IS THIS WHAT A HUMAN IS?
Do you know what a connectome is? It could be a source of science fiction stories for one thing. Sebastian Sueng says in his TED talk, “I am my connectome. I am more than my genes.” The connectome is the pattern of connections between neurons in our brains that may very well establish who we are as human beings. Read on to find out more, and among other things, see what sci fi stories you can come up with.
You may be looking at the single most complex object in the known universe, and it’s inside all of our heads. Okay, well, most of us–we all know an exception or two. A human brain has about 100 billion neurons.From Wikipedia: A neuron is a special type of cell that is found in the bodies of most animals (all members of the the group Eumetozoa, to be precise–this excludes only sponges and a few other very simple animals. The features that define a neuron are electrical excitability and the presence of synapses, which are complex membrane junctions used to transmit signals to other cells.
Each one of these neurons has over 10,000 times as many connections to other neurons. Each one of these connections is a branch from the neuron to a synapse, connecting the neuron to a branch of another neuron. That is a lot of connections.
Consider 100,000,000,000 is the number of neurons. The connections are 10,000 x 100,000,000,000 = 1,000,000,000,000,000 or one quadrillion. Stay with me, (I’m such a geek, I love this stuff) I just want to give you a small idea how large a number that is. If you were to count to a trillion, you know: one, two, three and so on to a trillion, it would take about six seconds on average to pronounce all the syllables in each number because nearly all of them, by comparison, are huge, say for instance 369,472,888,227. You’d say, “three hundred sixty-nine billion, four hundred seventy-two million, eight hundred eighty-eight thousand, two hundred twenty-seven,” (in case you’re interested, you’d be over a third of the way to a trillion by the time you said that particular number). That’s six trillion seconds. It would take you 190,259 years, which is about as long as humans have lived on this planet (6,000,000,000,000 seconds divided by 60 seconds per minute divided by 60 minutes per hour divided by 24 hours per day divided by 365 days per year = 190,259 years). That’s only a thousandth of a quadrillion. It would take hundreds of millions of years to count that. As far as we are concerned on any scale of our imaginations, a quadrillion connections might as well be infinite.
So, again, that’s a lot of connections. It’s actually a million times more connections than our genome has letters. This incredibly complex pattern of living electrochemical activity, the connectome, may very well be us, our personalities and memories. This is what leads Sebastian Sueng to say, “I am my connectome.” We have mapped the human genome using powerful computers. Sebastian says it will take generations to map one connectome. The total length of “wires” in all those branches from the neurons to the synapses in your brain, is in the millions of miles. Yes, that’s all stuffed up there in your pointy little noggin.
Now here’s the point I’m getting at, which begins to set part of the foundation for the ongoing conversation that is my life’s work. It’s at the heart of my novels. It’s a question Sebastian asks, “What causes synaptic and neuronal changes? What if neural activity can change the connectome? Then the brain, or more accurately, who we are, is malleable. Neural activity is the water, the bed is the connectome, water can reshape the bed as neural activity reshapes the connectome. This is freedom. This is what intentional evolution looks like.
A critical thing to get here is this scientific work by Sebastian Sueng and his colleagues is a story. An elegant, beautiful story with a high degree of integrity that matches what we experience. It is not the truth, nor is it a fact.
In the science fiction story category, you may ask is death the end of the connectome? Can we preserve the connectome? Someday, once we are able to map the nearly infinite complexity of the connectome, will we be able to construct, or reconstruct our brains. What do you think? What’s coming up for you out of reading this? Inviting your comments here.
One last thing, a little more science fiction: I don’t know if you’ve ever heard the word connectome spoken, but if I had never heard it pronounced as connect-tome (tome, as in a large, heavy book, or volume–as the word is derived from the same base as genome) I’d have read it as “connect-to-me.” A message from the spirit world of our ancestors? What if that massively complex pattern of connections is not limited to existing inside a human skull? What if we are not a closed system?