cognitive Function being alert, having good memory Mobility disabled, climbing stairs Strength being strong, loosing strength Health Being Healthy health, feeling healthy Being Ill feeling ill Health Behavior take care of health, meditation Care Autonomy staying independent Support being cared for by children Death -- death, dying Other First Level codes are Psychological Self, Activities, Social Relations, Financial and material conditions, Society, Life in general
It was demonstrated in a previous study [7] that a relationship exists between the psychophysical perception of hardness - and, by extension, of pole climbability - and gaff penetration and gaff impact data measured during the insertion of the linemen's gaff into the wood.
Point 2 holds, of course, also for the psychological and physiological part of the psychophysical system (Point 3).
While there had been attempts prior to Fechner's (1860) to establish a quantitative psychology, most notably Herbart's (1816), these attempts failed where Fechner's succeeded because (1) at the theoretical level, he linked his quantitative psychology to quantitative physics, via his psychophysical law; (2) at the practical level, he supplemented his law with a range of alleged measurement methods; and (3) at the level of rhetoric, he persuaded others that these methods were measurement in exactly the same sense as this term is used in physics.
According to Vickers, the FAST overcomes some of the limitations of the inspection time (IT) task, a psychophysical measure that has moderate correlations with IQ scores.
In this and the next section I will discuss Kim's overall position on psychophysical relations, on mental causation, and related matters - the position he has developed and advocated over many years.