When a crime has been committed, the usual modus operandi for police detectives and their fictional counterparts has been to dust the scene for fingerprints. And once they have a suspect in custody, out comes the polygraph, or lie detector.
But in today's forensically sophisticated, "CSI"-influenced world, polygraphy - which bases its results on functions of the autonomic nervous system - is increasingly dismissed as dated and unreliable. Rapidly replacing older truth-seeking technologies are new brain-based techniques such as functional magnetic resonance imaging (fMRI), and the electroencephalography(EEG)-based technology known as Brain Fingerprinting®.
Because they are "brain-based," both methods have been promoted in the media as being more precise, accurate and trustworthy.
"Functional magnetic resonance imaging and Brain Fingerprinting® have been hailed as the next, best technologies for lie detection in America, particularly in the context of post-9/11 anxiety," University of Illinois professor Melissa Littlefield says in an article published in the May issue of the journal Science, Technology & Human Values.
"Far from describing the brain and its functions, fMRI and Brain Fingerprinting® produce models of the brain that reinforce social notions of deception, truth and deviance," she concludes in the paper's abstract.
In other words, Littlefield is unconvinced that the new technologies are necessarily superior to the old ones. In fact, the professor of English and of kinesiology and community health believes polygraphy may have more in common with the new technologies than many scientists - particularly neuroscientists - would suggest.