Kluge: The Haphazard Construction of the Human Mind

theme, such as old, wise, forgetful, and Florida, designed to elicit the concept of the elderly. The subjects did as they were told, diligently making their way through the task. The real experiment, however, didn’t begin until afterward, when Bargh surreptitiously videotaped subjects as they departed after the test, walking to an elevator down the hall. Remarkably, the words people read affected their walking speed. The subjects all presumably had places to go and people to see, but those who unscrambled words like retired and Florida ambled more slowly than those who hadn’t.

Another lab studied people as they played a trivia game. Those briefly primed by terms like professor or intelligent outperformed those prepped with less lofty expressions, such as soccer hooligans and stupid. All the trash-talking that basketball players do might be more effective than we imagine.

At first, these studies may seem like mere fun and games — stupid pet tricks for humans — but the real-life consequences of priming can be serious. For example, priming can lead minority groups to do worse when cultural stereotypes are made especially salient, and, other things being equal, negative racial stereotypes tend to be primed automatically even in well-intentioned people who report feeling “exactly the same” about whites and blacks. Likewise, priming may reinforce depression, because being in a bad mood primes a person to think about negative things, and this in turn furthers depression. The context-driven nature of memory may also play a role in leading depressed people to seek out depressive activities, such as drinking or listening to songs of lost love, which presumably deepens the gloom as well. So much for intelligent design.

Anchoring our memories in terms of context and cues, rather than specific pre-identified locations, leads to another problem: our memories often blur together. In the first instance, this means that something I learn now can easily interfere with something I knew before: today’s strawberry yogurt can obscure yesterday’s raspberry. Conversely, something I already know, or once knew, can interfere with something new, as in my trouble with acclimating to Rachel K.’s change in surname.

Ultimately, interference can lead to something even worse: false memories. Some of the first direct scientific evidence to establish the human vulnerability to false memories came from a now classic cognitive-psychology study in which people were asked to memorize a series of random dot patterns like these:

Later, the experimenters showed various dot patterns to the same subjects and asked whether they had seen certain ones before. People were often tricked by this next one, claiming they had seen it when in fact it is a new pattern, a sort of composite of the ones viewed previously.

We now know that these sorts of “false alarms” are common. Try, for example, to memorize the following list of words: bed, rest, awake, tired, dream, wake, snooze, blanket, doze, slumber, snore, nap, peace, yawn, drowsy, nurse, sick, lawyer, medicine, health, hospital, dentist, physician, ill, patient, office, stethoscope, surgeon, clinic, cure.

If you’re like most people, you’ll surely remember the categories of words I’ve just asked you to memorize, but you’ll probably find yourself fuzzy on the details. Do you recall the word dream or sleep (or both, or neither?), snooze or tired (or both, or neither)? How about doctor or dentist⁷. Experimental data show that most people are easily flummoxed, frequently falling for words they didn’t see (such as doctor). The same thing appears to happen even with so-called flashbulb memories, which capture events of considerable importance, like 9/11 or the fall of the Berlin Wall. As time passes, it becomes harder and harder to keep particular memories straight, even though we continue to believe, sometimes with great confidence, that they are accurate. Sadly, confidence is no measure of accuracy.

For most species, most of the time, remembering gist rather than detail is enough. If you are a beaver, you need to know how to build dams, but you don’t need to remember where each individual branch is. For most of evolution, the costs and benefits of context-dependent memory worked out fine: fast for gist, poor for detail; so be it.

If you are human, though, things are often different; societies and circumstances sometimes require of us a precision that wasn’t demanded of our ancestors. In the courtroom, for example, it’s not enough to know that some guy committed a crime; we need to know which guy did — which is often more than the average human can remember. Yet, until recently, with the rise of DNA evidence, eyewitness testimony has often been treated as the final arbiter; when an honest-looking witness appears confident, juries usually assume that this person speaks the truth.

Such trust is almost certainly misplaced — not because honest people lie, but because even the most honorable witness is just human— saddled with contextually driven memory. Oodles of evidence for this comes from the lab of the psychologist Elizabeth Loftus. In a typical study, Loftus shows her subjects a film of a car accident and asks them afterward what happened. Distortion and interference rule the day. For example, in one experiment, Loftus showed people slides of a car running a stop sign. Subjects who later heard mention of a yield sign would often blend what they saw with what they heard and misremember the car as driving past a yield sign rather than a stop sign.

In another experiment, Loftus asked several different groups of subjects (all of whom had seen a film of another car accident) slightly different questions, such as How fast were the cars going when they hit each other? or How fast were the cars going when they smashed into each other? All that varied from one version to the next was the final verb (hit, smashed, contacted, and so forth). Yet this slight difference in wording was enough to affect people’s memory: subjects who heard verbs like smashed estimated the crash as occurring at 40.8 miles per hour, a significantly greater speed than that reported by those who heard verbs with milder connotations, like hit (34.0) and contacted (31.8). The word smashed cues different memories than hit, subtly influencing people’s estimates.

Both studies confirm what most lawyers already know: questions can “lead witnesses.” This research also makes clear just how unreliable memory can be. As far as we can tell, this pattern holds just as strongly outside the lab. One recent real-world study, admittedly small, concerned people who had been wrongly imprisoned (and were subsequently cleared on the basis of DNA tests). Over 90 percent of their convictions had hinged on faulty eyewitness testimony.

When we consider the evolutionary origins of memory, we can start to understand this problem. Eyewitness testimony is unreliable because our memories are stored in bits and pieces; without a proper system for locating or keeping them together, context affects how well we retrieve them. Expecting human memory to have the fidelity of a video recorder (as juries often do) is patently unrealistic. Memories related to accidents and crimes are, like all memories, vulnerable to distortion.

A memorable line from George Orwell’s novel 1984 states that “Oceania had always been at war with Eurasia” — the irony being, of course, that until recently (in the time frame of the book) Oceania had not in fact been at war with Eurasia. (“As Winston well knew, it was only four years since Oceania had been at war with Eastasia and in alliance with Eurasia.”) The dictators of 1984 manipulate the masses by revising history. This idea is, of course, essential to the book, but when I read it as a smug teenager, I found the whole thing implausible: wouldn’t people remember that the battle lines only recently had been redrawn? Who was fooling whom?

Now I realize that Orwell’s conceit wasn’t so far-fetched. All memories — even those concerning our own history — are constantly being revised. Every time we access a memory, it becomes “labile,” subject to change, and this seems to be true even for memories that seem especially important and firmly established, such as those of political events or our own experiences.

A good, scientifically well documented illustration of how vulnerable autobiographical memory can be took place in 1992, courtesy of the ever-mercurial Ross Perot, an iconoclastic billionaire from Texas who ran for president as an independent candidate. Perot initially attracted a strong following, but suddenly, under fire, he withdrew from the race. At that point an enterprising psychologist named Linda Levine asked Perot followers how they felt about his withdrawal from the campaign. When Perot subsequently reentered the race, Levine had an unanticipated chance to collect follow-up data. Soon after election day, Levine asked people whom they voted for in the end, and how they felt about Perot earlier in the campaign, at the point when he had dropped out. Levine found