Shawn Mikula on Brain Preservation Protocols and Extensions

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Recently published article in Nature Methods on a new protocol for preserving mouse brains that allows the neurons to be traced across the entire brain, something that wasn't possible before. This is exciting because in as little as 3 years, the method could be extended to larger mammals (like humans), and pave the way for better neuroscience or even brain uploads. From the abstract:

Here we describe a preparation, BROPA (brain-wide reduced-osmium staining with pyrogallol-mediated amplification), that results in the preservation and staining of ultrastructural details throughout the brain at a resolution necessary for tracing neuronal processes and identifying synaptic contacts between them. Using serial block-face electron microscopy (SBEM), we tested human annotator ability to follow neural ‘wires’ reliably and over long distances as well as the ability to detect synaptic contacts. Our results suggest that the BROPA method can produce a preparation suitable for the reconstruction of neural circuits spanning an entire mouse brain

http://blog.brainpreservation.org/2015/04/27/shawn-mikula-on-brain-preservation-protocols/

Here we describe a preparation, BROPA (brain-wide reduced-osmium staining with pyrogallol-mediated amplification), that results in the preservation and staining of ultrastructural details throughout the brain at a resolution necessary for tracing neuronal processes and identifying synaptic contacts between them. Using serial block-face electron microscopy (SBEM), we tested human annotator ability to follow neural ‘wires’ reliably and over long distances as well as the ability to detect synaptic contacts. Our results suggest that the BROPA method can produce a preparation suitable for the reconstruction of neural circuits spanning an entire mouse brain

http://blog.brainpreservation.org/2015/04/27/shawn-mikula-on-brain-preservation-protocols/

That is very interesting; there does seem to be quite rapid progress in this area.

From the blog entry:

... the reason for this is because simulating the neural activity on a Von Neumann (or related computer) architecture does not reproduce the causal structure of neural interactions in wetware. Using a different computer architecture may avert this problem ...

Can anyone explain what that means ? I can't see how it can be correct.

Shawn Mikula here. Allow me to clear up the confusion that appears to have been caused by being quoted out of context. I clearly state in the part of my answer preceding the quoted text the following:

"2) assuming you can run accurate simulations of the mind based on these structural maps, are they conscious?".

So this is not a question of misunderstanding universal computation and whether a computer simulation can mimic, for practical purposes, the computations of the brain. I am already assuming the computer simulation is mimicking the brain's... (read more)

10jacob_cannell11y

Well, the simplest explanation may be: it's not correct. He doesn't believe in functionalism (or at least he probably doesn't): [...] Perhaps he doesn't really understand the implications of universal computability. I've found that as a rule of thumb, almost everyone with a background in computer science believes in functionalism, as do most physicists, but it's somewhat less common for those with a bio science related background. Someone can be an expert in the details of neurochemistry without having the slightest clue how artificial consciousness would actually work in practice.

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Shawn Mikula on Brain Preservation Protocols and Extensions

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Shawn Mikula on Brain Preservation Protocols and Extensions

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