In decades of films, the dead have risen from the grave to stalk the living. Classic zombies go slow (a literal plodding approach of death), while modern zombies are often swifter, sometimes speedy. Though science-fiction fans will endlessly debate which is better, a new neuroscience study on the closest thing we have to zombies in real life—those who rise from the dead of sleep—tend to be the snappy kind.
In a small study published Monday in Current Biology, researchers found that sleepwalkers tended to have better locomotor control and awareness than those who don’t wander while out cold. Specifically, researchers gave study participants (when they were awake) a movement test and a mental task to do at the same time. Even though the mental task was known to interfere with motor control, the sleepwalkers could still complete the movement test with the same accuracy and at their normal, brisk pace. But the extra brain work tripped up the non-sleepwalkers: they lurched through the movement task, even though they could perform it quickly when not mentally distracted.
The finding has two main takeaways, the authors argue. First, it hints that the brains of sleepwalkers may be better wired to automate locomotor control and awareness, freeing the body to move about without full consciousness. Secondly, it suggests that there may be waking behavioral tests that potential sleepwalkers could take to help determine if they have the sleep condition.