Posted on 11/01/2005 12:31:35 PM PST by Willie Green
For education and discussion only. Not for commercial use.
US scientists believe they may be able to develop a more reliable lie-detector test - by listening to liars' stomachs.
Conventional polygraph tests, which are 80 to 90% accurate, use changes such as increased heart rates and sweating.
But people who are telling the truth can show similar changes merely because they are anxious about being tested and others learn how to "cheat" the tests.
A University of Texas study involving 16 people found looking for gut pattern changes was a more reliable test.
Dr Pankaj Pasricha and colleagues told an annual meeting of the American College of Gastroenterology how their test, called an electrogastrogram (EGG), could clearly spot when someone was telling a fib.
They asked 16 volunteers to simultaneously undergo EGG tests and standard electrocardiogram (ECG) - a test to measure heart rate which makes up part of standard polygraph testing.
Like an ECG, an EGG is recorded by attaching painless electrode stickers to the skin.
Gut reaction
The researchers found that both lying and telling the truth affected the ECG recordings compared to baseline measurements when the volunteers were asked simply to rest.
In comparison, the EGG showed obvious changes only when the individual was telling a lie - there was a big decrease in the percentage of normal gastric slow waves.
"Further research in real-life situations and using larger numbers is necessary to validate these results," cautioned the authors.
However, they said their findings suggested: "The addition of the EGG to standard polygraph methods has clear value in improving the accuracy of current lie detectors."
Professor Richard Wiseman, a psychologist at the University of Hertfordshire, said: "It is an interesting idea.
"However, like the conventional lie detector, the technique seems to rely on the notion that people become more stressed when they lie.
"People who do not feel guilty about lying or have rehearsed the lie many times may not show such anxiety and thus pass the test."
Professor Don Grubin, professor of forensic psychiatry at Newcastle University, said: "There's no reason to believe that this would not work.
"The stomach is controlled by the same bit of the non-voluntary nervous system that controls breathing and heart rate and sweating. So we would expect to see changes.
"But a lot more work is needed to determine whether these changes do provide added value."
He said that conventional lie detectors were between 80 and 90% accurate and that, as yet, there was nothing available to beat that.
Ted Kennedy could not pass this test...
Is that my nestegg? I was wondering where it went.
Back in the early 60's I had a 409 Chev Impala. My auto mechanic had a huge beer belly and would rest his stomach on the radiator while he adjusted the carbs. He said his stomach has a special gift to feel vibrations. Best carb adjustment the car ever had.
If some cop asked me "So did you kill your wife", I'm sorry but my gut would go into spaz...whether I said yes or no...I don't see how this test could really be a good test of innocence!
There's a technique- long used by LE in Central & South America- of observing pupil dilation when asking the "zinger" question. Highly inadmissable here, of course.
1) Because his stomach is always growling and 2) Because his mouth is always lying.
I wonder what else this electro-orgasmatron can do. I don't think I spelled that right.
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