Progress In Brain-Based Lie Detection

A Cognitive Neuroscientist writes "A new study, led by Harvard Psychologist Joshua Greene and forthcoming in the Proceedings of the National Academy of Sciences, may represent progress on the front of using brain imaging techniques, such as functional magnetic resonance imaging, to detect lies. According to Harvard's press release, Greene's is 'the first study to examine brain activity of people telling actual lies,' as opposed to prior studies in which subjects were merely instructed to lie. The results suggest that one key step in distinguishing honest from dishonest individuals may involve focusing on a small set of brain regions that are responsible for executive control and attention. However, given that the actual paper is yet to be published, it's unclear whether the study is prone to some of the methodological and interpretive complications that have recently plagued similar brain imaging studies."

Comments

Why all the skepticism?

[eln]

I don't understand why the contributor of this story is so skeptical of it...it seems all we would need to do is hook the scientists up to an fMRI and we'd know for sure if they were lying about the study!

Re:Why all the skepticism?

[girlintraining]

I don't understand why the contributor of this story is so skeptical of it...it seems all we would need to do is hook the scientists up to an fMRI and we'd know for sure if they were lying about the study!

Yeah, except... people have been killed before on the mere suspicion that they were lying about certain things. Adding some scientific air of validity to it will only ensure the body count rises, irrespective of whether it works or not. Plus, we're making guesses about whether a person is really lying based on our miniscule knowledge of the brain -- in truth, we're just playing a statistics game, albeit with potentially fatal results for those who fall more than 3 sigma outside the norm.

Re:Why all the skepticism?

[Foobar of Borg]

in truth, we're just playing a statistics game, albeit with potentially fatal results for those who fall more than 3 sigma outside the norm.

True, but unfortunately a lot of things in society are set up to kill off those who fall more than 3 sigma outside the norm. We just keep looking for excuses to make ourselves feel good about the fact that we are doing it.

Indivual differences

[gurps_npc]

I understand that it takes significant testing to confirm that the machines are working correctly for each individual. I would bet that many individuals - such as psychopaths - could easily beat the machine if they refused to cooperate/pretened to cooperate with the 'set-up' phase.

Let's Pretent

[MyLongNickName]

Let's pretend we had a non-invasive, 100% reliable method of detecting lies. Assume that it is proven to the point where no one argues that it has failures.

Would it be ethical to use them to prove innocence or guilt in a court of law?

Skepticism because MRI doesn't work that way

[sonnejw0]

The results of an MRI scan are composite images of increasing spatial resolution taken over a time span of minutes to tens of minutes. If a person's "liar region" of the brain lit up during a scan, that only means that region was active at some point during the scan, which could have occurred for any number of reasons during that time span.

MRI cannot be used as the sole means of evidence for this kind of study, and papers that rely solely on MRI are seen as untrustworthy or "merely-interesting" at best.

Re:Liar, liar.

[nbauman]

I'd like to compare the fMRI of a researcher telling a subject the actual purpose of a study, with the fMRI of a researcher deceiving a subject on the purpose of the study.

Re:New non-trusive lie detection method flawed?

[vertinox]

I don't see why having a working non-intrusive lie detection method would mean those things have to stop!

Pretty much.

If the victim's... Err... bad guy's MRI shows that he is lying when you finally got the confession out of him just to make you stop the torture means you need to keep beating him until he fully believes it himself.

Now how many light bulbs do you see?