MRIs That Read Your Thoughts

Nicholas Roussos writes "Functional MRIs have been used in several studies to accurately predict what volunteers were looking at even when they themselves were unsure. According to the BBC, 'When two images were flashed in quick succession, the volunteers only consciously saw the second one and were unable to make out the first. But the brain scans clearly distinguished the patterns of brain activity created by the "invisible" images.'"

Comments

Hah!

[SwimsWithTheFishes]

If they use that MRI to read my mind, they all will go blind!

Exciting?

[Anonymous Commando]

"You could use it to detect people's prejudices, intuition and things that are hidden and influence our behaviour... it is exciting."

Ok, I'm not normally part of the tinfoil-hat brigade, but this guy scares the living hell out of me...

Stay the hell out of my mind, we don't need the thought police.

Re:Exciting?

[mchawi]

You read my mind.

Re:Exciting?

[oever]

they could tell what a person was thinking deep down even when the individual was unaware themselves.

How Zen is that?

Re:Exciting?

[Anonymous Coward]

1) Look. Have you seen the size of MRI equipment? Who could sneak that on you?

2) Can you read? "You could use it". Don't you realize by now that 90% of headlines and soundbites (for EVERYTHING, not just /.) are ridiculously overstated for effect? Like those people who claim to be learning 40 languages, so you think they'll be as fluent in 40 languages as you are in english, but in reality, they're learning "hello" in 40 languages? Or like this MRI claim, probably made by a university student so s/he can get his paper?

Do you really think we (the human race) has the knowledge to decode thought patterns on a wholesale basis? At best, you can correlate ONE PERSON'S prejudices to a certain pattern on a certain MRI, but only because you already knew the result before hand.

Very exciting...

[RM6f9]

C'mon! I mean, who hasn't secretly harbored a desire to hack the most complex OS we know of, the one that (mostly) resides in approx. 3 lbs of wet-ware? Being able to identify responses to specific stimuli with *objective* accuracy is a HUGE step - next will be cross-subject verification of which portions of the patterns are stimulus-specific vs. subject-specific, then the massive database project of "These signals equal these thoughts", then direct brain language (independent of verbal languages)... On a different track, we'll have signal transmission direct to brain, and THAT's when my tin-hat goes onto my head.

Yes but...

[Cyclotron_Boy]

to quote TFA "That's a long way off, but it is exciting." It is indeed a long, long way off. Specifically, the experiments involved only detected & predicted what the brain was seeing. The predition part was only demonstrating that the brain might see something, but not understand/decode immediately. The computer detected the visual input, but the brain didn't process it. This is a long way from predicting prejudices, fears, and phobias.

But on the other hand, we might not be cognisent of subliminal cues that trigger anger, fear, rejection, etc. in the brain, but the computer might be able to detect the triggers more readily/quickly/reliably. Who knows? We (and Big Brother) will have to see...

and the ubiquitous "I for one welcome our mind-reading computer-aided MRI overlords."

They totally misunderstand their own research.

[Elwood P Dowd]

A team at University College London found with fMRI they could tell what a person was thinking deep down even when the individual was unaware themselves.

This research may present novel information, but this is not what you were "thinking deep down". Many parts of your brain do their processing automatically and without conscious intervention. If you break the part of your brain that identifies objects visually for cognition, but do not break the part of your brain that identifies objects visually for physical use, you can use objects that you cannot consciously identify. You could use a kleenex without knowing that it was on your desk ahead of time.

It should be completely unsurprising that without being aware of an image being flashed, other ("unaware") parts of your brain are doing things with that image. That doesn't mean that it's what you were "thinking deep down".

"This is the first basic step to reading somebody's mind "

Researcher Dr Geraint Rees

This quote is in reference to fMRI detecting whether you are paying attention to vertical stripes or diagonal stripes. It is well known that parts of the primate visual cortex are dedicated to identifying verticle and horizontal lines. This is like saying that Neil Armstrong's first breath was the first step towards Alpha Centauri. Yeah, maybe. Maybe not.

