How To Survive A Zombie Apocalypse
Find a mountain range, keep quiet, mimic the way the undead walk and NEVER fight
From a remote farmhouse to a shopping mall and even a bar, films are full of suggestions of where to hide out in the event of a zombie apocalypse.
But researchers have developed an apocalyptic simulator that suggests the best thing to do is literally run for the hills - if you live in the US at least.
Other advice from scientists-turned zombie experts, includes keeping silent and even mimicking zombie behaviour should you run into one of the fictional reanimated corpses with a taste for human flesh.
Use the simulator below to start a zombie apocalyse. Mobile users who cannot see the module can visit this website to play.
Researchers from Cornell have developed an apocalyptic simulator (shown above for web browsers) that suggests the best thing to do is literally run for the hills – if you live in the US at least.
Physicists Alexander Alemi, Matthew Bierbaum, Christopher Myers and James Sethna created a zombie simulator (screenshot shown of an uprising of the undead beginning in New York City) based on techniques used in in epidemiology – the study of how disease spreads and can be controlled – to work out how the apocalypse might play out in the US.
Physicists Alexander Alemi, Matthew Bierbaum, Christopher Myers and James Sethna of Cornell University, created a zombie simulator based on techniques used in in epidemiology – the study of how disease spreads – to work out how the apocalypse might play out in the US.
Their simulator allows users to choose the origin of where the zombies rise from the dead in the US, as well as change how quickly they can walk and bite, to infect humans.
Using the tool, they found cities would fall quickly, but it would take weeks for zombies to penetrate into less densely populated areas, and months to reach mountains in the northern states, meaning their advice is to head for the Rockies.
They worked on the basis there are four states a person can be in: human, infected, zombie, or slain zombie and these are dependent on possible interactions, including a zombie biting a human and a human killing a zombie, for example.
The simulator accommodates fluctuations in the ferocity of zombie attacks using a Gillespie algorithm - a probability tool from computational chemistry that's useful in situations where outcomes may depend on random events, the Institute of Physics' magazine, Physics World reported.
This means it can account for every single human–zombie interaction, making it possible, for example, for 'patient zero' or the first zombie to be killed and the whole plague nipped in the bud before it really begins.
The simulator accommodates fluctuations in the ferocity of zombie attacks using a Gillespie algorithm – a probability tool from computational chemistry that's useful in situations where outcomes may depend on random events.
The simulator treats each person and zombie as if they are a node on a lattice, allowing them to only interact with the next node, so the 'spread' of the undead is as realistic as it can be.
The experts also used first-order differential equations to take into the account the movement of zombies and humans in their tool.
'Given the dynamics of the disease, once the zombies invade more sparsely populated areas, the whole outbreak slows down - there are fewer humans to bite, so you start creating zombies at a slower rate,' Alemi told Phys.org.
The simulator revealed lots of interesting patterns, including that an outbreak takes on the same shape on both large and small scales, with the most populated areas being affected first.
While the experts advocate heading to remote, rural areas, their study pessimistically notes 'that for 'realistic' parameters, we are largely doomed.'
The researchers are not the first to use maths to model the spread of zombies. Robert Smith, a mathematician who studies infectious diseases at the University of Ottawa, in Canada, started the trend.
Neuroscientists analysed the behaviour of the walking dead to reveal the inner workings of their mind and coined a diagnosis of 'zombisim'. This diagram shows parts of the brain that are responsible for certain zombie behaviours, such as impulsive aggression and difficulty processing emotions.
Hungry: Zombie fanatics Timothy Verstynen, of Carnegie Mellon University and Bradley Voytek, of University of California, San Diego, summarised characteristic zombie behaviour seen in films, including Shaun of the Dead. A screenshot showing hungry, slow-moving zombies is pictured.
In a 2009 paper, he described the first modern zombie model, using popular films such as the 1968 classic Night of the Living Dead to establish the biological characteristics of the slow-moving, cannibalistic creatures.
Since then interest in zombie modelling has exploded.
'Now we've got people reading math papers with equations in them - people who would never normally read such a thing and would run a million miles to get away. You add zombies, and suddenly it's interesting,' he said.
Two neuroscientists have also used zombies to reveal the inner workings of our brains as well as explaining the behaviour of the walking dead, to come up with a comprehensive diagnosis of 'zombiism'.
Timothy Verstynen, an assistant professor in the department of psychology at Carnegie Mellon University in in Pittsburgh, Pennsylvania, and Bradley Voytek, assistant professor of cognitive science and neuroscience at the University of California, San Diego, summarised characteristic zombie behaviour seen in films, which can be explained by looking at the structure of the brain.
There are two subtypes of the syndrome – CDHD-1, which affects 'slow' zombies with uncoordinated movements and CDHD-2, which is typical of 'fast' zombies that have no problem chasing humans in films, such as 28 Days Later (a screenshot is shown) and World War Z. They have dubbed the condition 'Conscious Deficit Hypoactivity Disorder', or CDHD, which they describe as an acquired syndrome in which infected people lack control over their actions.
In films, the undead display symptoms such as lethargic movement, loss of pleasure, language dysfunction, amnesia and the inability to suppress hunger and aggression.
'Zombies often have difficulty recognising familiar people and suffer chronic insomnia that results in a delirious state,' they write.
