I'm knee-deep in reading a NYTImes Mag article about Sebastian Seung, a Princeton neuroscientist who hopes to map the connections among neurons in the human brain. The human connectome, as it's called, has recently been elevated to Holy Grail status within neuroscientist. While I doubt that it deserves that status, sure, why not map all the connections and see what you get?
In the process Seung has developed a game that allows citizens – that's you and me – to help:
In 2012, Seung started EyeWire, an online game that challenges the public to trace neuronal wiring — now using computers, not pens — in the retina of a mouse’s eye. Seung’s artificial-intelligence algorithms process the raw images, then players earn points as they mark, paint-by-numbers style, the branches of a neuron through a three-dimensional cube. The game has attracted 165,000 players in 164 countries. In effect, Seung is employing artificial intelligence as a force multiplier for a global, all-volunteer army that has included Lorinda, a Missouri grandmother who also paints watercolors, and Iliyan (a.k.a. @crazyman4865), a high-school student in Bulgaria who once played for nearly 24 hours straight. Computers do what they can and then leave the rest to what remains the most potent pattern-recognition technology ever discovered: the human brain.Ultimately, Seung still hopes that artificial intelligence will be able to handle the entire job. But in the meantime, he is working to recruit more help. In August, South Korea’s largest telecom company announced a partnership with EyeWire, running nationwide ads to bring in more players. In the next few years, Seung hopes to go bigger by enticing a company to turn EyeWire into a game with characters and a story line that people play purely for fun. “Think of what we could do,” Seung said, “if we could capture even a small fraction of the mental effort that goes into Angry Birds.”
No doubt we will learn something from the connectome of a single brain, but what? What generalizations can we make from the connectome of a single brain? 10 brains, 100 brains, a thousand, ten-thousand? And these are necessarily brains of dead people. It would be nice to follow the connectome of a single brain over time, year by year, month by month, day by day...hour by hour? Imagine, for a moment, that we could do that. Much of the value in that effort would be in tracking the connectivity of individual neurons from one moment to the next. To do that, though, we need to be able to assign a unique identifier to each neuron and then track that identifier from one measurement period to the next. How would we do that?
And then there is this:
And then there is this:
Eve Marder, a prominent neuroscientist at Brandeis University, cautions against expecting too much from the connectome. She studies neurons that control the stomachs of crabs and lobsters. In these relatively simple systems of 30 or so neurons, she has shown that neuromodulators — signaling chemicals that wash across regions of the brain, omitted from Seung’s static map — can fundamentally change how a circuit functions. If this is true for the stomach of a crustacean, the mind reels to consider what may be happening in the brain of a mouse, not to mention a human.
I'm thinking that if all goes well, in a decade or so the connectomitrists will examine their work, rethink, and do something else, something that we and they could not otherwise have imagined.
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Here's an old post of mine–well, the post isn't so old, but it consists of notes that are at least a decade old–that talks a bit about neural connectivity and identity in the context of direct brain-to-brain communication.