“To err is human”, and telling lies is a part of that error. There are various circumstances under which people lie in order to prevent the worse from happening. Sometimes it may be good and sometimes it may wreak havoc.
Soon the idea of detecting lies came into existence. It was also called as deception detection. Initially, lies were detected using questioning methods carried out by expert people. After certain period, it became easy for people to breach the methods carried out by the lie detection experts.
As the technology developed, the role of detection of lies shifted from man to machines. The machine that is used to detect the lies is called as polygraph.
When a person is taking a lie detection test, several sensors are attached to his/her body. These sensors record the following signals:
- Breathing rate
- Blood pressure
- Body movement (Leg, Arm)
These are recorded on a plain paper which keeps on moving so that it looks like a graph.
But, this is not the test. The real test is when a questioner asks a certain number of questions to the person taking the test. When the test is over, the expert checks the graph for varying signals such as high pressure rate, pulse rate. If there are any significant changes, then it can be confirmed that the person is holding something back. One of the famous destinations for lie detector test is the United Kingdom. NADAC group is the largest private Polygraph Company that provide lie detector test for various situations. Some of the other lie detector test London has includes London Polygraph, UK Lie Detector test, Lie Detectors-UK, north London detectives, Lie Detector Test, etc.
Though there are several tests, there is also a drawback in this technique. The examiner’s questions are subjective in approach and as every person reacts in a different way to lying, so this test can also be fooled at times.