How Consciousness Might Have Evolved

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Human consciousness. Our wonderful, crazy mind. Our personhood. And our quandary. Where did consciousness come from? How did it become part of us?

Michael Graziano, a neuropsychologist I’ve posted about before, writes in the June 2016 Atlantic about how consciousness might have evolved. He starts with the question that evolutionists ask about any feature of an organism: What is its adaptive value?

The answer, he writes, is that consciousness is a sophisticated solution to a difficulty that plagues the nervous system of all creatures: “Too much information constantly flows in to be fully processed.” It’s an old dilemma, with early fixes. Even before the formation of brains, nervous systems 600 million years ago enhanced certain nerve signals at the expense of others. The eyes of insects and crabs, for example, generate “an outline sketch of the world” as the signals carrying visual data about the edges of objects are stronger than other visual signals.

Then around 500 million years ago, a controller in the early brains of fish and reptiles began coordinating several senses at a time, “aiming the satellite dishes of the eyes, ears, and nose towards anything important.” The controller did so by generating an internal model, a set of information about the current state of the body parts, and predicting “how these body parts will move next and about the consequences of their movement.” If you had only a reptilian controller for a brain, you would look at the steps in front of you and the controller would check those nerve signals against its model of where your legs ought to be to get you up the steps successfully.

But we have much more than a controller. Some mammals, including us, have the latest upgrade, the cerebral cortex. We can pay attention to something we are not even focused on at the moment—the TV in the other room, for instance—because our cortex can select what to select. What’s more, we can even be self-aware that we are doing so. “I’m not going to go in there, but he’s watching that news again” (my example). Humans can do this because our upgraded controller uses schemas, models of not only all that we know but also of our attention itself. Our brain tracks “what covert attention is doing moment by moment and what its consequences are.” This is where we get that self-aware voice inside us that tells us, “I’ve got something intangible inside me. It moves around from one thing to another and allows me to understand and remember.”

Such evolution of consciousness goes hand in hand with our social evolution, according to Graziano. Animals acquired the capacity to be aware of the mind of other members of their species. Social awareness and self-awareness have evolved “in tandem….We understand other people by projecting ourselves onto them. But we also understand ourselves by considering the way other people might see us.” Consciousness tracks and grows from our social life and our social self.

Graziano acknowledges that the schema theory of consciousness is still new, but he believes it “provides a general framework” for understanding consciousness and its evolution. It seems to me that it does so very well. It’s difficult for us to see our minds in physical terms because we have that voice in our head that insists, “Wow! I’m thinking and feeling all this!” Glowing with this cerebral radiance, we easily believe we carry an ethereal self, even an undying soul. But it is thrilling to me to understand the splendor of consciousness not as an outlier in nature but as a thoroughly earthly step in the push of small, accidental, pragmatic adjustments that is physical life.

 

Michael Graziano on How the Brain Creates Consciousness and Spirituality

Psychologist Michael Graziano proposes that our consciousness is more mechanical and less mysterious than we think. But he argues as well that this theory does not diminish the validity of our spiritual experiences.

Graziano, in Consciousness and the Social Brain, fully appreciates what our consciousness, our awareness, means to us. It is “the spark that make us us. Something lovely apparently buried inside us is aware of ourselves and of our world” (Kindle location 66). And many of us believe this lovely spark to be our spirit, even our soul.

 (langmaidpractice.com)

(langmaidpractice.com)

But how does it work? Despite all that neuroscientists know about the brain, what remains elusive is how it goes about giving us the experience of being aware, awake, taking it all in. Theories suggest that the brain’s signals are “boosted, improved, maintained, or integrated” in some way that creates the sensation of awareness. But they don’t say how.

