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Brain Scans to Identify Liars?

Posted by Zonk on from the hello-mr.-anderson dept.

dotc writes "After a bunch of sci-fi stories and rumors, now it looks like the future has become a reality -- a reliable, unbiased test using functional MRI brain scan to detect lying. The article author details a first-person account of undergoing the MRI 'deception task'. And the test is available now - use it to prove your innocence." From the article: "Laken said he's aiming to offer the fMRI service for use in situations like libel, slander and fraud where it's one person's word against another, and perhaps in employee screening by government agencies. Attorneys suggest it would be more useful in civil than most criminal cases, he said."

10 of 324 comments (clear)

  1. Do not rely completely on fMRI by BWJones · · Score: 5, Insightful

    But advocates for fMRI say it has the potential to be more accurate, because it zeros in on the source of lying, the brain, rather than using indirect measures

    This is completely bogus. Look, if one can lie (and is good at it), it is going to be much more difficult to figure out whether they are telling the truth or not. To someone who knows what they are doing, polygraphs can be fooled and I would suspect that interpretation of fMRIs can also be confused by someone who "knows" how to lie. The trick is to avoid delivering "tells" that are physiologic manifestations of deception. The truth is that there is no foundation in physiology that mandates that one has to reveal anything when stating something that is not in fact, the truth. A good liar will be able to deceive the device and more importantly, the interpreter of the device because they are able to LIVE the lie.

    Now, I am not saying that all means of determining lies by technology are doomed to fail. Rather, I believe that relying on any one (particularly trendy) method for determining lies will work. And the use of fMRI is simply a massively expensive and trendy polygraph, particularly because there are so many differences in cortical anatomy and regional differences between individuals. I would be much more comfortable with a derivative of cortical function such as the p300 cortical recognition waveform used as part of a more complete determination of truth using interview, cross checking of facts, polygraph and p300. Perhaps if the fMRI proves accurate to some degree, it could be integrated, but it should not be used exclusively.

    And yes, I do know a little something about neurophysiologic monitoring as I teach neurophysiology labs to medical students.

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    1. Re:Do not rely completely on fMRI by BWJones · · Score: 4, Insightful

      "You if believe it, it's not a lie."

      This is exactly true.

      I imagine it would be hard to get a warrant for $*00,000 to get some guy tested on the fMRI.

      MRIs are not quite that expensive. We (our family business) charge on average about $2000 with all the costs considered of operating them (electricity, cryogenic liquids, trained personnel, depreciation). fMRI is going to be a bit more expensive than that, but certainly not in the five to six figure range.

      however, the very concept of the 100% accurate lie detector is scary. It would have a huge impact on politics, crime, and even personal issues. "Did you cheat on me? Do you look at porn a lot? Do you think I'm fat?"

      What is more scary is the level of science education of those individuals who will be wanting to use these measures of veracity to determine truth. People are always looking for the quick answer and they are not always willing to put the time or effort into determining what is truth.

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    2. Re:Do not rely completely on fMRI by Limecron · · Score: 4, Insightful

      A well visualized lie and the truth would still be hard to distinguish.

      First off, you make the assumption that the interviewer can know the questions to ask. If someone kills their spouse and there are no witnesses, it's any ones guess as to what REALLY happened. Sure, clues can give some indication (or even a good indication), but if the person didn't leave that much evidence, it's not certain that there will be lots of useful questions to ask.

      Secondly, lots of what you remember IS "made up". You brain only remembers things it deems statistically significant, the rest you remember as "stuff that usually happens". So you can't really ask a bunch of general question and determine it to be true, whether the person is trying telling the truth or not.

      Also, you need to be able to tell what a particular person's brain looks like when it's actually lying. Asking them to state something that is untrue does not necessarily give an accurate profile of how they are when they are really trying to be deceitful.

    3. Re:Do not rely completely on fMRI by MilenCent · · Score: 4, Insightful

      Lying requires more brain horsepower than telling the truth and the parts of the brain used for lying are known. They are different than just recall.

      I'm still dubious. If the subject has worked out his lie ahead of time, as any good liar will, then there is no creativity involved at the time of the scan.

      There is no "part of the brain for lying," just as there is no part of the brain for making an omlette. There are parts of the brain that activate when a lie is told, but a good liar knowing he's going up against such a machine will go so far as to practice visualizing the lie.

      Also, don't forget: creativity is part of telling the truth, too. Our memories are a lot more sketchy than we notice, and we often internally reconstruct events that are not explictly recorded. The human brain is not a VCR.

  2. To quote the genius that is George Constanza by Anonymous Coward · · Score: 5, Insightful

    "It's not a lie, if you believe it."

    What's the MRI gonna tell you then?

  3. Detecting lies is not at all the same thing. . . by kfg · · Score: 5, Insightful

    as detecting truth.

    What's more, they admit it doesn't actually detect lies, because people beat it; and that's under idealized lab conditions.

    Do not go directly to jail.

    KFG

  4. Claimed validity by jm92956n · · Score: 5, Insightful

    The for profit lab reports the test is accurate 90 percent of the time. Even after an independent study is performed, I'm still not sure I'd trust the accuracy. Controlled tests (where subjects are directed to steal an object) are very different than real world scenarios. Regardless, I suspect that, like polygraph tests, courts will eventually rule the outcome of such a procedure is not admissable evidence.

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  5. Re:IANALDTE (Lie Detector Test Expert) but... by Danse · · Score: 4, Insightful

    If the subject truly believes the response to a question regardless of it's validity, there's much you can do in the way of physical monitoring.

    If the subject is telling you what they believe to be true, then they aren't lying. They may be incorrect, but that's not the same thing. This device is useful for detecting when someone is knowingly giving untrue responses. Seems to me it would be highly useful. I'd like to see the Enron execs hooked up to this thing for a little Q&A.

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  6. Implanted memories by Nutty_Irishman · · Score: 4, Insightful

    I'd like to point to: http://www.abc.net.au/science/k2/moments/s1213245. htm

    It's an article talking about how easy it is to implant memories that never existed into peoples minds. In fact, not only do people end up remembering things they've never seen, but they also end up adding additional information to the stories. It's a bit scary actually, but it's a good thought on how one might "break" the system.

    Quoting the article:
    "It's one thing when implanting false memories is a laboratory experiment, but it's quite another when the accused wrongly end up in jail..."

  7. Prove your innocence? by ion_ · · Score: 5, Insightful

    use it to prove your innocence

    Anyone remember the time when you were considered innocent until proven guilty?