Consciousness, the brain, and spacetime geometry.
(1)Department of Anesthesiology and Psychology, Center for Consciousness and its relation to the fundamental theory of matter--as described by quantum theory. until a mass-time-energy threshold (related to quantum gravity) is reached. Universe consists of three fundamental entities — space-time, matter and con- The relationship between a consciousness and its brain has traditionally been. Time is not a fundamental physical reality like matter, energy and physical space. Time exists only when we measure it; time is a mind model.
One can see such strategically purposive behaviour in both single celled protists such as paramecium and in active human cells such as neutrophils hunting and consuming bacteria Kingfig 3.
Consequently the major neuroreceptor classes have a very ancient origin, with the 5HT1 and 5HT2 families diverging before the molluscs, arthropods and vertebrates diverged, close to the level of the founding metazoa.
Sponges, with only two cell types, express serotonin Wayrer et al. Coelenterates already have all the key components of serotonin pathways, involved in signalling by sensory cells and neurons, despite having only a primitive nerve network McCauley et al. The metabotropic protein-activating glutamate and GABA receptors likewise go back to the social amoeba Dictyostelium discoideum, where there is a family of 17 GABA receptors and a glutamate receptor involved in differentiation Taniura et al The glutamate-binding fly trap section of both ionotropic and metabotropic glutamate receptors show homologies with the bacterial periplasmic amino-acid binding protein Felder et alOh et alLampinen et al These changes are already in place in the cyanobacterial ionotropic glutamate receptor.
The fact that an iGluR has also been found in Arabidopsis Turano et al shows this class entered the eucaryotes before the plants, animals and fungi diverged. Elements of the protein signalling pathways, such as protein kinase C, essential to neuronal synaptic contact originated close to the eucaryote origin Emes et al.
Likewise the Dlg family of postsynaptic scaffold proteins, which bind neurotransmitter receptors and enzymes into signaling complexes originated before the divergence of the vertebrates and arthropods Nithianantharajah et al. Thus we can see how the survival modalities of complex organisms have continued to be mediated by classes of neurotransmitters modulating key motivational, aversive and social dynamics, from single cells to multi-celled organisms, with ascending central nervous system complexity.
There are thus strong parallels in how the key classes of neurotransmitters modulate affect in organisms as diverse as arthropods and vertebrates. In higher animals, 5-HT continues in its role as a homeostatic regulator in adjusting the dynamic interactions of these many functions within the organism, and how the organism interacts with the outside world, elaborated in humans into a variety of functions including the sleep-wakefulness cycle, triggering the psychedelic state, depression and social delinquency King Similarly, dopamine and nor-epinephrine pathways modulate reward and vigilance, forming a spectrum of fundamental strategic responses in humans, including motor coordination roles whose overstimulation or disruption can lead to Parkinsons, dependency and psychosis.
Reports of increased social dominance in primates Edwards and Kravitz, and improved mood and confidence in social interactions in humans after using drugs which increase serotonin levels are well documented Kramer, ; Young and Leyton, Serotonin in lobsters regulates socially relevant behaviours such as dominance-type posture, offensive tail flicks, and escape responses Kravitz,Sosa et al. In insects, dopamine acts instead as a punishment signal and is necessary to form aversive memories Barron et al.
In flies dopamine modulates locomotor activity, sexual function and the response to cocaine, nicotine, and alcohol Hearn et al. Octopamine, the arthropod analogue of norepinephrine, regulates desensitization of sensory inputs, arousal, initiation, and maintenance of various rhythmic behaviors and complex behaviors such as learning and memory, and endocrine gland activity Farooqui Web building in spiders is likewise affected by stimulants and psychedelics Dunn.
These neurotransmitters are thus playing a similar role in humans in modulating the excitable brain to attune it to survival objectives that these same signalling molecules had in single celled eucaryote social and reproductive behaviours.
