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I've recently completed a masters thesis on EEG based mind reading, and I think I have a fairly good grasp on the state of the art in this field. I also have a

by lars 15y ago

I've recently completed a masters thesis on EEG based mind reading, and I think I have a fairly good grasp on the state of the art in this field. I also have a copy of Kurzweil's The Singularity is Near by my bed, and I'm usually strongly optimistic about technology. But if IBM are talking about EEG based technology here, I would have to bet that they are flat out wrong on this one. I'll explain why. Something like moving a cursor around by thinking about it, or thinking about making a call and having it happened requires a hell of a lot of bits of information to be produced by the brain computer interface. With the current state of the art we can distinguish between something like 2-6 classes of thoughts sort-of reliably, and even then it's typically about thinking of particular movements, not "call mom". Importantly, what most people look for in the signal (the feature in machine learning terms) are changes in signal variance. And there are methods to detect these changes that are in some sense mathematically optimal (which is to say they can be still be improved a little bit, but there won't be any revolutionary new discoveries.) There may be other features to look for, but we wont be getting much better at detecting changes in signal variance. Some methods can report results like a 94% accuracy over a binary classification problem. Such a result may seem "close to perfect", but it is averaged over several subjects, and likely varies between for example 100% and 70%. For the people with 70% accuracy, the distinguishing features of their signals are hidden for various reasons. And this is for getting one bit of information out of the device. Seems like such a device would need to work for everyone to be commercially successful. In computer vision we have our own brains to prove that the problems can be solved. For EEG based brain computer interfaces, such proofs don't exist. There are certain things you probably can't detect from an EEG signal, meaning the distinguishing information probably isn't there at all. I'm easily willing to bet IBM money that who I would like to call can not be inferred from the electrical activity on my scalp. (Seriously IBM, let's go on longbets.org and do this.)

