Let’s begin with this recent experiment by neuroscientists at Rutgers, which demonstrated that general intelligence (at least in rodents) is mediated by improvements in selective attention. Here’s the abstract:
In both humans and mice, the efficacy of working memory capacity and its related process, selective attention, are each strongly predictive of individuals’ aggregate performance in cognitive test batteries. Because working memory is taxed during most cognitive tasks, the efficacy of working memory may have a causal influence on individuals’ performance on tests of “intelligence”. Despite the attention this has received, supporting evidence has been largely correlational in nature. Here, genetically heterogeneous mice were assessed on a battery of five learning tasks. Animals’ aggregate performance across the tasks was used to estimate their general cognitive abilities, a trait that is in some respects analogous to intelligence. Working memory training promoted an increase in animals’ selective attention and their aggregate performance on these tasks. This enhancement of general cognitive performance by working memory training was attenuated if its selective attention demands were reduced. These results provide evidence that the efficacy of working memory capacity and selective attention may be causally related to an animal’s general cognitive performance and provide a framework for behavioral strategies to promote those abilities. Furthermore, the pattern of behavior reported here reflects a conservation of the processes that regulate general cognitive performance in humans.
Obviously, every discussion of general intelligence in the context of mouse performance is bracketed by lots of question marks. Nevertheless, I think this research can help clarify what, exactly, intelligence is, and why it’s so important. I think most people assume that intelligence is largely a matter of learning and memory, so that smarter people end up with more facts in their head. (We’ll call this Trivial Pursuit model of intelligence.) This helps explain why people searched for centuries for a correlation between brain mass and raw intelligence, as if Einstein was nothing but a massive hard drive.
This rodent experiment, however, argues that intelligence is really about the ability to control the spotlight of attention. After all, having access to facts doesn’t matter if we can’t focus on the facts, or figure out which facts are actually important. (Herbert Simon said it best: “A wealth of information creates a poverty of attention.” To push Simon’s metaphor a bit farther: Intelligence, then, is like a savings account that keep us from going broke when faced with too much information.) This is why training mice on selective attention tasks makes them smarter – it allows them to make better use of all the relevant information that’s already out there.
This reminds me of the ideas I wrote about in the New Yorker last year, while discussing the work of Walter Mischel and the marshmallow task. Mischel pioneered a delayed gratification protocol in which four-year olds were given a choice between eating one marshmallow right away or waiting 15 minutes and getting two marshmallows. It later turned out that the ability to delay gratification as a little kid was a powerfully predictive test, and that kids who could delay for longer scored higher on the SAT, had fewer disciplinary problems and responded better to stressful situations.
At the time, psychologists assumed that children’s ability to wait depended on how badly they wanted the marshmallow. But it soon became obvious that every child craved the extra treat. What, then, determined self-control? Mischel’s conclusion, based on hundreds of hours of observation, was that the crucial skill was the “strategic allocation of attention.” Instead of getting obsessed with the marshmallow–the “hot stimulus”–the patient children distracted themselves by covering their eyes, pretending to play hide-and-seek underneath the desk, or singing songs from “Sesame Street.” Their desire wasn’t defeated–it was merely forgotten. “If you’re thinking about the marshmallow and how delicious it is, then you’re going to eat it,” Mischel says. “The key is to avoid thinking about it in the first place.”
Mischel’s large data set from various studies allowed him to see that children with a more accurate understanding of the workings of self-control were better able to delay gratification. “What’s interesting about four-year-olds is that they’re just figuring out the rules of thinking,” Mischel says. “The kids who couldn’t delay would often have the rules backwards. They would think that the best way to resist the marshmallow is to stare right at it, to keep a close eye on the goal. But that’s a terrible idea. If you do that, you’re going to ring the bell before I leave the room.”
According to Mischel, this view of will power also helps explain why the marshmallow task is such a powerfully predictive test. “If you can deal with hot emotions, then you can study for the S.A.T. instead of watching television,” Mischel says. “And you can save more money for retirement. It’s not just about marshmallows.”
In other words, delayed gratification isn’t really about gritting our teeth or exerting willpower: it’s about controlling the spotlight of attention. Likewise, intelligence isn’t just about remembering abstract facts – it’s about controlling what thoughts we’re thinking about in the first place. (To put it another way, being smart is not just about having a larger working memory – it’s about having more precise control over what’s in working memory.) The brain is a bounded machine and the world is a confusing place, full of errata and distractions – intelligence is the ability to parse reality so that it makes just a little bit more sense. (As William James famously wrote, “Everyone knows what attention is…It implies withdrawal from some things in order to deal effectively with others.”) Our mind has strict cognitive limitations – selective attention helps us compensate.
So how can we bolster our selective attention abilities? This is pure speculation, but I see research like this as an important defense of difficult novels. When we read a complex narrative – say, Proust or Woolf or DFW – we’re forced to constantly exert our attentional muscles just to follow along. On a deeper level, however, we’re also being asked to switch between different kinds of informational streams. We need to pay attention to the sentence, and to the subtleties of language and character and plot, but we need to also remain aware of the larger themes unfolding in the work. Is this Marcel the narrator? Or Marcel the author? What is Proust telling us about memory and Paris and jealousy? Unpacking the text, in other words, is an extreme form of cognitive exercise, as we must alternate for hundreds of pages between local comprehension (the sentence and the mechanics of plot) and global understanding (the larger meaning of the novel). That’s not easy, and it’s often not particularly fun. (Why read Proust in an age of YouTube and the Twilight Saga?) But the difficult novel just might make you a touch smarter. It might even make it a little easier to not eat the marshmallow.