Moreover, although most neurophysiological investigations of arthropod and mollusc neural ganglia tend to be recordings of single neuronal action potentials e. These results lead us to the hypothesis that there is a common basis of attentive processing in the gamma band across wide branches of the metazoa, based on edge-of-chaos processing and wave phase coherence, despite their highly varied neuroanatomies Basar et al.
In the face of the apparent causality of the Laplacian universe, many 20th century philosophers assigned to consciousness the orphan status of an epiphenomenon, a mere reflection of physical reality which could have no influence upon it. Some, such as Gilbert Rylewho coined the term "the ghost in the machine", went further, attempting to deconstruct the dualistic notion of mind altogether, as a form of false reasoning, claiming "that the idea of Mind as an independent entity, inhabiting and governing the body, should be rejected as a redundant piece of literalism carried over from the era before the biological sciences became established.
The proper function of Mind-body language, he suggests, is to describe how higher organisms such as humans demonstrate resourcefulness, strategy, the ability to abstract and hypothesize and so on from the evidences of their behaviour".Are Space and Time An Illusion? - Space Time - PBS Digital Studios
Derived from the dualistic cosmology of Rene Descartes, the subjective arena of conscious awareness is frequently referred to as the "Cartesian theatre", sometimes constructively, as in Barrswho describes the theatre of the conscious in terms of working memory and its associated backdrops, but other times in somewhat disparaging terms as in Dennett's Consciousness Explainedwho, rather than explaining consciousness, as he claims, replaces it with a "multiple drafts model", more representative of the publishing industry, than either the conscious mind, or the sentient brain, a work critics have said should have been entitled "Consciousness Ignored".
Running counter to the reduction of consciousness to a combination of deterministic laws and utterly random perturbations, are approaches in which consciousness is seen as somehow fundamental to the existential condition, complementary to physical phenomena and processes.
The nature of this complementarity in contrast to attempts on the part of functionalists to finesse consciousness to be merely an aspect of the attention process, or certain classes of excitation, such as those in the gamma range of the electroencephalogram, or EEG Hzhave been highlighted in David Chalmers' enunciation of the so-called "Hard Problem" in consciousness research, - "explaining why we have qualitative phenomenal experiences".
It is contrasted with the "easy problems" of explaining the ability to discriminate, integrate information, report mental states, focus attention, etc. Easy problems are easy because all that is required for their solution is to specify a mechanism that can perform the function. For example Crick and Koch identify conscious states accompanying attentive processes with higher frequency EEG signals in the gamma range.
The dilemma of the hard problem implies that no purely objective mechanism can suffice to explain subjective consciousness as a phenomenon in its own right. This leads ultimately to a cosmology in which consciousness and the physical universe are complementary.
The organization of the cerebral cortex and its underlying structures, consist of a series of microcolumns vertically spanning the three to six layers of the cortex, acting as parallel processing units for an envelope of characteristics, a hologram-like featural mathematical transform space.
Typical features represented in particular cortical regions include sensory attributes such as the line orientation and binocular dominance of visual processing, tonotopic processing of sounds, somato-sensory bodily maps, and higher level features such as facial expressions and the faces of individuals, leading to the strategic executive modules of the prefrontal cortex and our life aims and thought processes.
The many-to-many nature of synaptic connections forms the basis of this abstract representation, which is also adaptive through neural plasticity.
Space and time also become features in the transform mapping, so that certain e. The hippocampus pivotal in consolidating sequential memory also appears to function as a spatial GPS, emphasizing the mutual relation between space and time in transform space see fig4E. A key role of wave-based brain processing is to harness this transform representation to predict, using experiential memory and contextual clues, the ongoing nature of opportunities and threats to survival. Existential reality presents as a complementary paradox.
While we acknowledge our subjective consciousness is somehow a product of our biological brain, which is in turn a fragile product of physical forces on a cosmological scale, all our experiences of reality, including our perceptions of the physical world, as well as dreams memories and reflections, come exclusively and totally from our subjective consciousness.
This suggests that existential cosmology is a complementarity between subjective consciousness and the physical universe, in which both are fundamental.
