<p>These tests, which are often used as aid during investigations by probe agencies, are different from each other, but are all aimed at collecting vital information.<br /><br />Narco-analysis is a controlled administration of intravenous hypnotic medications called truth drugs on a suspect to procure vital information.<br /><br />A polygraph, popularly referred to as a lie detector, is an instrument that measures and records several physiological indices such as blood pressure, pulse, respiration and breathing rhythms and skin conductivity while a suspect is asked a series of questions.<br /> <br />Deceptive answers are said to produce physiological responses that can be differentiated from those associated with non-deceptive answers.<br /><br />Brain-mapping is a comprehensive analysis of brainwave frequency bandwidths. In this test, forensic experts apply unique neuroscience techniques to find out if a suspect's brain recognises things from a crime scene which an innocent person's brain will have no knowledge of.<br /><br />In brain-mapping, sensors are attached to the suspect's head and he or she is made to sit in front of a computer screen. The suspect is then made to see images or hear sounds.<br /><br />The sensors monitor electrical activity in the brain and register certain waves which are generated only if the suspect has any connection with the stimulus (image or sound).<br /></p>
<p>These tests, which are often used as aid during investigations by probe agencies, are different from each other, but are all aimed at collecting vital information.<br /><br />Narco-analysis is a controlled administration of intravenous hypnotic medications called truth drugs on a suspect to procure vital information.<br /><br />A polygraph, popularly referred to as a lie detector, is an instrument that measures and records several physiological indices such as blood pressure, pulse, respiration and breathing rhythms and skin conductivity while a suspect is asked a series of questions.<br /> <br />Deceptive answers are said to produce physiological responses that can be differentiated from those associated with non-deceptive answers.<br /><br />Brain-mapping is a comprehensive analysis of brainwave frequency bandwidths. In this test, forensic experts apply unique neuroscience techniques to find out if a suspect's brain recognises things from a crime scene which an innocent person's brain will have no knowledge of.<br /><br />In brain-mapping, sensors are attached to the suspect's head and he or she is made to sit in front of a computer screen. The suspect is then made to see images or hear sounds.<br /><br />The sensors monitor electrical activity in the brain and register certain waves which are generated only if the suspect has any connection with the stimulus (image or sound).<br /></p>