How Does A Lie Detector Actually Work?
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Morning Liars!
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Say you commit some sort of crime.
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There's a pretty high chance you’d get hooked up to one of these:
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A lie detector test, AKA a polygraph.
But how does a lie detector test actually work?
Well, basically a lie detector tests monitor a bunch of different parts of your body.
It looks at breathing rate, sweat level, heart rate and a bunch of other metrics.
But why do they matter?
Well, imagine you're all wired up to a lie detector and your wife starts asking you questions like:
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This makes you start to sweat ,your pulse goes up, and you have a shortness of breath.
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You know you have to lie and your body knows that so you start showing all these telltale signs.
How the lie detector test works:
First, you’re sat down in the chair and then you get wrapped with these 2 expandable tubes around your torso.
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These monitor how often the chest expands, i.e. breathing rate.
Next the officer uses velcro to attach some stainless steel plate thingies to your fingers. Which creates a little electrical circuit.
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See, generally the more you lie, the more you sweat.
The trick to this is that you have a TON of sweat glands in your fingers and when you sweat, a bunch of sodium ions come out of the pores in your skin.
This causes the mini electrical circuit to activate.
So it can basically record how much you're sweating.
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The next step is to hook you up to a regular blood pressure monitor like you might find in a hospital.
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Now, some modern polygraphs also have these 2 other metrics that are recorded.
One is a pad under your butt that records pretty much every muscle movement you make.
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Even a tiny twitch of your pinky toe.
And the other is a heat camera that they put right in front of your face to measure how hot your face gets, another telltale sign of lying.
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Here’s where the test actually starts.
The officer will begin by asking you a couple simple questions like:
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This is to establish a baseline reading for when the subject is telling the truth.
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This is then when they start asking the relevant questions:
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Let's take a look at the results:
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Wowza, doesn’t take an expert to figure that one out.
Looks like you’re going away for a long time, buddy.
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Stay cute,
Reece, Henry & Dylan
Stay Cute,
Reece, Henry & Dylan 🌈
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