A zombie (Haitian Creole: zonbi) can be either a fictional undead monster or a person in an entranced state believed to be controlled by a bokor or wizard. These latter are the original zombies, occurring in the West African Vodun religion and its American offshoots Haitian Vodouand New Orleans Voodoo.

Zombies became a popular device in modern horror fiction, largely because of the success ofGeorge A. Romero\'s 1968 film Night of the Living Dead^[1] and they have appeared as plot devices in various books, films and in television shows. Zombie fiction is now a sizeable sub-genre of horror, usually describing a breakdown of civilization occurring when most of the population become flesh-eating zombies – a zombie apocalypse. The monsters are usually hungry for human flesh, often specifically brains. Sometimes they are victims of a fictionalpandemic illness causing the dead to reanimate or the living to behave this way, but often no cause is given in the story.

West African Vodun

According to the tenets of Vodou, a dead person can be revived by a bokor, or sorcerer. Zombies remain under the control of the bokor since they have no will of their own. "Zombi" is also another name of the Vodou snake lwa Damballah Wedo, of Niger-Congo origin; it is akin to theKikongo word nzambi, which means "god". There also exists within the West African Vodun tradition the zombi astral, which is a part of the human soul that is captured by a bokor and used to enhance the bokor\'s power. The zombi astral is typically kept inside a bottle which the bokor can sell to clients for luck, healing or business success. It is believed that after a time God will take the soul back and so the zombi is a temporary spiritual entity.^[2] It is also said in vodou legend, that feeding a zombie salt will make it return to the grave.

Several decades later, Wade Davis, a Harvard ethnobotanist, presented a pharmacological case for zombies in two books, The Serpent and the Rainbow (1985) and Passage of Darkness: The Ethnobiology of the Haitian Zombie (1988). Davis traveled to Haiti in 1982 and, as a result of his investigations, claimed that a living person can be turned into a zombie by two special powders being entered into the blood stream (usually via a wound). The first, coup de poudre (French: \'powder strike\'), includes tetrodotoxin (TTX), a powerful and frequently fatal neurotoxin found in the flesh of the pufferfish (order Tetraodontidae). The second powder consists of dissociative drugs such as datura. Together, these powders were said to induce a death-like state in which the will of the victim would be entirely subjected to that of the bokor. Davis also popularized the story of Clairvius Narcisse, who was claimed to have succumbed to this practice.

The process described by Davis was an initial state of death-like suspended animation, followed by re-awakening—typically after being buried—into a psychotic state. The psychosis induced by the drug and psychological trauma was hypothesised by Davis to re-inforce culturally-learned beliefs and causing the individual to reconstruct their identity as that of a zombie, since they \'knew\' they were dead, and had no other role to play in the Haitian society. Societal reinforcement of the belief was hypothesized by Davis to confirm for the zombie individual the zombie state, and such individuals were known to hang around in graveyards, exhibiting attitudes of low affect. In 1988, Wes Craven, directorof the Nightmare on Elm Street horror series of movies, filmed The Serpent and the Rainbow, which diverges significantly from the book.

Davis\' claim has been criticized, particularly the suggestion that Haitian witch doctors can keep “zombies” in a state of pharmacologically induced trance for many years.^[4] Symptoms of TTX poisoning range from numbness and nausea to paralysis (particularly of the muscles of the diaphragm), unconsciousness, and death, but do not include a stiffened gait or a death-like trance. According to psychologist Terence Hines, the scientific community dismisses tetrodotoxin as the cause of this state, and Davis\'s assessment of the nature of the reports of Haitian zombies is viewed as overly credulous.