The Science Behind Lie Detector Tests | How Do They Do It?

Find out the history of lie detectors, and how the modern polygraph machine works to catch people lying.
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[@gplgs4640]

“Your hands are sweaty, you’re lying” “Sir, it’s 83 degrees in here with no air conditioning, of course my hands are gonna be sweaty”

[@mayainverse9429]

and they tell you are going to prison for the rest of your life if you fail this test. no pressure

[@PouLS]

How are they alive at 83 degrees? Are they in the middle of Sahara?

[@ajoungajoung3322]

@@PouLS it was 95 where i am and it will be 101 tomorrow. It's really not that hot imo

[@archishman4073]

@@PouLS Fahrenheit

[@PatchworkRose567]

I would never be able to pass a lie detector test bc of my anxiety. My heart rate would be through the roof.

[@Skye416]

Oh god me to

[@tckteamcoolkats2924]

That’s why he asks control questions

[@SlazeM7]

@@tckteamcoolkats2924 Consider the difference in questions: "Is your name ____?", "Are you sitting right now?" vs "Did you murder that family three months ago?" The latter is likely to evoke an emotional response in any person regardless.

[@eddieneil120]

NatureGirl567 I just got done watching The Try Guys second lie detector test video and I’m just sitting here thinking, this test is absolutely flawed to all hell lmfao I’m just saying fam 🤷🏼‍♀️😂

[@aoeu256]

The people who made the lie detector test should take the lie detector test...

[@mayainverse9429]

the ironic thing is the most dangerous types of people can pass these things with flying colors because they don't get nervous for these kinds of things while the most good hearted people are most likely to fail. like they said in this video a serial killer passed with ease and later they pinned the crimes on an innocent guy who failed the test.

[@danielas498]

Some criminals are so emotionless and actually believe they didn’t do anything wrong believing their own lies and being relaxed

[@reyphobic]

when you tell yourself a story continuously, you start believing them. It could be an innocent lie too but the rule applies everywhere. Of course some criminals pass this test because they don't believe they've done anything wrong

[@aspenmangamingwt5403]

So they just assume that because of the blood pressure and your breathing and sweat level. So if your just nervous and you never lied they just assume you lied. BS if you ask me

[@benjymonkey3163]

it is BS that's the point. its all psychological, to make people , and criminals, think that they have something on them and then they are more likely to confess. kinda just a mind game.

[@postmelon645]

I think its bullshit too. However they do ask control questions to see the baseline characteristics even if nervous. The heart rate might go even higher if a person lies

[@edgarz7330]

Cheers for the Video clip! Apologies for chiming in, I am interested in your initial thoughts. Have you researched - Parlandealey Passionate Love Process (Have a quick look on google cant remember the place now)? It is a good one off guide for learning how to attract the right man and avoid cheaters without the normal expense. Ive heard some pretty good things about it and my BF at very last got excellent results with it.

[@aspenmangamingwt5403]

Son Lê Hoàng just stop you and this other guy posted the same exact thing not interested in it

[@aspenmangamingwt5403]

pavel mihai fuck off ur the same person stop

[@AngusWd]

Your fate is in the hands of a computer, makes me feel super safe and secure

[@mayainverse9429]

no its worse than that. your fate is in the hands of an incompetent practitioner of this pseudoscience. before this video i saw a video that looked like it was made in the 80s by a investigative journalist they hired 3 companies to give lie detector tests to some of their employes that someone might have stolen a camera all 3 of the companies got the wrong person and the thing is each time it was the exact person they told the "expert" before hand that is who they expected. even if they "graph" showed things correctly it could very easily be explainable that the demeaner in the questioner in this scenario asked different questions and/or with a different tone to the person that was "suspected" witch in return caused those people to pick up on it and become more nervous.

[@electricheisenberg5723]

@@mayainverse9429 you know who hates lie detectors? most people. and the guy who invented them. fuck lie detectors.

[@arielperez797]

Computer: whatttt? You don't trust me? Also....can you prove you're not a robot by solving this puzzle real quick? 😅

[@odiliamillan5632]

This shit is about as accurate as a toddler taking a 12 grade math test

[@groundshaker6516]

It’s totally failed method No accuracy at all It’s my personal experience

[@ZHP330]

I'll second that.

[@itzolie]

Polygraph results are not admissible in court. That should tell you all you need to know.

[@queenofthenight3518]

Many people sweat and have a high blood pressure under pressure and they don’t have to lie.

[@iudexe3103]

I mostly like to sweating bullets when my body are strapped with this machinery craps whether I'm lying or not

[@johnbhai7147]

Funfact: The credited Inventor of Lie Detector was also the Creator of Wonder Woman... Along with the help of his wife Attorney and Psychologist Elizabeth Holloway, William Marston develop a lie detector in 1915. He was also a psychologist and took his wife as an inspiration for Womder Woman character.

