Fact Checking Scott Alexander’s Discussion of Julian Jaynes’s Theory on “Slate Star Codex” – Part 2

By Marcel Kuijsten

In June 2020, the psychiatrist and blogger Scott Alexander wrote a review of Julian Jaynes’s The Origin of Consciousness in the Breakdown of the Bicameral Mind for his popular “Slate Star Codex” blog. His discussion of Jaynes’s theory contains a number of misconceptions and errors, and I will attempt to clear those up here. While the first three sections of his review are more or less just a summary of Jaynes’s main arguments and some topics he feels are related or supportive, the issues I’d like to address can be found in the fourth and fifth sections of his post.

Misunderstanding Jaynes’s Definition of Consciousness

Alexander asks the question: “Did he [Jaynes] literally believe that the Sumerians, Homeric Greeks, etc. were p-zombies? … I cannot be completely sure.” P-consciousness is a “type of consciousness,” according to the philosopher Ned Block, the “P” standing for “phenomenal.” It roughly equates to what Jaynes would more accurately call “awareness” or “sensory perception” — the world you perceive when you open your eyes. Block contrasts this with A- or “access” consciousness, which is more closely related to Jaynes’s definition of an introspectable mind-space. To wonder whether or not Jaynes believed that the ancient Sumerians and other ancient cultures lack “p-consciousness” is simply a gross misunderstanding of the theory, and readers that are unclear on this point would do well to re-read the first two chapters of Jaynes’s book, as well as the Afterword. Surprisingly, this same error was also made by Ned Block in his 1977 review of Jaynes’s book. This misconception, along with other misconceptions by Ned Block, are exhaustively addressed by the philosophy professor Jan Sleutels in his article “Greek Zombies,” which appeared in Philosophical Psychology and was updated and revised for the book Reflections on the Dawn of Consciousness. Professor Sleutels also clarifies these issues in his interview in Conversations on Consciousness and the Bicameral Mind.

To be clear, all animal life, including insects, has the experience of sensory perception, to widely varying degrees. This would of course include early, even pre-bicameral humans. Even microorganisms have fairly complex methods of navigating their environment, and habituate to stimuli in their surroundings (Lazova, 2011). But the experience of sensory perception — of sights, smells, sounds and colors — should not be confused with consciousness, because (among other reasons), much of what organisms (including humans) perceive and respond to happens nonconsciously, as Jaynes goes to great lengths to explain. We are consciously aware of only a small fraction of what we perceive (Kilhstrom, 1987; Nørretranders, 1991). Jaynes revisits this topic in the Afterword of his book (added to the 1990 and later editions):

Perception is sensing a stimulus and responding appropriately. And this can happen on a nonconscious level, as I have tried to describe in driving a car. Another way to look at the problem is to remember the behavior of white blood cells, which certainly perceive bacteria and respond appropriately by devouring them. To equate consciousness with perception is thus tantamount to saying that we have six thousand conscious entities per cubic millimeter of blood whirling around in our circulatory system — which I think is a reductio ad absurdum.

(Julian Jaynes, The Origin of Consciousness in the Breakdown of the Bicameral Mind, p. 448-449)

To try to make the distinction even clearer, infants of course have “wakefulness,” “awareness,” and sensory perception, but according to Jaynes — as well as Dennett (2005), Zelazo (1999, 2007), and others — they do not yet possess what we might call “Jaynesian” consciousness (others use the term “self-consciousness”), which develops as they learn metaphorical language. Similarly, a person with advanced dementia will likely see a diminishment of some or all of the features of Jaynesian consciousness, but of course still have “wakefulness,” “awareness,” and sense perception. Conversely, Jaynesian consciousness — “an analog ‘I’ narratizing in a mind-space” — can now be observed in some individuals that are in a vegetative state, who are shown to be able to visualize themselves playing tennis, or moving around their home, “in a manner indistinguishable from that of healthy volunteers” (Owen, 2006).