In the veridical way existential reality is generated, subjective experience is primary. In the consensual overlap of our subjective experiences we gain a common experience of the physical world, which we then interpret as containing biological brains, which may also be able to have subjective experiences.
However, attempted construction of reality from the physical universe and its brains remains incomplete because there is no explanation of how the brains can also have subjective conscious experiences - the hard problem of consciousness research. Regions in the saliency circuit. Common regions involved in the self, the default network and alert consciousness. Regions in the self network Zimmer The default network Fox Subjective consciousness involves coordinated whole-brain activity Baars, as opposed to local activations, which reach only the subconscious level, as evidenced in both experiments on conscious processing and the effects of dissociative anaesthetics Alkire et al.
Attempts to find the functional locus of subjective consciousness in brain regions have arrived at the conclusion that active conscious experiences are not generated in a specific cortical region but are a product of integrated coherent activity of global cortical dynamics Ananthaswamy This distributed view of conscious brain activity is consistent with experimental studies in which the cortical modules we see activated in fMRI and PET scans correspond to salient features of subjective conscious experience.
This implies that the so-called Cartesian theatre of consciousness is a product of the entire active cortex and that the particular form of phase coherent, edge-of-chaos processing adopted by the mammalian brain is responsible for the manifestation of subjective experience. This allows for a theory of consciousness in which preconscious processing e.
Several lines of research have highlighted the idea of the present moment encapsulated in brain function in terms of processes which extend over short periods of time enabling a sustained observation of anticipated events binding together functional and experiential moments of seconds duration, which are subsequently bound into memory, a concept first enunciated by Augustine WittmanFairhall et al. The approach is also consistent with there being broadly only one dominant stream of conscious thought and experience at a given time, as diverse forms of local processing give way to an integrated global response.
A series of experiments involving "inattentional blindness" Thakral - perceptual masking of brief stimuli to inhibit their entry into conscious perception Sergent et al.
EEG studies also show that under diverse anesthetics, as consciousness fades, there is a loss of synchrony between different areas of the cortex Alkire et al. The theory also tallies with Tononis idea of phi, a function of integrated complexity used as a measure of consciousness BarrasPagel Two opposing global attention systems have been identified, one the dorsal attention network deals with focal attention in the global workspace and is bilateral connecting areas such as the frontal eye fields to parietal and other areas.
The Relationship between Consciousness of Self and Perception of Time
Complementing this is the ventral attention network whose role is to bring in salient stimuli, important to the subject, from the periphery. Intriguingly this has lateralized activity in the right cortex, complementing the left hemisphere regions traditionally associated with language, lending support to the above model of lateralization.
A third system sometimes called the salience network Seeley et al. It may also be associated with intentional will Parvizi et al. Brain regions involved in our sense of self - the actor-agent behind conscious states - are also specifically activated in idle periods, when the salience and attention networks become inactive, the so-called default network, whose function appears to be adaptively envisaging future challenges.
The ventral medial prefrontal Macrae et al. It also plays a role in the inhibition of emotional responses, and decision-making. It has been shown to be active when experimental subjects are shown imagery they think apply to themselves.
The insulae are also believed to be involved in consciousness and play a role in diverse functions usually linked to emotion and the regulation of the body's homeostasis, including perception, motor control, self-awareness, cognitive functioning, and interpersonal experience. The anterior insula is activated in subjects who are shown pictures of their own faces, or who are identifying their own memories. The temporo-parietal junction is known to play a crucial role in self-other distinction and theory of mind.
Studies indicate that the temporo-parietal junction has altered function during simulated out of body experiences Ananthaswamy Although subjective consciousness involves the entire cortex in coherent activation, brain scans highlight certain areas of pivotal importance, whose disruption can impede active consciousness. Another set of two regions, anterior cingulate and fronto-insular are highlighted in the saliency circuit Williams in which von Economo VEN bipolar neurons provide fast connectivity between regions to maintain a sense of the conscious present providing a sense of immediate anticipation of the ongoing external and internal condition saliency and interoception.
