[podcast]https://edwardwillett.com/wp-content/upLoads//2009/06/Cognitive-Shortcuts-to-Obesity.mp3[/podcast]
When we think about how we make decisions, we tend to imagine that we consider the facts of a situation carefully and logically, in a straightforward, step-by-step manner.
But that process is, indeed, imaginary. The truth is that our brains prefer to do as little actual thinking as possible. They like shortcuts—and sometimes those shortcuts can get us into trouble.
Take, for instance, what psychologists at the University of Pennsylvania call “Unit Bias,” which, they say, “causes people to ignore vital, obvious information in their decision-making process, points to a fundamental flaw in the modern, evolved mind, and may also play a role in the American population’s 30 years of weight gain.”
The researchers conducted several studies with college-age participants. In one, the participants were asked to estimate the weight of adult women, whose height they were told, by either looking at photographs or at the woman in person. Other students were asked to estimate the calories in one of two actual meals, both of which contained the same foods, but one of which had larger portion sizes.
The researchers found that the students estimating the women’s weight disregarded or ignored the height information they were provided and based their guesses solely on the women’s girth. Even when the researchers inflated the actual height of the woman by as much as 10 inches, it didn’t alter the participants’ weight estimates.
Similarly, participants simply assumed the portion sizes in the meals they were shown were typical, and guessed no caloric differences between small and large portions.
The study, published in the June issue of the Journal of Experimental Psychology-Applied, suggests that far from using logical thinking to deduce the weight of the women or the calorie content of the meal, the students simply devalued or ignored critical information.
According to the researchers, these results are an example of what they call “negative artifacts” from the brain’s evolution. Our brains, the psychologists say, have evolved to free up our conscious thinking for when it’s really needed—to face sudden danger, for instance. So, rather than taking up consciousness to cycle through a series of decisions for everything we do, our brains simply jump to the easiest conclusion without bothering to think at all.
The example the Pennsylvania researchers give is stopping at a stoplight. When the light turns green, we go, without thinking about it.
“We have heuristics in our brain—simple mechanistic shortcuts that have evolved over hundreds of thousands of years, which free up precious space in our consciousness,” is how Andrew Geier, lead author of the study, puts it. “In these atypical instances, however, it’s the shortcut that hurts us.”
Consider that green-light scenario. Most of the time, the go-means-green shortcut is fine, and at least keeps you from getting honked at by the guy in the rusted-out beater with the extra-loud stereo system behind you. But if you rely too much on that shortcut, and fail to look both ways before pulling into the intersection at the changing of the light, you may get smacked by some driver—probably the first cousin of that annoying guy behind you—whose own built-in shortcut is “yellow means drive really fast.”
These shortcuts may also be contributing to the growing girth of North Americans. For most of human existence, food has been scarce, and so whenever you had it, you ate it. As a result, we have a built-in cognitive shortcut that drives us, in the presence of abundance—say, the hotel breakfast buffet—to eat far more than we need, and even to see our laden plates as simply a normal-sized breakfast instead of enough calories to meet our energy needs for the entire day.
Worse, we see it that way even though we know, intellectually, the approximate calorie content of eight pieces of bacon, two pieces of French toast slathered in syrup, a mound of scrambled eggs, a Danish and a tall glass of orange juice (somewhere around 1,100, by my count).
Or, as Geir puts it, “The eating environment has morphed into an atypical scenario where our usually helpful mental mechanisms betray us.”
Food for thought…which reminds me; I can’t write on an empty stomach.
I wonder what’s in the fridge?
