ch3
Chapter Three
Breaking Good Habits
The Effect of Context on Learning
Don’t forget your brain vitamins.
In college, that’s what passed for exam-taking advice, at least among those of us who frequented a hippified pill shop in downtown Boulder. There, on a shelf behind the counter, between vials of brown serum, lotus seeds, and hemp balm, were bottles of something called “Study Aid.” The label on the back listed herbs, root products, fiber, and “natural extracts.”
The not-so-secret ingredient was, most likely, speed.
One dose delivered a bump in confidence and motivation, along with a night of focused study time. That was the upside. The downside, after sequential doses, was a ragged withdrawal that dead-ended into a sudden, dreamless sleep—not ideal for operating heavy machinery, and a clear and present danger when sitting through a long exam. Close your eyes for a second and you were out, pencil clattering to the floor, liable to awake to the words, “Time’s up, please hand in your work.”
The don’t-forget-your-vitamins advice meant, above all, stay conscious. When in doubt, take an extra dose to cross the finish line. Over time, though, I began to wonder if there was something more to it. When I studied on a vitamin, I worked with a kind of silly abandon, talking to myself, pacing. And when it came time to take the test, I wanted some of that manic energy back. I wanted to hear the internal conversation, to have the same physical connection with the material. I began to think—we all did—that taking “Study Aid” right before the test made that connection happen. It wasn’t only keeping us upright; it made us feel mentally closer to what we’d studied, and as a result we thought we remembered more of it.
Did we actually know this to be true? No, of course not, we never tested it—we wouldn’t have known how if we’d wanted to. Yet we felt like we had a lucky charm, a way to put our head “in the same place” during test-taking as during studying. Essential it was, too, especially during finals week, with two and sometimes three tests falling on the same day. That kind of pressure drives people deep into their worst habits, whether chocolate and cigarettes, brain vitamins and nail-biting, cases of diet cola, or much stronger stuff. When hunkered down in this psychological survival mode, it can be a profound comfort to believe that a favorite “study aid” also improves exam performance. And so we did.
“Brain chemistry,” our theory went, “you want the same brain chemistry.”
For a long time afterward, I looked back on that kind of theorizing as pure rationalization, the undergraduate mind at its self-justifying finest. We had so many crackpot theories then, about dating and getting rich and studying, that I’d discarded the whole list. Still, millions of students have developed some version of the brain chemistry idea, and I think its enduring attraction is rooted in something deeper than wishful thinking. The theory fits in nicely with what we’ve been told about good study habits from Day 1—be consistent.
Consistency has been a hallmark of education manuals since the 1900s, and the principle is built into our every assumption about good study habits. Develop a ritual, a daily schedule, a single place and time set aside for study and nothing else. Find a private corner of the house or the library, and a quiet niche of the day, early or late. These ideas go back at least to the Puritans and their ideal of study as devotion, but they have not changed a whit. “Choose an area that is quiet and free from distractions,” begins a study guide from Baylor University, though it could be from any institution. It continues:
“Develop a study ritual to use each time you study.”
“Use earplugs or a headset to block out noise.”
“Say no to those who want to alter your study time.”
Et cetera. It is all about consistency.
And so is the “Study Aid” brain chemistry theory, if you think about it. Using the same “vitamin”—or, okay, mind-altering substance—to prepare and, later, to perform may not be particularly Puritan. But it’s nothing if not consistent.
It is also, within reason, correct.
Studying while seriously impaired is wasted time, in more ways than one, as millions of students have learned the hard way. Yet, generally speaking, we perform better on tests when in the same state of mind as when we studied—and, yes, that includes mild states of intoxication from alcohol or pot, as well as arousal from stimulants. Moods, preoccupations, and perceptions matter, too: how we feel while studying, where we are, what we see and hear. The scientific investigation into these influences—the inner mental context, so to speak, as well as the outer one—has revealed subtle dimensions of learning that we rarely, if ever, notice but can exploit to optimize our time. Along the way, paradoxically, this research has also demolished the consistency doctrine.
• • •
The story begins twenty feet underwater, just off the coast of Oban, Scotland.
Oban, on the Sound of Mull and facing the islands known as the Southern Hebrides, is a premier diving destination. It’s within easy range of the Rondo, an American steamer that sank here in 1934 and sits—jackknifed, nose-down—in 150 feet of water, a magnet for explorers in scuba gear. A half dozen other shipwrecks are also close—the Irish Thesis, lost in 1889; the Swedish Hispania, which went down in 1954—and the waters course with dogfish, octopus, cuttlefish, and the psychedelic sea slugs called nudibranchs.
It was here, in 1975, that a pair of psychologists from nearby Stirling University recruited a group of divers to participate in an unusual learning experiment.