A prominent psychology professor often states that infants are more conscious than adults. In constructing this argument, the professor could just as easily have made the case that cats are more conscious than adults (or a variety of other non-human animals), because what is primarily being described are changes in attention — not consciousness. The fact that many theorists confuse consciousness with things like sense perception, wakefulness, awareness, and attention, or use the term “consciousness” in other vague, poorly defined ways, does not make it correct. In non-human animals (or pre-conscious humans), “sentience” is a better term for what is often referred to as consciousness.

Alexander also states that Jaynes seems to be “unaware of (or avoiding)” the “hard problem of consciousness.” However, that phrase was coined by David Chalmers in 1995 — 18 years after Jaynes’s book was published (in January of 1977), and two years before Jaynes’s death. As just discussed, Jaynes would likely have viewed this as the problem of the experience of sensory perception. To put it another way, it was not the issue he was primarily concerned with, which was the origin of our ability to introspect, to have what he called “an analog ‘I’ narratizing in a mind-space.” As a side-note, the philosopher Daniel Dennett — whose views on consciousness in certain ways are similar to Jaynes’s — has argued persuasively that in fact there is no “hard problem of consciousness” (Dennett, 2018).

Jaynesian Consciousness Is Not the Same As “Theory of Mind”

Next Alexander suggests that what Jaynes really identified was that the ancient Greeks and people in other cultures prior to 1500 B.C. simply lacked “theory of mind” — or a knowledge that other people have an inner mental life that differs from their own. However consciousness — as defined by Jaynes — and theory of mind are two completely different things. What Jaynes carefully documents, through a variety of different lines of evidence, is the lack of subjective interiority or “inner mind-space” in ancient cultures, as well as a previous “bicameral” mentality. In ancient Greece, the emergence of consciousness ushers in a “cognitive explosion,” and we see the beginnings of history, science, philosophy, and theater. Follow-up research has documented the transition from bicameral mentality to consciousness in cultures that Jaynes did not investigate, such as ancient China (Carr, 2006) and ancient Tibet (Gibson, 2016, 2022). The transition is also documented in the changing nature of dreams — from “visitation” to conscious (Atwan, 2016; Jaynes, 2012a; Kuijsten, 2022). We see a similar transition to consciousness through language development in children (Rowe, 2016, 2022; Zelazo, 1999, 2007). This is not simply the failure to recognize mental states different than our own in others (“theory of mind”).

At best we can say that theory of mind is a feature (or perhaps a sub-feature) of Jaynesian consciousness, and, as such, theory of mind tests are also perhaps one of the means by which we can measure consciousness, in child development, for example. Jaynes lists the features of consciousness on pages 59-65 and 449-452 of his book, and it is a much more extensive set of skills than simply possessing theory of mind. The changes Jaynes documents in ancient history are also more profound. For an in-depth discussion of why Jaynesian consciousness should not be confused with theory of mind, please see my interview with psychology professor John Kihlstrom in Conversations on Consciousness and the Bicameral Mind (published after Alexander’s blog post), and Jaynes’s own brief commentary on this issue in The Julian Jaynes Collection (Jaynes, 2012b).

But why does Alexander propose that Jaynes identified the origin of “theory of mind,” rather than the origin of consciousness, in the first place? Alexander’s primary source of confusion — as is unfortunately so often the case with confusion about Jaynes’s theory — seems to stem from a failure to understand how narrowly and precisely Jaynes defines consciousness. It seems he did not do a careful reading of this section of Jaynes’s book, and he is likely (and perhaps unknowingly) substituting his own, broad (and vague) definition of consciousness for Jaynes’s very narrow, precise definition. While this may be a bit of informed speculation on my part, whenever people fail to grasp Jaynes’s narrow definition of consciousness, it generally leads to all of the predictable, “Ned Block-style” objections. Alexander’s own definition of consciousness has to be inferred, however, because — as is so often the case — he never explains his own definition of the term. His attempts to critique Jaynes’s arguments, then, seem to be based on a broad definition of consciousness that Jaynes would never have agreed with. The kinds of things that many writers and theorists often lump under the umbrella term of “consciousness,” Jaynes more accurately relegates to things like reactivity, sense perception, learning, and cognition. It often takes multiple readings of Jaynes, as well as periods of reflecting on his ideas, to fully grasp his arguments.

