Refuting Creationisn - Understanding Consciousness - No God(s) Required

Study reveals how an anesthesia drug induces unconsciousness | MIT News | Massachusetts Institute of Technology

One of creationism beloved gaps in which they try to shoehorn their ever-shrinking little god, is a scientific explanation for consciousness.

It is true that we don't yet have an explanation for consciousness but no gap in the scientific understanding of anything has ever been filled by a god, or to be more scientific, by an unproven, undetectable supernatural entity, so it's a strangely unrealistic view of science that any (or all) of creationism's gaps, real or imaginary are going to be the exception to the rule and somehow, one day, science is going to reveal the locally popular god in all its glory, having managed to hide itself for millennia.

Being inherently unfalsifiable, of course, there is no possible scientific methodology that could reveal any specified god as the indisputable cause of any phenomenon, so creationist belief that this is about to happen is delusional.

But back to the problem of consciousness.

What is the current state of thinking on the explanation for consciousness? The explanation for consciousness remains one of the most complex and debated topics in both philosophy and science. Here is a summary of the current state of thinking on consciousness, highlighting key theories and perspectives:

1. Philosophical Perspectives:
   
   • Dualism: Originally proposed by René Descartes, dualism posits that the mind and body are fundamentally different substances. This view, however, faces challenges in explaining how non-physical mind interacts with the physical body.
   • Physicalism: This view suggests that everything about consciousness can be explained in terms of physical processes in the brain. Variants include:
     • Identity Theory: Mental states are identical to brain states.
     • Functionalism: Mental states are defined by their functional roles rather than by their physical makeup.
   • Panpsychism: This theory posits that consciousness is a fundamental feature of the universe, present to some degree in all matter.
2. Neuroscientific Approaches:
   • Global Workspace Theory (GWT): Proposed by Bernard Baars, GWT suggests that consciousness arises from the integration of information in a global workspace in the brain, where information is broadcasted to various cognitive systems.
   • Integrated Information Theory (IIT): Developed by Giulio Tononi, IIT posits that consciousness correlates with the capacity of a system to integrate information. The more integrated and differentiated the information, the higher the level of consciousness.
   • Predictive Coding: This approach suggests that the brain continuously generates and updates a model of the environment based on incoming sensory information. Conscious experience arises from the brain's predictions and the errors between predicted and actual sensory inputs.
3. Quantum Theories:
   • Orchestrated Objective Reduction (Orch-OR): Proposed by Roger Penrose and Stuart Hameroff, this theory suggests that quantum processes within microtubules in brain neurons contribute to consciousness. While intriguing, this theory is controversial and lacks empirical support.
4. Emergentist and Epiphenomenal Views:
   • Emergentism: This perspective suggests that consciousness emerges from complex interactions of simpler processes, akin to how wetness emerges from the interaction of water molecules.
   • Epiphenomenalism: This view holds that physical processes in the brain give rise to consciousness, but consciousness itself does not affect physical processes.
5. Philosophical Zombies and the Hard Problem:
   • Philosophical Zombies: The concept of philosophical zombies, proposed by David Chalmers, illustrates the "hard problem" of consciousness—explaining why and how subjective experiences arise from physical processes.
   • The Hard Problem: Chalmers distinguishes between the "easy problems" of consciousness (explaining cognitive functions) and the "hard problem" (explaining subjective experience or qualia).
6. Interdisciplinary Approaches:
   • Researchers are increasingly adopting interdisciplinary approaches, combining insights from neuroscience, psychology, computer science, and philosophy to tackle the problem of consciousness. Advances in brain imaging and artificial intelligence are contributing to this integrated effort.

In summary, the explanation for consciousness remains elusive, with various theories offering partial insights but no consensus. The interplay between empirical research and philosophical inquiry continues to drive the exploration of this profound mystery.

How did Descartes explain why consciousness can be abolished by trauma to the brain or by chemicals, showing how mind and body can't be dissociated?