Graziano’s explanation is not really complicated, but it is so different from our everyday experience that it helps to understand first the main concept that it is built on, one that is well-established in neuroscience. This concept is that the brain recognizes things because it makes simplified models of them, shorthand versions that are similar to codes or diagrams. Examples of these schema include the formula a child’s brain will store away for identifying a dog (four legs, fur, friendly) and the sequence that adults know for entering a restaurant and ordering food. The brain stores such schemas and uses them to identify and even to imagine.

Schema theory is popular in early education. (4.bp.blogspot.com)

Schema theory applied in early education.
(4.bp.blogspot.com)

The twist that Graziano adds to the schema idea is that our consciousness itself is a schema, the brain’s shorthand version of the act of paying attention. “In the present theory, awareness is an attention schema. It is not attention but rather a simplified, useful description of attention” (377). As for attention itself, it is an actual, physical activity; it “lights up” sections of the brain in ways we can take pictures of. The attention schema, on the other hand, is a simplified model of that activity as it is stored by the brain.

Here is Graziano’s proposal in a nutshell. Take the example of a moment when we look at the bright green of spring and think, perhaps wordlessly, wow, what a bright, lovely green.

Suppose that you are looking at a green object and have a conscious experience of greenness. In the view that I am suggesting, the brain contains a chunk of information that describes the state of experiencing, and it contains a chunk of information that describes spectral green. Those two chunks are bound together. In that way, the brain computes a larger, composite description of experiencing green. (317)

Once that description is in place, other parts of our brain can verbalize it. We can say, “The green on this leaf is beautiful.” We are not experiencing green directly; a “color” is physically only electric and magnetic waves. We are experiencing the brain’s combination of two of its descriptions, the schema of greenness and of conscious attention.

Such a view has prompted me to experience my own conscious awareness a little differently. I think it is like a camera that clicks twice every time it takes a picture. One click is the picture of the object in front of it, the second click is the camera recording that it took a picture. When I think to myself, like the man in the cartoon above, “I’m standing here” or some other self-aware thought, there is a click of noticing what’s around me and a click of noticing my noticing.

Graziano adds that the attention schema comes with a GPS marker. The GPS usually locates the attention experience as “inside our head.”

But often it locates awareness inside someone else’s head, when we are imaging what other people might be thinking, saying, planning.

Or it might locate awareness in our dog, in thunderstorms, in luck, or in a god. Or floating above our body when our brain is compromised during surgery and we have a near-death experience. And Graziano,  a “passable” ventriloquist, notes how readily an audience will locate awareness and attention in a wooden dummy.

Finally, one might expect a prominent psychologist such as Graziano to take a dim view of religious and superstitious beliefs. But in fact he eloquently embraces spirituality in particular. It is, after all, a matter of consciousness.

(bespirituality.com)

(bespirituality.com)

To me personally, the most reasonable approach to spirituality is to accept two simultaneous truths. One, literally and objectively, there is no spirit world. Minds do not float independently of bodies and brains. Two, perceptually, there is a spirit world. We live in a perceptual world, a world simulated by the brain, in which consciousness inhabits many things around us, including sometimes empty space….The perceptual world and the objective world do not always match. We sometimes must live with both sets of knowledge. Neither side can be ignored. (2946)

In the present hypothesis, people intuitively understand consciousness to be spirit-like because the information representation in the brain encodes it in that manner. [The spirit concept,] the diaphanous invisible stuff that thinks and perceives and flows plasma-like through space and time,… that normally inhabits the human body but can sometimes flow outside of it, and that therefore ought to be able to survive the death of the body—this myth so ubiquitous in human culture is not a mistaken belief, a naïve theory, or the result of superstitious ignorance, as many scientists would claim. It is instead a verbalization of a naturally occurring informational model in the human brain. (1154)

For me, Graziano’s work affirms the spiritual value I find in the presence and the history of living things. This is not only because of his acceptance, just described, of people’s spiritual awareness. It is also because his analysis of consciousness helps me to see it as the work of natural selection. I see human consciousness as a unique elaboration of the capacities for perception and memory that are found in simpler forms in the brains of other and earlier animals.