[@Ruessavel]

I love how they mention one guy back in the day who got away with a lie detector test, quickly insert that he killed 70 people, then IMMEDIATELY CUT TO THE NEXT SCENE WITH NO ELABORATION. WHAT?! WHAT DO YOU MEAN!?

[@mayainverse9429]

naturally people with sociopathic tendencies will be capable of passing these with absolute ease. the funny part is later on down the road they actually arrested a guy for those killings because he failed the test. guess what kind of guy he was. a good Samaritan who wanted to try to help with info he had.

[@kelvinlopez4792]

@@mayainverse9429 it’s cause they believe what they say is true

[@Destro_Enough]

The more you lie, the more you sweat? My hands are sweaty, bro.

[@jmcnutt730]

I’m pretty sure anyone would have an erotic heart rate and sweaty hands even if you’re being accused of something you didn’t do

[@mr.benjamin2478]

I passed one years ago. I was guilty as sin. Just make yourself belief the lie and relax.

[@Someone-lh2lt]

😂😂😂

[@BlackTeaShirt]

😂😂 the area 51 thing almost got me there

[@blessedfela1515]

I would only pass this if they did it without me knowing, otherwise once they tell me we are doing it, that would be it for me

[@anything.but.carrots4769]

My anxiety with my excessive sweating won’t let me pass through a lie detector test

[@sparkletoppop]

Very informative video 👏🏽

[@ToxicAvengerCleanYourMind]

Even a question can make your heart race so imagine if out in the woods someone asks you, Did you just see that bear!?.. your body would react even when telling the truth that you didn't... So if you're innocent in a murder but ask you, "Did you kill them" a lot of people would react to such a scary question and get nervous whether you did, or didn't ... Especially when beforehand they ask you softball questions like "Is the sky blue"... Plus, I bet if they ask you that most people could lie and the machine wouldn't pick it up because it's the question that would make a person nervous, not whether the lie or not.

[@nextlevelangling3705]

Okay these things are so scientifically flawed. You’re telling me if my hands are sweaty that I’m lying?😂😂 this is so stupid they shouldn’t be used at all

[@Kellypet1]

Just explain it! Not everything has to be a fake reality tv show. Dun dun duuuun. No, just say it! Frick sake! This was so dirivitive!

[@roselmarianalboria6116]

This could be a great escape to all pathological liars.

[@prettyboi89ify]

Steve wilkos show brought me here

[@choppary9151]

Same🤣🤣

[@prettyboi89ify]

yxung Ryan lol😂 glad im wasn’t the only one

[@harrasingh998]

Same lol

[@prettyboi89ify]

@@harrasingh998 😂😂😂

[@KimKim-kk2ly]

Same😂😂

[@TheLoobis]

2:30 The more you lie, the more you sweat? THAT'S HOW IT WORKS!

[@craigtyrrell4515]

i love how people put tips on KZbin how to beat a lie detector allowing any criminal to watch these videos and then they just get away with it😂

[@abhishekbaba7823]

you said the the engineer was developing a mechanism from which he will take a subject's face's temperature to make a guess about lying. Any update on that?

[@superspeedstergaming20]

Just imagine daredevil can do all of this without the machine 💯

[@salowoonton9922]

All those symptoms can be expressed with any question can't they?

[@gingervirux8963]

What I'd Im always sweaty under pression,but aim not hiding anything?

[@shutdahellup69420]

Who the hell in India came up with that? like oh lets make that person chew on rice! why?...why not???😂

[@Hproawesome]

But what if your pretending to stress out on purpose even your telling the truth? Does that still count as a lie?🤔

[@beetogarcia9983]

“Hooston Texas”

[@flipnasty2296]

Its the questions that get you lol

[@thesourpatchkidd579]

So lie detector tests monitor the bodies responses to telling a lie. They kind of gave us the watered down version (it is a 5 minute video) but it makes sense. It's not a flawless system- obviously anything built by man can be destroyed by another- but it makes sense. Not 100% accurate but most of that comes from people who lie and don't get caught and not the other way around.

[@matapangguy3331]

Came to watch this after watching a marathon of Steve wilkos show, I am now skeptical of the shows legitimacy

[@RENEIND]

Don't they test them multiple times

[@predatorhunter3169]

Same

[@drummerboynavarro2893]

Am from Houston Texas is not called huston lol

[@robaelectronics9943]

please everybody who can tell me the specification/datasheet of this machine?

