Scientific Understanding of Consciousness
Consciousness as an Emergent Property of Thalamocortical Activity


In Search of a Biological Basis for Consciousness

By William Oates Covington, Jr.

What Is Consciousness?

What is it about our brain that allows us to experience the ‘me’?  What is in our heads that gives each of us the unique individuality through which we experience our life? Philosophers and theologians have expounded on this subject for millennia, but only recently has science advanced to the point of offering some potential insights.


A little More Discussion of ‘What is Consciousness’


Science is beginning to Offer Some Insights

During the past 20 years or so, biological sciences have advanced to the point that scientists have begun researching biological mechanisms of brain function and suggesting some reasonably well-founded hypotheses for consciousness. Leading the way in these pioneering efforts, in my judgment, have been:


Gerald Edelman with his hypothesis of the Dynamic Core,    Edelman obit from Nature.

Antonio Damasio with his concepts of  Protoself, Core Self, Autobiographical Self, Core Consciousness and Extended Consciousness,

Joseph LeDoux and his emphasis on the intricacies of synapses and the emotional brain,

Rudolfo Llinás and his researches into ~40 Hz oscillations and synchronization,

György Buzsáki with his discussion and exploration of neural mechanisms related to oscillation and synchronization in the neocortex and hippocampus for perception and memory,

Joaquín Fuster, the world’s preeminent expert on the frontal lobes, and his concept of the "perception-action cycle,"

Susan Greenfield's notion of "neuronal gestalts" as a way of conceptualizing a highly variable aggregation of neurons that is temporarily recruited around a triggering epicenter. I use the neuronal gestalts idea in my way of visualizing the functionality of the dynamic core of the thalamocortical system,

Eric Kandel who has explored short-term and long-term memory,

The late Francis Crick with his collaborator Christof Koch who have pursued the neural correlate of consciousness (NCC),

Michael Gazzaniga with the concept of the left hemisphere ‘interpreter’ unifying consciousness experience,

Edmund Rolls and Gustavo Deco with their mathematical models of brain function using information theory approaches for biologically plausible neurodynamical modeling of cognitive phenomena corroborated by brain imaging studies,

David LaBerge with his discussion of the thalamocortical circuit and attention,

Alan Baddeley who continues to refine his model for working memory,

Philosopher John Searle who endorses the idea that consciousness is an emergent property of neural networks.

Ongoing current work is continually reported in the journals Science and Nature and the PLoS (Public Library of Science) website.  I include paraphrases of hundreds of these articles, which provide a sampling of significant recent developments. Diffusion magnetic resonance imaging is beginning to provide much insight into the brain’s neural network. Researching the mouse cerebral cortex will provide fundamental biological information applicable to the human neural network. NIH has funded a Human Connectome Project (HCP) to map the brain's long-distance communications network. The Obama administration is planning a decade-long scientific effort to examine the workings of the human brain and build a comprehensive Brain Activity Map. A further discussion of the Brain Activity Map Project Proposal. Recent work in the Human Brain Model Ultrahigh-Resolution. Current status of President Obama’s Neurotechnologies (BRAIN) Initiative. Redirection of the European Human Brain Project.


Link to — Brain Observatory Proposal


Numerous other scientists have both expanded and consolidated a number of thoughts such as these. A little more comment on the Experts.


These and other scientists that I refer to in this website are world renowned, many with the Nobel Prize. They can certainly speak with authority on topics of science.

This website contains discussions and links to paraphrases I have generated from books authored by consciousness experts. I have used more than 120 reference books from which I show nearly 20,000 paraphrases. I have included hundreds of the paraphrases within the topics discussions. I have also included hundreds of paraphrases of recent information from Science, Nature, PLoS.

My objective in this website has been to bring together salient features of these assorted interpretations by science experts into a synthesis of my own understanding of consciousness. I consider these statements and interpretations to be a framework on which to build a fuller understanding as further data, concepts and insights develop from ongoing research.










