Unmasking the Hidden Protagonist in the Theater of Consciousness
We all want to know what lies at the heart of our very existence. Throughout our lives, we are part of a constantly changing drama that manifests itself in an enormous variety of conscious experiences which are phenomenal in nature. These subjective, phenomenal experiences include both stimulus-induced conscious perceptions and stimulus-independent mental states. The findings of neuroscience leave no doubt that the brain plays an important role in this drama. However, the question remains as to whether the brain is really starring in the Theater of Consciousness or whether we have so far overlooked the main actor that is hiding in the background. What actor could this be and how do we manage to unmask this actor?
To organize the search for the hidden protagonist as systematically as possible, it is advisable to gather all the information that neuroscience can provide about the structural organization of the brain and the dynamical features of conscious processes. After that, it is necessary to examine these findings for telltale signs that give us clues to the existence of the player acting in the background. This step also includes the development of models and the performance of model calculations that allow us to simulate the player’s behavior and compare it with the telltale traces. In other words, we make assumptions about the player’s profile and use the available data to assess whether the assumed profile matches the clues. Step by step, we thus arrive at a wanted poster that provides us with many details about the true character of the suspect. These details ultimately help us to develop strategies for unmasking the suspect.
So, let’s embark on an exciting quest and start with the empirical findings on the neural correlates of consciousness (NCC). A substantial body of evidence suggests that conscious states are related to synchronized neural activity patterns extending across distributed cortical areas. In-depth data analyses reveal that pattern formation takes place as an abrupt transition from a disordered phase to an ordered phase in which a large number of neurons exhibit collective behavior. This is why we refer to a phase transition in this context. A decisive function in triggering phase transitions falls to the neurotransmitters, whose concentrations serve as control parameters. The excitatory neurotransmitter glutamate, which (apart from water) has by far the highest concentration in neural tissue, deserves special mention here.
The dynamical characteristics of brain activity do not only depend on molecular components but also on the design principles underlying brain architecture, with our primary focus being on the structural organization of the cortex. There is ample evidence that the microcolumn constitutes the basic functional unit of which all cortical areas are composed. A typical microcolumn has a diameter of approximately 30 μm and contains roughly 100 neurons, mainly pyramidal neurons. In simplified terms, a microcolumn can be thought of as a bunch of pyramidal neurons enclosed in a glutamate pool. The microcolumns are strongly interconnected with each other as well as with subcortical structures, especially the thalamus.
The finding that phase transitions are involved in the formation of conscious states enables us to take up the hidden player’s trail. It is known from physics that the origin of phase transitions can best be understood within the framework of quantum field theory, which has turned out to be remarkably powerful in describing collective behavior in many-body systems. Since the dominant interaction in the brain is the electromagnetic interaction, we arrive at quantum electrodynamics (QED) as the starting point for our further tracking. The self-consistent formulation of QED presupposes the existence of an ever-present ocean of energy, implying that the vacuum is not a void, but a vibrant sea filled with ceaseless activity. These ubiquitous, random vacuum fluctuations are also known as electromagnetic zero-point field (ZPF). In physical terms, the ZPF is represented by a spectrum of normal modes, with each ZPF mode being characterized by a specific frequency.
The combination of clues leads us to the idea of formulating a QED-based model of a microcolumn and exploring the interaction of the glutamate pool with the ZPF in greater detail. The model calculations show that upon reaching a critical coupling strength of the glutamate pool to the ZPF, a phase transition is initiated. In a microcolumn, this condition is fulfilled when a critical glutamate concentration is exceeded, caused by the release of highly concentrated glutamate from numerous synaptic vesicles of the pyramidal neurons. Under this condition, resonant glutamate-ZPF coupling is established, in which the frequency of the ZPF modes involved is equal to the frequency of the preferred vibrational excitation of the glutamate molecules (in the terahertz range). Now, the crucial point is that resonant glutamate-ZPF interaction gives rise to a situation in which the amplitude of the dynamically relevant ZPF modes is significantly boosted and the glutamate pool switches to a collective, coherent state. Accordingly, we are dealing here with macroscopic quantum coherence, resulting in the formation of a coherence domain.
Our QED-based model thus offers us illuminating insights into the process of a phase transition, summarized in the following figure.
