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Lessons Learned from Haitian Voodoo: Zombification and the Altered Consciousness Experience

nasabere's picture

Lessons Learned from Haitian Voodoo: Zombification and the Altered Consciousness Experience


That which constitutes consciousness is among the most ancient of unsolved mysteries and proves to be a perpetual source of intellectual conundrum. How can the totality of the conscious experience arise from the activities of “salt flowing through channels?” So much of what constitutes the flux of daily life evades our awareness; one might reasonably conjecture that consciousness is but an extraneous commodity. If this is the case, why did evolution select against a state of “zombification”— a dependable network of central pattern generators that produce reliably consistent outputs to any given input? What survival value is attached to a conscious life? What is its function—or rather, does it have any functional value at all? The phenomena of altered states of consciousness, specifically “zombification,” provide a unique avenue with which to explore all of the aforementioned questions surrounding the nature of consciousness. I delve into the realm of unconsciousness in hopes that its scrutiny will reveal possible misconceptions regarding the nature of consciousness.

What is meant by the term “altered state of consciousness?” Anthropologist Erika Bourguignon employs a rather comprehensive definition in her book entitled Religion, Altered State of Consciousness, and Social Change:




 “Altered states of consciousness are conditions in which sensations, perceptions, cognition, and emotions are altered. They are characterized by changes in sensing, perceiving, thinking, and feeling. They modify the relation of the individual to self, body, sense of identity, and the environment of time, space, or other people. They are induced by modifying sensory input, either directly by increasing or decreasing stimulation or alertness, or indirectly by affecting the pathways of the sensory input by somatopsychological factors. As a result, the rules of perception and cognition that cross-cultural psychology has been investigating . . . do not necessarily apply to these states" (1)


Thus, it is in this light I wish to understand “zombification—” first in a Haitian sense, and then in a purely philosophical sense.

 The Haitian voodoo tradition describes the zombie as an individual who possesses the “spirit of a dead person—a being who lacks a “conscious” life, a sense of agency, and the states of sentience, feeling, and awareness, associated with “typical” human functioning. (2) According to Haitian folklore, the magical powers of a bokor, or sorcerer, forces its victims into a state of subservience in which the zombie must act out the wishes of the person controlling her/him. Take the example of Clairvius Narcisse (3)—the man who sparked a series of scientific inquiries regarding the legendary voodoo phenomenon of zombiism. His story starts in the Albert Shweitzer Hospital, an American-run institution in Deschapelles, Haiti, where medical records revealed that he was declared dead in 1962. Oddly enough, more than 200 people recognized him after his “reappearance,” many of which alleged that he was working as a slave on a sugar plantation. Psychiatrist Dr. Lamarque Douyon and Harvard ethnobiologist Dr. Wade Davis were intrigued by such rumors and soon ventured to Haiti in pursuit of scientific explanation for the “zombie” phenomenon. They hypothesized that Narcisse had been poisoned in such a way that his vital signs could not be detected by unsophisticated medical instruments; thus the chase began for said chemical agent. Douyon obtained a sample mixture of toad skin and puffer fish from a local bokur, which was later found to contain a coma-inducing neurotoxin called tetrodotoxin that induced many of the symptoms of zombiism.

Arne Dietrich hypothesizes in Functional Neuroanatomy of Altered States of Consciousness: The Transient Hypofrontality Hypothesis (4), that a unifying factor in all altered states of consciousness— daydreaming, hypnosis, various drug-induced states, coma/vegetative states, and dissociative identity disorders to name a few— are principally due to transient prefrontal cortex deregulation. The evidence she presents suggests that the prefrontal cortex exerts inhibitory control over inappropriate or maladaptive emotional and cognitive behaviors. This tendency was evidenced in 1983 in examining patients that lacked a fully functional frontal lobe. Such patients were “overly dependent on immediate cues”; they tended to act impulsively on what they saw without acknowledging a grander scheme. In addition, the patients examined showed a strong tendency to imitate inappropriate behaviors modeled by others. Researchers then surmised that without a fully functional frontal lobe, the subject could only utilize immediate cues and failed to select behaviors based on more universal principles (4). Such data suggests implicates the frontal lobe as grounds for cognitive flexibility or to borrow Dietrich’s words, “it releases us from the slavery of direct environmental triggers.”

