Polygraph testing, also known as a lie-detector test, is typically used for employment screening for government careers, like the police force. They can also be used for employee theft testing, special events, infidelity, wrongly accused claims, criminal testing, personal testing, and numerous other reasons.

For those who have taken one, or will take one in the future, polygraph testing can be extremely stressful and nerve-racking. The major reason for this is because most people don’t understand how a polygraph works.

The polygraph or “lie detector” is an instrument that measures and records physiological responses like breathing rate, pulse, blood pressure, and perspiration. The underlying theory is that when people lie they get measurably nervous about lying, which is how it can be determined that they are in fact lying.

The most intimidating part of the polygraph test is being hooked up to the sensors that will collect the physiological data from the human body. Once you are attached to the sensors, the exam will most likely start with a pre-test interview to gain information that will be used for control questions. Meaning, the examiner may ask you to deliberately lie to test your responses, that way they can determine the similarities of your physiological responses to the actual test. They will then administer the actual exam.

Make sure you are well-dressed, well-fed, and well-rested before a polygraph exam. Answer all questions truthfully to the best of your ability— it is better to respond with a truthful answer that the examiner might not want to hear, than to lie.