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aurellem

Re:Nectome MVP on Tuesday May 10, 2022 @06:50PM (#31333688)
We had a few approaches, happy to discuss directly if you email info [at] nectome [dot] com.
Re:Improving Connectomics by an Order of Magnitude on Monday July 16, 2018 @03:05PM (#17544008)
Yes, this is an important advance in the field. Google's been working on this for the past few years after convincing Viren Jain (https://www.janelia.org/our-research/former-labs/jain-lab) to leave Janelia and perfect this technology. Very cool stuff! Even as early as two years ago, it generally took a grad student months to years of work to manually reconstruct 50-100 neurons (see https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4844839/); now this same process can be done in virtually no time at all. Expect to see several more papers in the future involving reconstructions of thousands to tens of thousands of neurons, instead of the hundreds we've been seeing. Exciting times!
First off, again we are currently conducting research and are not preserving people.

Our early supporters have shown their support for Nectome’s research through fully refundable deposits, and we hope that they will live long, healthy lives, creating the very memories that they hope can one day be preserved.

We’re proud of the progress we’ve made so far—demonstrating that the ultrastructure (connectome) is preserved. The connectome is a necessary starting point upon which models of the brain can be built [0]. We intend to continue researching and validating preservation of important biomolecules as we explore the efficacy limits of ASC. We intend to develop these tools on a timeline to allow proper feedback from the neuroscience community. I certainly don’t want our marketing to imply that we have near-term or even specific plans to offer anything commercially for clinical use, so I will read through our website again and try to find areas where one can get the wrong idea.

[0] From https://www.scientificamerican.com/article/c-elegans-connect...: “Some people say we don't know anything about how C. elegans's brain works and I am like, 'Yes, we do!'" says Cornelia Bargmann of The Rockefeller University, who has studied the nematode for more than two decades and attended the Columbia debate. "A lot of what we know about C elegans's rapid behaviors we have learned through and with the connectome. Every time we do an experiment, we look at those wiring diagrams and use them as a starting point for generating hypotheses."

> If you look at the pictures it can barely capture the synapses

Electron micrographs vary quite a bit in quality (good micrographs are an art), but if you can barely see the synapses, you may be thinking of light microscopy, where it’s very difficult to see differences in the sizes of synapses. You can see for yourself what synaptic details electron microscopy allows you to see in the book, "Fine Structure of the Nervous System: Neurons and Their Supporting Cells". You might also want to see the FIB-SEM images from the Brain Preservation Foundation at https://www.youtube.com/watch?v=RYKIePuVENY, which I find quite beautiful.

As for how sizes may relate to weights [1]: “Some axons form two or more synapses with the same dendrite, but on different dendritic spines. These synapses should be the same strength because they will have experienced the same history of neural activity…the synaptic areas and volumes of the spine heads were nearly identical. This remarkable similarity can be used to estimate the number of bits of information that a single synapse can store, since the size of dendritic spines and their synapses can be used as proxies for synaptic strength.”

I hope that these are informative. I do want to clarify that we are not arguing that electron micrographs of brain tissue are all that’s needed to reconstruct memories. We are interested in building the best brain preservation technology possible, and one of the ways we evaluate brain preservation is with electron microscopy. The connectome is the first step, the “skeleton” upon which models of the mind can be built.

[1] "Nanoconnectomic upper bound on the variability of synaptic plasticity" at https://elifesciences.org/articles/10778

The process is described in the science paper at https://www.sciencedirect.com/science/article/pii/S001122401..., and also at the Brain Preservation Foundation website (http://www.brainpreservation.org/). It involves fixation with glutaraldehyde and then vitrifixation for long-term storage. It does not use plastic.
Nectome is still in the research stage, so we are not preserving anyone. If you'd like to learn more about how the preservation process works, check out the paper at https://www.sciencedirect.com/science/article/pii/S001122401... or the summary at http://aurellem.org/ASC/html/ASC-introduction.html.

And yes, we are in YC Winter 18

It's important to understand first of all that Nectome is not currently preserving brains in a clinical setting. We are still very firmly in the research phase of building a brain banking technique sufficiently powerful to preserve memories. (see https://nectome.com for more details). However, I envision that a validated preservation technique would preserve the entire body, including the peripheral nervous system.
If you want to get into some of the literature around mind uploading, I'd start with some of Daniel Dennett's work such as "Consciousness Explained". If you think that it's possible for a computer program to have its own sense of self, then it's interesting to think about what it would feel like for that program to be stopped, copied to a new computer, and then started again. There's definitely a lot of literature and debate around these issues!