hello all i am just here to tell you all that its all in controlled breathing.  if you control your breathing there is a great chance you will pass 100%.  controlling your breathing lets you controll your heart, pulse, and other bodily functions that may occur when you "lie"----  my advice is to practice breathing techniques a day or 2 before you take the actual polygraph and if you do feel yourself getting tense while testing take about 5-7seconds to get control of your breathing once again and then answer.  (just dont make it obvious)