[HN Gopher] A soft, wearable brain-machine interface
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A soft, wearable brain-machine interface
Author : sizzle
Score : 87 points
Date : 2021-09-07 17:59 UTC (5 hours ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| 0xFACEFEED wrote:
| Could someone explain to a dummy like me: what are the actual
| technological bottlenecks for brain-machine interfaces?
|
| Like... setting aside all the things that, given enough
| time/effort, we'll reach some useful maximum. I'm told that with
| ML (eg: image classification) we'll eventually train the systems
| enough that they'll do a pretty amazing job.
|
| So is it converting analog brain signals to digital? Is the rate
| of data transmission even relevant here? What would happen if we
| had enough "brain data" from a single person to saturate a 10
| gigabit network? Do we have the software to do anything
| meaningful with that?
| uuidgen wrote:
| The brain is more like a CPU implemented in FPGA than a CPU
| synthesised into silicon.
|
| Signals are only somewhat local - you get increased activity in
| this or that region and can correlate it with what happens in
| the brain - like power analysis attacks on crypto chips - the
| algorithm has to recover the data from the limited, noisy
| signal we are able to pickup.
|
| You can't just put electrode in every single neuron to read its
| state like you can't put an electrode into every single piece
| of conductive metal on a chip - it would be to tight to fit and
| everything would stop working.
| dr_dshiv wrote:
| So many challenges. One is that we can only receive information
| from certain parts of the brain--those where the neurons are
| perpendicular to the scalp. As you know, the brain is really
| convoluted, so this makes for a very messy signal. Another
| issue is that the raw noise makes it extremely difficult to
| detect faint signals.
|
| An approach for this is training models that have expectations
| based on the stimuli themselves; e.g., to find neural resonance
| with different frequencies in the stimulus.
| didntknowya wrote:
| the main problem is not software, AI, etc. It's that we can't
| get the data reliably- i.e. current sensors are not sensitive
| enough to pick up brainwaves/activity (esp with interference
| from muscle etc). The gold standard is electrodes implanted in
| a brain but is a bit invasive as an interface.
| devindotcom wrote:
| Right now the state of the art options are either surgically
| implanted electrode arrays (invasive and very limited in what
| they can detect), electroencephalogram type helmets (non-
| invasive but only get very vague signals), or fMRI type imaging
| (more precise but still only gross detail, and requires an
| enormous complex machine).
|
| There's no obvious way forward with any of these that produces
| what you or I might consider a true brain machine interface. We
| don't have the tech AND we don't understand the brain enough.
|
| Fortunately you don't need a brain-reading device to produce
| something useful, just like you don't need a teraflop computer
| to go to the moon. I've written recently about an EEG helmet
| that can be used by profoundly disabled folks to navigate a UI,
| type, and so on, and that doesn't require a precise signal at
| all. So I think what you'll find is while the Musks of the
| world are chasing a sci-fi dream of what they think the
| technology ought to be, most of the utility will come out of
| using what it's actually capable of in a smart and
| compassionate way.
| judge2020 wrote:
| > What would happen if we had enough "brain data" from a single
| person to saturate a 10g network?
|
| Upgrade to USB 4 :)
| 0xFACEFEED wrote:
| Derp. Corrected to 10 gigabit.
| pama wrote:
| Our brain was not built to directly transmit signals nor to
| accept input wires to read / write signals. I am sure one or
| the other can eventually be overcome safely. But we are not
| there yet.
| ebb_earl_co wrote:
| Like all of WaitButWhy's articles, I think this one [0] helps a
| person understand from the fundamentals. I linked to part 3
| which is the section for Brain-Machine Interfaces in
| particular, but it behooves you to read from the beginning
|
| [0] https://waitbutwhy.com/2017/04/neuralink.html#part3
| tbenst wrote:
| The big challenge for non-invasive BCI is that most interesting
| information content in the brain (e.g. speech) is encoded in
| high frequency firing activity, and the skull acts as a low-
| pass filter.
| seph-reed wrote:
| Do you ever feel the impulse to "ctrl-f" when you're at the
| grocery store?
|
| Imagine the feeling of going to reach for something, and
| accidentally just envisioning moving your arm. Might be like
| "stepping into air" when you're almost asleep.
| [deleted]
| 58x14 wrote:
| When I used to regularly play a particular lane-based MOBA, any
| time I'd need to react quickly while driving, I'd instinctively
| feel the need to burst some variation of QWE depending on which
| character I'd recently been playing.
|
| Sometimes if I practice difficult scales (those with novel
| movements for weak fingers e.g. left pinky and ring) on the
| piano before typing on a keyboard, I'll mistype more
| frequently.
|
| I wonder if this type and similar phenomena is also related:
| https://en.wikipedia.org/wiki/Phantom_vibration_syndrome
| hemloc_io wrote:
| I've had this happen when opening a cookbook. Spooky for sure.
|
| Time to go outside for a bit.
| [deleted]
| yhvh wrote:
| https://www.cumulusneuro.com/
| fouc wrote:
| It's striking the site is focusing on the use of it in clinical
| trials only, and not for general purpose use yet unfortunately.
