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Lab-grown ‘mini-brains’ do mimic human brain development

69 points| chc2149 | 9 years ago |spectrumnews.org | reply

40 comments

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[+] hacker_9|9 years ago|reply
Title is an exaggeration, all they found was structures that looked similar to structures in our brains. They have no idea what these structures actually do, and even said there is huge amount of variability in the structures.

As an aside, this:

"They first froze the mini-brains and cut them into ultra-thin sections, which they mounted onto glass slides. They then labeled the sections with different combinations of colored fluorescent tags that are specific to certain cell types, and imaged the sections using an automated scanner."

Shows just how immature the neurobiology field is. I imagine that slicing, and then manually re connecting the slices in a 3d program, must be a pretty painstaking process. Not to mention you are left with no idea how data traveled round the structure. A code analogy would be having a huge codebase handed to you in little chunks, and you have to connect up the pieces by hand. And at the end of it, not even being able to debug it and see if things even work as expected.

[+] hsdistefa|9 years ago|reply
I worked in a lab where we had a similar problem reconstructing 3d images from manual sections via the same procedure.

Not only is it a painstaking process, but some slices are lost due to human error while sectioning and the tissue is mechanically distorted when placed onto the slides (squished between the glass and the cover slip).

The solution was simple, albeit much more expensive than sectioning: just MRI scan the organ.

[+] agumonkey|9 years ago|reply
Wondering if they ever tried to do input/output testing if that ever makes sense at the cerebral level of complexity.
[+] Florin_Andrei|9 years ago|reply
> Shows just how immature the neurobiology field is.

So then, what is your proposal for improvement?

[+] balabaster|9 years ago|reply
While I like this at a conceptual level, I'm struggling with it on a personal, perhaps moral level. A real brain, trapped, prisoner in a vat... if it's a real brain, it's going to have some level of sentience, just like the rest of us. Yet it is a slave. This is somewhat horrific to me. AI never really bothered me right up until I read this...
[+] derefr|9 years ago|reply
> if it's a real brain, it's going to have some level of sentience

Without a sensorimotor apparatus for the brain to manipulate and receive reward-signals from, and thus train to control, there is very likely no "thought" as we would consider it—nothing coherent, no train of thought, no high-level patterns. It's more like the sort of "thought" a foetus would have before its first moment of conscious awareness.

[+] QuantumGravy|9 years ago|reply
Unseen suffering is non-existent suffering. With no capacity for understanding what, if anything, another brain is experiencing, it's easy to rationalize and dismiss. That goes for fully formed humans as much as lab experiments.
[+] rflrob|9 years ago|reply
These brains are a lot smaller than a human brain---only about 2-5 mm across. While it's almost certainly a mistake to conflate size with complexity naively (songbirds are capable of pretty complex behaviors), I think it's much safer to assume that if human brains were capable of being much smaller while still allowing complex behaviors, they would be. Otherwise, we would probably gestate longer---compared to lots of other primates, humans are born "premature" in terms of developmental completeness.

Also, as other comments have pointed out, these organoids don't really have any neural inputs, so it's unlikely that they're wired in a way that is at all analogous to real human brains.

[+] namlem|9 years ago|reply
I mean, this is nothing compared to factory farmed chickens.
[+] hacker_9|9 years ago|reply
Sounds like something out of Doctor Who.
[+] idiot74|9 years ago|reply
How long until we can use these for machine learning?
[+] poslathian|9 years ago|reply
This is looking increasingly likely - here's a recent nature paper showing these organoids are electrically active, recording spikes from a dense 256ch electrode. That team also was able stimulate optogenetically yielding bidirectional communication with an organoid - http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...

Another interesting paper demonstrating that neural tissues can be effectively grown around mesh electrodes, providing both a scaffolding function as well a recording and stimulation functions. http://faculty.engr.utexas.edu/xie/xie/publications/ultrafle...

Neuroscience has been rapidly leveling up recently, its increasingly believable that high bandwidth bidirectional neural interfaces (at the cellular level) are on the horizon. DARPA was pitching this a few years ago (NESD) and it was pretty far out, but now see Kernel and Neuralink and the 10 or so companies partnered in to those efforts mostly-successfully developing all kinds of technologies required by this roadmap (disclosure: including my own).

[+] Robotbeat|9 years ago|reply
After Elon Musk's Neuralink figures out a scalable way to interface with neurons. Need probably millions of electrodes, not just a few hundred like we use today.

It would be kind of crazy if we develop full AI by literally using brains in vats. But it makes sense (even if it is horrifying). Meat is cheap, and the brain is like an exa-OPS computer running on 20 Watts of power. If you could solve the interface problem and figure out how to actually use it practically, brain is like 6 or 7 orders of magnitude cheaper than the next-cheapest computing substrate. That's like half a century of Moore's Law (and Moore's Law is basically over now... much slower pace, at least).

(Here's an example using rat neurons: https://singularityhub.com/2010/10/06/videos-of-robot-contro... And this one: https://www.newscientist.com/article/dn6573-brain-cells-in-a... )

[+] milesvp|9 years ago|reply
Some years ago (9+) Professor DeMarse published some papers on training petri dish brains cells how to "fly a plane" (or more appropriately "keep a simulated plane from crashing"). I have a copy of the paper at home, but can't think of the title, (it was kind of hard to find a copy since it wasn't publicly available online). You might look at what his lab is currently working on though.

http://neural.bme.ufl.edu/

[+] luminiferous|9 years ago|reply
Is that even "machine" learning anymore?