The psychologists, D. R. Godden and A. D. Baddeley, wanted to test a hypothesis that many learning theorists favored: that people remember more of what they studied when they return to that same study environment. This is a variation on the detective novel line, “Now, Mrs. Higgins, let’s return to the night of the murder. Tell me exactly what you saw and heard.” Like the detective, psychologists hypothesized that features of the study location—the lighting, the wallpaper, the background music—provide the brain “cues” to shake free more information. The difference is that Mrs. Higgins is trying to revisit a dramatic scene, an autobiographical memory, and the researchers were applying the same idea—reinstatement, they called it—to facts, to what the Estonian psychologist Endel Tulving called “semantic memories.”
The idea seems far-fetched. Who on earth remembers what was playing through the headphones when he or she learned the definition of an isosceles triangle, or an ionic bond, or the role of Viola in Twelfth Night? And when Godden and Baddeley dreamed up their experiment, the evidence for reinstatement was shabby at best. In one previous experiment, for example, participants tried to memorize word lists they heard through earphones while standing with their heads inside a box containing multicolored flashing lights (two dropped out due to nausea). In another, subjects studied nonsense syllables while strapped to a board, which tipped on an axis like a teeter-totter, as in some cruel school yard prank.
The reinstatement seemed to facilitate better memory but Godden and Baddeley weren’t convinced. They wanted to test-drive reinstatement theory in an environment that was unusual but found in nature, not created by imaginative psychologists. So they had a group of eighteen scuba divers study a list of thirty-six words while submerged twenty feet underwater. The researchers split the divers into two groups. An hour later, one group took a test on the words on dry land, while the others strapped on their equipment and took the test back down under, using a waterproof mike to communicate with those on land doing the scoring. The results indeed depended strongly on test location. The divers who took the test underwater did better than those who took it on land, remembering about 30 percent more words. That’s a lot, and the two psychologists concluded that, “recall is better if the environment of the original learning is reinstated.”
Maybe the bubbles streaming past the diving mask acted as a cue, accentuating the vowels in the studied words. Maybe it was the rhythmic bellows of the breath in the mouthpiece, or the weight of the tank, plus the sight of swarming nudibranchs. Or the fact that those semantic memories became part of an episodic one (learning while diving). Perhaps all of the above. Reinstatement seemed to work, anyway—for underwater learning.
The Oban experiment lent comfort and encouragement to what would become a somewhat haphazard exploration of the influence of context on memory. The study materials in these experiments were almost always word lists, or word pairs, and the tests were usually on free recall. In one investigation, for example, people who studied a list of nonsense syllables on blue-gray cards remembered 20 percent more of them on a later test when the test cards were also blue-gray (as opposed to, say, red). In another, students who got exam questions from the same instructor who taught the material did 10 percent better than getting them from a neutral test proctor.
A psychologist named Steven M. Smith performed some of the most interesting experiments in this area, and it’s worth looking at one of his in detail to see how scientists measure and think about so-called contextual cues. In 1985 Smith, at Texas A&M University, convened a group of fifty-four Psych 101 students—psychologists’ standard guinea pigs—and had them study a list of forty words. He divided the students into three groups. One group studied in silence. Another had a jazz number, Milt Jackson’s “People Make the World Go Around,” playing in the background. The third had Mozart’s Piano Concerto Number 24 in C Minor. The music was on when the subjects arrived in their assigned rooms, and they had no reason to believe it was relevant to the experiment. They spent ten minutes memorizing, and left.
The students returned to the study room two days later and, without warning, they were given a test to see how many words they could freely recall. This time, Smith changed the tune for many of them. He subdivided the three groups. Some who’d studied to jazz took the test with jazz again; others took it with the Mozart; and others in silence. Likewise for those who studied with Mozart or in silence: They tested either in the same condition, or one of the other two. Nothing else changed.
Nothing, that is, except their scores.
Smith found that those who studied with Milt Jackson playing and took the test with the same music recalled twenty-one words on average—twice as many as those who studied with Jackson and took the test to Mozart, or in silence. Similarly, those who studied with Mozart recalled nearly twice as many words with Mozart playing than in silence or with the jazz in the background.
The punch line: Of those who studied and tested in the same condition, the silence-silence group did the worst. They recalled, on average, about half the words that the jazz-jazz or classical-classical groups did (eleven versus twenty). This is bizarre, and it raised an unexpected question: Could quiet somehow be inhibiting memory? The answer was no. If it had, then those who’d studied with jazz would have done worse taking the test in silence than with Mozart (vice versa, for those who’d studied with classical). They hadn’t.
What to make of this, then? The higher test scores square with reinstatement theory: The background music weaves itself subconsciously into the fabric of stored memory. Cue up the same music, and more of those words are likely to resurface. The lower scores in the quiet room (after quiet study) are harder to explain. Smith argued that they may be due to an absence of cues to reinstate. The students “do not encode the absence of sound any more than they might encode the absence of any type of stimulus, such as pain or food,” he wrote. As a result the study environment is impoverished, compared to one with music in the background.
