On Monday, I put up a post on whether we would ever be able to upload our brains into a computer, merging ourselves into the great digital Singularity that would provide us with eternal life—and virtually infinite sensory powers and intelligence. The take home: This is akin to a cargo cult-like religion. Don’t hold your breath (or freeze your brain) in anticipation.

On Tuesday, I received notice of a new study with a title that addresses, in a sense, a similar question from a more real-world perspective: “Why Aren’t We Smarter Already: Evolutionary Trade-Offs and Cognitive Enhancements.”

The two psychologist authors—Thomas Hills of the University of Warwick and Ralph Hertwig of the University of Basel—start their article in Current Directions in Psychological Science—by invoking the current fascination with pharmaceutical enhancement of our cognitive skill set, whether of memory, our ability to focus, or the speed with which we process information.

They cite one of the best exemplars of this fascination: a 2008 essay entitled “Toward Responsible Use of Cognitive-Enhancing Drugs”— that appeared in our sister publication Nature, and which was co-signed by its editor Philip Campbell. (Scientific American and Nature are part of Nature Publishing Group.) The authors of the Nature paper concluded that cognitive enhancers “should be viewed in the same general category as education, good health habits, and information technology.”

In their critique, Hill and Hertwig question whether such a comparison is apt. A calculus course is not subject to evolutionary pressures, as are cognitive faculties like memory or attention. The class feedback form at the end of the semester is not the same as natural selection working on the gene pool.

So, if evolution is the driver, why then haven’t we evolved to possess the traits that Provigil or Ritalin endow us with? Why can’t we go without sleep for 48 hours to master Mandarin characters for the HSK proficiency test or to memorize the Friedel-Krafts alkylation reaction for the Orgo II final?

The answer, of course, has to do with the evolutionary tradeoffs. Too much memory, attention or willpower, instead of making us into uber-geeks, might drive us the way of the wooly mammoth. Our gift as a species—what brought us on an evolutionary track from the Flintstones to Steve Jobs and the iPhone 4S (Hmmm. Is Jobs the best example?)—relates to our capacity to allocate just enough cognitive resources to the task at hand to get the job done.

Those who can’t engage in this mental balancing act run into problems. People with too much working memory—the mental scratchpad that lets you recall a telephone number while dialing—may have difficulty hearing their own name in the chatter of a cocktail party or even remembering a phone number if they are hustled from one room to the next too quickly. The laser-like attention that allows them to store a multitude of facts in mental RAM diverts them from registering the world around them and they seem to become disoriented when brought back from their introspecting. Back in the day, they might have ended up as dinner for a saber-tooth tiger.

Most of today’s cognitive enhancers improve our ability to focus—but most benefits accrue to those with attention deficits. They allow the child with ADHD to learn the multiplication tables, but for those with average attention spans or better, these drugs can sometimes usher in comic mishaps.

Instead of cramming for the HSK, as you might have intended, you are liable to get sidetracked into the most mundane of trivialities: you might get up from your textbooks for a drink of water and spend the next two days replacing the leaky plumbing in your kitchen sink. The focus of attention “sticks” to whatever is in front of your face and a friend with a verbal crowbar has to pry you away.

The Hills and Hertwig paper suggests that any putative cognitive enhancer must be carefully optimized with methods from the psychological sciences to, say, balance attention against “perseveration,” staying too long on a given task. The graphs would calculate when any gains start to bump up against diminishing returns. For most of us in the center or the right end of the Bell Curve, the upside to enhancement probably flattens out pretty quickly. The other tradeoffs the authors consider are primarily physiological. The reason, for instance, we don't have bigger brains, with a corresponding increase in cognitive capacity, is that women's pelvises would have had to get larger. A bigger pelvis could make running or climbing trees tough. Again, from the standpoint of Paleolithic living: good for the saber tooth, bad for Homo S.

After reading the paper, I asked Hills via e-mail about the Flynn Effect, the observation that IQ has improved steadily in recent decades in the general population. He replied that the Flynn Effect only proves his point: “The gains in intelligence are dominantly in the lower half of the distribution. The smarter folks do not appear to be getting smarter.
” The message for many of us is that we are probably nearing our sweet spot. Things are about as good as they get.

Source: Wikimedia Commons