Synchrony in neural and visceral systems: a bioelectric basis of consciousness

Abstract

The Default Space Theory (DST) of consciousness claims that consciousness arises from bioelectric oscillations across brain and body which become time-locked to form an internal three-dimensionalized “default space” which continuously simulates external reality. Within this frame, we assert that fast rhythms created corticothalamically with the thalamic reticular nucleus (TRN) can become time-locked with regions throughout the brain via nascent oscillations as well as sensory organs and viscera. This proposed time-locking may render exteroceptive and interoceptive processed information one in the same as conscious experience. We review/integrate salient neuroscientific and physiological findings that validate DST. We reveal findings across the last decoding of the theory's detailed components from corticothalamic feedback loops to lateral/inhibition dynamics, from descending efferent projections to sensory organs. We utilize high cervical cord injury (HCCI) as syndromically supporting/denying DST's postulates regarding the necessity of bodily input to consciousness. Finally, we compare/contrast theories (Global Workspace, Integrated Information Theory, Predictive Processing) with DST to reveal overlaps/distinctions within theoretical scaffolds. At its heart, the DST is an all-encompassing biological apparatus through which typical oscillations create a “functional unity” of consciousness. Yet developments within the DST have brought about clarity that simultaneous connected long distances (i.e., gamma oscillations aligning cortex to sensory receptors) is a theory to be born out of experimentation, not reality. There is indirect support from visual studies for retinal rhythmic activity driving thalamocortical firing in a way consistent with modulation but direct phase-locking of periphery receptors with gamma activity in the cortex is aspirational, not reality. In addition, we corrected a prior disconnection regarding motor representations: focus of outputs occurs by surround inhibition (SI) eliminating superfluous irrelevant activations, not the cortical silent period—thus when SI fails there is motor “overflow.” We further clarify the importance of viscera in conscious experience with several examples: spontaneous breathing aligns electrical oscillations in limbo circuits, heart beats are shown to engage/disengage cortical activity and awareness, gastric slow waves correlate in-phase with what occurs in somatosensory and visual domains. All support DST positing that the neural and visceral systems operate as one oscillator network which, together, support consciousness. In an HCCI patient where somatic input below the neck is deceased, however, they experience retained consciousness, however. This DST predicts because oscillations of the head/brain and rhythms from the viscera allow continuity of internal space; yet its content/persona changes because the body map has been temporally truncated. This provides a distinction about how people can be consciously aware of their existence while feeling completely different at the same time—there is a core conscious sense vs. the schemas decorating it over timescales. The DST provides a bioelectric understanding of consciousness which connects brain-body-environment. Where we emphasize where theoretical estimations lie vs. what can be observed supports the DST. For example, if one excessively disrupts corticothalamic feedback loops or sensorimotor oscillations and fails to integrate things into consciousness, DST is supported. Conversely, these stimulus distortions will never come from any other theoretical premise. Prominent notions are shared with Global Workspace or Integrated Information-based systems regarding global integration, but no other theory has included the body's oscillatory components as part of consciousness; contrary to predictive processing, while prediction errors determine hypotheses, DST puts forward simultaneous synchronization as critical and afferent/efferent dynamics physicalized two-way brain-body communication. Testing factors inevitable in evolution include consistent electrophysiological studies with descending pathways, works decoding states of consciousness in paralysis. All citations updated for relevancy—new studies incorporated—non-self-citations limited to remove experimenter's bias—all to urge ongoing discourse between DST and contemporaneous science of consciousness research.