Steko 15y ago
"who I would like to call can not be inferred from the electrical activity on my scalp" If I read the blog post correctly the claim is not passive mind reading. The claim is that the user has some training to issue the sorts of thought commands that can be reliably picked up. If I think "call mom" it doesn't do anything. But if I think "Up Up Down Down Left Right Left Right" maybe it can interpret that correctly as my preassigned shorthand for "call mom".
- pfraze 15y ago
  I bet it's harder not to compulsively think "Up Up Down Down Left Right Left Right" than it is to dial a phone.
  - MrMatters 15y ago
    Maybe if it recognized just thinking about that sequence, but I think having to deliberately focus on each direction (kind of like pressing a series of buttons in your mind, one after the other) would be too hard to accidentally do like that.
- lars 15y ago
  They're a little fuzzy, but the exact quote from the video is: "IBM scientists are researching how to link your devices, such as a computer or a smart phone. So you just need to think about calling someone, and it happens." From the context it is implied that this will happen in 5 years. In their in-depth blog post about the topic, they say: "...I could wonder what the traffic will be like on the way home and this information would pop up in front of me." So I think they are actually describing a "call mom" scenario, and I strongly doubt that the information to detect that is at all present in an EEG signal.
kevinalexbrown 15y ago
> I'm easily willing to bet IBM money that who I would like to call can not be inferred from the electrical activity on my scalp. (Seriously IBM, let's go on longbets.org and do this.) Be more precise. If you can distinguish two classes, you can convey anything through EEG, however slowly (think 'bits'). With error, use error-correcting codes and you can get relatively high accuracy. Pedantics aside, I agree in sentiment. Even with invasive techniques we can only roughly decode movement.
- lars 15y ago
  Sure. Let's say a five second EEG segment, recorded from up to 200 electrodes. I bet that by 2017 we cannot accurately detect who a person would like to call out of phonebook of 50 people. Specifically, in a setting where each person is as likely to be called (equal prior probability), I bet the detection accuracy will not exceed 4% on average with a phone book of 50 people. I'm talking about the BCI understanding a "call mom" thought, not detecting it through some other means like a movement (though I don't expect that to work by then either).
  - grannyg00se 15y ago
    Why would "call mom" be more difficult than "Left left up up"? I'm guessing left, right, up, down, would map to certain EEG patterns. Why would it be more difficult to map call and mom to their patterns? It seems to me that if you can map patterns for four directions, you should also be able to map patterns for 50 different phone book entries and several verbs.
    - lars 15y ago
      I'm not being clear, I don't think that thinking the words "left left up up" would be detectable through EEG. When I say detecting movement, I mean things like imagining moving a hand, a foot or a tongue. These movements use distinct areas of the brain so you can distinguish between them by looking at where on the scalp the change occurred. This is done in ways that are known to be close to perfect. However, you probably couldn't use scalp location if you wanted to distinguish "call mom" from "call John", as they would presumably activate the same area of the brain. There are of course other things one could look at, and I obviously can't prove that it can't be done. But at the same time I have never seen any kind of positive result for an EEG classification task at this level of detail.
tokenadult 15y ago
Thanks for the interesting detailed information about EEG resolution, which I can attest is in accordance with what I have read about neuroelectrical interaction in other contexts. But what is to me implausible about thinking "phone Mom" and having my computer do it for me is that this scenario envisions an unusually high degree of usability that no consumer-facing software writers have ever achieved. Right now, on a BRAND NEW computer system using mostly application programs recommended by Hacker News readers (for example, I am using Chrome to Web browse), I can't count on my computer doing what I want even if I have my hands on the keyboard or a hand on my mouse. User-interface design appears to be HARD--or at least, it is rarely done right--so I am very doubtful that in five years or even twenty-five years I'll be able to use a computer that really does what I think.
- swombat 15y ago
  Hate to be that guy, but Siri is getting pretty close to this.. "Phone Mom" will work with an iPhone 4S.
- imgabe 15y ago
  Given the above comment I would be even less optimistic about a computer being able to determine the difference between thinking "I should call mom at some point" or "What a nice phone call I had with mom yesterday" and "call mom right now". This would take the "butt-dialing" phenomenon to disturbing new levels.
nishantmodak 15y ago
Could not agree more! If you go and look back http://www.ibm.com/smarterplanet/us/en/ibm_predictions_for_future/examples/index.html http://www.ibm.com/smarterplanet/us/en/ibm_predictions_for_f... IBM has predicted these since 2006. And in 2006 - they said Our mobile phones will start to read our minds .. so you know what to make of this one!
patrickk 15y ago
James May (of BBC's Top Gear) trying to control a wheelchair with his mind: http://www.youtube.com/watch?v=Uyrd0uOuyms http://www.youtube.com/watch?v=Uyrd0uOuyms Even giving directions via thought is tricky.
zerostar07 15y ago
Even with very invasive techniques (chronic implants), the reading of motion signals for example is very problematic. One of the first devices to do that is the http://en.wikipedia.org/wiki/BrainGate http://en.wikipedia.org/wiki/BrainGate . It requires substantial training and retraining because of brain plasticity. Still, these are major breakthroughs, and hopefully we will be able to find a reliable and usable signal, but i agree, EEG is too bulky for that purpose.

by lars 15y ago

Steko 15y ago

"who I would like to call can not be inferred from the electrical activity on my scalp" If I read the blog post correctly the claim is not passive mind reading. The claim is that the user has some training to issue the sorts of thought commands that can be reliably picked up. If I think "call mom" it doesn't do anything. But if I think "Up Up Down Down Left Right Left Right" maybe it can interpret that correctly as my preassigned shorthand for "call mom".

pfraze 15y ago
I bet it's harder not to compulsively think "Up Up Down Down Left Right Left Right" than it is to dial a phone.
- MrMatters 15y ago
  Maybe if it recognized just thinking about that sequence, but I think having to deliberately focus on each direction (kind of like pressing a series of buttons in your mind, one after the other) would be too hard to accidentally do like that.
lars 15y ago
They're a little fuzzy, but the exact quote from the video is: "IBM scientists are researching how to link your devices, such as a computer or a smart phone. So you just need to think about calling someone, and it happens." From the context it is implied that this will happen in 5 years. In their in-depth blog post about the topic, they say: "...I could wonder what the traffic will be like on the way home and this information would pop up in front of me." So I think they are actually describing a "call mom" scenario, and I strongly doubt that the information to detect that is at all present in an EEG signal.

