Hi, this is Wayne again with a topic “The Truth About Lie Detectors”.
You’Re watching TV, you’re, 45 minutes into a tense crime drama and the cops have their primary suspect wired up to a lie: detector machine. Finally, the truth or maybe not in fiction and on the news. Polygraph tests are often depicted as basically infallible unless you’re a Super Genius serial killer, with the ability to control your heartbeat and every drop of sweat, but in real life. There are plenty of cases where relatively normal non-serial Killers have beaten the test. On top of that, the polygraph isn’t even measuring lies strictly speaking, lie detector is an effective but actually misleading little bit of branding what a polygraph test. Actually, measures are a number of physiological responses that typically correlate with stress respiration, perspiration heart radiation, heart rate and blood pressure. Now lying is typically stressful, even when we don’t feel guilty because deception takes effort and there are consequences to getting caught to take all those readings. A polygraph machine has has several key components. First, is the pneumograph a device that measures a subject’s breathing? There are two major variants of pneumograph. The first uses two sets of rubber tubes, one that circles the chest and one that circles the abdomen these Loops stretch when the subject breathes, thereby reporting the rate of respiration. The second type of pneumograph uses electrical impedance to measure breathing, so the test administrator places two pairs of electrodes on either side of the chest, because nipples never lie. I guess they then run a high frequency, low amplitude current through the subject’s chest cavity and because air is a better electrical insulator than human flesh. The chest blocks more of the current as the lungs expand to measure how sweaty the subject gets when getting grilled a mouse is placed on a desk in front of them and the game no, no just kidding a galvanograph is attached to their fingertips.
This uses electrical current to measure the conductivity of the skin, which increases when damp next there’s the cardio sphygmograph, which uses an inflatable blood pressure cuff to amplify the sound of the subject’s blood flow and therefore heartbeat, recording blood pressure and heart rate. Finally, there’s the data acquisition system or Das, which collects data from each of these subsystems and converts it into a readable form, a bunch of squiggly lines on a paper, readout or well more likely these days, a screen modern, as can even assist administrators through simultaneous computer Analysis of the results. Now that’s a lot of delicious quantifiable data that’s being collected, but does it really mean that we can measure lies and solve crime? We’Ll answer that, after a segue to our sponsor MSI with msi’s Meg x670e Tomahawk, Wi-Fi motherboard, you can up your gaming setup. It’S duet rail power system, dual 8-pin, CPU power, connectors core boost and memory boost, bring you design that is focused on power. You can enjoy a lightning fast gaming experience using the pcie 5.0 slot, lightning, Gen, 5 m.2 and USB 3.2 gen 2×2, and it offers a premium thermal solution with its extended heat, sink design and m.2 shield frozer that are built for Non-Stop high performance system operation head Over to the link in the description to get your Meg x670e Tomahawk Wi-Fi today, one of the most difficult aspects of applied science is just how many potential confounding variables there are in the real world, with the messiest being the human element, polygraphs measure, breathing sweating heart Rate and blood pressure all physiological symptoms of stress, but there are tons of causes of stress that have nothing to do with lying to the authorities, because you had just murdered your spouse. For instance, having the authorities accuse you of murdering your spouse might be incredibly stressful. For that matter, so is jogging drinking coffee, watching a scary movie performing on stage falling down the stairs getting married or being punched, and the human body doesn’t really differentiate. Much between these various sources of stress.
Any of them can turn you into a sweaty stuttering mess. If they’re intense enough for blood pressure readings, there is a known problem called White hypertension, where some patients have consistently higher blood pressure readings whenever they’re tested in a medical setting like a hospital or doctor’s office compared to when they’re tested at home or with those automatic Tests at the grocery store – this is typically because the patient finds going to the doctor stressful many innocent people, then even those who have never had a bad interaction with the police find interacting with law enforcement. Scary and those people are more likely to fail a polygraph. Another problem is that polygraph interpretation is well interpretation. No two people respond exactly the same to all stressors and there’s no hard line between pass and fail. Rather, administrators typically ask a series of irrelevant but uncomfortable questions to establish a Baseline and then they compare that to later more loaded questions about the actual subject of the investigation, but this leaves a major opening for subversion. Subjects who know how the test Works May intentionally speed up their breathing during the Baseline questions or may slow their breathing during relevant questions. Some may take anti-anxiety medication or drink alcohol before the test to mask their stress, while Others May simply walk in confident and retain their cool Aldrich aims.
A chronic alcoholic and a spy for the Soviet Union was given two polygraphs during his time at the CIA and passed both of them. The key advice given to him by his KGB handlers just relax comrade a major Assumption of the test is that these reactions are involuntary and to an extent they are. But almost every everyone outside of the iron lung can control their breathing at least and then from there. It takes a trivial amount of practice to intentionally speed, up or slow down your heart rate, which also affects your blood pressure.
In some ways, the innocent are the least prepared to take a polygraph test, as habitual Liars are less likely to show signs of stress when lying. What this all means, then, is that polygraph tests aren’t terribly reliable better than chance, perhaps but seriously flawed. There’S no firm scientific basis for using these tools to determine guilt or innocence and courts in most jurisdictions have ruled them inadmissible as evidence that hasn’t stopped. U.S law enforcement from using polygraphs as part of their hiring process, though, nor has it stopped some researchers from trying to find a new 21st century equivalent to the polygraph, either through MRI scans of the brain, microexpression, tracking, electrodes, eye tracking cameras or even facial recognition Technologies.
That’S adapted to spot a lie at a distance via security cameras. It remains to be seen, though, whether these new lie detectors will be any more accurate than the old ones. If you enjoyed this video, do a polygraph prove it no seriously hit the like button and if you didn’t you can dislike and if you have any feedback for us leave. A comment maybe run with a favorite.
Outlandish lie: here’s one from us. My heart beats twice a minute like a blue whale, and I haven’t blinked once this entire episode. Don’T believe me go back and check .