By themselves, experiments like Smith’s and the others don’t tell us how to study, of course. We can’t cue up our own personal soundtrack for an exam, and we certainly can’t retrofit the exam room with the same furniture, wallpaper, and ambience as where we studied. Even if we could, it’s not clear which cues are important or how strong they really are. Still, this research establishes a couple of points that are valuable in developing a study strategy. The first is that our assumptions about learning are suspect, if not wrong. Having something going on in the study environment, like music, is better than nothing (so much for sanctity of the quiet study room).
The second point is that the experience of studying has more dimensions than we notice, some of which can have an impact on retention. The contextual cues scientists describe—music, light, background colors—are annoyingly ephemeral, it’s true. They’re subconscious, usually untraceable. Nonetheless, it is possible to recognize them at work in our own lives. Think of an instance in which you do remember exactly where and when you learned something. I’m not talking about hearing you made the high school all-star team or got chosen prom queen, either. I mean a factual, academic, semantic memory, like who assassinated Archduke Franz Ferdinand, or how Socrates died and why.
For me, it’s a late night in 1982, when I was studying for a test in the university’s math building. The buildings were open all night back then, and you could walk in and take a classroom for yourself, spread out, use the blackboard, and no roommates bursting in with beer or other temptations. I did it all the time, and sometimes the only other person in the place was an old guy roaming the halls, disheveled but kindly, a former physics teacher. He would wander into my classroom occasionally and say something like, “Do you know why quartz is used in watches?” I would say no, and he would explain. He was legit, he knew his stuff, and one night he strolled in and asked whether I knew how to derive the Pythagorean theorem using geometric figures. I did not. The Pythagorean theorem, the most famous equation in math, states that adding the square of the two short sides of a right triangle equals the square of the longest side. It existed in my head as a2 + b2 = c2, and I have no idea where I was when I learned that.
On that night, however, I learned a simple way to derive it—a beautiful thing it is, too—and I still can see what the guy was wearing (blue slacks, up to his chest), hear his voice (barely, he mumbled), and recall precisely where on the board he drew the figure (lower left corner):
The proof is done by calculating the area of the large square (c squared) and making it equal to the sum of the figures inside: four triangles (area: ½ b x c times 4) plus the area of the little box ((a—b) squared). Try it. Simplify the right side of that equation and watch what you get. I remember it any time I sit alone in some classroom or conference room under dimmed fluorescent lights, like if I’ve arrived first for a meeting. Those cues bring back the memory of that night and the proof itself (although it takes some futzing to get the triangles in place).
Those are contextual cues, when they’re conscious and visible. The reason I can recall them is that they’re also part of a scene, an autobiographical memory. The science tells us that, at least when it comes to retention of new facts, the subconscious ones are valuable, too. Not always—when we’re submerged in analytical work, they’re negligible—and not necessarily all of them. Only sometimes. So what, though? When it comes to learning, we’ll take any edge we can get.
I recall something else about that night, too. Normally, when visited by the Ghost of Physics Past, I was not entirely patient. I had work to do. I could do without the lecture about the properties of quartz. That night, though, I’d finished most of my studying and was in an open, expansive mood. I was happy to sit and listen and even hear about how “physics students today, they don’t learn any of this …”
That mood was part of my “environment,” too, wasn’t it? It had to be—I remember it. I wouldn’t have sat still for the lesson otherwise. If psychologists’ theory about reinstating sights and sounds was correct, then they’d have to show that it applied to internal mental states as well—to jealousy, anxiety, grumpiness, confidence—the entire mix-tape of emotions running through our heads.
The question was, how?
• • •
No one who’s gone through a bad breakup while trying to be a student will doubt the impact of mood on learning. Moods color everything we do, and when they’re extreme they can determine what we remember. The clearest demonstration comes from psychiatry, and the study of bipolar disorder. People with this condition are the extreme athletes of the emotional realm. Their moods cycle between weeks or months of buoyant, manic activity and periods of dark, paralyzing depression, and they know too well that those cycles determine what they remember and what they don’t. “There is a particular kind of pain, elation, loneliness, and terror involved in this kind of madness,” wrote the psychologist Kay Redfield Jamison, who has a diagnosis of bipolar. “When you’re high it’s tremendous. The ideas and feelings are fast and frequent like shooting stars, and you follow them until you find better and brighter ones.… But, somewhere, this changes. The fast ideas are far too fast, and there are far too many; overwhelming confusion replaces clarity. Memory goes.”
Indeed, researchers showed in a 1974 study that people with bipolar disorder have state-dependent memory: They remember best what happened during manic phases when they’re again manic. And vice versa: When depressed, they recall events and concepts they’d learned when they were down. As the study’s authors put it, “associations or episodic events … can be regenerated more completely in a similar mood state than they can in a different mood state.”