[@prayse8292]

Unless he's talking about a different country in the beginning lie detector test are not allowed in court or for a trail

[@ashmaetwaroo1412]

Wooh! Bravo

[@matthewmeech6194]

Not actually how a polygraph is done, it takes hours, half of the testing is the tester asking questions and gauging your responses before hooking you up, then if they THINK you are lying they ask you after the mechanical testing and use that in addition they constantly tell you the machine is really accurate and you can't cheat it etc. But in reality it is at best 60%effective in field conditions but they always quote 90%+ as that's the lab conditions

[@thawkxing]

Everybody should look up Dan Caputo at the Arizona Department of Public Safety. He's the polygraph examiner there, and he gave me a polygraph that was so degrading that I was diagnosed with PTSD because of it. He's a truly sadistic individual who thoroughly enjoys humiliating and embarrassing people. Those who are selected for jobs with police departments are chosen in the image of people like him. Everybody should please consider emailing or calling Arizona state senator John Kavanagh and expressing support for Senate Bill 1058, which would ban pre-employment polygraph screening in the state.

[@officialhooded]

Oh shoot bet

[@leviparam]

I easily get nervous, I wanna try this if it's really works

[@joshuayoung2024]

Im have severe anxiety and extreme OCPD. I would fail the control questions and be considered unreliable.

[@Cosmicmiind]

Even if you tell the truth you still could be labelled as a liar .. ppl might have conditions .... so just based to assumption and collective data doesn't necessarily give you the real accurate picture..

[@limitedgamer5278]

0:05

[@NitroBladee]

“Your hands are sweaty, you’re lying” Try hard gamers who don’t lie: *nervous sweating*

[@nocturnalsingularity3138]

The government isn't stupid. They KNOW that lie detection machines do not actually detect lies, they aren't even looking for lies. The government, is looking for a certain personality type. That personality type generally does Good Under Pressure, stressful situations, that person can stay calm and collected even while hooked up to a machine. They are not detecting lies, they are detecting personalities

[@ravindu-]

Hope the lie detector creator’s wife got one

[@greenlord9103]

Currently watching this so that I can dodge a lie detector test.

[@johannesofiesteine4206]

I want to learn more trics about how to pass a lie detector test 😀

[@Rahul_Lata_]

the most accurate lie detector have only 86% accuracy

[@Dero_milsurp]

RahulByte it’s only like 50% actually.

[@marck8899]

They are nowhere near as accurate as you give them credit for. You can go in and pass one today and fail tomorrow. The “toss of the coin” accuracy, that is exactly what is stated in some ruling of the USA Supreme Court documentation on why they are not admissible in legal matters.

[@aoeu256]

@@marck8899 Yeah, but they can be used by prosecutors to get people to accept plea bargains.

[@marck8899]

aoeu256 They are ruining lives and reputations every day. People “failing” for government job exams and naive people getting scammed by their narcissistic operators to settle trust matters with absolutely garbage measurements as far as deciding truthful or deceptive answers. You are absolutely correct as far as getting confessions from scared criminals who believe they actually work.

[@schwuppdiewupp7]

This is like something you have to try out by yourself to believe it

[@lemurvids7407]

cool

[@MrhandlerE]

Can you pass a lie detector test by staying calm?

[@vaper8824]

I got anxiety from this

[@user-fw8ph2gg3b]

i was using an apple watch to check my heart rate. my heart bpm was 86. I thought of my crush and it reached 124 bpm

[@drahunter213]

For some reason I thought the brain was monitored for brain responses…lol so that’s not a thing?

[@kartell6650]

Me with a bag of skittles in my pocket: Walmart employees: did you take sum skittles you didn’t buy? Me: ummmm no

[@Mark--__--]

So i can just twll the truth and start acting nervous and it would say im lying?

[@k-out5772]

Why do you love futanari?

[@jaysea7688]

Just believe your lies like how you believe the truth

[@tashliketrash9350]

Jay Sea you can never truly believe you’re own lie because you’re the one who made it and you know it’s not true lol

[@Tyhymn]

Tashai Small it’s a psychological method u have to do. It is possible but not to that full extent

[@levibernier1804]

The inventor of the lie detector had a iPhone 4 in 2018 that’s nice to know

[@blake1713]

I know several people who have taken a polygraph test and they say it was awful

[@chillywillye3990]

It is... And it is more when you "fail" after being totally honest.

[@bibiefayahhh1667]

But what if u get nervous . N have anxiety .... Hmmm

[@Dero_milsurp]

Bibie Fayahhh then you’ll fail every time. Even when telling the truth.

[@wizardboy724]

Having to take a polygraph to prove my innocence in court! Not worried because I’m telling the truth

[@jungarcia137]

Those are just physiological things. What if you have a mental illness? Anxiety? Phobias?

