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Consciousness: How does the brain make the mind?
In his new book, The Consciousness Instinct, Michael Gazzaniga does a deep dive into the process of consciousness.
When you wake up in the morning, it’s likely you remember who you were when you turned off the lights the previous evening. Sleep being a brief respite, you’re ready to continue being you again. In fact, you have been you seamlessly since the day you were born. There’s much you’ve forgotten and much you misremember, even though you won’t believe you’ve remembered it wrong. Otherwise, consciousness has been humming along on a smooth trajectory the entire time, right?
If only consciousness worked that way. Then again, if it did, it wouldn’t be who we are. Part of the problem resides in agreeing on a definition. As neuroscientist Michael Gazzaniga writes in his new book, The Consciousness Instinct: Unraveling the Mystery of How the Brain Makes the Mind, quoting the linguist Noam Chomsky, consciousness is a “word worn smooth by a million tongues.”
To keep it simple, Gazzaniga writes that consciousness “is the word we use to describe the subjective feeling of a number of instincts and/or memories playing out in time in an organism.” Whatever captures our attention at that moment is what exists in our consciousness. The rest of everything else, from the innumerable autonomic processes keeping our body in homeostasis to the innumerable processes keeping the planet in homeostasis, remains hidden.
Despite the fact that some might be upset upon learning that consciousness—the very quality we believe lifts us above the rest of the animal kingdom—is an instinct, Gazzaniga is undeterred in his assumption. Being an instinct takes nothing away from the mystery of existence; if anything, it deepens our appreciation for just how embedded this phenomenon is in the fabric of life. As he recently told me:
By calling it an instinct, I'm saying whatever it is we're talking about, it comes with us.
A feature, not a bug, and not unique. In the book he notes that this instinct predates the first organisms, borrowing from William James. An instinct is, first and foremost, felt. Feelings eventually give rise to cognition; in this sense, cognition is the way we translate sensations. The fundamental requirements of life—sustenance; reproduction—were initially acquired through sensations of feeling. Only later did more advanced forms of life add complexity to the process we now term consciousness. Even today, emotions, the term we assign for different feelings, must be considered the “foundational component of consciousness.”
Gazzaniga has long known about our brain’s fragmented nature. In 1964 he began working on split-brain research, helping to initiate research on functional lateralization in the brain. When the corpus callosum is severed, each hemisphere has its own perceptual and conceptual systems, effectively creating two brains in one person. Gazzaniga’s work changed the field of neuroscience. No longer could consciousness be thought of as a seamless experience generated by one system or network.
Professor Michael Gazzaniga, Director of Program in Cognitive Neuroscience at Dartmouth College. Dr. Michael Gazzangia is a veteran neuroscientist and a fledgling bioethicist as a member of President George W. Bush's Council on bioethics. (Photo by Rick Friedman/Corbis via Getty Images)
Despite the fact that it feels like we have an uninterrupted consciousness (save the third of our life we spend asleep), this phenomenon is actually produced by “thousands of relatively independent processing units.” In other words, modules. Gazzaniga writes that everything we subjectively experience is the result of a brain organized into modules of functionally interconnected regions. There is no localizable consciousness center.
With this book, he attempts to once again push the field forward. To explain modularity Gazzaniga explores physics and architecture, using the Boeing 777 as an example. Comprised of 150,000 subsystem modules networked by 1,000 computers, each engineer does not need to know how the entire system operates to understand the role they play. Without one subsystem the plane does not function as intended—think neurological damage to one system. Damage too many and the machine fails. Yet the layering of numerous systems creates the intended effect, just as it does in human consciousness.
Not to abuse the machine metaphor, however. As Gazzaniga writes:
Brains aren’t like machines; machines are like brains with something missing.
Which brings us to one of the most fascinating and debated aspects of neuroscience: the idea of a soul being the catalyst for consciousness, or at least a separate layer uninvolved in the body’s physical structure. Extending the architecture motif, Gazzaniga notes that at the most fundamental level, architecture, and in this analogy, consciousness, is “design within the bounds of constraints.”
How exactly the brain makes the mind—along with its necessary partners, the body and environment—might always remain hidden given the complexity of layering involved. That does not imply that consciousness is possible without the layered architecture existent in the body. In our conversation, he summed up three main theories of mind:
There’s no loose bolts in there. There’s no magic. But there are basically three ideas in human history about the relationship of brain and body. One is that the brain generates the mind. That’s the full story. Another one is the brain generates the mind, but there’s an added commodity called the spirit or soul that survives death. Then there’s a third one, which is dualism. And those three ideas are still with us.
Just as the “ghost in the machine” is an illusion created by the many layers of consciousness, so is the notion of a smoothly flowing consciousness. Rather, Gazzaniga writes that consciousness is more like a series of “cognitive bubbles linked with subcortical ‘feeling’ bubbles, stitched together by our brain in time.” This notion is born out in memory research. We don’t recall past experiences perfectly. Rather, everything that has happened since will alter the event we’re recalling.
As Gazzaniga writes, our feelings about past moments are not actually the feelings we had during the event. We’re experiencing our current feelings, mapping them back through time in a remix of our former self. We might remember a date we had a decade ago differently on Tuesday than on Monday depending upon our current mood, so fragile is this system.