Alexander then turns his attention to Jaynes’s discussion of bicameral mentality and Jaynes’s neurological model for bicameral mentality. He states:

I am not an expert in functional neuroanatomy, but my impression is that recent research has not been kind to any theories too reliant on hemispheric lateralization.

What follows are some examples of Alexander’s misunderstandings and mischaracterizations of Jaynes’s arguments on these topics — and, more specifically, mischaracterizations of the new evidence for Jaynes’s arguments — along with brief clarifications.

Confusion on Split-Brain Research

Alexander contends that findings of the split-brain experiments by Sperry, Gazzaniga, and Bogen “[don’t] replicate.” Here he is referring to the evidence from research on split-brain patients that suggests that, when the primary connection between the brain hemispheres is severed, the two hemispheres seem to operate much more independently, to the extent that two separate “spheres of consciousness,” one per hemisphere, seem to emerge. To back up his sweeping claim that findings from decades of research on this subject have somehow been refuted, he cites a Science Daily press release (University of Amsterdam, 2017) referring to research by the Dutch neuroscientist Yair Pinto (2017).

It is rare that a single study ever refutes the findings of decades of research on any subject, and in this instance, it certainly does not. The fact of the matter is that Yair Pinto is a well known skeptic of some of the conclusions of split-brain research — one might go so far as to say that he is something of a “split-brain research conclusions denier.” And while there is certainly nothing wrong with raising thoughtful objections to scientific research — indeed, that is a critical part of the scientific process — in my view, his arguments against the primary findings of split-brain research, although at times thought-provoking, don’t hold up to serious scrutiny or debate.

The fact is that many of the key findings from the split-brain experiments, as bizarre and provocative as they may be, have actually held up quite well (Gazzaniga, 2005). For an outstanding recent discussion of this research and its philosophical implications, see philosophy professor Elizabeth Schechter’s Self-Consciousness and “Split” Brains: The Minds’ I (2018). I highly recommend reading this book (while expensive, it can be obtained via inter-library loan), and also watching the 2018 debate “Do Split-Brain Patients Have Two Minds?” between Joseph LeDoux, Elizabeth Schechter, and the aforementioned Yair Pinto.

Again, it should be obvious that one article on any subject is rarely definitive, and citing a single article rarely conveys a balanced view of the current state of any controversial or evolving subject matter. You can’t simply dismiss decades of Nobel-prize winning experiments with a wave of the hand, a statement that “they don’t replicate,” and a link to a press release — as Alexander does in his post. (Here I might encourage Dr. Alexander to revisit his own post, “Beware the Man of One Study,” because in at least three places in his commentary on Jaynes, he very much is “the man of one study.”)

How does this research relate to Jaynes’s theory? It demonstrates that, in split-brain patients, the brain hemispheres operate in a more independent, or “bicameral,” manner. It is thus conceivable that this also occurred in the past, but for neuro-cultural (rather than surgical) reasons.

Confusion on the Neurology of Auditory Hallucinations & Jaynes’s Neurological Model

Alexander then makes the statement that

Jaynes says his theory implies that schizophrenic hallucinations come from the language centers of the right hemisphere, and I think the latest fMRI evidence is that they don’t.

Here he is referring to Jaynes’s fourth hypothesis: his neurological model for bicameral mentality, which is that auditory hallucinations emerge in the language areas of the right hemisphere and travel across the corpus callosum, to be “heard” in the language areas of the left hemisphere (in right-handed individuals). On this point, Alexander is simply egregiously wrong.

To support this claim, he again cherry picks one study, while simply ignoring the dozens of studies that provide strong support for Jaynes’s neurological model. Like the study of nutrition, brain science is highly complex, and if one looks hard enough, it’s easy to find a single study to support almost any conclusion. What matters is the preponderance of evidence, and, as we will see, the preponderance of evidence now clearly supports Jaynes’s neurological model.