René Descartes, a proponent of dualism, posited that the mind and body are distinct substances: the mind (or soul) is immaterial, whereas the body is material. Despite this dualistic framework, Descartes acknowledged the close interaction between the mind and the body, particularly through the brain.

Here are key aspects of Descartes' view on the mind-body interaction and how it addresses the impact of physical trauma or chemicals on consciousness:

1. Pineal Gland as the Seat of Interaction:
   • Descartes proposed that the pineal gland in the brain is the principal site of interaction between the immaterial mind and the material body. He believed that this small, centrally located gland could act as a mediator through which the mind influenced bodily actions and vice versa.
2. Mind-Body Causal Interaction:
   • Descartes believed that mental states could influence physical states and vice versa. For example, sensory inputs from the body could affect the mind, and the mind could initiate actions in the body.
3. Trauma and Chemicals Affecting Consciousness:
   • Descartes would likely explain that physical trauma to the brain or the introduction of chemicals disrupts the normal functioning of the pineal gland and other brain structures that mediate the mind-body interaction. Such disruptions could prevent the mind from properly receiving sensory information or exerting its influence over the body, thus leading to altered or abolished states of consciousness.
4. Dependency on Physical Structures:
   • While Descartes maintained a clear distinction between the mind and the body, he acknowledged that the mind's ability to manifest consciousness relies on the proper functioning of certain physical structures. Damage to these structures would impede the mind's operations, thereby affecting consciousness.
5. Limitations and Modern Critique:
   • Modern neuroscience has advanced significantly since Descartes' time, and his specific claim about the pineal gland has been debunked. However, his broader insight that the mind's functioning is closely tied to the brain's integrity remains relevant. Neuroscientific evidence shows that consciousness and cognitive functions are profoundly affected by physical states of the brain, supporting the notion that the mind cannot be fully dissociated from the body.

In summary, Descartes explained the effects of brain trauma and chemicals on consciousness by positing that the immaterial mind interacts with the body through the brain, particularly the pineal gland. Disruptions to this interaction due to physical damage or chemical alterations could impede the mind's ability to function, thereby affecting consciousness. While the specifics of his explanation are outdated, the underlying principle of mind-body interaction remains a key topic in contemporary discussions of consciousness.

There are two things we know for sure about consciousness, (and I don't for one moment believe only humans are conscious - too much animal behaviour can't be explained other than by the animal being self-aware and having thought processes by which it plans its behaviour).

1. Consciousness cannot be dissociated from neural activity.
2. Consciousness can be altered or abolished by brain injury or chemicals (anesthetics, mind-altering drugs, alcohol, etc). As anyone who has ever had a general anesthetic will attest, when the anesthetic is given, the shutters close and blackness descends for a fraction of a second, then you're not even aware of the blackness, not the passage of time, and suddenly, you're coming round and consciousness returns.

Taken together these show that consciousness is an emergent property of neurophysiology, in other words, it's a manifestation of the material world of chemistry and physics; a complex manifestation but materialist, nonetheless.

Creationists, of course, need to try to force-fit their superstition of a magic 'soul' thing living inside them because that's what they like to think is them and will live on when their body dies. So, they can't afford to admit that mind and body can't be dissociated and consciousness depends on a fully functioning neurophysiology, or that death is the ultimate and irreversible loss of consciousness, when neurophysiology stops.

And now a team of neuroscientists at the Massachusetts Institute of Technology (MIT) have discovered more about how a particular anesthetic, Propofol, acts on the brain to produce unconsciousness (a lack of consciousness). They found that it blocks the actions of certain neurotransmitters - which is entirely consistent with the materialist view of consciousness as a property of neurophysiology.

In binding to receptors in the brain, Propofol appears to disrupt the fine balance between excitability and chaos. The brain needs to be excitable enough to receive new stimuli, but not so excitable that its processes become chaotic. There is a brief increase in excitability when a stimulus is received, but this normally quickly falls back to the ground state as a feedback mechanism asserts control. Propofol seems to slow this return to the ground state.

In other words, consciousness is not an emergence of order out of chaos, but an emergence from the order that is imposed on potential chaos. Allowing the balance to shift too far towards chaos results in a loss of consciousness.