The trace we are following therefore looks promising. An important initial finding is that, according to the model calculations, the neurotransmitter concentration in synaptic vesicles has exactly the right level to trigger a phase transition. But the model delivers much more. When it comes to the extent of a coherence domain, the calculations yield a value of 30 μm, which is in excellent agreement with the measured diameter of a microcolumn. Moreover, we find that a coherence domain is shielded by a considerable energy gap, which is an essential prerequisite for isolating the collective state from thermal perturbations. The model calculations thus demonstrate the plausibility of macroscopic quantum phenomena under the wet and warm conditions encountered in the brain. And finally, the emergence of a coherence domain turns out to be responsible for downstream effects that are decisive for the communication between microcolumns and their synchronization.
All these findings are explained in detail in the following publication: A field-theoretical model of cortical dynamics.
What conclusions can be drawn from these findings about the NCC? Clearly, our model indicates that long-range synchronization in the brain emerges through a bottom-up orchestration process involving the ZPF, a key characteristic of this process being the formation and synchronization of coherence domains. This dynamical process encompasses all levels of brain organization: the glutamate-ZPF interaction takes place at the microscopic level, leading to the establishment of coherence domains at the mesoscopic level, where coherence-driven downstream effects occur that regulate the macroscopic behavior of the system. Control over this process can be achieved by varying the proportion of activated synapses. Each synchronized activity pattern in the brain is thus characterized by a specific assembly of microcolumns in which the criticality condition is fulfilled.
By revealing these mechanisms, we have not only gained a deeper understanding of the neurodynamics associated with conscious processes but have also obtained valuable pointers to the actor that is operating in disguise. This actor is the ZPF, which we had not previously recognized. Is the ZPF even the hidden protagonist in the Theater of Consciousness? And if so, how does this actor manage to bring phenomenal qualities onto the stage?
To answer these questions, it is worth recalling that the ZPF plays an integral role in the fabric of the universe and that the resonant interaction between the brain and the ZPF results in the amplification of specific (dynamically relevant) ZPF modes. Let us now assume that the ubiquitous ZPF is endowed not only with extrinsic, energetic properties, but also with intrinsic, phenomenal qualities. In this case, each particular mode in the frequency spectrum of the ZPF represents a particular phenomenal shade. We call this the hypothesis of the dual-aspect ZPF. From this perspective, the random ground state of the ZPF, in which no modes are amplified and singled out from other modes, can be interpreted to mean that the universe is imbued with an undifferentiated background of consciousness. Proceeding from this interpretation, the significance of the brain-ZPF interaction mechanism for the formation of concrete conscious states now becomes obvious: The amplification of specific ZPF modes is inextricably linked with the excitation of specific phenomenal qualities. In other words, resonant brain-ZPF coupling explains how a concrete conscious state emerges from the undifferentiated background of consciousness. This theory of consciousness, according to which phenomenal states arise through resonant amplification of zero-point modes, is given the acronym TRAZE.
The scientific basis of TRAZE is set out in the following publication: Laying the foundations for a theory of consciousness.
In contrast to theories that rely on a neural substrate of consciousness, TRAZE offers a mechanism that not only explains the dynamical characteristics observed in brain processes associated with consciousness, but also provides a conclusive explanation for the formation of phenomenal states. According to TRAZE, the neural activity patterns constituting the NCC should not be regarded as the ultimate basis of consciousness but are to be seen as macroscopic manifestations of a functional principle underlying conscious systems whose roots lie at a deeper level. This leads to a paradigm shift from a neural substrate of consciousness to a universal substrate of consciousness that can be accessed under suitable conditions. The accumulated body of evidence therefore suggests the following scenario: The universal substrate of consciousness is the ZPF, and access to consciousness is restricted to those systems that are capable of coupling to the ZPF, with the brain-specific implementation of the coupling mechanism being based on the modulation of neurotransmitter concentrations.
But let’s be cautious. The dual-aspect hypothesis, according to which the ZPF has intrinsic phenomenal qualities, has yet to be empirically tested. The central idea behind this test is to influence the structure of the ZPF in such a way that those ZPF modes that are essential for the integrity of the coupling mechanism are selectively eliminated. Such a manipulation can be performed locally in a small array of microcolumns. By excluding the relevant ZPF modes, resonant coupling of the glutamate pool to the ZPF cannot establish, causing the functional breakdown of the affected microcolumns. The prediction is that this breakdown entails the absence of phenomenal states usually experienced. First-person accounts can be used to validate the expected absence of conscious experiences. It is crucial to note that in this test setup only the local structure of the ZPF is manipulated, without making any changes to the brain. In this way, the design of the experiment is specifically tailored to demonstrate that phenomenal awareness is a phenomenon that does not emerge from the brain. An affirmative test result would provide clarity and irrevocably unmask the hidden protagonist in the Theater of Consciousness.