Yet bipolar is an extraordinary condition, and learning scientists could hardly rely on it to measure the effects of emotion on the rest of us. For most people, moods come and go, coloring our experience rather than defining it. Their impact on memory, if significant at all, would be far weaker than for those with bipolar. And to measure this impact in a rigorous way would mean inducing the same mood in groups of people, reliably and continuously. That’s a tall order, so learning scientists began to focus not on moods per se but on the influence of differing “internal mental states.” Altered states.
This was the 1970s, after all, when hundreds of thousands of young people were experimenting with consciousness-altering drugs, primarily LSD and marijuana. These recreational users, many of them college students, weren’t interested in the effect of the drugs on their grades—they were enjoying themselves. Yet there were all sorts of rumors about the possible benefits of such substances on learning. Hallucinogens were said to be “mind-expanding,” capable of opening up new ways of thinking about the world. Pot allowed the brain to see connections it hadn’t before (often too many, resulting in late night sessions full of perfect nonsense). Clearly, altered states intensified experience; might they intensify memory?
The rigorous research into our inner study environment would begin with drugs—the recreational kind. And its primary sponsor was the U.S. government, which, beginning in the early 1970s, funded a string of experiments that might be called the Studying Under the Influence series. By then, a scattering of research reports had already appeared, suggesting that some drugs, like barbiturates and alcohol, could produce so-called state-dependent learning in modest amounts—the “Study Aid” effect. The government-backed researchers wanted to clarify the picture.
These experiments tended to follow a similar blueprint: Get people high and have them study something; then give them a test hours later—either after getting high again or after ingesting a placebo. We’ll take a close look at one of these studies, to show what serious scientists and serious stoners can do when they put their heads together. In 1975, a research team led by James Eric Eich of the National Institute of Mental Health set out to test the effect of pot on retention (word lists again), as well as learn something about how the drug alters what the brain does with newly studied information. The researchers recruited thirty college students and recent graduates, brought them into their lab, and gave each a joint. Half of the group got a real one and half got a “placebo marijuana cigarette,” which looked and smelled real but delivered no THC, the active drug. “The subjects took deep inhalations, maintained them for 15 seconds, and repeated this process every 60 seconds,” the authors wrote. “The entire cigarette was smoked, with the aid of a holder, usually in about eight minutes.” These were not novices. On average, the participants smoked pot about five times a week. Within twenty minutes, those who smoked the full-strength joint were moderately high, based on their own ratings and physical measures, like pulse rate. Those who smoked the placebo did not show the same physiological changes.
At this point, all thirty studied.
They were handed sheets of paper and given a minute and a half to try to commit to memory forty-eight words. The words appeared grouped by category—for example, “A type of vehicle—streetcar, bus, helicopter, train,” or “A musical instrument—cello, organ, trumpet, banjo.” The categories were part of the experimental manipulation. We all look for patterns when trying to memorize a long list of items, bunching together those that look or sound the same, or are somehow related. The scientists wanted to see whether smoking pot influenced these “higher-order” cues we use to retrieve information later on, so they provided the categories. When the ninety seconds were up, the papers were taken away.
Four hours later, when the effects of the drug had worn off, the participants returned to the lab and had another smoke. Some who’d been given a real joint the first time got a placebo this time around, and vice versa. Others smoked the same type both times. Twenty minutes later, without further study, they took a test.
Some got a free recall test, writing down as many of the words as they could remember in six minutes. Others took a “cued recall” test, in which they saw the list of categories (“A type of vehicle”) and filled in as many of the words in that category as they could. And sure enough—on the free recall—those who’d smoked a real joint on both occasions remembered 40 percent more than those who got a real one to study and a placebo for the test. The reverse was also true to a lesser extent: Those who initially studied on the placebo joint did better after smoking another placebo, compared to a real joint. The participants’ memories functioned best when their brain was in the same state during study as during testing, high or not high.
Why? The cued-recall test (the one with the categories) helped provide an answer. The scores on this test were uniformly high, no matter what the students smoked or when. This finding suggests that the brain stores roughly the same number of words when moderately high as when not—the words are in there, either way. Yet it must organize them in a different way for later retrieval. That “retrieval key” comes back most clearly when the brain is in the same state, stoned or sober. The key becomes superfluous, however, when the categories are printed right there on the page. There’s no need for it, because an external one is handy. As the authors wrote, “The accessibility of retrieval cues which have been encoded in drug associated state—such as that produced by a moderate dose of marijuana—appears to depend, in part, on restoration of that state at the time of desired recall.”