The team's findings are explained in an open access paper in Neuron and in an MIT news release:

Study reveals how an anesthesia drug induces unconsciousness

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Propofol, a drug commonly used for general anesthesia, derails the brain’s normal balance between stability and excitability.

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There are many drugs that anesthesiologists can use to induce unconsciousness in patients. Exactly how these drugs cause the brain to lose consciousness has been a longstanding question, but MIT neuroscientists have now answered that question for one commonly used anesthesia drug.

Using a novel technique for analyzing neuron activity, the researchers discovered that the drug propofol induces unconsciousness by disrupting the brain’s normal balance between stability and excitability. The drug causes brain activity to become increasingly unstable, until the brain loses consciousness.

The brain has to operate on this knife’s edge between excitability and chaos. It’s got to be excitable enough for its neurons to influence one another, but if it gets too excitable, it spins off into chaos. Propofol seems to disrupt the mechanisms that keep the brain in that narrow operating range.

Professor Earl K. Miller, co-corresponding author
The Picower Institute for Learning and Memory
Massachusetts Institute of Technology, Cambridge, MA, USA.

The new findings, reported today in Neuron, could help researchers develop better tools for monitoring patients as they undergo general anesthesia.

Miller and Ila Fiete, a professor of brain and cognitive sciences, the director of the K. Lisa Yang Integrative Computational Neuroscience Center (ICoN), and a member of MIT’s McGovern Institute for Brain Research, are the senior authors of the new study. MIT graduate student Adam Eisen and MIT postdoc Leo Kozachkov are the lead authors of the paper.

Losing consciousness

Propofol is a drug that binds to GABA receptors in the brain, inhibiting neurons that have those receptors. Other anesthesia drugs act on different types of receptors, and the mechanism for how all of these drugs produce unconsciousness is not fully understood.

Miller, Fiete, and their students hypothesized that propofol, and possibly other anesthesia drugs, interfere with a brain state known as “dynamic stability.” In this state, neurons have enough excitability to respond to new input, but the brain is able to quickly regain control and prevent them from becoming overly excited.

Previous studies of how anesthesia drugs affect this balance have found conflicting results: Some suggested that during anesthesia, the brain shifts toward becoming too stable and unresponsive, which leads to loss of consciousness. Others found that the brain becomes too excitable, leading to a chaotic state that results in unconsciousness.

Part of the reason for these conflicting results is that it has been difficult to accurately measure dynamic stability in the brain. Measuring dynamic stability as consciousness is lost would help researchers determine if unconsciousness results from too much stability or too little stability.

In this study, the researchers analyzed electrical recordings made in the brains of animals that received propofol over an hour-long period, during which they gradually lost consciousness. The recordings were made in four areas of the brain that are involved in vision, sound processing, spatial awareness, and executive function.

These recordings covered only a tiny fraction of the brain’s overall activity, so to overcome that, the researchers used a technique called delay embedding. This technique allows researchers to characterize dynamical systems from limited measurements by augmenting each measurement with measurements that were recorded previously.

Using this method, the researchers were able to quantify how the brain responds to sensory inputs, such as sounds, or to spontaneous perturbations of neural activity.

In the normal, awake state, neural activity spikes after any input, then returns to its baseline activity level. However, once propofol dosing began, the brain started taking longer to return to its baseline after these inputs, remaining in an overly excited state. This effect became more and more pronounced until the animals lost consciousness.

This suggests that propofol’s inhibition of neuron activity leads to escalating instability, which causes the brain to lose consciousness, the researchers say.

Better anesthesia control

To see if they could replicate this effect in a computational model, the researchers created a simple neural network. When they increased the inhibition of certain nodes in the network, as propofol does in the brain, network activity became destabilized, similar to the unstable activity the researchers saw in the brains of animals that received propofol.

We looked at a simple circuit model of interconnected neurons, and when we turned up inhibition in that, we saw a destabilization. So, one of the things we’re suggesting is that an increase in inhibition can generate instability, and that is subsequently tied to loss of consciousness.

