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Families Hear from Completely Paralyzed Patients via New Device (singularityhub.com)
126 points by thomyorkie on Feb 18, 2017 | hide | past | favorite | 34 comments



It sounds like the novelty here is in the use of NIRS. A (very) similar approach was done in fMRI some years ago.

Paper cited by the present article: http://journals.plos.org/plosbiology/article?id=10.1371/jour...

Original fMRI paper: http://onlinelibrary.wiley.com.sci-hub.cc/doi/10.1002/ana.23...


I find it really fascinating that there's been problems using traditional brain-computer interfaces with these patients, and the researcher who developed this device specifically believes it's because once completely locked-in they actually experience a dramatic shift in the nature of their mental activity that prevents them from utilizing traditional BCI:

Niels Birbaumer, a neuroscientist at the Wyss Center for Bio and Neuroengineering in Geneva and coauthor of the new research, has an idea about why this may be, although there’s little evidence to support it so far. He proposed that it becomes harder over time for patients to channel their thoughts into voluntary action. “Anything you want, everything you wish does not occur. So what the brain learns is that intention has no sense anymore,” he says. “It is too difficult for them to switch from [a] more reflective state into an attentive state."

And that the device they used itself was designed to be more a passive monitoring of mental perception of input: The team stuck to simple questions that could be answered with a yes or no. “The answer in your head…occurs quickly and it occurs like a reflex. You don’t have to mobilize a lot of resources for such a simple answer,” Birbaumer says.

Earlier paper from Birbaumer: We propose that a lack of contingencies between goal directed thoughts and intentions may be at the heart of this problem. Experiments with chronically curarized rats support our hypothesis; operant conditioning and voluntary control of autonomic physiological functions turned out to be impossible in this preparation. In addition to assisted communication, BCIs consisting of operant learning of EEG slow cortical potentials and sensorimotor rhythm were demonstrated to be successful in drug resistant focal epilepsy and attention deficit disorder. First studies of non-invasive BCIs using sensorimotor rhythm of the EEG and MEG in restoration of paralysed hand movements in chronic stroke and single cases of high spinal cord lesions show some promise, but need extensive evaluation in well-controlled experiments. Invasive BMIs based on neuronal spike patterns, local field potentials or electrocorticogram may constitute the strategy of choice in severe cases of stroke and spinal cord paralysis. Future directions of BCI research should include the regulation of brain metabolism and blood flow and electrical and magnetic stimulation of the human brain (invasive and non-invasive). A series of studies using BOLD response regulation with functional magnetic resonance imaging (fMRI) and near infrared spectroscopy demonstrated a tight correlation between voluntary changes in brain metabolism and behaviour.

[1] http://www.popsci.com/new-brain-computer-interface-helps-com...

[2] http://journals.plos.org/plosbiology/article?id=10.1371/jour...

[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2151357/


So... in essence, people are so psychologically and behaviorally devastated, that they lose the ability to even formulate whole classes of thoughts? That sounds like they've been utterly broken as people.


"Thoughts" isn't quite what is being lost. Instead, you've still got the neurons that understand how goals relate to motor operations, and you've still got the motor neurons, but they've lost the neurotransmitter "protocol" (the calibrated receptivity-weights on the synapses connecting them) that allows them to communicate.

For me, an analogy to speech helps: a baby learning to speak must learn not just language in a high-level sense, but at a lower level, they must "learn" (i.e. calibrate neurotransmitter receptors attached to motor pathways) for how strongly each muscle in their vocal cords should respond to a given low-level phonemic motor-intent-signal from the brain.

If you didn't talk for years, those calibrations would drift, and although you'd remember what it was like to talk, you'd have to "learn to use" (i.e. calibrate) your vocal cords all over again.

The interesting thing here, is that this "calibration" (or lack thereof) continues to cascade through the entire graph of neurons: think backpropagation in machine learning. Motor-neurons that have nothing to talk to lose their ability to talk; and then the motor-intent-recognizing neurons find the only thing they had to talk to (the motor neurons) are now silent—as good as dead—and so they no longer get reward-trained and lose their receptivity-calibration—and on and on, back until you reach whatever subset of neurons is still doing things that achieve "rewards."


Is this essentially the idea of "muscle memory"?


Muscle memory is generally for referring to higher order things like blocking in a fight, swinging a bat, and other fast reactions that get better through practice instead of thought. Eg actions that your brain higher order plans but isn't thought by many to be consciously controlled. In fact when you think about a lot of these things consciously you mess up. Think throwing darts, shooting pool, etc.