The joint-placebo study also gives us an idea how strong these internal, drug-induced memory cues are. Not so strong. Give someone a real hint—like a category name—and it easily trumps the internal cues. The same thing turned out to be true for alcohol and other drugs that these researchers and others eventually studied: Internal and external cues can be good reminders, but they pale next to strong hints.
The personality of the learning brain that emerges from all this work on external and internal cues is of a shifty-eyed dinner companion. It is tracking the main conversation (the homework assignment, the music notation, the hard facts) and occasionally becoming engaged in it. At the same time, it’s also periodically having a quick look around, taking in the room, sketching in sights and sounds and smells, as well as noting its internal reactions, its feelings and sensations. These features—the background music, a flickering candle, a pang of hunger—help our companion recall points made during the conversation later on, especially when the topic is a new one. Still, a strong hint is better.
I think about this, again, in terms of the geometric proof of the Pythagorean theorem. Summoning up that late night scene in the math building three decades ago, I can begin to reconstruct the proof, but as I said it takes some futzing to get the triangles in place. However, if someone sketches out just part of the drawing, it all comes back immediately. The strong hint provided by a partial drawing trumps the weaker ones provided by reinstating my learning environment.
In a world that provided strong hints when needed, this system would be ideal. Just as it would be wonderful if, whenever we had to perform on some test, we could easily re-create the precise environment in which we studied, piping in the same music that was playing, dialing up the same afternoon light, the same mental state—all of the internal and external features that were present when the brain stored the material in the first place.
I’ll say this for those “Study Aids”: I could control where, when, and how much, and I believe that the vitamins allowed me to heap more information into my fragile mind at the times when I most needed to. Stimulants and other substances become a psychological crutch for so many for the same reason that researchers used them in studies—they’re a quick and reliable way to reproduce a particular mental state.
But there’s a better way. There’s a way to exploit the effects of internal and external cues without having to bet on any single environment or rely on a drug to power through.
• • •
Take a look at the table below and see if you detect any patterns, any system to group the numbers and letters in memory:
Give up? You should. There aren’t any good storage patterns, because the man who put it together invented it that way. He designed it to be as challenging as possible to remember, a random collection.
In the mid-1920s, Alexander Luria, a neuropsychologist at the University of Moscow, was studying memory when he met a newspaper reporter named Solomon Shereshevsky. Shereshevsky had been working at a city paper and behaving in ways that made his editor suspicious. Every morning, the staff gathered to go through a long list of the coming day’s activities—the events, people, and potential stories the editor wanted tracked. The reporters all took careful notes, except for Shereshevsky, who didn’t even bring a notebook. The boss, convinced the reporter was slacking, confronted him on it.
I don’t need to take notes, Shereshevsky replied, I just remember. He proceeded to detail that morning’s long list of assignments, without error. Not only that day’s but the previous day’s meeting, and the one before that. He just remembered things, he said. This performance struck the editor as so extraordinary that he recommended that he go see Luria.
And so began a famous collaboration. For the next four decades, Luria tested and retested Shereshevsky—“S.,” as he called him in print to protect his identity—eventually producing a panoramic exploration of one of the largest, most precise memories the world has known. S.’s feats of memory seemed beyond explaining. He could study an entire matrix of random numbers for fifteen minutes and recall the entire thing a week—a month, even a decade—later.
He could do the same for lists of words, for poems, for short reading selections, in his native Russian and in languages that were completely foreign to him, like Italian. Luria’s extensive interviews with S. about his memory, detailed in his book The Mind of a Mnemonist, revealed that S. had a condition called synesthesia, in which perceptions are mixed and unusually vivid. Sounds have shapes, colors; letters have taste, fragrance. “Even numbers remind me of images,” S. told Luria. “Take the number one. This is a proud, well-built man. Two is a high-spirited woman, three a gloomy person … as for the number 87, what I see is a fat woman and a man twirling his mustache.” He attached an unusual number of cues to each thing he memorized, including internally generated images and details of the learning environment, like the sound of Luria’s voice.
Shereshevsky’s recall of words, numbers, and voices was so complete, in fact, that often one performance encroached on another performance, especially when they occurred in the same place, with no difference in context. He had to work to block related material. “Writing something down means I’ll know I won’t have to remember it,” he told Luria. “So I started doing this with small matters like phone numbers, last names, errands of one sort or another. But I got nowhere, for in my mind I continued to see what I’ve written.” He lacked a normal forgetting filter, and it often frustrated him.
Luria had Shereshevsky study one of his number-letter matrices on May 10, 1939. S. examined it for three minutes. After a short break, he could recite it without error, row by row, column by column, or along the diagonals. Several months later, Luria tested him again—without warning—on the same table. “The only difference in the two performances was that for the latter one he needed more time to ‘revive’ the entire situation in which the experiment had originally been carried out,” Luria wrote. “To ‘see’ the room in which we had been sitting; to ‘hear’ my voice; to ‘reproduce’ an image of himself looking at the board.” S. reinhabited the May 10 study session to bring back the matrix.
