Editing Biofeedback (section)

===Electrodermograph===
An electrodermograph (EDG) measures skin electrical activity directly (skin conductance and skin potential) and indirectly (skin resistance) using electrodes placed over the digits or hand and wrist. Orienting responses to unexpected stimuli, arousal and worry, and cognitive activity can increase [[eccrine]] sweat gland activity, increasing the conductivity of the skin for electric current.<ref name="Andreassi, J. L. 2007"/>
 
In ''skin conductance'', an electrodermograph imposes an imperceptible current across the skin and measures how easily it travels through the skin. When anxiety raises the level of sweat in a sweat duct, conductance increases. Skin conductance is measured in microsiemens (millionths of a [[siemens (unit)|siemens]]). In ''skin potential'', a therapist places an active electrode over an active site (e.g., the palmar surface of the hand) and a reference electrode over a relatively inactive site (e.g., forearm). Skin potential is the voltage that develops between eccrine sweat glands and internal tissues and is measured in millivolts (thousandths of a volt). In ''skin resistance'', also called [[galvanic skin response]] (GSR), an electrodermograph imposes a current across the skin and measures the amount of opposition it encounters. Skin resistance is measured in kΩ (thousands of ohms).<ref>{{cite book | vauthors = Dawson ME, Schell AM, Filion DL | date = 2007 | chapter = The electrodermal system. | veditors = Cacioppo JT, Tassinary LG, Berntson GG | title = Handbook of psychophysiology | edition = 3rd | location = New York | publisher = Cambridge University Press }}</ref>

Biofeedback therapists use electrodermal biofeedback when treating [[anxiety disorders]], [[hyperhidrosis]] (excessive sweating), and stress.<ref name = Yucha2008/><ref>{{cite book | vauthors = Moss D | date = 2003 | chapter = The anxiety disorders. | veditors = Moss D, McGrady A, Davies T, Wickramasekera I | title = Handbook of mind-body medicine in primary care | pages = 359–375 | location = Thousand Oaks, CA | publisher = Sage }}</ref> Electrodermal biofeedback is used as an adjunct to psychotherapy to increase client awareness of their emotions.<ref name="Toomim, M. 1975">{{cite journal | vauthors = Toomim MK, Toomim H | year = 1975 | title = GSR biofeedback in psychotherapy: Some clinical observations | journal = Psychotherapy: Theory, Research & Practice | volume = 12 | issue = 1| pages = 33–8 | doi = 10.1037/h0086402 }}</ref><ref>{{cite journal | vauthors = Moss D | year = 2005 | title = Psychophysiological psychotherapy: The use of biofeedback, biological monitoring, and stress management principles in psychotherapy | journal = Psychophysiology Today  | volume = 2 | issue = 1| pages = 14–18 }}</ref> In addition, electrodermal measures have long served as one of the central tools in [[polygraphy]] ([[lie detection]]) because they reflect changes in anxiety or emotional activation.<ref>{{cite journal | vauthors = Pennebaker JW, Chew CH | title = Behavioral inhibition and electrodermal activity during deception | journal = Journal of Personality and Social Psychology | volume = 49 | issue = 5 | pages = 1427–33 | date = November 1985 | pmid = 4078683 | doi = 10.1037/0022-3514.49.5.1427 }}</ref>