More like they regain entirely new modes of thinking


Presumably this decay could be prevented if you started locked-in patients on BCI early in their predicament?


The feedback of BCI success is probably not enough to keep the neurons functional.


I dunno, the mere fact that it makes active thinking not be pointless is probably enough to keep them ticking over as people.


1. Why would patients locked-in for years be "generally happy"? Any theories?

2. Did the fMRI people (see top comment) respond similarly as happy?


1. Survival instinct? Perhaps man's search for meaning (Frankl) in the most dire situations? Realizing that being depressed about the situation will not help you and you make a conscious decision to accept the situation and be happy and find meaning within it's constraints. Perhaps because of the dominant western worldview people are inclined to view these locked in people who are the apex of the 'poor man' as being miserable and weak (See Andrei Plesu's article 'The Splendour and Misery of Humanism') http://www.fonselders.eu/wp-content/uploads/docs/I_am_a_Euro...


There's some research indicating that music can induce positive emotions in comatose patients. Maybe other stuff like having family visits , watching TV(?) Can do the same .

The main problems I thought they should have is isolation - but maybe one sided family/nurse visits is enough to deter that ?

And also no control - but this doesn't necessarily leads to depression if you learn to accept it, and if the environment is good.


I can foresee an application of this kind of technology along with VR being able to provide a rudimentary autonomy for these types of patients.



Remote control of a cyborg body via BCI and VR goggles. Wasn't that the plot of a movie that came out a few years back?


You may be thinking of Gamer, but Surrogates also matches up with this. Both pretty interesting movies.


Yes was talking about this yesterday at a party as I'm building one based on OpenBCI and Unreal, but I'm not sure about the latency


inb4 San Junipero


What's amazing to me is that these patients can see. They can't focus their cornea, because that would require muscle response. It's not even clear that they can blink so they would require eye drops to keep their eyes open.


Nitpick: The cornea is a fixed focal length, and it's a separate lens behind the cornea which flexes to 'accommodate' or focus the eye.


By the time you're 50, you can only focus your eyes by about 1 diopter anyway. Go try some 1 diopter reading glasses on; it's not a big difference. An uncontrolled eye ends up being quite mildly farsighted.


Wouldn't that mean the lens has a fixed focal length, so they'd only be able to see clearly objects at a particular distance?


They say they want to make improve it so patients can choose letters and spells stuff. But with with just a binary choice that can be done with 5 bits. Of course they will need more than that in order to increase accuracy.


A few years ago I was at a demonstration for an interface like this. It worked by measuring the effect of having an expectation fulfilled, i.e. the patient is shown a number of shapes in sequence, each representing a different choice, and when the one the patient wants appears, this can be inferred from an EEG.

IIRC, they used five different shapes and repeated each choice at least three times for error correction, and two or three choices selected one keyboard key. The poor grad student demonstrating the procedure made quite a few typos, after which he had to select backspace, and the process was excruciatingly slow anyway, so it took a few minutes until he managed to write "Hello, welcome to ...". But definitely better than nothing if you are locked in.


Black Mirror


I call bullshit.

The original paper is not bad as the article though, they call for replication for instance -

"In view of the gravity of the subject matter (i.e., establishing communication with nonverbal, completely paralyzed persons with preserved cognition), a call for replication of the current results by other investigators would be welcome. "


What I find interesting is this is a known scammy field.

HN is Reddit+

I wonder if there is a good opportunity for HN+ (Or is there already?)


>known scammy field

It really isn't, though. It's not a scam to publish with a p>.05 standard and get false positives. It just means you need to take studies with a grain of salt.

Note that this is a replication of a similar technique used in fMRI, but this time in a different modality (=> different signal space). [See Owen, 2012]. Unless you think the academic field of machine-learning is a "scam", then this is starting to look somewhat credible. It's getting interesting, let's say.


The system, a portable brain-machine interface, translates brain activity into simple yes or no answers to questions with around 70 percent accuracy.

Let's not forget that this means that (in the current version of the system) about every third answer output by the system is wrong.


They mention compensating by asking the same question many times.


“Anything you want, everything you wish does not occur. So what the brain learns is that intention has no sense anymore,”

That sounds like incredible hogwash. Why not admit you are doing the equivalent of connecting an oscilloscope to some random signal on a extremely complex high-speed board, and well, it's not that easy.


Because the same method works for people who aren't completely locked-in.


Should to reliveing to thousands paralyzed or with motor control difficulties.

Another similar field that can be even helpful to normal humans, is connecting the biological neural network to artificial one via nanobots. Immense benifits for increasing average human intelligence, education ...




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