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Psyc how to detect lie.odt

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Simon Fraser University
PSYC 100
Natasha Ghosh

PSYC100 term paper-How to detect lie Instructor: Natasha Ghosh Abstract Polygraph Eye tracking Facial expression Physicle expression LIWC Truth drug Introduction Our research is based on Lies, their types and old and modern methods of detecting them. First, Lie is an intentionally false statement, and in order to cheat others or making our own profits. People often use to lie at various situations like hiding their faults in offices or schools, to cheat someone, to make easy money etc. There are rare cases in which lies are justifiable or unintentional. For example, lies made when someone do not have enough information about that thing or lies made for sake of others. Mostly, lies create a lot of problem and we need to find to truth in cases like when a truth can save lives of many people. For example, lies need to be detected. The problem arise that how to know that person is lying or speaking truth. How to detect lie? To find the truth, many methods were invented for detecting lies by focusing on blood pressure or muscle movements etc. In 1895, the first person who used science as a method of detecting lies was Cesare Lombroso, the Father of Modern Criminology. He used devices called the plethysmograph and the sphygmograph. The suspicious wore a tight glove, it was attached to a rubber membrane, and this activated a pen that rolled over the surface of a smoked drum. The speed of the pen varied with the suspect’s blood flow. By this result, Cesare believed that, when a person tells a lie, the stress of telling lie affects his or her heart rate and blood pressure. He also developed a machine that measures fluctuations in the blood pressure for police cases. Therefore, by this method of observing differences traced by pen, inquirer can catch the lie of the suspicious. After two years, in 1897, B. Sticker found a new method that could measure suspicious sweat during the inquiry. After that, in 1900’s, Sir James Mackenzie of Scone, Scotland invented an early lie detector or polygraph. The machine invented by him can measure the cardiovascular responses of the patients by taking note of their pulse and blood pressure. Now the polygraph invented by James questions arises, what is Polygraph? Polygraph The polygraph “poly” means “multiple” and “graph” means “to write” is widely used in various fields like medical and scientific settings for different purposes other than detecting lies. The polygraph results are based on the changes happening in body’s physiological activity such as heartbeat and blood pressure. Polygraph is made of various equipments and it measures the changes in the heartbeat, pulse respiration, changes in brain activity, sweat, muscle changes and skin conductivity. . (The British Psychological Society, retrieved from http://www.bps.org.uk/sites/default/files/documents/polygraphic_deception_detection_- _a_review_of_the_current_scientific_status_and_fields_of_application.pdf) The next question arises, how polygraph test are conducted. Polygraph test are conducted by asking various questions to the suspicious from simple questions to specific ones. The recording instrument and questioning techniques are only used during a part of the polygraph examination. It is an examination, which includes pretest phase, questions was reviewed, and technique is explained (American psychology association, retrieved from http://www.apa.org/research/action/polygraph.aspx). The questions were formed on the basis to ensure that the person is able to understand the present situation or not. For example, most criminal cases investigations were done and in this investigation person has to pass through simple to questions that are more complex. For example, person is asked simple questions like “What is your name” or “From where you are”.After this, he or she is asked some direct questions like did you steal diamond? These questions are direct and they know answer of the question. These are just to keep check on the person. Control questions concern misdeeds that are same to those being inquired, but refer to the subject's past and are usually broad in scope; for example, "Have you ever betrayed anyone who trusted you?” such questions stimulate the person and this stimulating help us measure changes in the body and can easily detect if the person is lying.Another example is guilty knowledge test, which is performed on thieves and are asked many multiple choice question. The belief behind this test is that if guilty person know the answer he or she will be more stimulated and will be easy for the investigator to catch the lies. However, there are many controversies related with polygraph test.Aperson who has not done any crime and if investigation is done on him/her, the he may feel more arouse because of his fear which can lead to the false decisions. There are many questions about the accuracy of the polygraph test. The problem with polygraph testing is that there is no evidence that a physiological reaction is unique to deception.An honest person can be nervous while answering questions asked by interrogator and a liar may be non- anxious. Eye tracking There is a new method of lie detection which is called “eye tracking”. It tells that whether the person is lying or not by emphasizing on his or her eye movements. Hatridge and Thompson invent it in 1948. First, this method also used the head movements of the person and then in 1970’s, the theory of eye tracking was linked to cognitive processes. Using eye movement to detect lies contrasts with polygraph testing. The basic difference between polygraph test and eye tracking is found that polygraph test is based on emotional changes where as eye tracking is besed in cognitive changes. The main advantage of eye tracking is that the effort to lie or to deceive others during the test can be seen through the eye movements of the person. In this