Shereshevsky was a prodigy, and his methods are largely off-limits to the rest of us. We can’t revive our study surroundings in nearly so much detail, and even if we could, there’s no chance that the entire table would scroll back up in pristine clarity. Our minds don’t work in the same way. Yet S.’s use of multiple perceptions—audio, visual, sensual—hints at how we can capitalize on context. We can easily multiply the number of perceptions connected to a given memory—most simply, by varying where we study.
How much could a simple change in venue aid recall?
In the mid-1970s, a trio of psychologists performed an experiment to answer that question. Steven Smith, Robert Bjork, and another psychologist, Arthur Glenberg, all then at the University of Michigan, wondered what would happen if people studied the same material twice, only in two different places. They presented a group of students with a list of forty four-letter words, like “ball” and “fork.” Half the students studied the words in two ten-minute sessions, a few hours apart, either in the same small, cluttered, basement room or in a neat windowed room looking out on a courtyard. The other half studied the words in two settings: once in that small, windowless room and again in the neat windowed one overlooking the courtyard. Two groups. The same words. In the same order. The same amount of time. One group in the same environment both times, the other in two distinct ones.
“I considered myself, the experimenter, part of the environment, too,” Smith told me. “In the windowless, basement room I looked like I usually did, long wild hair, flannel shirt, construction boots. In the modern conference room, I had my hair slicked back, I wore a tie, I had on the suit my dad wore to my bar mitzvah. Some of the students who studied in both places thought I was a different guy.”
After the second session the students rated each word on whether it evoked positive or negative associations. This was a ruse, to give them the impression that they were done with those words, that there was no reason to think about or practice them. In fact, they weren’t done. In the third phase of the experiment, three hours later, researchers had the students write down as many of the words as they could in ten minutes. This test occurred in a third, “neutral” room, a regular classroom. There was no reinstatement, as in previous context studies. The third room was one that the participants hadn’t been in before and was nothing like the other two where they had studied.
The difference in scores was striking. The one-room group recalled an average of sixteen of the forty studied words. The two-rooms group recalled twenty-four. A simple change in venue improved retrieval strength (memory) by 40 percent. Or, as the authors put it, the experiment “showed strong recall improvements with variation of environmental context.”
No one knows for sure why changing rooms could be better for recall than staying put. One possibility is that the brain encodes one subset of the words in one room, and a slightly different set in the other. Those two subsets overlap, and two subsets are better than one. Or it may be that rehearsing in two rooms doubles the number of contextual cues linked to any single word, fact, or idea being studied. In one room, the beige walls, fluorescent lighting, and clutter of stacked books color the memory of the word “fork”; in the other, “fork” is intertwined with the natural light pouring through the window, the sight of an old oak in the courtyard, the hum of an air conditioner. The material is embedded in two sensory layers, and that could give the brain at least one more opportunity to “revive” what it can of the study conditions and retrieve the words, or concepts. If Door Number 1 doesn’t work, it can try Door Number 2. We do this sort of perspective shifting all the time when, say, trying to remember the name of an actor. We pull up scenes from his most recent movie: There’s his face, but no name. We recall his face in the newspaper, his cameo on a TV show, maybe even a time we saw him onstage. We use multiple mental lenses to tease out the name and, in general, more detail.
Smith has since gone digital. He uses short video clips to create backgrounds, rather than herding students from room to room. In a typical experiment, he divides participants into two groups. One studies, say, twenty words in Swahili over five practice sessions of ten minutes each. The words appear on a movie screen, one at a time, transposed over a single, soundless background clip in all five sessions (of a train station, for example). This is the “same environment” condition. The other group studies the identical words, also over five ten-minute sessions, only those words appear over a different video background during each practice period (rainstorm, train station, desert scene, traffic jam, living room). A visual simulation, no more. Yet on tests taken two days later, the varied background group came out ahead, remembering an average of sixteen of the Swahili words, compared to nine or ten for the one-background group.
I have to admit I’m a sucker for this stuff. I love studies like these, because I can’t sit still for more than twenty minutes to study, if that. I want to believe that this kind of restlessness can deepen learning, and I often wish that the evidence for context variation was a little more … airtight.
The research has a meandering feel to it, to be honest. Scientists are still debating which cues matter most, when, and how strong they really are. Because context effects are subtle, they’re hard to reproduce in experiments. The definition of “context,” for that matter, is a moving target. If it includes moods, movement, and background music, it could by extension mean any change in the way we engage our vocabulary lists, history chapters, or Spanish homework. Think about it. Writing notes by hand is one kind of activity; typing them using a keyboard is another. The same goes for studying while standing up versus sitting down, versus running on a treadmill. Daniel Willingham, a leading authority on the application of learning techniques in classrooms, advises his own students, when they’re reviewing for an exam, not to work straight from their notes. “I tell them to put the notes aside and create an entirely new outline, reorganizing the material,” he told me. “It forces you to think about the material again, and in a different way.”
