According to a recent study, there are at least two neural correlates for decision-making in the brain.

If you’re the scarecrow in the Wizard of Oz who yearns for a brain, you have neither of these correlates. However, if you are someone who has frontal lobe damage to the orbitofrontal cortex (OFC), you have one functional neural correlate: for action value comparisons. You can make optimal decisions about how to get a brain (…although you obviously would already have one). Alternatively, you could have suffered damage to the dorsal anterior cingulate cortex (dACC) - in which case you would be able to make stimulus value comparisons and choose which objects are optimal, such as the wittiest or the most creative brain, but not how to get the chosen object.

These findings on stimulus and action value comparisons came from the study conducted by Camille et al. at McGill University. The authors tested human subjects with frontal lobe damage to either the OFC or dACC compared to controls. The behavioral tests were computerized value-driven learning tasks that were given on two different occasions. By comparing the overlap of lesions from the brain scans of patients, they suggested that damage in certain areas either altered stimulus or action value comparisons, both of which have been known to be important in the decision-making process.

Dr. Lesley Fellows, a neurologist and research scientist at The Neuro – or the Montréal Neurological Institute and Hospital, was the principal investigator. She says, “The surprising and novel finding is that in fact these two mechanisms of choice are independent of one another. There are distinct processes in the brain by which value information guides decisions, depending on whether the choice is between objects or between actions… This finding gives me more insight into what is happening in the brain of my patients, and may lead to new treatments and new ways to care for them and manage their symptoms.”

Certainly understanding more about the decision-making process in terms of the neural correlates is important in creating and deciding on treatments for patients, as well as providing more information, coping strategies, therapy, and better care to those who suffer brain damage affecting their decision-making abilities. Not only that, but this understanding also provides a clearer perspective on frontal lobe dysfunction and other disorders that may include symptoms like indecision or risky behavior.

Decision-Making: What You Want Vs. How You Get It – Science Daily

Double Dissociation of Stimulus-Value and Action-Value Learning in Humans With Orbitofrontal or Anterior Cingulate Cortex Damage – Nathalie Camille et al.

Zombies are terrifying creatures. The most panic-inducing aspect of their completely factual existence among us is that they have a taste for human blood and they will do anything  to get to it. Recently, the Zombie Research Society (ZRS) has been attempting to scan (with some difficulty due to the fact that zombies aren’t huge fans of staying still in MRIs) and create a map of the zombie brain. A leading researcher in ZRS, Dr. Bradley Voytek, lectured about these terrors at Nerd Night SF. In his presentation he gives a medical term to describe the zombie condition: “consciousness deficit hypoactivity disorder (CDHD)- the loss of rational voluntary and conscious behavior replaced by delusional/impulsive aggression, stimulus-driven attention, and the inability to coordinate motor or linguistic behaviors.” So with those messy scans and some preliminary facts we know about the living dead, researchers such as Dr. Voytek have been able to come up with multiple images of what a real zombie brain must look like.

These facts are taken from real-life documentaries of zombie pandemics, such as Night of the Living Dead, Shaun of the Dead, and 28 Days Later. So let’s review the characteristics of zombies the ZRS has established by examining these accounts.

1. According to Major West in 28 Days Later, zombies “are futureless” and therefore no complicated cognitive behaviors would occur. That means no emotion, no love, and therefore no frontal lobe, which is probably why zombies are willing and able to devour humans without remorse.
2. Memory deficiencies occur in zombies, signifying a loss of the hippocampus. We often see short-term and even long-term loss (explaining why they will attack family and old friends). Yet researchers hypothesize there may be some long-term memory intact by examining the story of Shaun of the Dead, primarily the final scene where we see Shaun and his newly turned zombie pal playing video games like old times.
3. Illustrated by their stiff gait, zombies clearly have motor deficits (cerebellar ataxia). This means that the cerebellum has atrophied and they have significantly less area to their cerebellum than the normal human.
4. Zombies also exhibit extreme aggression and a lack of impulse control. These two symptoms can be explained by a lesion to the orbital frontal cortex, which regulates the amygdala, which then connects to the periaqueductal gray, the hypothalamus, and the thalamus. These parts of the brain control rage, fear, agression etc. A lesion on the orbital frontal cortex will cease all regulation of the amygdala and therefore we will observe a drastic increase in aggression and impulse control.
5. And finally we see a language deficit. Very rarely are zombies able to mutter more than a moan of “BRAINNNNSSSS!!!” (which is still relatively complex for their neuroanatomy). Due to this behavior we are able to discern that zombies lack Wernicke’s area (to comprehend speech) and Broca’s area (to relay thoughts through speech).

I’m guessing that you’re thinking Alright this is all fine and dandy, but when I’m attacked by a zombie how do I escape alive? Well you’re probably going to want to run faster and climb higher than the person next to you. Considering their memory deficit, you can hide for long enough and they’ll just forget about you and move on to the next prospective dinner. And remember: trying to talk or reason with a zombie is completely useless.