What is Narco test? How it differs from Lie detector test.?

Question

What is Narco test? How it differs from Lie detector test.?

Answer 1

A Narco test involves being injected with substances that lower your inhibitions making it more difficult for a subject to lie. Read more here:

http://en.wikipedia.org/wiki/Narco_Analy...

A lie detector test doesn't involve being injected with anything. Instead, a number of physiological responses are recorded when you answer a question. You can read more about it here:

http://en.wikipedia.org/wiki/Polygraph

Answer 2

Both are entirely different tests.

In Narco  test, the person is injected with 'truth serums' that cause the person to become uninhibited and talkative.It is still possible for people to lie under the influence of truth serums, so it is not altogether reliable.

What is used for these tests is Sodium Pentothal, which sedates only for a few minutes. Drugs like Sodium Amytal and Scopolamine are also used.But these tests do not have any legal validity as confessions. The court may give limited admissibility depending on the case.

In a lie detector test or polygraph test, four to six sensors are attached to the person undergoing test. A polygraph is a machine in which the multiple ("poly") signals from the sensors are recorded on a single strip of moving paper ("graph"). The sensors usually record:

The person's breathing rate

The person's pulse

The person's blood pressure

The person's perspiration

Sometimes a polygraph will also record things like arm and leg movement.

When the polygraph test starts, the questioner asks three or four simple questions to establish the norms for the person's signals. Then the real questions being tested by the polygraph are asked. Throughout questioning, all of the person's signals are recorded on the moving paper.

Both during and after the test, a polygraph examiner can look at the graphs and can see whether the vital signs changed significantly on any of the questions. In general, a significant change (such as a faster heart rate, higher blood pressure, increased perspiration) indicates that the person is lying.

When a well-trained examiner uses a polygraph, he or she can detect lying with high accuracy. However, because the examiner's interpretation is subjective and because different people react differently to lying, a polygraph test is not perfect and can be fooled.