Re:They totally misunderstand their own research.

[Pinefresh]

Or maybe the BBC misunderstands the research. Or maybe they're trying to make it simple enough for everyone to understand.

The BBC article is a common kind of media fraud...

[Futurepower(R)]

The BBC article is a common kind of media fraud, in my opinion. The BBC, to make its article more interesting, has vastly over-extended what the science shows. The researchers themselves commonly participate in this kind of fraud, as is shown in this quote from the article,

"When volunteers were shown a plaid pattern made up of two different sets of stripes but asked to pay attention to only one set, the program was able to tell which one the subjects were thinking about."

"Dr Rees said: 'This is the first basic step to reading somebody's mind...' "

Complete baloney. It was the first step toward detecting what someone was doing when they cooperated fully.

Fraud, fraud, fraud. BBC, you should be ashamed of yourself.

Unfortunately

[Corpus_Callosum]

Unfortunately, any behavior that is learned rather than instictual will show pattern responses that are unique in every brain. It should be possible to map out sexual response, hunger, pain and other instictual (read: built-in) programming.

But a database for other stuff would be person specific. A general purpose mind-reader is unlikely to happen anytime soon.

Some info on fMRI

[ControlFreal]

I work in the analysis of fMRI data, so it might be good to disspell some myth and provide some key info.

fMRI is derived from "normal" MRI, and in fact, any fMRI scanner can also make a normal MRI. MRI, or actually, NMRI, stands for Nuclear Magnetic Resonance Imaging. The "N" for Nuclear is usually not included in the abbreviation because it seems to make the public nervous. An MRI makes an image by using a radio-frequency magnetic field to excite a magnetic spin-state in the nuclei of hydrogen atoms (i.e., in single protons); the more an area resonates, the more the measured signal is modulated, and the higher the hydrogen concentration assumed to be (typically that means: the higher the water-concentration is). Imaging can be done on a three dimensional grid, because the exact frequency at which the spin-state is excited can be modulated by static (compared to the RF field) magnetic fields. To this end, a large static field (1-7 Tesla) and 2 auxiliary fields are used to determine at which point in the grid the resonance takes place. This, then, is done for each point in the grid. The result is a 3D proton (or water) density map of the brain (usually refered to as the "anatomy (map)" by people working in the field).

In functional MRI (fMRI), one takes the MRI process one step further by exploting the paramagnetic properties of oxygen; the amount of oxygen (in the blood, attached to hemoglobine) present in a certain area will modulate the proton spin resonance frequency as well, and this extra modulation can be measured. In this way, one can also make an oxygen-density map (one has to correct and compensate for a lot of things here, but that's a long story).

The oxygen density map can be used, because areas in the brain that are active "draw blood" towards themselves. This is called the BOLD (blood oxygen level dependent) response. Typically, this response lags one to a couple of seconds behind the actual activation of the brain area; in the fMRI data, one sees the signal in that area become higher. One can thus detect which areas of the brain are active.

The trick that the article describes is sometimes called brain state prediction, and that's a more difficult problem. Typically, one measures the fMRI signal while first supplying stimulus "1" N times, and them stimulus "2" N times. Determining which areas are active for stimulus "1" OR "2" (or both), usually has a reasonable SNR; based on the measured example, something simple like an F-test will suffice. However, given which part of the brain is active for either, the task of determining which of these active areas correspond more to simimulus "1" or "2", is more diffucult: usually the entire active area responds to both responses, and the difference is in the magnitude (or delay, or width) of the BOLD response in that area w.r.t. stimulus "1" or "2". These difference (sometimes expressed in a Contrast-to-Noise Ratio), is much smaller than the SNR for the activation. Consequently, this is an active research area.

To disspell some myths: the fMRI data can only be obtained using a HUGE scanner, and your head has to be completely inside. Furthermore, the sampling frequency is rather low (1.5 seconds between scans, usually), and the spatial resolution isn't that high either (64x64x64 voxels, in that order of magnitude).