March 2, 2004
Been There. Done That. Let's take five with Moira Gunn. This is "Five Minutes."
Traditional lie detector tests have always been a bit "iffy." While used successfully by police departments for investigative purposes, the iffy part comes in when we're told that a determined person can actually beat the test. This is little wonder since the polygraph's primary measurements are heart rate, respiration and blood pressure, the very same targets bio-feedback techniques teach you to control.
There's also the fact that polygraphs involve language. An appropriate set of questions must be generated with the hope of squeezing the test taker into a bald face lie, which can be neatly shadowed by physical readouts running off the scale.
There's no doubt that a better technology would go right to the source. But how can that be? There are no True-or-False-light-bulb sections in the brain. But there is memory and cognition.
That's exactly how a different kind of test is making headway. It shows the test taker information and sees if his brain has prior knowledge.
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Man is a pattern-seeking animal, which has always been essential to survival. Detect a pattern which points to danger, and the adrenalin kicks in before your conscious mind even knows why. We continuously monitor input, trying to determine familiar from unknown, friend from foe. If we've seen what we're looking at before, our brains behave in a very discernable way.
This involuntary and reflexive human trait is at the very core of a technology Dr. Larry Farwell calls "Brain Fingerprinting." Show a person information that could only be known to the perpetrator of a crime, and the criminal's brain will literally give him away. If he wasn't there, that's clear, too.
This technology is well accepted in the neuroscience community, while at the same time a recent report from the National Academy of Sciences called the polygraph into question as being inherently ambiguous.
But in case you think the problem is solved, think again. Plenty of tricky issues still remain.
To date, anyone who's been tested via Brain Fingerprinting is brand new to it. What will happen when a series of successive tests are administered? Who will control what a test taker is shown over time? If you are suspected of one crime, and someone shows you a picture of another, will you register positive for the new image in the future?
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Rigorous, third-party tests are in order, and their scope is not as simple as one might think. Science must not only verify exactly how the technology works, it must also determine correct practice. And legal precedent has no choice but to wait and follow with caution.
This still leaves the federally-funded Department of Defense Polygraph Institute with an especially challenging situation. Founded half a century ago, it offers on-going professional training as well as a fully-accredited Master's degree in what it calls Forensic Psychophysiology. However the name is gussied up, it's still all about the polygraph, a technology whose time may be fast coming to a close.
While Brain Fingerprinting slowly weaves its way through various state courts, it's just the first in a whole set of neurotechnologies just rarin' to come down the pike. So, what would you do if you were an entrenched institution with entrenched methods, and you easily see the next wave of genuinely disruptive technology rising, just ready to break?
For starters, the Polygraph Institute needs a brand new name.
I'm Moira Gunn. This is Five Minutes.
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