At Discover, the Neuroskeptic probes a bit into research on people who for one reason or another are missing large parts of their brains.
Due to a condition called "hyrdrocephalus," some people have large areas of brain tissue essentially replaced by water. The word hydrocephalus literally means "water brain." After treatment, some of the people who suffer from this fluid buildup are found to have the missing brain tissue and the water in its place. But as the Neuroskeptic notes, some of these people seem to suffer little or no loss in cognitive function or memory. Some scientists have suggested that this means not all of our brain tissue is strictly necessary, and that the brain's ability to store information doesn't scale up or down with its size.
One British researcher even suggests that the information previously stored in the brain tissue now replaced by water is somehow still stored, either in the fluid itself at some sub-atomic level or perhaps even in a kind of metaphysical version of a cloud computer server.
The Neuroskeptic is properly skeptical of such a claim, noting that while much of the brain tissue was replaced by fluid in these cases, not all of it was, and it may be that the remaining tissue happens to be that which the brain needs to run the body and retain its thinking ability. It's also possible that the remaining tissue is somehow dense enough that it can take over the functions previously handled by a larger volume of that same tissue.
Studies on this matter remain limited enough that answers are as yet unclear. Hence the question in the Discover blog post headline, "Is Your Brain Really Necessary?" At first it might seem scanning certain persons who are quite obviously operating without brains might be a promising path of investigation. Pick a group of people who, say, take Al Sharpton or Don Imus seriously, support Donald Trump for president, think Che Guevara was a hero, watch TLC reality shows or commit some other action indicative of extremely low levels of cognitive function. Scan their brains to see if their skulls contain fluid or brain tissue. If they contain fluid, then voila! a link between the absence of brain tissue and really really dumb ideas is proven.
But a problem arises. If these scans show these skulls to be filled with the ordinary sort of gray matter we all have, then we have not yet determined whether or not a brain is necessary to modern American life. We have only determined that the use of a brain is not necessary to modern American life. And given things like Kardashians, Sean Penn and Mike Huckabee thinking enough people want to vote for him for president that he could win, that's information we already have.