| judge2020 wrote:
| Probably requires:
|
| - proven usefulness for general computer tasks
|
| - must be relatively easy and quick to set up
|
| - cost must be reasonable, if expensive - anything over
| something like $2,000 is going to severely limit your
| customer pool. A semi-automated manufacturing line will help
| with this
|
| - for good measure, a crack marketing team
|
| Another consideration is that the BCI industry is moving
| insanely fast. By the time you set up a production line and
| start mass-producing, there might be news about a novel much-
| better process that overshadows your product and destroys
| sales. This is effectively what happened with VR in 2012-2018
| when everything was super expensive; only as of recent can
| you recommend an Index or Quest 2 to people without fearing a
| huge leap in VR quality to be coming in the near future.
| anfractuosity wrote:
| It looks like they're using one 10x10 array of electrodes?
|
| With say the traditional EEG electrodes, they seem to cover all
| over the head (some with say around 128 electrodes).
|
| I understand that they'd get a higher quality signal, but is the
| fact they're only using electrodes over one area of the scalp a
| disadvantage?
| 58x14 wrote:
| I have a Muse 2 [1] and a Flowtime [2]; both are consumer-
| oriented portable EEGs using Bluetooth to transmit data displayed
| on their respective mobile apps.
|
| The Muse hardware is seriously inhibited by the same user-
| exploitative trends we see everywhere, accompanied by meaningless
| promises. Many researchers used the Muse SDK and API until they
| discontinued it in 2019 [3] in favor of Muse Direct - another way
| to force users to feed Muse their data and lock them into a
| subscription.
|
| Unsurprisingly, this was also abandoned [4] and they claim "We're
| working on a solution that allows you to collect raw EEG data
| using the free to download" app, which would still allow Muse
| complete control over your authentication, use and data. Ugh.
|
| At least the community has reverse-engineered the LSL protocol
| and built a Python package [5].
|
| Flowtime claimed that it offers a closed API, as they don't have
| the resources to maintain an open API [6]. I remember somewhere
| they claimed it was on their roadmap, but I searched again today
| and couldn't find any support of their claim.
|
| BrainBit [7] and NextMind [8] seem to provide more robust
| developer tools, although I have no experience. Naturally, each
| of these runs more than double the ~$200 cost of the Muse and
| Flowtime devices.
|
| I have no formal neurological education but I strongly believe
| non-invasive EEGs, combined with novel, gamified training
| techniques coupled with machine learning will usher in a new era
| of digital interactions. Like the transition from tactile
| smartphone keypads to the eventually-ubiquitous full touchscreen,
| I expect many design iterations in both hardware and software
| will produce utterly fascinating products.
|
| I can't wait to get excited again for a product launch.
|
| [1] https://choosemuse.com/muse-2/ [2]
| https://www.indiegogo.com/projects/flowtime-biosensing-medit...
| [3] https://github.com/sccn/labstreaminglayer/issues/30 [4]
| https://choosemuse.force.com/s/article/Muse-Direct-Subscript...
| [5] https://github.com/alexandrebarachant/muse-lsl [6]
| https://www.kickstarter.com/projects/987756376/flowtime-bios...
| [7] https://sdk.brainbit.com/ [8] https://www.next-
| mind.com/developer/
| refulgentis wrote:
| I've been kicking around getting one of these for years, the
| deciding factor for me is essentially "what kind of demos can
| you pull off with these?"
|
| ex. a simple "yes / no" detector would be meh, pointer control
| would be amazing, some sort of mood detector/brain trainer type
| apps would be _awesome_ since it'd be producing value for me
| Mizza wrote:
| Curious about these "micro-needle electrodes". If I try on my
| buddy's helmet, is there a chance I'm going to catch hepatitis?
| kortex wrote:
| I would guess they are meant as consumables. The needles are
| 0.8 mm long and 0.35 mm wide, pyrimidal spikes. Definitely too
| shallow to cause bleeding but that's still quite intimate
| contact.
| stcredzero wrote:
| I'm also concerned about how such devices will affect and be
| affected by cavitation. Cavitation inside the skull has been
| found to happen in concussion injuries in explosions. It's also
| thought that it can happen with the smaller impulses coming
| from punches and everyday impacts. Are the devices subject to
| cavitation, particularly the long, thin parts, and what happens
| to those long thin parts inside the brain when they are
| subjected to cavitation?
|
| EDIT: This device is only penetrating the scalp, but other
| devices like Neuralink penetrate into the brain.
| kortex wrote:
| It's barely even penetrating the scalp. The needles (really
| better described as spikes, they have a fair amount of draft,
| about 20deg) only puncture the strateum corneum - outer layer
| of dead skin cells and lipids.
| mattkrause wrote:
| This particular device doesn't even penetrate al the way
| through the scalp, so the skull would likely obliterate these
| long before they reach the brain.
|
| Motion is a problem for things that are inserted into the
| brain, but people have been getting DBS and sEEG implants for
| 30 years, and it's manageable, though not totally solved.
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(page generated 2021-09-07 23:00 UTC)