A recent article in the New York Times discusses the hot new trend in English departments--the study of why we read fiction in the first place.
This is still far from being a cohesive area of study. Some are pursuing the idea that fiction provides models for altruistic cooperation, or other patterns of human interaction. This, of course, is an old idea, which harks back to Colin Wilson's contention that a novel is a "philosophical experiment." (Wilson meant this in the most literal, scientific sense: he argued that fiction acted as a lab experiment where we could take certain kinds of characters, situations, and approaches to life, and set them in motion to see the results.)
Others think that fiction is innately attractive because constructing theories as to the inner workings of the minds of others--their "intentionalities," in the jargon of the studies--has an intrinsic evolutionary value to creatures as social as humans. Included are level problems of tracking who knows what--does Tim know that Jill knows that Bob knows about X? Scholars who puzzle over such things have decided that Virginia Woolf is often difficult because she is demanding that the reader track too many different minds and intentions.
A researcher with the marvelous (if implausible--but this is nonfiction, here) name of Lisa Zunshine claims that our ability to track states of knowledge drops off quickly when more than three minds are included. The article gives the example of "“Peter said that Paul believed that Mary liked chocolate” as a case that we can follow with some degree of ease; add another link in that chain, and our comprehension of what is happening drops off quickly.
Furthermore, Zunshine and others claim that following the interaction of three minds has an innate draw for humans. That's certainly true; while the protagonist/antagonist duo are the pillars of classical storylines, it's hard to get a story rolling without throwing in a third element to thicken the plot; and what's a love story without a triangle?
I've also read elsewhere that most primitive arithmetics use a counting system which itemizes as "One...Two...Three...Many." Some psychologists have argued that the brain has an innate understanding of one, two, and three, but that when we see larger numbers, we "re-chunk" them; that is, when we see three people walking down the street, we know instantly we are seeing three people, but when we see four people, our initial impression is that we see "many," which we promptly chunk into, say, two pairs of people to arrive at four. And why not? After all, we live in three dimensions.
The article also reports that some of the fiction researchers are hoping to deploy the current sexy science device, the MRI brain scan, to study changes in the brain while we consume fiction.
I have to confess a high degree of skepticism about MRI brain imaging. Last year Science News published a short review of the statistical and interpretive problems with such studies, highlighted by by a study where emotional reactions were traced in the brain of a salmon when it was shown humans engaged in various activities. It would be amazing if a fish were reacting to such stimuli in a predictable way, but what was truly fascinating about this particular experiment is that the fish was dead.
Either there are some basic flaws in how this data is analyzed (which the Science News article argues most convincingly), or fish consciousness survives death, and hangs around the region of the fish's body before passing to the Great Beyond.
In any case, we will soon have more pictures (possibly of questionable value) of Your Brain On Fiction. And, with a bit of luck, perhaps we'll also know how many levels of intentionality a fish can track.