What is Polygraph Lie-Detection?
Polygraph is a generic name for an instrument which is commonly known as a ‘Lie Detector’. Contrary to popular belief, it does not record directly whether a person is lying or telling the truth; it records changes which take place in the body during stress.
A Polygraph Instrument is, in effect, a sophisticated piece of medical equipment which measures autonomic nervous reactions which take place in the human body when an ‘important’, or incriminating, lie is told. These responses are usually not visible to the eye. The physiological reactions which occur when a person tells a lie are measured by recording respiration, cardio-vascular reaction and skin moisture changes.