Alexander does not cite — and appears to not have read — any of the follow-up publications on Jaynes’s theory, as I previously described many of the studies supporting Jaynes’s neurological model in my chapter “Consciousness, Hallucinations, and the Bicameral Mind: Three Decades of New Research” in Reflections on the Dawn of Consciousness (2006) and in an article titled “New Evidence for Jaynes’s Neurological Model: A Research Update” (2007) in The Jaynesian newsletter. Both of these were available for more than a decade before Alexander wrote his blog post, and many of the relevant studies have also been posted in the Summary of Evidence and Supporting Evidence sections of the Julian Jaynes Society website, many also for more than a decade.

More recently — and partly in response to Alexander’s critique — I outlined many of the studies that show clear support for Jaynes’s neurological model in the post: “Neuroscience Confirms Julian Jaynes’s Neurological Model,” as well as in the book Conversations on Consciousness and the Bicameral Mind. I encourage you to take a moment to look at the studies summarized in my post, compare those to the one study Alexander cites (“Tuning in to the Voices: A Multisite fMRI Study of Auditory Hallucinations“), and draw your own conclusions as to whether or not Alexander accurately represents the current state of evidence regarding Jaynes’s neurological model.

It is not at all clear why Alexander cites this one particular study, as the experimental design does not speak as directly to the issue of Jaynes’s neurological model as the many more relevant, better designed studies available — and many of these studies clearly support Jaynes’s early conjectures regarding the bicameral neurology of auditory hallucinations. How could anyone even briefly researching this issue miss, for example, the commentaries by Dr. Robert Olin (“Auditory Hallucinations and the Bicameral Mind,” 1999) and Dr. Leo Sher (“Neuroimaging, Auditory Hallucinations, and the Bicameral Mind,” 2000), both with the full text available online, and both calling attention to Belinda Lennox’s landmark 1999 study, “Spatial and Temporal Mapping of Neural Activity Associated with Auditory Hallucinations” (1999)? Lennox’s fMRI study of a hallucinating schizophrenic patient was the first fMRI study to show strong support for Jaynes’s neurological model. Her findings, or findings roughly similar to hers, have since been replicated by numerous other researchers over the past two decades — including recently.

If you search for “jaynes auditory hallucinations” on Google Scholar, Dr. Olin’s and Dr. Sher’s commentaries are the first and third results. We are left to wonder, 1) did Dr. Alexander not take the short amount of time necessary to locate and read the many more relevant studies that are highly supportive of Jaynes’s neurological model — despite the fact that this would have been very easy to do, or 2) for reasons unknown, did he deliberately mischaracterize the evidence supporting Jaynes’s fourth hypothesis by selecting one ambiguous study while ignoring the many more relevant and more favorable studies? I have no way of knowing, but am willing to give the benefit of the doubt that it was just exceedingly poor research on his part. Either way, he failed to accurately convey the evidence on this subject to his readers.

Confusion on Spirit Possession & the Right Hemisphere

In his book, Jaynes speculates that spirit possession and other trance states might indicate a temporary shift to right-hemisphere dominance. Alexander commits the same “single ambiguous study as definitive evidence” error with regards to Jaynes’s comments on spirit (or demon) possession. He reports one study (Vazquez, 2018) that had ambiguous results regarding right hemisphere activity during the “possessed” state. Yet he fails to mention the many other studies that do support Jaynes’s speculation about right-hemisphere involvement in spirit possession and other trance states. See, for example, Krippner & Combs (2002), Persinger (1993), and Flor-Henry, Shapiro & Sombrun (2016), who state:

We corroborated not only generalized right hemispheric dominance during shamanic trance but also a specific shift from the normative anterior prefrontal to the right posterior mode of awareness.