Isn’t how we do something part of the “environment,” too?
It is. Yet the larger message of context research is that, in the end, it doesn’t much matter which aspects of the environment you vary, so long as you vary what you can. The philosopher John Locke once described the case of a man who had learned to dance by practicing according to a strict ritual, always in the same room, which contained an old trunk. Unfortunately, wrote Locke, “the idea of this remarkable piece of household stuff had so mixed itself with the turns and steps of all his dances, that though in that chamber he could dance excellently well, yet it was only when that trunk was there; he could not perform well in any other place unless that or some other trunk had its due position in the room.”
This research says, take the trunk out of the room. Since we cannot predict the context in which we’ll have to perform, we’re better off varying the circumstances in which we prepare. We need to handle life’s pop quizzes, its spontaneous pickup games and jam sessions, and the traditional advice to establish a strict practice routine is no way to do so. On the contrary: Try another room altogether. Another time of day. Take the guitar outside, into the park, into the woods. Change cafés. Switch practice courts. Put on blues instead of classical. Each alteration of the routine further enriches the skills being rehearsed, making them sharper and more accessible for a longer period of time. This kind of experimenting itself reinforces learning, and makes what you know increasingly independent of your surroundings
Breaking Good Habits
The Effect of Context on Learning
Don’t forget your brain vitamins.
In college, that’s what passed for exam-taking advice, at least among those of us who frequented a hippified pill shop in downtown Boulder. There, on a shelf behind the counter, between vials of brown serum, lotus seeds, and hemp balm, were bottles of something called “Study Aid.” The label on the back listed herbs, root products, fiber, and “natural extracts.”
The not-so-secret ingredient was, most likely, speed.
One dose delivered a bump in confidence and motivation, along with a night of focused study time. That was the upside. The downside, after sequential doses, was a ragged withdrawal that dead-ended into a sudden, dreamless sleep—not ideal for operating heavy machinery, and a clear and present danger when sitting through a long exam. Close your eyes for a second and you were out, pencil clattering to the floor, liable to awake to the words, “Time’s up, please hand in your work.”
The don’t-forget-your-vitamins advice meant, above all, stay conscious. When in doubt, take an extra dose to cross the finish line. Over time, though, I began to wonder if there was something more to it. When I studied on a vitamin, I worked with a kind of silly abandon, talking to myself, pacing. And when it came time to take the test, I wanted some of that manic energy back. I wanted to hear the internal conversation, to have the same physical connection with the material. I began to think—we all did—that taking “Study Aid” right before the test made that connection happen. It wasn’t only keeping us upright; it made us feel mentally closer to what we’d studied, and as a result we thought we remembered more of it.
Did we actually know this to be true? No, of course not, we never tested it—we wouldn’t have known how if we’d wanted to. Yet we felt like we had a lucky charm, a way to put our head “in the same place” during test-taking as during studying. Essential it was, too, especially during finals week, with two and sometimes three tests falling on the same day. That kind of pressure drives people deep into their worst habits, whether chocolate and cigarettes, brain vitamins and nail-biting, cases of diet cola, or much stronger stuff. When hunkered down in this psychological survival mode, it can be a profound comfort to believe that a favorite “study aid” also improves exam performance. And so we did.
“Brain chemistry,” our theory went, “you want the same brain chemistry.”
For a long time afterward, I looked back on that kind of theorizing as pure rationalization, the undergraduate mind at its self-justifying finest. We had so many crackpot theories then, about dating and getting rich and studying, that I’d discarded the whole list. Still, millions of students have developed some version of the brain chemistry idea, and I think its enduring attraction is rooted in something deeper than wishful thinking. The theory fits in nicely with what we’ve been told about good study habits from Day 1—be consistent.
Consistency has been a hallmark of education manuals since the 1900s, and the principle is built into our every assumption about good study habits. Develop a ritual, a daily schedule, a single place and time set aside for study and nothing else. Find a private corner of the house or the library, and a quiet niche of the day, early or late. These ideas go back at least to the Puritans and their ideal of study as devotion, but they have not changed a whit. “Choose an area that is quiet and free from distractions,” begins a study guide from Baylor University, though it could be from any institution. It continues:
“Develop a study ritual to use each time you study.”
“Use earplugs or a headset to block out noise.”
“Say no to those who want to alter your study time.”
Et cetera. It is all about consistency.
And so is the “Study Aid” brain chemistry theory, if you think about it. Using the same “vitamin”—or, okay, mind-altering substance—to prepare and, later, to perform may not be particularly Puritan. But it’s nothing if not consistent.
It is also, within reason, correct.