Can this help us in understanding the zombie phenomenon? Perhaps. The compound tetrodotoxin is said to act via inhibiting voltage gated sodium channels. Perhaps such channels are specific to regions in the brain that modulate consciousness (frontal lobe or the “neuronal correlates of consciousness”, as will be discussed later). This, however, is just mere speculation and is only one of many theories surrounding the Haitian zombie phenomonen. Other approaches have implicated schizophrenia, psychogenic amnesia, catonia, or other psychological disorders as a multitude of possible Western diagnoses that could fit that which is described as a “zombie.”

Now for a look at zombification in a more philosophical sense: Christof Koch calls into question what he terms neurological “zombie agents” in his book The Quest for Consciousness: A Neurobiological Approach (5). He points out that, a disconcertingly large proportion of our everyday activities maintain remnants of these so called “zombies” and that we complete much of life in “autopilot mode” in much the same way that a theoretical zombie might do so; brushing our teeth, making the bed, blinking, chewing, dancing, are all among such activitiesEssentially, any sufficiently well rehearsed activity is the product of the nervous system on autopilot mode—what we termed in class to be the work of central pattern generators. In a fiercely competitive world, consciousness must provide us with some sort of an edge over a zombie.

To address this issue, Koch offers the following hypothesis: “if you happen to be an organism with plenty of input sensors and output effectors—say a mammal—devoting a zombie system to each and every possible input-output combination becomes [energetically] expensiveInstead, evolution chose a different path, evolving a powerful and flexible system whose primary responsibility is to deal with the unexpected and to plan for the future.” (5) He surmises that consciousness evolved as a means to provide an “executive summary” of the world around us—a mechanism to selectively filter out the overload of information in the nervous system and focus on a concise summary of the relevant facts in order to be more efficient beings. Thus, perhaps it can then be inferred that awareness occurs at the interface between processing and planning—wherever that may be—the latter of which the theoretical zombie is incapable of achieving. Koch also goes on to discuss what is called the “Neuronal Correlate of Consciousness:” this theory suggests that there exist special sets of "consciousness" neurons distributed throughout cortex. Activity of an appropriate subset of these neurons is both necessary and sufficient to give rise to an appropriate conscious experience or percept (5).

So what can the zombie—in its state of altered consciousness—reveal to us about the nature of what it means to be conscious? First, that it may have a physical, tangible component that manifests itself in the nervous system as evidenced by its ability to be altered via neurotoxic agents (tetrodotoxin). Second— a zombie lives within even the “conscious,” healthy individual.  Third—even the theoretical zombie is not in a state of total and complete unconsciousness; the notion of the hypothetical zombie is impossible in principle, because in order for it to be truly unconscious, it must not be able to interact with the outside world. Even theoretical zombies have perceptual experience and the like and thus they exhibit "behavior."  Perhaps the greatest misconception regarding consciousness is the notion that it is distinctly different from unconsciousness. Is it truly necessary that we differentiate between the two states? Could central pattern generators be behind the entirety of the human experience—conscious and not?  Perhaps consciousness is but an illusion; we know that the mind certainly plays tricks on us; maybe the notion of consciousness is but its grandest and most profound.


1. Mental Unity, Altered States of Consciousness, and Dissociation

2. Zombie Encyclopedia

3. Time Magazine: Do Zombies Exist?

4. Functional Neuroanatomy of Altered States of Consciousness: The Transient Hypofrontality Hypothesis

5. The Quest for Consciousness: A Neurobiological Approach

6. Interview with Koch

7. Consciousness



Paul Grobstein's picture

what zombies can and cannot do ...

Yes, I think this is a useful way to begin thinking about consciousness (or, perhaps better, the I-function?). And I think you were almost there, before you switched to "Perhaps consciousness is but an illusion". I suspect there is indeed an illusion here but also a function. It isn't "to interact with the outside world" (that doesn't require consciousness) but perhaps to "plan for the future", indeed perhaps even to conceive of a future?