Once again, it seems that Dr. Alexander did not review all of the relevant research, but instead jumped to conclusions based on a single study, or perhaps looked for a study that seemed to support his pre-existing views. While I would not argue that the evidence for right-hemisphere involvement in trance states is conclusive, I would suggest that it was not accurately portrayed by Dr. Alexander in his post.

Confusion on Preliterate Societies & Vestiges of Bicameral Mentality

In the fifth and final section of his post, Alexander brings up the topic of preliterate societies. Here his misunderstanding of what it means to be a bicameral person (“Jaynes claims Bronze Agers heard gods literally all the time” — Jaynes never suggests this) causes him to question why there isn’t more overt evidence of bicameral mentality documented in preliterate societies. Alexander’s naiveté on the subject is summed up in his somewhat flippant statement that we should expect tribal people to have said things like, “That couple-year period when we all stopped hallucinating gods and became conscious — that was a weird time.”

Psychological transitions in any culture are often gradual, not well documented (if at all), and poorly remembered. Further, there is no reason to believe that some preliterate societies did not develop some of the features of consciousness on their own trajectories. Nonetheless, accounts of recently contacted tribes by Christian missionaries and others are filled with examples of vestigial bicameral practices and behaviors. To give just one example, a missionary reported that:

With these undesirable denizens of the spirit-world … the Ten’a may be said to have an almost continual intercourse” [i.e., communication]. “They hold themselves liable to see or hear them at any time.

Quoted in Lucien Lévy-Bruhl, Primitive Mentality

That sounds a lot like he is describing auditory and visual hallucinations, and one can read many similar examples associated with preliterate societies worldwide. For more examples, see the quotes from books such as Primitive Mentality, How Natives Think, and Do Kamo posted in the “Mentality of Pre-Literate & Pre-Modern Peoples” section of the JJS Forum.

There are many challenges inherent in the study of the psychology and inner mental life of a given individual or culture. For one, anthropologists who studied recently contacted tribes were not familiar with Jaynes’s theory (in most cases, it had not yet been proposed) and were not focused specifically on psychological issues, thus generally they were not asking the relevant questions. A key point to understand, and one that Alexander seems to at least partly acknowledge, is that if you met a bicameral or semi-bicameral person (transported through time) on the street today, it would certainly not be immediately obvious to you. It would take time to develop an understanding of the extent to which their behavior was directed in times of stress by auditory hallucinations, the degree to which they had a well-developed analog ‘I’ narratizing in a mind-space, etc.

Similarly, it would not be immediately obvious to you if you met a conscious person who also frequently hears voices, as many people around the world still do, but rarely discuss. How many people today are aware that a significant percentage of the homeless they pass on the street every day are hearing voices (Desjarlais, 1997)? The fact is, we are surrounded by examples of vestiges of bicameral mentality in modern society — let alone in preliterate societies. Studies by psychologists such as Russell Hurlburt at the University of Nevada, Las Vegas, who for decades has been investigating inner experience (see Hurlburt, 1990, 2011), illustrate both larger than expected differences in the inner dialogue of even modern, conscious people, as well as the challenges inherent in this type of research. The bottom line is that understanding another person’s inner mental life, or lack thereof, is a lengthy, complex process and cannot be immediately gleaned merely from observable behavior.

An exhaustive review of the evidence for bicameral mentality and vestiges of bicameral mentality in recently contacted tribes has yet to be written, but in the meantime, interested readers should look at the source material by Lucien Lévy-Bruhl, Maurice Leenhardt, and other early investigators, as well as more recent investigators such as Daniel Everett (2009).

Summing Up

Scott Alexander’s blog post on Julian Jaynes’s book and theory contains a number of factual errors and significant misunderstandings of Jaynes’s arguments. Furthermore, it fails to mention the great deal of new evidence that supports Jaynes’s theory, instead misleading readers to believe that relevant new studies generally contradict the theory — the opposite of what is true. For those who feel that perhaps I’ve been a bit hard on Dr. Alexander (I have no doubt that he is a well intentioned person), I think it’s important to emphasize that, in my view, bloggers and other writers do their readers a disservice when they publish poorly researched content. By mischaracterizing Jaynes’s theory as essentially not having withstood the test of time — rather than what is in fact the case, that many aspects of Jaynes’s theory are well supported by new evidence — Alexander potentially turned off many of the readers in his large audience to learning more about Jaynes’s fascinating ideas.