test, person being interviewed puts a pair of glasses that are attached to the lie detector. Moreover, another device captures the pictures of retina with the speed of 60 photos per second. Then, these pictures are saved in the computer and changes in the retina and pupil is put on the graph. Interviewed person goes through a series of questions of true and false on the computer screen. There are some advantages of eye tracking technology over Polygraph. It is more accurate than polygraph test. It does not another person to interpret the results – the computer analyzes everything. Thus, the results are very objective. It gives very fast results (approx in 30 minutes) and it is very cheap. There are some limitations to eye tracking technology. It is only 82.5% accurate. People who are good at lying know how to control their movements when telling a lie. Psychological disorders can cause problems with data as certain disorders can lead a person to make a statement they believe to be truth but is actually a fabrication. Current research in the field focuses on manipulating the psychological and thus measuring the psychological (University of Utah (2010, July 14). Lie detection: You cannot hide your lying' eyes. ScienceDaily) Using fMRI in Detect Deception Functional Magnetic Resonance Imaging (fMRI) is a technique that using to detect the blood oxygenation. The specific brain area that controlling that behavior will be more active than the other brain areas, when a person doing a specific behavior. In this case, when people were lying, the brain area that controlling people to create untrue statement will be more activity than the other part of the brain, and this is why people use fMRI to detect deception. In 1890, a new view has been published byAngelo Mosso, which is supporting a new developed lie detect technique in 2013. Mosso said, “The subject to be observed lay on a delicately balanced table which could tip downwards either at the head or the foot if the weight of either end were increased. The moment emotional or intellectual activity began in the subject, down went the balance at the head-end, in consequence of the redistribution of blood in his system…"(James, 1890). He has created a speculation that is an opposite view in 1800s, when all the scientists in 1800s thought that a whole brain would not change the blood flow fractionally. In 1948, the basic concept of fMRI have found by Seymour Kety and Carl Schmidt(2013), which show that neurons are using more oxygen when they are active; in addition, the blood vessels beside those neurons will expansion and increase the blood flow in those blood vessels. FMRI is becoming a basically complete technique in 1990s; it is safe and easy for experimenter to analysis the image. FMIR is used in many different areas such as psychology and medicine.As fMIR is analyzing the blood oxygenation and blood flow in brain, fMIR is used for detect lies. Human being can not think without brain; therefore, if we can see how brain is working, then we can know if people were lying. FMIR is absolutely using to detect deception, and also it is a high accuracy and safe brain test. However, fMIR has two small limitations, the first one is that people cannot bring any metal around the machine when it is active, the second one is that it is immoveable, so we cannot use fMRI to detect deception on street(Meda, 2009). Daniel Langleben is a psychiatrist at the University of Pennsylvania, and James Loughead is a neuropsychologist at the University of Pennsylvania, there is a research of Langleben and Loughead shows that there are a few parts of brain will be more active when people are lying. They claim that, when people are lying, the inferior frontal gyrus and the inferior parietal lobe and bilateral frontal cortex are those parts that will be more active (Meda, 2009). In this case, when people using the fMRI to detect deception, they are going to find if those areas are more active than the other areas, the person who was testee has a high percentage that he/she is lying. As a technique of detecting lies, fMRI have high accuracy and no damage to human body, which force it to a new height to be mainstream deception detection. Therefore, the liar in law enforcement agencies would no longer exist and the judgment in court would be justice. Voice StressAnalysis In modern life, deceptions are around everyone, especially in police office, criminal would try their best to lie on police officer to escape from charge. Therefore, police need to have something that can detect whether a person is lying or not; additionally, police need to distinguish a testimony from a witness is reliable or not. Voice stress analysis would also be a good method when the deception detects need to be covertly and it can be used over the telephone for banks and insurance companies (Damphousse, 2008). Nowadays, a great number of law enforcement agencies in United Stated were using this kind of voice stress analysis machine; however, there are some research shows that the voice stress analysis machine is not having a high percentage on credibility (Damphousse, 2008). Voice stress analysis software is detecting lies by analyzing the suspect’s voice patterns and tone. It sounds like that it is a great method to detect lies, but actually it is not really a great method. In a research by Oklahoma Department of Mental Health and SubstanceAbuse Services, 300 suspects were arrest by drug using and test the voice stress analysis software. By comparing the data of urine drug test result which is reliable and the voice stress analysis result, fifteen percent of the voice stress analysis result was wrong presented (Damphousse, 2008). Why voice stress analysis is less reliable? The answer would be the high number of influence. The result of voice stress analysis would easily affected by the environment in which would influence testees’emotion and make them feel stress. People would feel stress involuntarily when they were in some sp
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