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Lying Makes The Brain Work Harder
Ant writes "This Wired News article says it seems to take more brain effort to tell a lie than to tell the truth according to functional magnetic resonance imaging (fMRI) scans. Lying caused activity in the frontal part of the brain -- the medial inferior and pre-central areas, as well as the hippocampus and middle temporal regions and the limbic areas. Some of these are involved in emotional responses. During a truthful response, the fMRI showed activation of parts of the brain's frontal lobe, temporal lobe and cingulate gyrus."
The reason they're seeing so much more activity is because a person who's lying is actively thinking, rather than just "regurgitating" information.
Pretty simple concept IMHO.
I wonder if this study can be universally applied of if it only applies to personal experiences.
That is, if someone wants me to recall a fact from highschool biology, I can probably work hard to remember it. However, I could probably work a lot easier and just make something up.
This sort of thing has happened to me before. My parents once gave my sister and I a math problem, some multiplication of two large numbers. Much to my chagrin, my sister came up an answer the fastest, to which my parents replied "Wow! That's right!" I worked so quickly to try to come up with the right answer, and I fumed about her getting it right until I realized that she had just made up a number...my parents really didn't know the answer either, but by acting confidently like they did, I couldn't see the lies until a minute later.
I'm quite certain that my brain was working a lot harder to do the multiplication than my sister's, which had only to pull a reasonable-sounding number from thin air.
It could be quite pertinent to find out if this were ever to be used seriously as a truth detection mechanism, as it could trip up in some situations, such as for instance a man who's just killed his wife, sitting in his car thinking to himself all the things he did today not killing his wife, essentially fabricating a story or lying to himself. When brought in for a lie detector test you really wouldn't want it showing that a murderer could indeed lie about comitting such an act without any sign showing that he was indeed lying. Of course, this method would be quite useless for questions which the subject hasn't had ample time to manufacture the truth for.
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This would still require some serious effort, practice, and/or ability. Something that did happen leaves a more realistic image in the mind. So to pull something like this off would mean that the lie appears as real as possible to the person telling it. One would literally have to believe the lie to the point of not knowing it was a lie they are telling. Then again, this all depends how much data fMRI can provide and if the scientists can manage to interpret the data correctly. From my knowledge of the brain, it would be far more difficult to fool this, but most likely not impossible. One thought comes to mind, thinking about previous experiences as one is telling the lie might work. If one can manage to say a lie, but ponder on past experiences, it should fool the scientists (unless they use some more complicated ways of questioning the person and interpreting the data). One might need to train for some time to do this right.
Question everything.
Lying may be difficult, but telling "the truth, the whole truth, and nothing but the truth" isn't exactly easy.
The problem lies in editing. For any complex situation, there are several truths that can be said, some relevant, and some not. You have to decide what your questioner really wants to know and think about that stuff.
You also have to turn that stuff into a coherent sentence. In my case, my mind generally works in a very fuzzy way. I don't really categorize things until someone asks me a question, so It is hard to untangle the fuzz and put it in a nice, complete package.
The final problem with telling the truth is the spin. You have to describe things in such a way that you look good and can't get trapped. Like the old "does this dress make me look fat?"-type questions, or pretty much anything you say to your boss.
With lies, these problems kind of solve themselves. When you make up a lie, you build in the spin and story from the start.
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Do you never think when asked to tell the truth? This was a simple test where people knew what was true and what was false. What if you're asked to recall details of an incident 6 months ago? Are you not piecing together information, reconstructing the memory from other snippets you know, retrieving long-buried information? While it may be true that fMRI can detect lies, I'm sceptical of the "common sense" explanation that you have to work more to lie. Furthermore, what about people who believe they have some guilt, but actually don't, say in the case of a death where they're not sure about suicide or murder. Do not the nearest and dearest of a suicide often blame themselves? What if they're asked whether they were responsible for their loved one's death? They might answer yes, even if they were not responsible in the case in question. You can pick holes in that example, but the point is that the whole issue becomes messy when one recalls that people have beliefs and interpretations of situations, and that will significantly affect their answers.
You are right. Intelligent liars create backstories too and just enough details to be believable. Too little details and you'll get caught off guard by questions you have no answer. Too much details pose the danger of inconsistencies and cast suspicion since normal people do not remember every tiny details. Acting and timing are important too. Answering too quickly is a way to get people suspicious.
Your second paragraph is questionable, though. The machine detection does not measure believeability of the lies, rather it measures physical responses. Being intelligent is useless if you start shaking when you tell the lies. I am not saying that there are no people who could escape detection, but it's a different issue altogether.
In the UK you have to tell the appropriate authorities if you dig up human remains and the police got interested because this bog was only a few hundred yards from a house where a woman had mysteriously disappeared about 20 years before. The police had always suspected the husband, but he had always claimed innocence.
The police went back to him and told him that they had found remains and the guy cracked. He confessed to them how he had killed his wife and dumped her body in the bog.
Several months later, the archaeologist got his results back from the lab proving that the skeleton was Iron Age.
Ooops.
You don't actually have to believe it. You just have to have previously constructed the memory in your mind. People react differently when remembering things than they do when creatively "making something up." A common tell is when people glance up and to the left while speaking. This is a common indicator of creative thought. A good liar will have rehearsed or fantasized a lie in their head. When asked about it, they remember what they rehearsed, rather than creating it on the spot. Especially talented liars base their lies upon a true experience to prevent details from tripping them up. This way they do not have to think up anything on the fly.
I'd be very curious to see what is shown in these scans when a well trained professional is put to the test. I suspect they are just detecting how creative thought differs from memory retrieval and that classic lying techniques will fool this new method as well.
just enough details to be believable
I mentioned this in another post, but it bears repeating. A well trained liar does not make up a story from scratch with a certain level of detail. This is a good way to get caught as an unexpected question about a detail may indicate that you are lying. It is best to base your story on a previous experience, even one unrelated to the story. Ideally you should base it on something similar to what you want the interrogator to believe. If you want to lie and say you did not shoot someone when you did, talk about a night two weeks previous to the night in question but with the differences you want to incorporate rehearsed in your mind. By blending a real experience with fiction, inconsequential details are just memories of that real experience, and do not require any creativity. When you say you were at home with a good book, you can easily describe what you were reading about, wearing, eating, etc.