Given that Alexander was so out of his depth on this review, and wrong on so many key points, one can only wonder as to the validity of his other posts. The problems seen in Alexander’s post are one of reasons that I’m not a fan of generalist blogs in the first place: authors often seem to feel pressured to constantly churn out new material, and thus are compelled to delve into topics and areas they are wholly unfamiliar with. A better approach is taken by bloggers that stick to their given areas of expertise.

It is my hope that, before writing about Jaynes’s theory, others will see that it is imperative to first familiarize themselves with all (or at least most) of the available literature on the subject, and not just skim Julian Jaynes’s book and think that that now makes them an “expert,” or even in a position to properly evaluate the theory. It is difficult to fully understand all of the nuances of Jaynes’s theory — and impossible to accurately evaluate the evidence for or against it — without also looking at the new evidence, clarifications, and extensions of the theory that have been published in the now more than 45 years since Julian Jaynes first published his book.

I welcome your comments below.

References

Robert Atwan, “The Interpretation of Dreams, The Origin of Consciousness, and the Birth of Tragedy”, in in M. Kuijsten (ed.) Gods, Voices, and the Bicameral Mind (Julian Jaynes Society, 2016).

Michael Carr, “The Shi “Corpse/Personator” Ceremony In Early China,” in M. Kuijsten (ed.) Reflections on the Dawn of Consciousness (Julian Jaynes Society, 2006).

Daniel Dennett, “What Do You Believe Is True Even Though You Cannot Prove It?” Interview for Edge.org, 2005.

Daniel Dennett, “Facing Up to the Hard Question of Consciousness,” Philosophical Transactions of the Royal Society, 2018.

Robert R. Desjarlais, Shelter Blues: Sanity and Selfhood Among the Homeless (University of Pennsylvania Press, 1997).

Daniel Everett, Don’t Sleep, There Are Snakes: Life and Language in the Amazonian Jungle (Vintage, 2009).

Pierre Flor-Henry, Yakov Shapiro & Corine Sombrun, “Brain Changes during a Shamanic Trance: Altered Modes of Consciousness, Hemispheric Laterality, and Systemic Psychobiology,” Cogent Psychology, 2017, 4, 1.

Michael S. Gazzaniga, “Forty-five Years of Split-brain Research and Still Going Strong,” Nature Reviews Neuroscience, 2005, 6, 653–659.

Todd Gibson, “Souls, Gods, Kings, and Mountains: Julian Jaynes’s Theory of the Bicameral Mind in Tibet, Part One” and “Listening for Ancient Voices: Julian Jaynes’s Theory of the Bicameral Mind in Tibet, Part Two,” in M. Kuijsten (ed.) Gods, Voices, and the Bicameral Mind (Julian Jaynes Society, 2016).

Todd Gibson, “Evidence for Bicameral Mentality in Ancient Tibet,” in M. Kuijsten (ed.) Conversations on Consciousness and the Bicameral Mind (Julian Jaynes Society, 2022).

Russell T. Hurlburt, “A Schizophrenic Woman Who Heard Voices of the Gods,” in R. Hurlburt, Sampling Normal and Schizophrenic Inner Experience (Plenum Press, 1990). Reprinted in M. Kuijsten (ed.) Gods, Voices, and the Bicameral Mind (Julian Jaynes Society, 2016).

Russell T. Hurlburt, Investigating Pristine Inner Experience: Moments of Truth (Cambridge University Press, 2011).

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Julian Jaynes, “The Dream of Agamemnon” in M. Kuijsten (ed.) The Julian Jaynes Collection (Julian Jaynes Society, 2012a).

