(January 11, 2019 at 8:31 am)Belaqua Wrote: Thank you for pointing out the book to me.
Okay, so this is my short summary of some of the main points from
The Consciousness Instinct: Unraveling the Mystery of How the Brain Makes the Mind by Michael Gazzanina. If you are reading the book too, you can add to what I have said since I didn't understand some sections.
In his introduction, the author states that he wants “to examine how matter makes minds.” He thinks “consciousness is an instinct. Many organisms, not just humans, come with it, ready-made.” Further, he states, “We are each a confederation of rather independent modules, orchestrated to work together.”
After reviewing the history of western philosophical and empirical thinking about the mind/brain problem in the first two chapters, the author lists several of the important scientific discoveries about consciousness from the last century. These include:
1) Penfield’s discovery of how the human body was mapped out in brains,
2) The discovery that “consciousness is inevitably lost when the function of the higher brain stem is interrupted.” This is interpreted to mean that consciousness depends on the “combined functional activity in the diencephalon [the higher brain stem or mid-brain] and cerebral cortex, not within the diencephalon alone.” In other words, consciousness does not exist in just one place in the brain.
3) The discovery that the brain is modular, which means that it is highly specialized functionally. Even different aspects of language are controlled by different parts of the brain (Broca’s area and Wernicke’s area). Such modules have a high number of connections within them, but only a few to other modules.
4) The discovery that epileptics who had their corpus callosum cut, severing the connections between the brain’s hemispheres to prevent seizures, clearly demonstrated they had two independent minds subsequently, but sharing the same emotions and motivations from the mid-brain. These minds did not share information as before, however, and therefore were distinctly different than they were in combination.
Gazzanina and Roger Sperry studied such split-brain patients together. From such studies, Sperry concluded that conscious experience is a property of brain activity which is:
1) nonreductive (it can’t be broken down into its parts),
2) dynamic (it changes in response to neural activity),
3) and emergent (it is more than the sum of the processes that produce it).
He also concluded “it could not exist apart from the brain.”
Francis Crick and Christof Koch concluded that “at any one moment some active neuronal processes correlate with consciousness, while others do not.” In other words, the brain is active in performing other functions than consciousness. Nevertheless, “there must be an explicit correspondence between any mental event and its neuronal correlates.”
More and more progress was made assigning specific functions to specific brain areas through a study of patients with various brain injuries. One discovery was that a kind of basic consciousness was very difficult to eradicate through specific brain injuries, and that patients were only aware of the brain circuits which were still working. For instance, people who were missing half of their visual field still thought they were seeing everything they could before. “If we lose a particular function, we lose the consciousness that accompanies it, but we don’t lose consciousness altogether.” Another discovery was that some circuits out-compete others for conscious attention. In other words, even when modules are fully functional and processing information, not all rise to awareness. Yet another discovery was that the brain was arranged hierarchically. Some modules have submodules with their own submodules.
“The perks of brain modularity are that it saves energy when resources are scarce, allows for specialized parallel cognitive processing when time is limited, makes it easier to alter functionality when new survival pressures arise, and allows us to learn a variety of new skills.”
Also, humans “possess highly integrative modules, which allow us to combine information from various modules into abstract thoughts.”
Because the matter which makes up the brain changes with some frequency through metabolism, replication, and repair, the functionality of the brain resides in its organization, and that “organization must be independent of the material particles that make up a living system.”
Like most biological systems, brains have a layered architecture. Levels are in series, but layers are in parallel, and can work independently and simultaneously. Information which is passed upwards is abstracted. “The purpose of each layer is to serve the layer above it while concealing the processes of the lower layer.” The lower layers are the most fixed and automatic. The higher layers are the most modifiable and least automatic. Evolution built the higher layers on the lower. “Overall, a layered architecture is ideal for complex systems because it is easily fixable, less costly, more flexible, and evolvable.”
Roger Sperry said,“View the brain objectively for what it is, namely, a mechanism for governing motor activity.” The brain is a motor control system for the body, which uses thinking, planning, remembering, learning, and cognition to guide its actions. “The more experiences you have had, the more choices your brain can simulate.”
“It is the mid-brain that supports the basic capacity for conscious subjective experiences.” It sustains emotional and motivational feelings, including “seeking, fear, rage, lust, care, grief, and play.” The frontal lobe controls such emotions. “Losing modules causes losses in specific funtionalities, but the mind keeps on producing a continuous conscious stream as if nothing changed. The only things that have changed is the contents of that stream. Not only does this provide evidence that the brain operates in a modular fashion, but it also suggest that independent modules can each produce a unique form of consciousness.”
From our understanding of quantum mechanics, we now know that objectivity does not just pertain to what is inherent entirely in a material system, but to what is inherent in a system-observer pair. “By the mere fact of measuring you are introducing subjectivity into the system.” This is complementarity, and it is an important concept in approaching the mind/brain problem. Howard Pattee pointed out that “it was the belief that human consciousness ultimately collapsed the wave function that produce the problem of Schrodinger’s cat.” But Pattee suggested that natural mechanisms far simpler than human consciousness could do this, and he proposed that the gap between inanimate and living matter resulted from “a process equivalent to quantum measurement that began with self-replication at the origin of life.” In other words, subjectivity was born with life, not with consciousness, which was a later elaboration. He stated, “Duality is a necessary and inherent property of any entity capable of evolving” and “if we want to understand the idea of consciousness, something fully formed in evolved living systems, we must first understand what makes a living system alive and evolvable in the first place.”
“Any living thing that ‘records’ information is introducing a form of subjectivity into the system.” A symbol is arbitrary, so while natural laws are inexorable and universal, rules that apply to symbols can be changed and are arbitrary. Pattee asserted that “it is precisely this natural symbol-matter articulation that makes life distinct from non-living physical systems.”
Biosemiotics is the semiotics of living systems. Semiotic systems pair signs and meanings with a code which is included within the system itself, and not imposed externally. Such assignments are arbitrary, like sounds for meanings in language, and came into existence through random molecular resorting. In other words, matter can self-organize in another way besides the laws of physics or evolution. “In its informational (subjective) mode, DNA follows rules, not the laws of physics.”
“There can be no self-awareness without a self. The first steps must be toward a delimited self.” Consciousness of such a self is further down the road, and is a relatively simple matter of perceiving an already existing self. Thus consciousness depends upon discrete living systems.
“Living matter is distinct from inanimate matter because it has taken an entirely different course. Inanimate matter abides by physical laws. Life from the get-go has thrown its lot in with rules, codes, and the arbitrariness of symbolic information.” Pattee asserted, “Our models of living organisms will never eliminate the distinction between the self and the universe, because life began with this separation and evolution requires it.”
“Neural circuits are structures with a double life: they carry symbolic information, which is subject to arbitrary rules, yet they posses a material structure that is subject to the laws of physics.” With competing modules comes selective awareness, or selective signal enhancement through attention by means of a control layer.
So the machine metaphor no longer works to explain consciousness. “Brains aren’t like machines; machines are like brains with something missing. Polanyi pointed out that humans evolved through natural selection, whereas machines are made by humans. They exist only as the product of highly evolved living matter, and are the end product of evolution, not the beginning.”