The wait has been long, but the discipline of neuroscience has finally delivered a full-length treatment of the zombie phenomenon. In their book, Do Zombies Dream of Undead Sheep?, scientists Timothy Verstynen and Bradley Voytek cover just about everything you might want to know about the brains of the undead. It's all good fun, and if you learn some serious neuroscience along the way, well, that's fine with them, too. Voytek answered questions from contributing editor Gareth Cook.

How is it that you and your co-author came to write a book about zombies? Clearly, it is an urgent public health threat, but I would not have expected a book from neuroscientists on the topic.

Indeed! You think you're prepared for the zombie apocalypse and then—BAM!—it happens, and only then do you realize how poorly prepared you really were. Truly the global concern of our time.

Anyway, this whole silly thing started when Tim and I would get together to watch zombie movies with our wives and friends. Turns out when you get some neuroscientists together to watch zombie movies, after a few beers they start to diagnose them and mentally dissect their brains. Back in the summer of 2010 zombie enthusiast and author—and head of the Zombie Research Society—Matt Mogk got in touch with me to see if we were interested in doing something at the intersection of zombies and neuroscience.

What are some of the things you are able to explain with the help of zombies?

We start with the obvious stuff: Why do zombies move with such a slow, unsteady gait? Why can't they talk? Do they feel pain? We use those obvious questions as stepping-stones toward what we hope is a much more nuanced view of the modern neuroscientific understanding of how the three or so pounds of brain in your head can give rise to the complexities of the human experience. Each chapter tackles a specific behavioral trait relevant to zombies, including movement, hunger, emotions, speech and cognition. We wrote the book with the intent that it could serve as an introductory neuroscience text.

Can you tell me what you learned about Haitian zombies?

I learned that belief can be a very powerful thing. Well, belief combined with powerful neurotoxins and hallucinogens, anyway.

We go into detail in our book about the cultural roots of the Haitian zombie. The word “zombie” comes from an African root word nzambi, meaning “spirit of a dead person.” Within vodou, a priest (bokor) can sometimes be asked to take possession of the soul of a particularly troubled or threatening individual. The bokor induces “death” and separates the “little good angel” spirit (ti bon ange) from the body. Once “resurrected,” the physical body of the person is then forced to work at the will of the bokor.

An anthropological investigation by ethnobotanist Wade Davis postulated that the process of making a Haitian zombie is neuropharmacological, wherein bokors use a chemical found in many animals (especially puffer fish), called tetrodotoxin (TTX), to paralyze their targets and induce a near deathlike state. A sublethal dose of TTX allows the person to “die” and be “resurrected.” During the recovery, the victim is forced to consume datura, a plant that contains chemicals such as scopolamine and hyoscyamine, powerful hallucinogens that leave the individual delirious and compliant. Datura alters the victim's state of mind, making the person easily coercible. The whole idea is fascinating. It sounds so far-fetched and unbelievable, but from a neuroscientific and psychological perspective, it's not impossible.