Preparing for hot-weather polygraphs and dehydration (no eda/gsr)

If somebody sweats out more than water they drank that day, you may find no eda/gsr activity on your laptop screen.

So it's time to add some new white sticky GSR/EDA electodes to your polygraph supplies!

If you don't already use them, shame on you. They replace the stainless-steel and velcro heads when the fingertips are giving no GSR/EDA tracing due to dehydration or other interference. Two go on the palm of the hand; they bear a snap connector. If you are a busy examiner, you have had situations of little or no GSR/EDA tracings; using white stickies on the palm likely would have cured that.

If you already have some, it's a safe bet that they are past their 18-month shelf-life. Don't let that they still are sticky fool you-- what goes bad first is that the electrode's wet gel in their centers will evaporate, killing the good electrodermal connection.

Vermed (800-245-4025 x1203, ask for 'Pearl', www.Vermed.com) carries the popular disposable types for polygraph examiners. The 1" X 1 3/4" disposable rectangular electrodes (part #GSR-13) are only available in a 1000-piece $163 case order (that works out to less than 17 cents each).

For examiners who have been blaming GSR/EDA problems on their instrument or its software, using white stickies almost always solves the problem. We have observed sxaminers ramble on to excess about faulty instrument software when in reality it was just a dehydration issue that could have been cured by use of 'white stickies'.

TIP: remind examinees to drink plenty of water (not soda or coffee) in the hour or two prior to the exam, to help assure hydration.