Introduction -- The science of consciousness is continuing to develop among the experts. To gain an understanding of their current thinking, I think it helps to have a number of expositions even if they sometimes seem redundant.  So in this website, I'll have some pages that are short and to a specific point, others that are longer and offer a little more detail, and still others in which I have collected paraphrases from a number of experts. You’ll notice that the last part of some web pages have not yet been well edited.

Synopsis of My Understanding of Consciousness – a brief bullet list of my understanding. Read this section first. I provide a statement of the major points of consciousness that is consistent with most experts but without specific references.

Covington Theory of Consciousness —  compendium of my current understanding of consciousness.

Major Concepts of Consciousness – Here is a list of the concepts you should be aware of when you begin a scientific discussion of consciousness.

Reentry and Recursion a Continuing Theme

A continuing theme is reentry and recursion in an unstructured hierarchical neural networks, with perhaps ~20 ms cycle in visual sensory cortex, ~50 ms cycle in perception association cortex, and >1 sec cycle in prefrontal decision cortex. These continuously-operating asynchronous local neuronal assemblies aggregate via the associative property of memory into the ever-changing sparse but widespread neural assemblies of the dynamic core of consciousness.

Esoteric Terms and Concepts – Brief explanations (alphabetized list) of terms often used in discussions of consciousness. In a number of instances researchers have adopted common words for a specialized technical meaning. Also, researchers often have their own ad hoc terms for similar concepts; in most cases I have selected one of these terms. In a few cases, I have coined my own term to avoid the confusion of multiple terms for nearly identical concepts.




Subject Outline table of contents with Links to Topic Discussions.

‘Scatter of Topics’ Diagrams

Topics Links Chart – another way of Linking to Topics Discussions -- pictorial diagrams providing links to the consciousness topics discussed

Index of Topics Discussed – Here is an alphabetical list of topics discussed

I believe the neural researches of autism spectrum disorder provide one way to gain further insight into the workings of the neural network.

Challenge of Music and Cognition – How can neuronal circuitry that provides the auditory perception and logical inference functions for language also provide the emotional experience of music?

Sidebar Discussions — Paraphrases of recent articles from Science, Nature, PLoS along with further discussion of selected topics. Here is a computer formatted list of Sidebars. (It may take a few moments)

PLoS Biology Selections — Links to articles I judged to be interesting and informative for Consciousness


Modeling the Brain Functionality of Consciousness – As scientists continue to gain an understanding of the biological basis of consciousness, it will be imperative to have a model of brain functionality (somewhat analogous to the Standard Model of particle physics), in which scientists can add their concepts and results and have them subjected to further corroboration. This section shows some early pioneering attempts to gain an understanding of consciousness through models.

Human-type Consciousness — leap immediately into consciousness discussion

Future Developments and Concepts Current theories of the experts don't always interface perfectly.  I'll speculate on ways in which I think further research could improve the interfaces between expert’s theories, leading to a more unified theory of neural functionality for consciousness.

[still under construction]



My Background Qualifications to Understand Science

I am William Oates Covington, Jr., a retired engineer with a graduate degree in engineering from MIT and a career that included work with the guidance computer of the Apollo manned lunar landing program and with broadband communications network computer simulation at the former Bell Telephone Laboratories. I have the scientific background to understand technical material, including statistical analyses, graphically presented results, and the meaning and relationships of physical phenomena. During twenty years of retirement I have spent countless hours reading and studying the weekly journals Science and Nature, along with published books by experts and internet source material on the topics of evolution, cell biology, human genome sequencing, embryonic development, functions of enzymes, kinases, signaling cascades, cell surface receptors, neurotransmitters, etc.

My background is sufficient to read and understand the gist of writings by science experts. I will also add a few of my own interpolations and an occasional extrapolation


Reference Book Paraphrases From more than 120 reference books, I have selected and show more than 20,000 paraphrase extracts.

I also show a webpage of Samples of the Book References Paraphrases.


Book References List – includes links to descriptions and reader commentary for the book references.



Please send your comments on the scientific understanding of the biological basis of human consciousness to





Link to — Consciousness Subject Outline

Further discussion — Covington Theory of Consciousness

Text Box: This site is a work in progress.
More changes to come.