Electrodermal activity

Galvanic skin response (GSR), also known as electrodermal response (EDR), psychogalvanic reflex (PGR), or skin conductance response (SCR), is a method of measuring the electrical resistance of the skin. There has been a long history of electrodermal activity research, most of it dealing with spontaneous fluctuations.

One branch of GSR explanation interprets GSR as an image of activity in certain parts of the body. The mapping of skin areas to internal organs is usually based on acupuncture points. ^{[citation needed]}

Description

The device measures electrical resistance between 2 points, and is essentially a type of ohmmeter. The two paths for current are along the surface of the skin and through the body. Active measuring involves sending a small amount of current through the body.

Due to the response of the skin and muscle tissue to external and internal stimuli, the resistance can vary. When correctly calibrated, the GSR can measure these subtle differences. There is a relationship between sympathetic activity and emotional arousal, although one cannot identify the specific emotion being elicited. The GSR is highly sensitive to emotions in some people. Fear, anger, startle response, orienting response and sexual feelings are all among the emotions which may produce similar GSR responses. These reactions have allowed lie detectors to have some success.

History

The scientific study of GSR began in the early 1900s. One of the first references to the use of GSR instruments in Psychoanalysis is the book by C. G. Jung entitled Studies in Word Analysis, published in 1906.^[1] Wilhelm Reich also studied GSR in his experiments at the Psychological Institute at the University of Oslo in 1935-6 to confirm the existence of a bio-electrical charge behind his concept of vegetative, pleasurable 'streamings.'^[2] GSR was used for a variety of types of research in the 1960s through the late 1970s, with a decline in use as more sophisticated techniques (such as EEG and MRI) replaced it in many areas of psychological research. GSR still sees limited use today, as it is possible to use with low-cost hardware (galvanometer).

Uses

GSR measurement is one component of polygraph devices and is used in scientific research of emotional arousal.

The E-meter, which is used by the Church of Scientology, is a GSR measurement device.

GSR measurement is also becoming commonplace in hypnotherapy and psychotherapy practice where it can be used as a method of detecting depth of hypnotic trance prior to suggestion therapy commencing. When traumatic material is experienced by the client (for example, during hypnoanalysis), immediate changes in galvanic skin response can indicate that the client is experiencing emotional arousal. It is also used in behavior therapy to measure physiological reactions such as fear.

Notes

^ The Biofeedback Monitor
^ Reich, W. 'Experimentelle Ergebnisse ueber die electrische Funktion von Sexualitat und Angst' (Sexpolverlag, Copenhagen, 1937). Translated as 'Experimental investigation of the electrical function of sexuality and anxiety' in J. of Orgonomy, Vol. 3, No. 1-2, 1969.

References

Conesa, J. (1995). Electrodermal palmar asymmetry and nostril dominance. Perceptual and Motor Skills, 80, 211-216

External links

[1] The Biofeedback Monitor

[2] Reich, W. 'Experimentelle Ergebnisse ueber die electrische Funktion von Sexualitat und Angst' (Sexpolverlag, Copenhagen, 1937). Translated as 'Experimental investigation of the electrical function of sexuality and anxiety' in J. of Orgonomy, Vol. 3, No. 1-2, 1969.

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