Reading her piece was like listening to my neighbor Greg explain Einstein's Theory of Special and General Relativity. I get it when he's explaining it, but by the time I get to the top of the stairs to my apartment, it's gone. I've asked Greg to tell me the story a couple of times. I'll get it eventually because he's starting to use more graphic explanations.
Right now, the only thing that I know I will remember from Dougherty's piece is this:
"Trying to imagine how trillions of connections and billions of simultaneous transmissions coalesce inside your brain to form a thought is a little like trying to look at the leaves, roots, snakes, birds, ticks, deer—and everything else in a forest—at the same moment."
In the meantime and for anyone who gives a damn, here are more technical excerpts from Dougherty's piece:
"Thoughts are... really just electro-chemical reactions...
The human brain is composed of about 100 billion nerve cells (neurons) interconnected by trillions of connections, called synapses. On average, each connection transmits about one signal per second. Some specialized connections send up to 1,000 signals per second. “Somehow… that’s producing thought,” says Charles Jennings, director of neurotechnology at the MIT McGovern Institute for Brain Research.
Given the physical complexity of what’s happening inside your head, it’s not easy to trace a thought from beginning to end. “That’s a little like asking where the forest begins. Is it with the first leaf, or the tip of the first root?” says Jennings.
Simpler, then to start by considering perceptions—“thoughts” that are directly triggered by external stimuli—a feather brushes your skin, you see these words on the computer screen, you hear a phone ring. Each of these events triggers a series of signals in the brain.
When you read these words, for example, the photons associated with the patterns of the letters hit your retina, and their energy triggers an electrical signal in the light-detecting cells there.
That electrical signal propagates like a wave along the long threads called axons that are part of the connections between neurons.
When the signal reaches the end of an axon, it causes the release of chemical neurotransmitters into the synapse, a chemical junction between the axon tip and target neurons.
A target neuron responds with its own electrical signal, which, in turn, spreads to other neurons.
Within a few hundred milliseconds, the signal has spread to billions of neurons in several dozen interconnected areas of your brain and you have perceived these words."
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