And yet, as Gazzaniga describes the brain as a whole, “fragile yet robust.” While we might never know exactly how the brain makes the mind, we won’t find the secret in one system alone. Existence is too complex for that, no matter how much we prefer simple explanations. That doesn’t make the complexity any less fascinating.
These alien-like creatures are virtually invisible in the deep sea.
- A team of marine biologists used nets to catch 16 species of deep-sea fish that have evolved the ability to be virtually invisible to prey and predators.
- "Ultra-black" skin seems to be an evolutionary adaptation that helps fish camouflage themselves in the deep sea, which is illuminated by bioluminescent organisms.
- There are likely more, and potentially much darker, ultra-black fish lurking deep in the ocean.
The Pacific blackdragon
Credit: Karen Osborn/Smithsonian<p>When researchers first saw the deep-sea species, it wasn't immediately obvious that their skin was ultra-black. Then, marine biologist Karen Osborn, a co-author on the new paper, noticed something strange about the photos she took of the fish.</p><p style="margin-left: 20px;">"I had tried to take pictures of deep-sea fish before and got nothing but these really horrible pictures, where you can't see any detail," Osborn told <em><a href="https://www.wired.com/story/meet-the-ultra-black-vantafish/" target="_blank">Wired</a></em>. "How is it that I can shine two strobe lights at them and all that light just disappears?"</p><p>After examining samples of fish skin under the microscope, the researchers discovered that the fish skin contains a layer of organelles called melanosomes, which contain melanin, the same pigment that gives color to human skin and hair. This layer of melanosomes absorbs most of the light that hits them.</p>
A crested bigscale
Credit: Karen Osborn/Smithsonian<p style="margin-left: 20px;">"But what isn't absorbed side-scatters into the layer, and it's absorbed by the neighboring pigments that are all packed right up close to it," Osborn told <em>Wired</em>. "And so what they've done is create this super-efficient, very-little-material system where they can basically build a light trap with just the pigment particles and nothing else."</p><p>The result? Strange and terrifying deep-sea species, like the crested bigscale, fangtooth, and Pacific blackdragon, all of which appear in the deep sea as barely more than faint silhouettes.</p>
David Csepp, NMFS/AKFSC/ABL<p>But interestingly, this unique disappearing trick wasn't passed on to these species by a common ancestor. Rather, they each developed it independently. As such, the different species use their ultra-blackness for different purposes. For example, the threadfin dragonfish only has ultra-black skin during its adolescent years, when it's rather defenseless, as <em>Wired</em> <a href="https://www.wired.com/story/meet-the-ultra-black-vantafish/" target="_blank">notes</a>.</p><p>Other fish—like the <a href="http://onebugaday.blogspot.com/2016/06/a-new-anglerfish-oneirodes-amaokai.html" target="_blank">oneirodes species</a>, which use bioluminescent lures to bait prey—probably evolved ultra-black skin to avoid reflecting the light their own bodies produce. Meanwhile, species like <em>C. acclinidens</em> only have ultra-black skin around their gut, possibly to hide light of bioluminescent fish they've eaten.</p><p>Given that these newly described species are just ones that this team found off the coast of California, there are likely many more, and possibly much darker, ultra-black fish swimming in the deep ocean. </p>
How long should one wait until an idea like string theory, seductive as it may be, is deemed unrealistic?
- How far should we defend an idea in the face of contrarian evidence?
- Who decides when it's time to abandon an idea and deem it wrong?
- Science carries within it its seeds from ancient Greece, including certain prejudices of how reality should or shouldn't be.
Plato used the allegory of the cave to explain that what humans see and experience is not the true reality.
Credit: Gothika via Wikimedia Commons CC 4.0<p>When scientists and mathematicians use the term <em>Platonic worldview</em>, that's what they mean in general: The unbound capacity of reason to unlock the secrets of creation, one by one. Einstein, for one, was a believer, preaching the fundamental reasonableness of nature; no weird unexplainable stuff, like a god that plays dice—his tongue-in-cheek critique of the belief that the unpredictability of the quantum world was truly fundamental to nature and not just a shortcoming of our current understanding. Despite his strong belief in such underlying order, Einstein recognized the imperfection of human knowledge: "What I see of Nature is a magnificent structure that we can comprehend only very imperfectly, and that must fill a thinking person with a feeling of humility." (Quoted by Dukas and Hoffmann in <em>Albert Einstein, The Human Side: Glimpses from His Archives</em> (1979), 39.)</p> <p>Einstein embodies the tension between these two clashing worldviews, a tension that is still very much with us today: On the one hand, the Platonic ideology that the fundamental stuff of reality is logical and understandable to the human mind, and, on the other, the acknowledgment that our reasoning has limitations, that our tools have limitations and thus that to reach some sort of final or complete understanding of the material world is nothing but an impossible, <a href="https://www.amazon.com/dp/B01K2JTGIA?tag=bigthink00-20&linkCode=ogi&th=1&psc=1" target="_blank" rel="noopener noreferrer">semi-religious dream</a>.</p>
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