Two scientists try to answer the question: How would the inside of a zombie's head look?
October 14, 2013 4:00 AM
Timothy Verstynen of Carnegie Mellon University's Cognitive Axon Lab discusses zombie brains to interest people in neuroscience.
Timothy Verstynen and his collaborator, Bradley Voytek, teach brain-behavior relationships using models of "zombie brains." Each model is essentially an image from a mock MRI exam, as if the researchers had strapped a zombie down and slid it into an MRI scanner.
By Kathryn Sterling Pittsburgh Post-Gazette
The sign on the door to his office reads, "Warning! Zombie Contagion / Do Not Enter!"
Carnegie Mellon University's Timothy Verstynen, 35, is quick to call himself a nerd -- in the confident way of someone who knows that nerd is the new cool. An assistant professor in psychology at CMU and the Center for the Neural Basis of Cognition (a joint venture of CMU and the University of Pittsburgh), he is engaged in science outreach that combines two of his favorite things -- horror movies and brains.
Mr. Verstynen directs the Cognitive Axon Lab at CMU. "My actual work looks at how the architecture of the brain gives rise to our actions and our decisions," he says. "So I look at how the brain is wired together using a type of MRI, and then I look at how the brain functions when you're doing different tasks." On the side, Mr. Verstynen and his collaborator, Bradley Voytek, teach brain-behavior relationships using models of "zombie brains." Each model is essentially an image from a mock MRI exam, as if the researchers had strapped a zombie down and slid it into an MRI scanner. This "research" is all in good fun; it's not serious science, but a teaching tool that capitalizes on the public's fascination with zombies.
The CMU professor and Mr. Voytek, who is based in California, have given talks on the neuroanatomy of zombies throughout the country and are focusing now on writing a book for high school and early college students. "We're basically trying to fool [them] into reading and learning about the brain by talking about it in terms of zombies," Mr. Verstynen says.
The two researchers created three models of zombie brains to reflect the spectrum of zombies found in pop culture. There's one for a slow zombie as you'd see in a George Romero film and another for a fast zombie, as if from "28 Days Later." The third model represents the brain of an "early infected" zombie. "I call this my 'Warm Bodies' brain," Mr. Verstynen says. "You know, the zombies that are just human enough that they can come back."
An MRI of a normal human brain shows healthy tissue -- complete with gyri and sulci, or bumps and grooves -- packed inside the skull. The zombie MRIs, in contrast, exhibit empty regions where the brain has decomposed.
To create the models, the researchers first had to analyze zombie behavior to figure out what is going wrong in the creature's brains to make them behave the way they do. Studying zombie behavior is something that the University of California, Berkeley, prepared them well for: "We would watch zombie movies together in grad school and geek out about a lot of stuff," Mr. Verstynen says.
Armed with their list of zombie behaviors, they then had to link the behaviors with the appropriate regions of the brain. For example, since zombies can't speak, the researchers posit that they likely suffer from damage to areas in the language circuit of the brain. Specifically, in what is known as Wernicke's area, which is responsible for language comprehension, and Broca's area, which is involved in language production. So to make the model, the researchers took an MRI of a human brain and used a computer program to isolate specific regions -- like Wernicki's and Broca's areas -- and eroded away the tissues there.
The cerebellum, a cauliflower-shaped region at the back of the brain, does not fare well in the zombie brain, either. The cerebellum is involved in functions such as coordination, timing, motor control and language -- all areas in which zombies exhibit behavioral problems. In fact, Mr. Verstynen says that the gait of slow zombies is similar to that of people with ataxia, a degenerative disorder linked to the cerebellum. "We took out the cerebellum in the zombie brain, but if your cerebellum was atrophied to that degree, you'd be dead."
Even in the slow zombie brain, however, a significant amount of brain matter remains. "We teach not just by what areas are damaged, but by what areas are also supposedly spared," Mr. Verstynen says. Thus the visual, auditory, motor, and somatosensory cortices remain intact, since zombies can see, hear, move around, and respond to stimuli.
"Obviously zombies aren't real, so we're not necessarily needing to capture all the zombie behavior," Mr. Verstynen says. The researchers do, however, have a hypothesis that accounts for the behavior of both fast, modern zombies and more traditional, slow zombies. They jokingly call it the Time To Resurrection Hypothesis in a tongue-in-cheek nod to their field's penchant for labels.
The Time To Resurrection Hypothesis is based on hypoxic brain damage, or damage from lack of oxygen. The brain accounts for only a small percentage of the body's mass but uses about 20 percent to 25 percent of the body's oxygen and glucose. "You can think about the brain as being the U.S. of the global energy supply of the body," Mr. Verstynen explains. "So when you're starved for resources, tissue starts to die off relatively quickly in the brain." Thus, the longer it takes for a corpse to reawaken as a member of the undead, the more damaged the brain will be, and the slower the zombie.
The main goal of this "zombie schtick" is to give people "a general understanding of the brain's link to behavior, that there are nuances in the way that things are represented in the brain," Mr. Verstynen says. "That's the big take-home message, that there are lots of areas of the brain that come together to give rise to behavior." In other words, no single region determines movement, or anger and impulse control, or any other system. "The brain is much more complicated than people even give it credit for," he says.
Mr. Verstynen is passionate about his role as an educator because he'd like to see more students interested in STEM fields, and more people in general thinking scientifically.
"I'm always concerned that, as a scientist, we're kind of losing the culture war, or the culture battle," he says, explaining that nearly one-third of the population does not believe in evolution. "That's a significant number of people who just don't believe in an empirically proven form of science." And the best way to get people to think like scientists is to connect science with topics that are inherently engaging, like zombies.
Mr. Verstynen, who became a faculty member at CMU in 2012, has received mostly support within the academic community for his outreach endeavors. "Some of the older professors have expressed concern about going down this road, thinking that it would be trivializing science or a distraction from doing my own research," he says. "Actually that's been more of a minority than I expected. I've gotten a lot of support from Carnegie Mellon."
That support should ease his mind. When asked what he fears, the zombie researcher says, laughing, "I'm afraid of not getting tenure." After thinking about it some more, he says, "I am afraid that zombies will get turned into the next 'Twilight.' That's my real fear. I don't want a moody zombie that sparkles in the daylight."