Adam J. Eisen, co-lead author
The Picower Institute for Learning and Memory
Massachusetts Institute of Technology, Cambridge, MA, USA.

This paradoxical effect, in which boosting inhibition destabilizes the network rather than silencing or stabilizing it, occurs because of disinhibition. When propofol boosts the inhibitory drive, this drive inhibits other inhibitory neurons, and the result is an overall increase in brain activity.

Ila R. Fiete, co-corresponding author
McGovern Institute for Brain Research
Massachusetts Institute of Technology, Cambridge, MA, USA.

The researchers suspect that other anesthetic drugs, which act on different types of neurons and receptors, may converge on the same effect through different mechanisms — a possibility that they are now exploring.

If this turns out to be true, it could be helpful to the researchers’ ongoing efforts to develop ways to more precisely control the level of anesthesia that a patient is experiencing. These systems, which Miller is working on with Emery Brown, the Edward Hood Taplin Professor of Medical Engineering at MIT, work by measuring the brain’s dynamics and then adjusting drug dosages accordingly, in real-time.

If you find common mechanisms at work across different anesthetics, you can make them all safer by tweaking a few knobs, instead of having to develop safety protocols for all the different anesthetics one at a time. You don’t want a different system for every anesthetic they’re going to use in the operating room. You want one that’ll do it all.

Professor Earl K. Miller

The researchers also plan to apply their technique for measuring dynamic stability to other brain states, including neuropsychiatric disorders.

This method is pretty powerful, and I think it’s going to be very exciting to apply it to different brain states, different types of anesthetics, and also other neuropsychiatric conditions like depression and schizophrenia.

Ila R. Fiete

The research was funded by the Office of Naval Research, the National Institute of Mental Health, the National Institute of Neurological Disorders and Stroke, the National Science Foundation Directorate for Computer and Information Science and Engineering, the Simons Center for the Social Brain, the Simons Collaboration on the Global Brain, the JPB Foundation, the McGovern Institute, and the Picower Institute.

Highlights

• We developed DeLASE, a method for quantifying changes in neural stability
• During propofol-induced unconsciousness, neural activity was destabilized
• Destabilized artificial systems had similar dynamics to the destabilized brain
• Increasing inhibition, as propofol does, destabilized artificial network activity

Summary
Every day, hundreds of thousands of people undergo general anesthesia. One hypothesis is that anesthesia disrupts dynamic stability—the ability of the brain to balance excitability with the need to be stable and controllable. To test this hypothesis, we developed a method for quantifying changes in population-level dynamic stability in complex systems: delayed linear analysis for stability estimation (DeLASE). Propofol was used to transition animals between the awake state and anesthetized unconsciousness. DeLASE was applied to macaque cortex local field potentials (LFPs). We found that neural dynamics were more unstable in unconsciousness compared with the awake state. Cortical trajectories mirrored predictions from destabilized linear systems. We mimicked the effect of propofol in simulated neural networks by increasing inhibitory tone. This in turn destabilized the networks, as observed in the neural data. Our results suggest that anesthesia disrupts dynamical stability that is required for consciousness.

Graphical abstract

Introduction
The pharmacological action and neurophysiological response of propofol are well understood, but how it renders unconsciousness is not. Propofol boosts inhibition through GABAA (γ-aminobutyric acid type A) receptors and significantly alters cortical dynamics.^1,2,3,4,5,6 This could disrupt the cortical communication on which consciousness depends,^1,2,7 but the exact link to theories of consciousness is not clear. Many theories of consciousness have focused on the representation and network structure involved in integrating information or linking together cortical representations.^{8,9,10,11,12,13,14} For example, one prominent theory of consciousness posits that awareness follows from an “ignition” that produces widespread cortical spiking, much like a few claps can lead to a whole audience applauding.^10,15,16 However, overly excitable and unstable states are uncontrollable, indicative of pathological conditions.^17,18 Thus, we hypothesize that a key factor in consciousness is dynamic stability. Brain states should be sufficiently excitable for generation of widespread activity and information integration. But they also need to be controllable and stable, reliably producing the same computations.^{19,20,21,22,23}