kevinalexbrown 15y ago

> I'm easily willing to bet IBM money that who I would like to call can not be inferred from the electrical activity on my scalp. (Seriously IBM, let's go on longbets.org and do this.) Be more precise. If you can distinguish two classes, you can convey anything through EEG, however slowly (think 'bits'). With error, use error-correcting codes and you can get relatively high accuracy. Pedantics aside, I agree in sentiment. Even with invasive techniques we can only roughly decode movement.

lars 15y ago
Sure. Let's say a five second EEG segment, recorded from up to 200 electrodes. I bet that by 2017 we cannot accurately detect who a person would like to call out of phonebook of 50 people. Specifically, in a setting where each person is as likely to be called (equal prior probability), I bet the detection accuracy will not exceed 4% on average with a phone book of 50 people. I'm talking about the BCI understanding a "call mom" thought, not detecting it through some other means like a movement (though I don't expect that to work by then either).
- grannyg00se 15y ago
  Why would "call mom" be more difficult than "Left left up up"? I'm guessing left, right, up, down, would map to certain EEG patterns. Why would it be more difficult to map call and mom to their patterns? It seems to me that if you can map patterns for four directions, you should also be able to map patterns for 50 different phone book entries and several verbs.
  - lars 15y ago
    I'm not being clear, I don't think that thinking the words "left left up up" would be detectable through EEG. When I say detecting movement, I mean things like imagining moving a hand, a foot or a tongue. These movements use distinct areas of the brain so you can distinguish between them by looking at where on the scalp the change occurred. This is done in ways that are known to be close to perfect. However, you probably couldn't use scalp location if you wanted to distinguish "call mom" from "call John", as they would presumably activate the same area of the brain. There are of course other things one could look at, and I obviously can't prove that it can't be done. But at the same time I have never seen any kind of positive result for an EEG classification task at this level of detail.

tokenadult 15y ago

Thanks for the interesting detailed information about EEG resolution, which I can attest is in accordance with what I have read about neuroelectrical interaction in other contexts. But what is to me implausible about thinking "phone Mom" and having my computer do it for me is that this scenario envisions an unusually high degree of usability that no consumer-facing software writers have ever achieved. Right now, on a BRAND NEW computer system using mostly application programs recommended by Hacker News readers (for example, I am using Chrome to Web browse), I can't count on my computer doing what I want even if I have my hands on the keyboard or a hand on my mouse. User-interface design appears to be HARD--or at least, it is rarely done right--so I am very doubtful that in five years or even twenty-five years I'll be able to use a computer that really does what I think.

swombat 15y ago
Hate to be that guy, but Siri is getting pretty close to this.. "Phone Mom" will work with an iPhone 4S.
imgabe 15y ago
Given the above comment I would be even less optimistic about a computer being able to determine the difference between thinking "I should call mom at some point" or "What a nice phone call I had with mom yesterday" and "call mom right now". This would take the "butt-dialing" phenomenon to disturbing new levels.

nishantmodak 15y ago

Could not agree more! If you go and look back http://www.ibm.com/smarterplanet/us/en/ibm_predictions_for_future/examples/index.html http://www.ibm.com/smarterplanet/us/en/ibm_predictions_for_f... IBM has predicted these since 2006. And in 2006 - they said Our mobile phones will start to read our minds .. so you know what to make of this one!

patrickk 15y ago

James May (of BBC's Top Gear) trying to control a wheelchair with his mind: http://www.youtube.com/watch?v=Uyrd0uOuyms http://www.youtube.com/watch?v=Uyrd0uOuyms Even giving directions via thought is tricky.

zerostar07 15y ago

Even with very invasive techniques (chronic implants), the reading of motion signals for example is very problematic. One of the first devices to do that is the http://en.wikipedia.org/wiki/BrainGate http://en.wikipedia.org/wiki/BrainGate . It requires substantial training and retraining because of brain plasticity. Still, these are major breakthroughs, and hopefully we will be able to find a reliable and usable signal, but i agree, EEG is too bulky for that purpose.