[@deguzmanacp.stem-1655]

What if you’re just nervous

[@christiannielararao8255]

Doesnt matter. If you're nervous the whole interrogation then it wouldn't matter.

[@joghnlogan2472]

gladys jaclyn soto posted 1 video

[@japhethishaku6513]

if only it was created by man and man is not perfect, it equally make the machine imperfect

[@davidbrisco6360]

There's no suck thing as a polygraph machine they actually hook your brain up to a computer without you knowing while your taking it lol vital signs have very little to do with the whole thing and it sends a signal to the computer so remember your brain is a computer and the two devices talk lol.

[@tercidukcacing2689]

so if i just keep calm i will be okay?

[@codyethan5370]

Hi John Larson

[@user-id5rm6qq8s]

I think that we should stick with the rice method

[@wandafranks6177]

I'd just take a huge sump an be like sory nervous

[@Fluffykunn]

With recent A.I. advancement to basicslly read peoples minds, I worry how secure out own thoughts are our own. Get asked of a "false crime" and end up getting convicted of a thought with no intent. Trust I'm not one of those nuts, there is open data on this for disabled people which fortunately/unfortunately opens thay door

[@antiquefuturistic]

Any person with any emotional issues such as BPD, personally disorder, social anxiety, depression, over thinking, worry etc. Will fail this test eventually. No wonder its flawed all over. The person who invented it was with limited knowledge of causes of human’s emotional reactions in the body

[@campconverts]

Was this programme made for kids?

[@timwilde4200]

Can anyone tell me how the results are stored for later use? Whether it's the police, a government agency, etc, they obviously need to keep a record of the examination, so how do they do it? Is it a case of the resulting graph readout as one file, with the audio or video signal of the interview as a separate file that has to be coordinated to match the readout? Or is it all kept together as one file? I was just curious in how they coordinate it in terms of playing it all back so they can see or hear the questions matching up to the graph readout being shown on the screen during the process. Is there like a split screen so they can see the video of the person being examined, with the graph readout results showing in the other half? It's my understanding that the test subject has to be in view through the whole process to make sure they're staying still and not pulling any tricks, like digging their nails in or biting their cheeks. If an examiner were doing a cold read of the results later and couldn't see the video of the person at the same time, it would be harder to get an 'accurate' reading, for what it's worth.

[@jeaux42069]

Hoostin

[@ekoi1995]

are they accurate?

[@flipnasty2296]

I've beaten a polygraph test.... well 3 of them

[@arielperez797]

Wonder what would happen if you messed up your baseline horribly, on purpose, just to throw everything off.

[@wandafranks6177]

I have the shitssorry pinching g to keep from cracking

[@gokulnathrajendran8793]

Make this mandatory for all the politician's public speeches please. The world would be a better place very sooner

[@wawasupremacists3438]

Theoretically just take a beta blocker and ur good.

[@antoniodowling3951]

“hooston”

[@Destro_Enough]

If they're lying, their mouth would be dry? Wtf I will never pass this even if I'm not lying at any cost, I would be stressed, nervous,. You know the feeling of "when you see the police officer in public and even though you didn't do any crime, you try to act normal forgetting YOU ARE NORMAL" This is me. I don't believe in this machine at all.

[@kateoconnor1307]

Pad for the butt what if you have BFS where you always twitch that's not fair

[@wandafranks6177]

A gun and a man with no conscience is a good lie detector

[@milesthecat17]

Be honest who is here because we want Noah and Dixie to do this

[@fourtynineangeles8093]

imposible just a waste of time, no machine can do that ☠

[@greenlord9103]

It won't work to people who even believe their own lies.

[@rodneywatson7425]

Bruce bro, who hurt you

[@rustyknott-W.D]

The whole premise of the polygraph is based on false assumptions about physiological reactions to stress. Who decided these assumptions? The polygraph is not scientific because the results cannot be repeated with any degree of certitude.

[@carsonfarist8590]

I just have to say you will never be able to lie because the LORD up above knows!!! He saved and changed me and will you also if you let him!!! Turn to the LORD and have all amen hallelujah praise GOD!!! Keep doing for the LORD using your special gift amen hallelujah praise GOD don’t give in!!! You will be rewarded amen!!!

[@thedarknessunderneathpodca6366]

Except I know for a fact it doesn't work...

[@tokyo_kero]

Is this scientifically proven? Will room temperature affect the results? Do they consider the person's condition prior taking the test?

[@timothymiddleton6651]

No, same way that inferring honesty from body language is not a science. We intuitively know that we can make useful assumptions though.

[@bijotitus3251]

I'm an Indian, but I've never heard of that technique 😑😑

[@odiliamillan5632]

That makes no sense just because your indian doesn't mean you know every detail about India's history