Often seen in both serious and comical situations in the likes of James Bond and the comedy movie Meet the Parents, lie detection enables the truth to be found in many situations.
Using a range of methods including assessing eye movements, voice analysis and general body reactions, questions can be asked and if a false answer is given the real answer may be found out in a matter of seconds.
The Polygraph detects any changes in the body from the point before asking a question and directly after the question is asked. Body functions that are not easily controlled by the conscious part of our brain can be picked up, such as changes in heart rate or breathing rate. In America, evidence can be taken from information gained through a Polygraph test.
This method detects changes in brain waves and is also accepted in court rooms. It is apparently 99.9% accurate and can determine the honesty of a statement, and works by asking questions to the subject and monitoring how the brain waves appear. Lack of a certain brainwave called P300 means the subject has no recollection or familiarity with the questions being asked, meaning an answer of “no” should be taken as that.
Eye movements and direction
Another – yet far less clear-cut – way to discover if a person is lying or not is to monitor how their eyes move when they answer a question.
If you move your eyes up and left this indicates you are trying to construct an image, for example if you were asked to “imagine a bright yellow cow”. In contrast to this is up and right, which indicates you are trying to remember an image. An example would be “what colour was the front door on your first house?”
Looking to the left denotes the respondent is auditorily constructing a sound they may have never heard of before. For example, “sing the highest possible note.” On the contrast, looking to the right means the respondent is auditorily remembering a sound. An example of this would be “remember the noise your phone makes when it rings.”
Looking down and to the left means you are trying to remember something. A question to prompt this reaction may be “can you remember the smell of burning wood?” And finally, the contrast to this is looking down and to right, which is when someone is talking to themselves in their head, internal dialogue sums this eye movement up.
Although these methods aren’t foolproof, they do provide an interesting way to test if someone is telling lies!