Brain Wave Scanners
Brain-wave scanners (Forensic Science)
Brain-wave scanners are used to map activity in the brain. The patterns seen in the three-dimensional images produced by brain-wave scanning are indicative of whether or not a person is lying. The images are formed using magnetic resonance imaging (MRI). When experts examine the images to determine which areas of a person’s brain become active in response to questions, pictures, or other stimuli, this method is referred to as functional magnetic resonance imaging (fMRI). The subject is placed inside the scanning machine and allowed to interact with a computer screen to answer specific questions related to a crime. The MRI machine is interfaced with special computer software that recognizes specific brain patterns. When a person is telling a lie, the brain has to expend more energy than it does when the person is telling the truth. Even when a lie has been rehearsed in the mind of the subject, the subject uses more brain energy to think beyond the truth and access the lie. The extra brain activity shows up as a “bright” region on the brain-scanned image. In tested case studies, the fMRI method has shown an accuracy of more than 90 percent in detecting lies.
Although still undergoing development and refinement, the fMRI technique has many possible forensic applications. These include situations that involve libel, slander, fraud, or terrorist activities; the technology may also be useful in the security screening of potential employees...
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Further Reading (Forensic Science)
Saferstein, Richard. Criminalistics: An Introduction to Forensic Science. 9th ed. Upper Saddle River, N.J.: Pearson Prentice Hall, 2007.
Tilstone, William J., Kathleen A. Savage, and Leigh A. Clark. Forensic Science: An Encyclopedia of History, Methods, and Techniques. Santa Barbara, Calif.: ABC-CLIO, 2006.
White, Peter, ed. Crime Scene to Court: The Essentials of Forensic Science. 2d ed. Cambridge, England: Royal Society of Chemistry, 2004.
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Brain Wave Scanners (World of Forensic Science)
The term brain wave scanners, in the context of law enforcement, particularly concerning forensic investigations, encompasses an array of research and technological developments that seek to electronically determine whether a statement is true or false.
It has been demonstrated that brain patterns are altered when a lie is being told. Moreover, using a technique called magnetic resonance imaging (MRI), the alteration can be visualized as a lie occurs (commonly referred to as "real-time"). Simply put, a lie can be seen.
The concept of a brain wave scanner is not unlike that of a polygraph. Whereas a polygraph measures fluctuations in heart rate and breathing, a scanner measures brain responses to stimuli. It could be more effective, because a person adept a telling a lie may experience little excitement in the circulatory system. However, even this individual would be required to expend extra energy on the thought necessary to tell a lie, and it is this energy that a brain wave scanner may be able to measure.
When one is asked a question to which one knows the true answer, that answer comes first to mind automatically. Even if the individual has already prepared and rehearsed a lie, it is still necessary to think past the true answer and access the lie. This extra activity is easily measured on a brain scan.
After the September 11, 2001, terrorist attacks, a number of government agencies began to take a new look at brain scanning technology as a means of security screening. In 2002, officials of the National Aeronautics and Space Administration reportedly informed airline officials that they were developing brain-monitoring technology for use in screening airline passengers. Such activity, along with an increase of interest in brain-wave scanning by the Federal Bureau of Investigation, has raised concerns among civil-libertarians, who view brain-wave scanning as a particularly objectionable invasion of privacy in the service of public security.
SEE ALSO Epilepsy; Neurotransmitters; Polygraphs; Radiation, electromagnetic radiation injury.