Be sure to visit The Cognitive Axon tomorrow for symptom 8!
Symptom 7: Stimulus-locked attention
If zombies are anything, they're at least highly distractible. Don't want them to see that you're looting an old corner store for supplies? Throw up a few fireworks. The walking dead will be occupied as long as the show lasts.
Of course, this type of attention can be deadly if the critters set their sights on you...
This type of stimulus-bound attention reflects another rare clinical disorder called simultanagnosia. Simultanagnosia, particularly the "dorsal form", is the inability to attend to more than one thing at time and is often seen in patients suffering from Balint's Syndrome.
The only thing these patients perceive is whatever has grabbed their attention. This originates when both the left and right parietal cortex, the back and top part of your neocortex, are lesioned. If one is intact, spatial attention is still somewhat impaired, but the impenetrable stimulus-locking does not occur.
Damage to this parietal network may also underlie some of the issues we previously described with the mirror neuron network, language regions, and pain sensory regions.
So, along with a good chunk of the frontal lobe, it's safe to assume that the dorsal parietal lobe is lesioned in the zombie brain as well. This could happen if the neurons themselves are destroyed, or if the axons connecting them (called "callosal fibers" because they pass through the corpus callosum) are damaged.
Only careful, clinical trials can tell us the true root cause of this damage in the zombie brain. Nevertheless, by arming ourselves with the knowledge of the zombie’s simultanagnosia, we can devise further survival strategies. More on this later.