“Dropping into the world with a half-baked brain has proven a winning strategy for humans. We have outcompeted every species on the planet: covering the landmass, conquering the seas, and bounding onto the moon. We have tripled our life spans. We compose symphonies, erect skyscrapers, and measure with ever-increasing precision the details of our own brains. None of those enterprises were genetically encoded. At least they weren't encoded directly. Instead, our genetics bring about a simple principle: don't build inflexible hardware; build a system that adapts to the world around it. Our DNA is not a fixed schematic for building an organism; rather, it sets up a dynamic system that continually rewrites it's circuitry to reflect the world around it and to optimize its efficacy within it.” - David Eagleman, Livewired: The Inside Story of the Ever-Changing Brain
As the most unique and complex object in the known universe, it can be difficult to get a grasp on what the brain is, exactly. It can be tempting to equate the brain to some upscaled version of an electronic computer; after all, we have reached a point in artificial intelligence where computers can run programs that change themselves in response to information, effectively learning and updating just like our brain does, right?
As we traverse and experience the world, our “software” does indeed get updated: we form new memories, beliefs, thought patterns, etc. But, crucially, our “hardware” changes as well. The physical structure of our brain is constantly in flux, responding morphologically to every thought and experience we have. As you read this sentence, the cells in your brain cells are shifting, branching, sending slithering dendrites out to encode every new bit of information you encounter. Your brain is not a fixed computer running the program that is you. Your brain is you, and every tiny change in your thinking is the product of a structural change in your brain.
The magic of the human species, the competitive advantage that has allowed us to exercise stunning creativity and conquer the entire planet, is the astounding flexibility of our brains. We come pre-packaged with the bare essentials, and then we rely fully on the malleable blob in our skull to learn and change and adapt to the environment. The human brain builds and programs itself as it goes through life. It is “livewired.”
Eagleman makes us wonder at the ingenious freedom that our brain provides us, and that has allowed humans to thrive in every corner of the globe. He includes stunning anecdotes about the brain’s resilience, including the story of a young man who had an entire hemisphere of his brain removed to treat debilitating seizures. Miraculously, he was able to regain almost all of his cognitive functions and hold down a stable job, all with literally half a brain!
David Eagleman is a Stanford University neuroscientist and best-selling author. If you want to better understand the brain and how we’re set up to interact with the world around us, you can get a copy of Livewired on Amazon. We highly recommend it.
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