Undead individuals would also exhibit antisocial behaviour, such as biting and eating people, but they would be friendly to each other and swarm with other infected individuals, according to the scientists' book, 'Do zombies dream of undead sheep?'.
The neuroscientists have come up with two subtypes of the syndrome – CDHD-1, which affects 'slow' zombies with uncoordinated movements and CDHD-2, which is typical of 'fast' zombies that have no problem chasing humans in films.
This may be because at the moment of death, our circulatory systems stop, starving the brain of oxygen and glucose.
In zombie films, they resume at the point of infection - in a limited form - and the brain gets its nutrients by zombies feasting on human flesh.
The longer the brain is starved of oxygen, the more extensive the damage to zombies, the neuroscientists say.
CDHD-1 zombies can be seen in the TV series, The Walking Dead, while the zombies in Waord War Z are faster and typical of CDHD-2.
The brains of both types of zombies would change in different regions, from a combination of decreased activity and altered activity in multiple brain networks.
Lesions to the temporal lobe would partly cause zombies to act like they do in films.
Terror: The cerebellum, a region of the brain that plays an important role in motor control, is likely to degenerate in CDH1-zombies, explaining their severe coordination difficulties in films, but CDHD-2 zombies (illustrated in the film, 28 Days Later) have less damage in this area of the brain, making them more agile.
Shortsighted: Zombies are known for their poor eyesight and visual impairment would come from damage to the parietal lobe. It perhaps explains why CDHD-1 zombies, such as those seen in the TV show, The Walking Dead (screenshot pictured), can only look straight ahead and see one object at a time in films.
Specifically, damage to the fusiform gyrus would impair the undead's ability to recognise faces, while damage to the superior temporal gyrus would hamper their ability to process emotional facial expressions, resulting in apathy to the feelings of others.
Professors Verstynen and Voytek say lesions in the temporal parietal junction - an area of the brain where the temporal and parietal lobes meet - would result in severe difficulties in understanding language and in speaking; making communication difficult and causing slurring, as seen in films.
Meanwhile, damage to the medial temporal lobe – especially the hippocampus, which is responsible for memory and navigation - would mean that zombies couldn't form new memories and would find it hard to find their way around towns, giving humans a change of surviving an apocalypse.
Zombies are known for their poor eyesight and visual impairment would come from damage to the parietal lobe. It perhaps explains why CDHD-1 zombies can only look straight ahead and see one object at a time in films. Problems with spatial attention as a result of this injury, would also make general motor skills difficult.
CDHD-2 zombies, however, would not suffer as much damage to this brain region, according to the scientists.
But both types of zombie would have sustained 'extensive damage' to the frontal lobe, which is responsible for immediate tasks, planning, and motivation.
Hungry for emotion: Damage to the cingulate cortex would mean that individuals may feel conflicted about emotional attachment to people and eating them, but they would not be able to suppress the desire to eat. A zombie from the Resident Evil video game, which features zombies classified as type CDHD-2 type is pictured.
The inability to suppress inappropriate responses, such as the desire to eat people would be due to damage in the orbitofrontal cortex, while damage to the dorsolateral prefrontal cortex would make decision making difficult.
Lesions to the interior frontal cortex, especially Broca's area,which is linked to speech production, would result in communication difficulties.
Damage to the cingulate cortex would mean that individuals may feel conflicted about emotional attachment to people and eating them, but they would not be able to suppress the desire to eat.
The cerebellum, a region of the brain that plays an important role in motor control, would likely degenerate in CDHD-1 zombies, explaining their severe coordination difficulties in films.
'Individuals exhibit a wide stance and lumbering gait as well as difficulties reaching and grasping,' professors Verstynen and Voytek write.
Damage to this area of the brain would also lead to slurred speech, but CDHD-2 zombies would be spared extensive cerebellar damage, making them more eloquent.
Zombies' insomnia could be explained by lesions in the hypothalamus, which links the nervous system to the endocrine system.
In the mid-brain, lesions to the amygdalae - two almond-shaped groups of nuclei located deep within the temporal lobes of the brain - may explain enhanced fight or flight behaviours in zombies on the silver screen, expressed as impulsive aggression.
However, primary sensory areas of the brain that allow humans to process sights, sound, smell, touch and taste signals would remain intact, meaning that zombies could use all sensory information, but wouldn't respond emotionally to it.
Some areas of the brain allowing basic movement, such as the thalamus - which is used to process neural signals - and the brainstem, would function as usual upon infection, the neuroscientists explain.
'In conclusion, the series of brain changes seen in CDHD, reflect a loss in so-called 'higher order' cognition areas and the neocortex the CDHD-1 subtype also reflects a degeneration of the cerebellum,' they say.
Eloquent: CDHD-2 zombies would be spared extensive cerebellar damage in the event of a zombie apocalypse, making them more eloquent and able to understand speech. The CDHD-2 type can be seen in the film, World War Z (a screenshot is pictured) which stars Brad Pitt as the hero.
In humans, tapeworms (shown in an MRI scan) can make its way into the brain to change our behaviour, but a microbe called Toxo plasma gondii (T.gondii) goes a step further. Found in cat faeces, it can infect humans and stop them fearing risky behaviour, with tragic results.