These appear prominently in large brained animals, including humans, elephants and cetaceans where there is greater need to rapidly stitch together related processing areas critical to the ongoing conscious state. Several researchers have highlighted specific aspects of consciousness in an attempt to understand how it evolved. Higher integrative processing associated with global workspace has been extended to other animals such as apes and dolphins Wilson Another approach suggests that making integrative decisions socially would have aided better environmental decision-making concerning hard to discern situations involving the combined senses in which social discussion aids survival, such as two hunters trying to assess whether dust on the prairie suggests running from lions or hunting buffalo, or women discussing where to find hard to get herbs from the visual appearance, taste and smell of a sample Bahrami et al.
The claustrum has wide-ranging neural connections and has also been implicated in reversible disruption of consciousness when stimulated Koubeissi et al. Conscious Survival in the Wild To discover what advantage subjective consciousness has over purely computational processing, we need to examine the survival situations that are pivotal to organisms in the open environment and the sorts of computational dilemmas involved in decision-making processes on which survival depends.
Many open environment problems of survival are computationally intractable and would leave a digital antelope stranded at the crossroads until pounced upon by a predator, because they involve a number n of factors, which increase super-exponentially with n.
For example, in the traveling salesman problem - finding the shortest path around n cities - the calculation time grows super-exponentially with the factorial n-1! There are probabilistic methods which can give a sub-optimal answer and artificial neural nets solve the problem in parallel by simulating a synaptic potential energy landscape, using thermodynamic annealing to find a local minimum not too far from the global one. Vertebrate brains appear to use edge of chaos dynamics to similar effect.
Open environment problems are intractable both because they fall into this broad class and also because they are prone to irresolvable structural instabilities, which defy a stable probabilistic outcome. Suppose a gazelle is trying to get to the waterhole along various paths. On a probability basis it is bound to choose the path, which, from its past experience, it perceives to be the least likely to have a predator, i.
But the predator is likewise going to make a probabilistic calculation to choose the path that the prey is most likely to be on given these factors i.
- Consciousness, the brain, and spacetime geometry.
Ultimately this is an unstable problem that has no consistent computational solution. This context shows active anticipation in social contexts in a single species another situation in which individual survival in a social community is at stake is driven by specific neural circuits devoted to social "future prediction".
Foreboding prescience is key when a young shark lunges at a gull, which faces it head on squawking and then manages to escape in the nick of time when it lunges again at speed. Decision-making in the open environment involves computationally intractable problems, which cannot necessarily be solved by probabilities alone.
Space, Time and Consciousness
We nominate a quantum computational OR process with the requisite characteristics to be occurring in cytoskeletal micro-tubules within the brain's neurons. In this model, quantum-superposed states develop in microtubule subunit proteins "tubulins" within certain brain neurons, remain coherent, and recruit more superposed tubulins until a mass-time-energy threshold related to quantum gravity is reached. At that point, self-collapse, or objective reduction ORabruptly occurs.
We equate the pre-reduction, coherent superposition "quantum computing" phase with pre-conscious processes, and each instantaneous and non-computable OR, or self-collapse, with a discrete conscious event. Sequences of OR events give rise to a "stream" of consciousness. Microtubule-associated proteins can "tune" the quantum oscillations of the coherent superposed states; the OR is thus self-organized, or "orchestrated" "Orch OR".
The quantum gravity threshold for self-collapse is relevant to consciousness, according to our arguments, because macroscopic superposed quantum states each have their own spacetime geometries. These geometries are also superposed, and in some way "separated," but when sufficiently separated, the superposition of spacetime geometries becomes significantly unstable and reduces to a single universe state. Quantum gravity determines the limits of the instability; we contend that the actual choice of state made by Nature is non-computable.
Thus each Orch OR event is a self-selection of spacetime geometry, coupled to the brain through microtubules and other biomolecules.