Obviously no one expects to find a zombie reading the latest New York Times bestseller. Even the most voracious reader will lose their appetite for literature once they’ve joined the ranks of the living dead. But we still don’t know exactly how far gone they really are; can zombies actually read or comprehend anything at all, will they still understand symbols or street signs?
If something as simple as an arrow can trigger a memory, prompt a response, and lead the undead to your location; perhaps its time to learn more about how our brains really work. So lets take a closer look at the left fusiform gyrus, aphasia, and visual processing disorder!
Aphasia is the inability to comprehend or formulate language because of damage to the brain including head trauma, tumors, and infection. In fact, the dramatic link between reading comprehension and the left mid-fusiform gyrus of the brain was made abundantly clear during clinical research from Johns Hopkins University almost ten years ago.
We report on an investigation of the cognitive functions of an individual with a resection [surgical removal] of the left fusiform gyrus … The results clearly reveal deficits affecting lexical processes in both reading and spelling. Specifically, we find disruption of normal, rapid access to meaning from print in reading and of accurate retrieval of the spellings of words from their meaning in writing … that are specialized and necessary for normal orthographic processing.
Basically, they took out part of someone’s brain and he was no longer able to read or write very well. While that isn’t especially surprising, it does provide evidence that zombies can slowly lose their ability to read, write, and even comprehend a written language due to the same deadly infections responsible for aphasia itself. But there’s just one little problem.
Their findings actually stood in stark contrast to the patient’s verbal and visual abilities. He was still able to speak coherently, and even recognize line drawings, symbols, and faces. So perhaps aphasia can only account for a small part of the behavior we attribute to zombies.
After all, zombie decay theory is in its infancy. The transformation that our brains and bodies undergo from living to undead is a sliding scale; incremental and cumulative rather than a straight line from point A to point B. And there are many more factors to be examined.
For example; consider visual processing issues. These are not the same as aphasia, dyslexia, or simple vision problems that can be fixed by glasses. In this case the brain actually has trouble making sense of the information taken in through our eyes. Symptoms include poor spatial awareness, trouble telling the difference between the size, shape, and color of objects, and most importantly, confusion about written symbols. That sounds more like a zombie!
Unfortunately, researchers simply don’t know what cause these visual processing disorders. Some studies suggest that traumatic brain injury could lead to VPD, but there isn’t enough research to support that theory. Regardless, this condition could eventually explain why the undead brain loses its ability to comprehend the street signs, signals, and cues all around them during the inevitable zombie apocalypse. It remains a mystery waiting to be solved.
Of course, if you’d like to help solve that mystery we suggest starting with the articles cited above, including “The orthography-specific functions of the left fusiform gyrus: Evidence of modality and category specificity” available online at ScienceDirect, or “Mild traumatic brain injury induces prolonged visual processing deficits in children” published via the US National Library of Medicine National Institutes of Health. After all, what you don’t know can eat you!