Zombies continue their multi-decade popularity as subject matter for horror films and cultural commentary. AMC’s series The Walking Dead is one of the most acclaimed shows on TV. I talked about how zombies capture people’s attention in my post Marketing in the Uncanny Valley. Now it’s time to explore zombification in real life. Fortunately, humans have greater memory recall when faced by zombies (PMID: 21327372). And we have math!
Reanimating the dead isn’t possible at the moment, but simulating death may be possible. Most medical attention has involved the use of tetrodotoxin, a neurotoxin that supposedly puts humans into a state of suspended animation. This was popularized by Dr. Wade Davis, an ethnobotanist who pursued wacky escapades in the Caribbean. He discussed his findings in a paper titled “The Ethnobiology of the Haitian Zombie” (PMID: 6668953). The paper’s title was also used for the subtitle of a book by Dr. Davis, Passage of Darkness, which was overshadowed by his more popular book The Serpent and the Rainbow.
Other researchers analyzed the traditional Haitian zombification powder and confirmed that it contained tetrodotoxin (PMID: 2728032). However, an article in the Skeptical Inquirer magazine (which I found from the Wikipedia entry on tetrodotoxin) expresses skepticism regarding its use as a zombification agent. Zombies are probably just misidentified wandering mentally ill persons, as reported by a study in The Lancet (PDF). A very recent study published in the journal Evidence-Based and Complementary and Alternative Medicine discusses the Haitian preparation and uses it as the basis for a discussion of zootherapy (PMID: 21977054).
Patients taking certain medications or experiencing an illness sometimes use the term “zombie” to report how they feel or describe their worries. Here are some examples. Some of these studies are very sad, especially the ones that discuss children who feel or act like zombies.
• Patients with neuroleptic induced deficit syndrome (PMID: 7652089)
• Patients experiencing anesthesia awareness (PMID: 18635380)
• Patients with postoperative cognitive dysfunction (PMID: 19396043)
• An emotional state in patients with borderline personality disorder (PMID: 10616128)
• Heart transplant patients who felt like zombies (PMID: 1299462)
• Adolescents with cancer (PMID: 15681977)
• A child with developmental delay who exhibited “zombie-like” behaviors (PMID: 20414073)
Also, a study of schizophrenia medication mentioned an interesting hypothesis. The researcher feared that the medication would turn patients into zombies. Fortunately, those fears were unfounded. (PMID: 7244281)
The popular sleep drug zolpidem sometimes leads to zombie-like behaviors such as sleep eating (PMID: 20529770), sleep emailing (PMID: 19059805), sleep sex (PMID: 18998740), and even sleep driving (PMID: 21367628) without conscious awareness. Interestingly, zolpidem can also somewhat reanimate patients who are in a persistent vegetative state (PMID: 16720934). An overdose can put people in a coma, but it may also bring people out of a vegetative state. It’s important to note that this arousal from a comatose state may only be temporary and doesn’t necessarily occur in all patients. Zolpidem still may be the best zombie drug we have at the moment. Maybe it should have been called Zombien.
Cellular activities are also discussed in terms of zombies:
• A loci for mutations (PMID: 9007229)
• Zombie transposable elements in plant genomes (PMID: 21444239)
• Neurons in Alzheimer’s disease becoming zombies (PMID: 21479393)
Parasitology and entomology offer interesting studies about how organisms can be controlled by other organisms. Here are some examples:
• Fungal infections control the behavior of ants and lead them toward their doom (PMID: 21554670)
• There are multiple species of brain-manipulating fungus (PMID: 21399679)
• Hornet queens may use pheromones to turn workers into zombies (PMID: 10849289)
• A wasp uses a neurotoxin to manipulate the nervous system of a cockroach, turning it into a “zombie” (PMID: 20383324)
• The manipulative wasp leads to speculation on the nature of free will (PMID: 21057640)
There’s also the ever-popular toxoplasma gondii brain parasite, which reduces fear in rats and makes them sexually attracted to things they were once afraid of (PMID: 21858053)