Consciousness as a brain function
May 25, 2025 at 7:34 am
(This post was last modified: May 25, 2025 at 7:41 am by Alan V.)
I typed up this summary of points specifically for this forum, though I had created a longer version earlier.
According to the book Consciousness and the Brain by Stanislas Dehaene, a professor of experimental cognitive psychology, scientists studying conscious access to information, by comparing brain scans with subjective reports from experiments playing with threshold conditions, came to the following conclusions.
* Certain "patterns of neural activity are exclusively associated with conscious processing." Others are unconscious stimuli processing.
* The signatures of consciousness include:
1) "a sudden ignition of parietal and prefrontal circuits" which is similar to a phase transition between unconscious and conscious processing,
2) a P3 wave, a late slow wave, 1/3 to 1/2 second after a stimulus,
3) "a late sudden burst of high-frequency [gamma band] oscillations,"
4) "a synchronization of information exchanges across distant brain regions."
* To compensate for the lag-time of consciousness per the second signature, much of our behavior works on autopilot and many of our perceptions work in anticipation of what we will perceive.
* A huge amount of unconscious processing of information occurs in our brains without becoming conscious.
* Information can register and stay in an unconscious buffer temporarily, but can be erased by distractions.
* Humans make terrible witnesses. We suffer from inattentional blindness and change blindness to what we haven't attended to properly.
* Information can be readily available in the brain without becoming conscious, due to the rivalry for conscious access.
* Paying attention therefore plays a big role in what information becomes conscious.
* "Conscious perception relies predominantly on the higher-level association cortex."
* Most all the brain's regions can participate in both conscious and unconscious thought.
* Emotional appraisals are made quickly and unconsciously by the amygdala.
* Unconscious priming speeds up processing. "Repetition leads to facilitation even when it goes totally undetected."
* "What we experience as a conscious visual scene is a highly processed image, quite different from the raw input that we receive from the eyes."
* Consciousness requires attention, but attention can operate independently of consciousness. Unconscious attention is constantly monitoring.
* Assigning values can be unconscious and can guide behaviors, so we constantly overestimate the role that consciousness plays in our lives.
* Still, unconscious hunches require conscious verification.
* Subliminal perceptions exist and mental processes can be launched without consciousness. In most cases, they do not run to completion.
* Just about any brain process can operate unconsciously.
* "Unconscious information remains confined to a narrow brain circuit, while consciously perceived information is globally distributed to the vast majority of the cortex for an extended time." Or as Daniel Dennett said, consciousness is "fame in the brain." It is brain-wide information sharing. This additional functionality enables certain unique information-processing abilities. It allows us to keep information in mind, imprint it on our memories, and process it in various ways by routing it to different specialized brain functions. This is the global neuronal workspace hypothesis.
"Equally fundamental to the global neuronal workspace is its autonomy. Recent studies have revealed that the brain is the seat of intense spontaneous activity. It is constantly traversed by global patterns of internal activity that originate not from the external world but from within, from the neurons' peculiar capacity to self-activate in a partly random fashion." "The outcome, I argue, is a 'free-willing' machine that resolves Descartes's challenge and begins to look like a good model for consciousness." "Stimulus-evoked activity accounts for only a very small amount of the total energy consumed by the brain, probably less than 5 percent. The nervous system primarily acts as an autonomous device that generates its own thought patterns."
"Our belief in free will expresses the idea that, under the right circumstances, we have the ability to guide our decisions by our higher-level thoughts, beliefs, values, and past experiences, and to exert control over our undesired lower-level impulses." About such decisions, the author considers "their fundamental indeterminacy (a dubious idea) and their autonomy (a respectable notion)." "Autonomy is the primary property of the nervous system." Through "purposeful exploratory behavior ... during brain development, the relevant patterns are preserved while the inappropriate ones are weeded out" in a Darwinian selection process. Variations are followed by selection.
Consciousness performs an executive role, like the spokesman for a large organization. Unconscious processes are fast and parallel. Conscious processes are slow and serial. "Consciousness gives us the power of a sophisticated serial computer." "Complex strategies, formed by stringing together several elementary steps what computer scientists call algorithms' are another of consciousness's uniquely evolved functions." "The capacity to synthesize information over time, space, and modalities of knowledge, and to rethink it at any time in the future, is a fundamental component of the conscious mind, one that seems likely to have been positively selected for during evolution." Effectively, we possess "a hybrid serial-parallel machine" to process information.
My additional comments: So consciousness is an evolved brain function, and not, in fact, our self -- though it is an important part of our self. This important research demonstrates that the separable-soul theory of consciousness is nonsense. Consciousness seems like something other than physical only because it works by information processing, but that processing is entirely dependent on the brain as the research above demonstrated. In fact, our bodies are our selves and are much older evolutionarily than the more recent development of human-level consciousness as an additional brain function.
