https://www.antipolygraph.org/lie-behind-the-lie-detector.pdf this is also a very good read on a polygraph test. its a long read, but filled with very useful info. when i was on probation for 6yrs, and was required to go to “sex offender counseling” My P.O. was a *rick with a capital P. he made me poly every six months, at my expense of course, @ 350.00 a pop, at the time. it was always a very stressful event for me. not that i had anything to hide, but if i had failed any of them, it could have been detrimental to my probationary freedom. i tried to do as much research as possible on the subject. to be informed, and prepared. two things i learned right away after doing extensive research, and personally going thru multiple polygraph exams. polygraph is suedo science(b.s.) at best, sure they hook you up to measure your physiological changes to certain questions, but that in no way shows whether someone is telling a lie. speaking of lie, your polygraph examiner, may come off as being very friendly, concerned about you or your issue, BUT make no mistake, they are NOT your friend, and in fact, will be less than truthful with you, to try and trip you up during the test. they are trained to get you to lie, that’s their job, that’s why your sitting there in front of them. its a chess game, to see who flinches first. take polygraphs very seriously, but also arm yourself with the tools needed to keep things on an even playing field.