Could Zombies Survive Freezing Pt.2: The Science

No one knows the legitimate science of The Living Dead better than Harvard Professor and ZZN Zombologist Dr. Steven Schlozman! When a reader asked us if Zombies could freeze, his name was on the short list of experts we turned to!

Dr. Schlozman has penned a fantastic book called “Zombie Autopsies” that has caught the eye of the Zed Godfather himself George A. Romero. Even with a movie in the works and all of his Doctor Duties, Dr. Schlozman always makes time to answer a good Zombie Question.

Just a heads up, Dr. S defines a Zombie as an Infected person not a return from the dead type… you’ll see:

OK. So we all know that Max Brooks’ books tell us that we can be less concerned with zombies in cold weather. Indeed, in his book, there is almost a direct correlation with traveling North and increasing your safety form attack. However, his zombie also (true to the trope) an walk under water.

The zombies I tried to describe, while not any more real than Max’s or anyone else’s, have as their guiding principles the fundamentals of normal physiology. That makes the question of whether zombies can be frozen or not deceptively complex.

Let’s establish the rules first, then.
-Zombie have beating heart and breathing lungs. I know that’s a bit atraditional, but from physiologic standpoint you can’t have anything organic walk without some kind of oxidative metabolism (the process of using oxygen and glucose to create energy), and that oxygen has to be carried around the body somehow. For the sake of argument, let’s just say that it is blood that carries – i.e. movies – to carry the oxygen.

-Let’s leave out for the time being whether or not we define them as dead. They’re not anyone you’d want to take to prom – leave it at that. In my book, they are ecumenically and philosophically dead to allow me the conceit of saying that they are still the “the walking dead” despite their active metabolism.

-They are febrile. After all, we are invoking more often an infectious etiology in creating the zombies, and infections trigger fevers among other immune responses. They’re also likely to have other reasons for fever – a dysfunctional hypothalamus (the region of the brain that is concerned, among other things, with a sense that you’ve eaten enough and with maintaining core body temperature.

-Zombie muscles move like our muscles- that is, actin and myosin, the proteins involved in muscle movement, slide past one another to create motion.

So, what does the research tell us? Well, for humans, muscle contractions decrease with cold. This is a function of vasoconstriction that occurs at the peripherery in the cold to preserve core warmth, and delayed neuromuscular chemical signals. We know that iosmetric work (short term bursts of work) are affected less than dymamic exercise (long term exertions), and we know that in general the whole organism gets slower. We also know that organisms who decrease their core body temperatures don’t think as well, probably because of decreased blood flow and because of diminished neurotransmission and electrical activity in the brain.

So, zombies aren’t all that different. Their core body temperature will start hotter (they’re febrile) but the cold’ll catch up to them. Actin and myosin will be less functional, and whatever measly brain function they enjoy with which to find food will be hindered. Remember, though, that the very act of eating creates energy, and energy allows heat. They’ll move slower, but they can still move. If they can catch you and take a bite, then they’re gonna look better by virtue of the increased heat, and with each bite they’ll get stronger exactly as whatever their biting weakens. Know your enemy. Dress warmly among cold zombies, and don’t walk while texting. They’re still dangerous.

Steven C. Schlozman, M.D.
Assistant Professor of Psychiatry, Harvard Medical School
Co-Director, Medical Student Education in Psychiatry, Harvard Medical School
Associate Training Director, Child and Adolescent Psychiatry, MGH/McLean
Staff Psychiatrist, Massachusetts General Hospital
Zombie Zone News Zombologist
Autor, “The Zombie Autopsies”

So now that we have the Zombie Science down, stay tuned for Roger Ma’s take in Part 3!