According to the book Consciousness and the Brain by Stanislas Dehaene, a professor of experimental cognitive psychology, scientists studying conscious access to information, by comparing brain scans with subjective reports from experiments playing with threshold conditions, came to the following conclusions.
* Certain "patterns of neural activity are exclusively associated with conscious processing." Others are unconscious stimuli processing.
* The signatures of consciousness include:
1) "a sudden ignition of parietal and prefrontal circuits" which is similar to a phase transition between unconscious and conscious processing,
2) a P3 wave, a late slow wave, 1/3 to 1/2 second after a stimulus,
3) "a late sudden burst of high-frequency [gamma band] oscillations,"
4) "a synchronization of information exchanges across distant brain regions."
* To compensate for the lag-time of consciousness per the second signature, much of our behavior works on autopilot and many of our perceptions work in anticipation of what we will perceive.
* A huge amount of unconscious processing of information occurs in our brains without becoming conscious.
* Information can register and stay in an unconscious buffer temporarily, but can be erased by distractions.
* Humans make terrible witnesses. We suffer from inattentional blindness and change blindness to what we haven't attended to properly.
* Information can be readily available in the brain without becoming conscious, due to the rivalry for conscious access.
* Paying attention therefore plays a big role in what information becomes conscious.
* "Conscious perception relies predominantly on the higher-level association cortex."
* Most all the brain's regions can participate in both conscious and unconscious thought.
* Emotional appraisals are made quickly and unconsciously by the amygdala.
* Unconscious priming speeds up processing. "Repetition leads to facilitation even when it goes totally undetected."
* "What we experience as a conscious visual scene is a highly processed image, quite different from the raw input that we receive from the eyes."
* Consciousness requires attention, but attention can operate independently of consciousness. Unconscious attention is constantly monitoring.
* Assigning values can be unconscious and can guide behaviors, so we constantly overestimate the role that consciousness plays in our lives.
* Still, unconscious hunches require conscious verification.
* Subliminal perceptions exist and mental processes can be launched without consciousness. In most cases, they do not run to completion.
* Just about any brain process can operate unconsciously.
* "Unconscious information remains confined to a narrow brain circuit, while consciously perceived information is globally distributed to the vast majority of the cortex for an extended time." Or as Daniel Dennett said, consciousness is "fame in the brain." It is brain-wide information sharing. This additional functionality enables certain unique information-processing abilities. It allows us to keep information in mind, imprint it on our memories, and process it in various ways by routing it to different specialized brain functions. This is the global neuronal workspace hypothesis.
"Equally fundamental to the global neuronal workspace is its autonomy. Recent studies have revealed that the brain is the seat of intense spontaneous activity. It is constantly traversed by global patterns of internal activity that originate not from the external world but from within, from the neurons' peculiar capacity to self-activate in a partly random fashion." "The outcome, I argue, is a 'free-willing' machine that resolves Descartes's challenge and begins to look like a good model for consciousness." "Stimulus-evoked activity accounts for only a very small amount of the total energy consumed by the brain, probably less than 5 percent. The nervous system primarily acts as an autonomous device that generates its own thought patterns."
"Our belief in free will expresses the idea that, under the right circumstances, we have the ability to guide our decisions by our higher-level thoughts, beliefs, values, and past experiences, and to exert control over our undesired lower-level impulses." About such decisions, the author considers "their fundamental indeterminacy (a dubious idea) and their autonomy (a respectable notion)." "Autonomy is the primary property of the nervous system." Through "purposeful exploratory behavior ... during brain development, the relevant patterns are preserved while the inappropriate ones are weeded out" in a Darwinian selection process. Variations are followed by selection.
Consciousness performs an executive role, like the spokesman for a large organization. Unconscious processes are fast and parallel. Conscious processes are slow and serial. "Consciousness gives us the power of a sophisticated serial computer." "Complex strategies, formed by stringing together several elementary steps what computer scientists call algorithms' are another of consciousness's uniquely evolved functions." "The capacity to synthesize information over time, space, and modalities of knowledge, and to rethink it at any time in the future, is a fundamental component of the conscious mind, one that seems likely to have been positively selected for during evolution." Effectively, we possess "a hybrid serial-parallel machine" to process information.
My additional comments: So consciousness is an evolved brain function, and not, in fact, our self -- though it is an important part of our self. This important research demonstrates that the separable-soul theory of consciousness is nonsense. Consciousness seems like something other than physical only because it works by information processing, but that processing is entirely dependent on the brain as the research above demonstrated. In fact, our bodies are our selves and are much older evolutionarily than the more recent development of human-level consciousness as an additional brain function.
