[Quilla]

I've been searching for a source that implies profuse sweating is a sign of lying. Sadly, I'm just coming up with a bunch of nutjobs rambling on about President Bush "lying" about the war in Iraq. Sheesh.

[kcvl]

In practice, virtually all polygraph instruments used for psychophysiological credibility assessment record measures from at least three physiological systems that are controlled by the autonomic nervous system. Recordings are usually made of palmar sweating (commonly known as the galvanic skin response), relative blood pressure (obtained from an inflated cuff on the upper arm), and respiration (obtained from volumetric sensors placed around the chest and/or abdomen). Many instruments will also provide a measure of peripheral blood flow (usually obtained from a photoelectric plethysmograph placed on one of the fingers).

[kcvl]

The type of eye contact variation appears to be different depending on the nature of the deceiver. Introverted liars show a dramatic decrease in eye contact, while extroverted deceivers show an increase in eye contact (Walters, 1996). It is possible that the introverts response is a "flight" reaction attempting to disassociate themselves from the stress of the deceptive situation, while the extraverts bolstered their interpersonal presence via increased eye contact as a "fight" reaction either to challenge the interrogator or because they believed it increased their perceived sincerity.

A less salient and more complicated, yet still predictive, cluster of deception cue behavior are the signals provided by posture and body movements. Horvath, Jayne, and Buckley (1993) created a profile of postural and body movement variations of truth-tellers and deceptive individuals. According to their findings an honest individual typically displays a comfortable, open, and forward leaning posture. The deceptive individual is characterized by a more rigid, generally frozen, and defensive posture.

The rigid and frozen nature of postural shifts and body movements is a consistent finding (Mehrabian, 1971; Vrij, 1994).

It does appear that the deceptive communicator will occasionally show evidence of increased movements. One particular example occurs when an individual is attempting to disguise a channel that they consider more revealing (Ekman & Friesen, 1974). Walters (1996) notes that some of the more common disguising movements include: the covering of ones mouth, or even briefly ones face, to disguise any revealing facial expressions; and secondly the breaking of eye contact during times of particular stress via the usage of an interfering body movement (i.e., adjusting ones glasses).

The typical deceiver also tends to present a posture defined by researchers as "defensive" (Horvath, Jayne, & Buckley, 1993). Typical of this posture is the backward lean, arm crossing, and leg crossing. When an individual is feeling threatened and stress increases, it appears that one often carries out a postural shift into a "defensive" position that acts as a proximal barrier for the individual. This in turn creates a more comfortable, and thereby less stressful, environment.

[kcvl]

Two of the measurements (the rate of breathing and the blood pressure) would suddenly increase when the guilty party was asked a probing question. A third measurement, the galvanic skin response, registered the conductivity of the normally dry skin. The skin has some 2 million sweat glands, which leak some sweat when the suspect was under pressure, and so increase the skin conductivity.

[kcvl]

A team from Temple University last year tested 11 volunteers - some told the truth, some lied - both on a polygraph instrument and with functional magnetic resonance imaging (fMRI). In all cases, the liars were detected by their galvanic skin response.

[No Surrender No Retreat]

Hey Quilla, just ask Al Gore he is the expert. Metabolism speeds up when dicussing information one feels thoroughly uncomfortable with knowing they might get caught lying(guilt)sweating profusely. Normal? PVSD would have been inclimated to the Island tropics along time ago. Why would he be sweating so much if not lying? He is, was and will continue to lie. How are things in Dothan? NSNR

[elli1]

Profuse sweating is a symptom of anxiety.

I think that it is fair to say that PVDS was in a stressful situation regardless. And it is possible that he has an underlying anxiety disorder. In any case, there are other possible explanations other than ''He was lying.''

Anxiety symptoms: For no apparent reason you break into hot or cold sweats. You may also experience hot flashes or excessive sweating for no reason. These sweating periods are more frequent and uncontrollable when under stress or in stressful or important situations such as family gatherings, business meetings, or social situations.