Stability has long been known to be critical for brain function, but early computational work investigated it in the context of convergence to a single state, involving a kind of “freezing” of neural activity.^24,25,26 However, normal neural activity is rarely so stationary; rather, it constantly evolves through dynamic trajectories.^27,28 Thus, stability, and hence consciousness, needs to be understood in terms of a dynamic brain.^21,22 Here, we approach the analysis of anesthetic unconsciousness through the lens of dynamic stability (henceforth stability) (Figure 1A), a fundamental concept in dynamical systems theory and control. Essentially, dynamic stability is a measure of the robustness of a dynamical system. The system needs to be able to recover from disturbances (e.g., distractions, random fluctuations in activity) to its normal state.

Figure 1 Introduction: Stability and instability, and hypothesis candidates

1. (Left, top) Depiction of stability in dynamics: starting from two distinct initial conditions, system trajectories converge. (Left, bottom) Diagram of a stable system—a pendulum with friction—that will converge to the bottom position regardless of the starting point. (Right, top) Depiction of instability in dynamics: starting from two similar initial conditions, system trajectories diverge to distinct paths. (Right, bottom) Cartoon of an unstable system—the weather—where a small perturbation, like a butterfly’s wings flapping, may cause a large-scale change such as a tornado.²⁹
2. Three hypotheses regarding the impact of propofol anesthesia on neural dynamics: dynamics can be more unstable, more stable, or show no significant change compared with awake dynamics.
3. Sample neural data from the propofol dataset: (top row) LFPs during the awake (left) and unconscious (right) states. (Bottom row) Spike rasters during awake (left) and unconscious (right) states. In the awake state, LFP signals are lower amplitude with higher-frequency activity, and spiking is consistent without coordinated bursting. In the unconscious state, LFP signals display low frequency, hypothesized to underlie loss of consciousness.^1,2 Spiking during the unconscious state shows up-state/down-state bursting patterns.

Previous work on cortical stability during anesthesia has produced contradictory results, suggesting that anesthesia either destabilizes^30,31 or excessively stabilizes^32,33,34 neural dynamics (Figure 1B). This could be due to a paucity of studies using high-density intracortical electrophysiology and the inability to therefore apply sufficiently rich dynamical tools to assess stability. Thus, we used a dataset of local field potential (LFP) recordings with hundreds of electrodes from multiple brain regions in two non-human primates (NHPs, specifically adult rhesus macaque monkeys) as they lost and regained consciousness due to propofol anesthesia (Figure 1C).

We introduce a new approach—delayed linear analysis for stability estimation (DeLASE). DeLASE directly quantifies changes in stability in neural data. We show that this method produces high-quality models of nonlinear circuit dynamics while maintaining the simplicity and tractability of a linear dynamical system. We validated the model’s estimates of changes in dynamic stability in systems for which the ground truth stability is known. We found that propofol-induced unconsciousness is associated with destabilized neural dynamics.

Eisen, Adam J.; Kozachkov, Leo; Bastos, André M.; Donoghue, Jacob A.; Mahnke, Meredith K.; Brincat, Scott L.; Chandra, Sarthak; Tauber, John; Brown, Emery N.; Fiete, Ila R.; Miller, Earl K. Propofol anesthesia destabilizes neural dynamics across cortex Neuron 2024; 10.1016/j.neuron.2024.06.011

Copyright: © 2024 The authors.
Published by Cell Press. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)

Despite the evidence such as this that consciousness can be abolished with chemicals, creationists will still maintain that it exists separate from the brain and is god-magic rather than the product of neurophysiology. To admit otherwise would entail a fundamental reassessment of their core superstition that they have a magic self living inside their body which death releases to enjoy eternal life (or unspeakable torture, depending on whether you've said the right magic words at the right time or not, but not on how you've live your life or behaved towards others).

Since religion is for people who been made afraid of death by childhood indoctrination, this is too much for them to contemplate.

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