Fulltext: https://www.dropbox.com/s/2mmdmty3nxfe5u8/2015-louveau.pdf / http://sci-hub.org/downloads/e18c/louveau2015.pdf
there quite a lot we still don't know about the brain and uploading might be harder than previously believed.
It's worth remembering the functions of the lymphatic system, and that important discoveries tend to be made first.
After reading the paper, NeuroscientistNews, HN & Reddit comments, it sounds as if for the most part the new tube wouldn't be directly affecting the brain as the flow is brain->lymph-tube, unless something has gone wrong, possibly being a new cause of various mental disorders as the flow reverses and causes problems.
So it sounds as if an upload which ignored the new tube would work just fine as a normal healthy human mind - in the worst (best?) case, the uploads might not be able to reproduce observed rates of schizophrenia or autism.
I remember reading a book many years ago which talked about the "hormonal bath" in the body being actually part of cognition, such that thinking of the brain/CNS as the functional unit is wrong (it's necessary but not sufficient).
This ties in with the philosophical position of Externalism (I'm very much into the Process Externalism of Riccardo Manzotti). The "thinking unit" is really the whole body - and actually finally the whole world (not in the Panpsychist sense, quite, but rather in the sense of any individual instance of cognition being the peak of a pyramid that has roots that go all the way through the whole).
I'm as intrigued and hopeful about the possibility of uploading, etc., as the next nerd, but this sort of stuff has always led me to be cautious about the prospects of it.
There may also a lot more to be discovered about the brain and body too, in the area of some connection between the fascia and the immune system (cf. the anecdotal connection between things like yoga and "internal" martial arts and health).
I'm really skeptical of claims like « the "thinking unit" is really the whole body », they tend to discard quantitative considerations for purely qualitative ones.
Yes, the brain is influenced, and influences, the whole body. But that doesn't mean the whole body has the same importance in the thinking. The brain is also influenced by lots of external factors (such as ambient light or sounds, ...) if as soon as there is a "connection" between two parts you say "it's the whole system that does the processing", you'll just end up considering the solar system as a whole, or even the entire event horizon sphere.
There is countless evidence that, while your body and your environment have significant influence on your thinking, it's just influence, not fundamentally being part of the cognition. For example, people who have graft or amputations rarely change personality, memory or cognitive abilities in any way comparable to what brain damage can do.
There may also a lot more to be discovered about the brain and body too, in the area of some connection between the fascia and the immune system (cf. the anecdotal connection between things like yoga and "internal" martial arts and health)
We have more than anecdotal evidence. While there still things to be discovered about the interaction between fascia and the immune system, it's already quite clear that if fascia get's too loose and cells rub against each other too much they die and you get inflammation.
Macrophage also have it harder to get around when tissue is very tight.
The fact that we still get surprised by new elements of the brain suggests that there quite a lot we still don't know about the brain
Indeed, and more big surprises are bound to surface.
and uploading might be harder than previously believed
I'm sure uploading will be hard, but the discovery you mention (which looks like some extra plumbing infrastructure for the wetware at this point) does not seem to fight the idea that the cognitive processes can be abstracted and extracted from the wetware.
As far as I know there isn't any direct reason why this would make uploading harder; it's a non-computational element. But the fact that it took so long to discover it does mean we should expect to have missed more things.
I saw a fun talk at a conference in December where Jeff Lichtman showed us some of his processed data from his 5x5x30 nanometer resolution mouse brain tissue electron microscope scans (of which probably a 30 micron wide cylinder was actually properly annotated). He mentioned that only 40% of the things-that-were-clearly-synapses in the annotated dataset were the large spine-based synapses that have been well studied, and that there were a couple cells in there that he had no idea what they were at all.
(sings)
The lymph node is connected to the... central nervous system! The central nervous system is connected to the... brain lobes! The brain lobes are connected to the... Descartian ghost! Doing the consciousness dance!
Just a frivolous comment, but I'm reminded of this classic SF story.
BTW, the "Robert von Engen" in the story is clearly John von Neumann, Engen's book “Logical Control: The Computer vs. Brain” is Neumann's “The Computer and the Brain”, and Engen's paper “Memory Registers: Stimulation Criteria” takes its title from two sections of Neumann's book. I don't know how many other real-world correspondences there are. In the real world, unlike the story, Neumann's book was published posthumously.
Kipnis et al found a new part of the lymphatic system. It goes into the brain.
The fact that we still get surprised by new elements of the brain suggests that there quite a lot we still don't know about the brain and uploading might be harder than previously believed.
Given that these vessels were hard to find, it will be interesting to see whether other hard to find vessels will be discovered in the coming years.
Besides their Nature article Structural and functional features of central nervous system lymphatic vessels, there a good article on NeuroscientistNews titled Missing link found between brain, immune system -- with major disease implications.