I’ve always been fascinated by the menus at diners: possessing an almost biblical heft, their pages and pages often list hundreds of dishes, ranging from standard greasy spoon fare to more far-fetched house specialties like the clams casino that George Costanza, fatefully and regretfully, ordered on a whim at Monk’s. But while I love most diner food and would likely be content with nearly any dish on the menu, I find that when I’m confronted with so many choices I just can’t decide between disco fries and a cheeseburger. A recent study shows I’m not alone: scientists have a name for this phenomenon—“choice overload”—and the paralysis can have graver consequences than the level of heartburn your chosen meal will provoke.
Researchers at Caltech were inspired by a study conducted in California two decades ago. In that study, researchers set up a table offering free samples of jam to customers in a grocery store, at times setting out 24 flavors of jam and at other times only six. While the jam buffet of 24 flavors attracted more customers, it resulted in far few purchases of jam; shoppers who stopped at the table set with six jams were ten times more likely to pick a flavor and buy it. In a study published yesterday on ScienceDaily, researchers from Caltech’s departments of Behavioral Economics and Social and Decision Neuroscience dug deeper into that demonstration of “choice overload” in action, examining just how many options the brain is comfortable with when making a decision. The answer? Not many.
"Essentially, our eyes are bigger than our stomachs," Colin Camerer, one of the study’s authors, said in the report. "When we think about how many choices we want, we may not be mentally representing the frustrations of making the decision."
In other words, while many of us love the idea of a loaded, all-you-can-eat buffet, a lot of us have probably had the experience of finally lining up with our empty plate and then being unable to figure out whether we want a slice of carved ham, or a made-to-order omelet, or a blueberry muffin.
To examine this phenomenon, the researchers at Caltech presented volunteers with pictures of scenic landscapes that they could have printed on a piece of merchandise, such as a coffee mug. Each volunteer was offered a variety of sets of images, containing six, 12, or 24 pictures. They were asked to choose the landscape they wanted printed while a functional magnetic resonance imaging (fMRI) machine recorded activity in their brains.
The fMRI scans revealed brain activity in two regions while the participants were making their decisions: the anterior cingulate cortex (ACC), where the costs and benefits of decisions are weighed, and the striatum, an area of the brain responsible for determining value.
Brain activity in the volunteers, as recorded by the fMRI scans, was revealed to be highest in both regions in volunteers who had 12 images to pick from, and lowest in those with either six or 24 images. That pattern of activity, Camerer said, is likely the result of the striatum and the ACC working together to weigh the increasing potential for reward—getting an image they really like for their mug—against the increasing amount of work the brain will have to do to evaluate possible outcomes.
As the number of options increases, the potential reward increases, but then begins to level off due to diminishing returns.
"The idea is that the best out of 12 is probably rather good, while the jump to the best out of 24 is not a big improvement," Camerer said.
Simultaneously, the amount of effort required to evaluate the options increases. Together, mental effort and the potential reward result in a “sweet spot” where the reward isn't too low and the effort isn't too high. Camerer estimated that depending the person and on the reward, an ideal number of options is probably somewhere between eight and 15—far fewer than the hundreds listed on that diner menu.
While selecting a jam or even an entrée isn’t a very high-stakes decision, “choice overload” can have some very real consequences. As the summary in ScienceDaily points out, when Sweden partially privatized its social security system in 1998, citizens were allowed to move some of their retirement savings into private funds. The government gave them hundreds of options, and ran a large advertising campaign encouraging them to choose their own funds. Initially, almost 70 percent of the adult population actively chose a fund, but the percentage quickly dropped off. After ten years, only about 1 percent of newly eligible Swedes were making an active decision about where to put their retirement money: it was just too much to think about.
And that’s how I feel every time I go to a diner: like an elderly Swede trying, but floundering, to safeguard my wealth.