Julian Jaynes, “In A Manner of Speaking: Commentary on Cognition and Consciousness in Non-Human Species,” in M. Kuijsten (ed.) The Julian Jaynes Collection (Julian Jaynes Society, 2012b).

John Kihlstrom, “The Cognitive Unconscious,” Science, 1987, 237, 4821.

S. C. Krippner & A. Combs, “The Neurophenomenology of Shamanism: An Essay Review,” Journal of Consciousness Studies, 2002, 9, 77–82.

Marcel Kuijsten “Consciousness, Hallucinations, and the Bicameral Mind: Three Decades of New Research,” in M. Kuijsten (ed.) Reflections on the Dawn of Consciousness: Julian Jaynes’s Bicameral Mind Theory Revisited (Julian Jaynes Society, 2006).

Marcel Kuijsten, “Consciousness, Language, and Dreams,” in M. Kuijsten (ed.) Conversations on Consciousness and the Bicameral Mind (Julian Jaynes Society, 2022).

Marcel Kuijsten, “New Evidence for Jaynes’s Neurological Model: A Research Update,” The Jaynesian, 2007.

Milena Lazova, et. al., “Response Rescaling in Bacterial Chemotaxis,” Proceedings of the National Academy of Sciences, 2011, 108, 33.

Joseph LeDoux, Yair Pinto, and Elizabeth Schechter, “Debate: Do Split-Brain Patients Have Two Minds?” (NYU Center for Mind, Brain and Consciousness, 2018).

Tor Nørretranders, The User Illusion: Cutting Consciousness Down to Size (Penguin Books, 1991).

Robert Olin, “Auditory Hallucinations and the Bicameral Mind,” The Lancet, 1999, 354, 9173.

Adrian Owen, et al, “Detecting Awareness in the Vegetative State,” Science, 2006, 313, 5792.

Michael A. Persinger, “Vectorial Cerebral Hemisphericity as Differential Sources for the Sensed Presence, Mystical Experiences and Religious Conversions,” Perceptual and Motor Skills, 1993, 76, 915–930.

Yair Pinto, et al. “Split Brain: Divided Perception but Undivided Consciousness,” Brain, January 2017.

Bill Rowe, “Two Origins of Consciousness” in M. Kuijsten (ed.) Gods, Voices, and the Bicameral Mind (Julian Jaynes Society, 2016).

Bill Rowe, “The Development of Consciousness in Children” in M. Kuijsten (ed.) Conversations on Consciousness and the Bicameral Mind (Julian Jaynes Society, 2022).

Elizabeth Schechter’s Self-Consciousness and “Split” Brains: The Minds’ I (Oxford University Press, 2018).

Leo Sher, “Neuroimaging, Auditory Hallucinations, and the Bicameral Mind,” Journal of Psychiatry and Neuroscience, 2000, 25, 3.

Jan Sleutels, “Greek Zombies,” in M. Kuijsten (ed.) Reflections on the Dawn of Consciousness: Julian Jaynes’s Bicameral Mind Theory Revisited (Julian Jaynes Society, 2006).

University of Amsterdam, “Split Brain Does Not Lead to Split Consciousness,” ScienceDaily, January 25, 2017.

Jose Luis Mosso Vazquez, et al., “Resting Stated-Tractography-fMRI in Initial Phase of Spiritual Possession – A Case Report,” Trends in Medicine, 2018.

Philip Zelazo, “Language, Levels of Consciousness, and the Development of Intentional Action,” in P.D. Zelazo, J.W. Astington & D.R. Olson (eds.), Developing Theories of Intention: Social Understanding and Self-Control (Lawrence Erlbaum Associates, 1999).

Philip Zelazo, et al, “The Development of Consciousness,” in P. Zelazo (ed.), The Cambridge Handbook of Consciousness (Cambridge University Press, 2007).

See also: Fact Checking Scott Alexander’s Review of Julian Jaynes’s Theory on “Slate Star Codex” – Part 1, by Brian J. McVeigh

Learn more about Julian Jaynes’s theory by joining the Julian Jaynes Society and reading our books.