Studying while seriously impaired is wasted time, in more ways than one, as millions of students have learned the hard way. Yet, generally speaking, we perform better on tests when in the same state of mind as when we studied—and, yes, that includes mild states of intoxication from alcohol or pot, as well as arousal from stimulants. Moods, preoccupations, and perceptions matter, too: how we feel while studying, where we are, what we see and hear. The scientific investigation into these influences—the inner mental context, so to speak, as well as the outer one—has revealed subtle dimensions of learning that we rarely, if ever, notice but can exploit to optimize our time. Along the way, paradoxically, this research has also demolished the consistency doctrine.
• • •
The story begins twenty feet underwater, just off the coast of Oban, Scotland.
Oban, on the Sound of Mull and facing the islands known as the Southern Hebrides, is a premier diving destination. It’s within easy range of the Rondo, an American steamer that sank here in 1934 and sits—jackknifed, nose-down—in 150 feet of water, a magnet for explorers in scuba gear. A half dozen other shipwrecks are also close—the Irish Thesis, lost in 1889; the Swedish Hispania, which went down in 1954—and the waters course with dogfish, octopus, cuttlefish, and the psychedelic sea slugs called nudibranchs.
It was here, in 1975, that a pair of psychologists from nearby Stirling University recruited a group of divers to participate in an unusual learning experiment.
The psychologists, D. R. Godden and A. D. Baddeley, wanted to test a hypothesis that many learning theorists favored: that people remember more of what they studied when they return to that same study environment. This is a variation on the detective novel line, “Now, Mrs. Higgins, let’s return to the night of the murder. Tell me exactly what you saw and heard.” Like the detective, psychologists hypothesized that features of the study location—the lighting, the wallpaper, the background music—provide the brain “cues” to shake free more information. The difference is that Mrs. Higgins is trying to revisit a dramatic scene, an autobiographical memory, and the researchers were applying the same idea—reinstatement, they called it—to facts, to what the Estonian psychologist Endel Tulving called “semantic memories.”
The idea seems far-fetched. Who on earth remembers what was playing through the headphones when he or she learned the definition of an isosceles triangle, or an ionic bond, or the role of Viola in Twelfth Night? And when Godden and Baddeley dreamed up their experiment, the evidence for reinstatement was shabby at best. In one previous experiment, for example, participants tried to memorize word lists they heard through earphones while standing with their heads inside a box containing multicolored flashing lights (two dropped out due to nausea). In another, subjects studied nonsense syllables while strapped to a board, which tipped on an axis like a teeter-totter, as in some cruel school yard prank.
The reinstatement seemed to facilitate better memory but Godden and Baddeley weren’t convinced. They wanted to test-drive reinstatement theory in an environment that was unusual but found in nature, not created by imaginative psychologists. So they had a group of eighteen scuba divers study a list of thirty-six words while submerged twenty feet underwater. The researchers split the divers into two groups. An hour later, one group took a test on the words on dry land, while the others strapped on their equipment and took the test back down under, using a waterproof mike to communicate with those on land doing the scoring. The results indeed depended strongly on test location. The divers who took the test underwater did better than those who took it on land, remembering about 30 percent more words. That’s a lot, and the two psychologists concluded that, “recall is better if the environment of the original learning is reinstated.”
Maybe the bubbles streaming past the diving mask acted as a cue, accentuating the vowels in the studied words. Maybe it was the rhythmic bellows of the breath in the mouthpiece, or the weight of the tank, plus the sight of swarming nudibranchs. Or the fact that those semantic memories became part of an episodic one (learning while diving). Perhaps all of the above. Reinstatement seemed to work, anyway—for underwater learning.
The Oban experiment lent comfort and encouragement to what would become a somewhat haphazard exploration of the influence of context on memory. The study materials in these experiments were almost always word lists, or word pairs, and the tests were usually on free recall. In one investigation, for example, people who studied a list of nonsense syllables on blue-gray cards remembered 20 percent more of them on a later test when the test cards were also blue-gray (as opposed to, say, red). In another, students who got exam questions from the same instructor who taught the material did 10 percent better than getting them from a neutral test proctor.
A psychologist named Steven M. Smith performed some of the most interesting experiments in this area, and it’s worth looking at one of his in detail to see how scientists measure and think about so-called contextual cues. In 1985 Smith, at Texas A&M University, convened a group of fifty-four Psych 101 students—psychologists’ standard guinea pigs—and had them study a list of forty words. He divided the students into three groups. One group studied in silence. Another had a jazz number, Milt Jackson’s “People Make the World Go Around,” playing in the background. The third had Mozart’s Piano Concerto Number 24 in C Minor. The music was on when the subjects arrived in their assigned rooms, and they had no reason to believe it was relevant to the experiment. They spent ten minutes memorizing, and left.
The students returned to the study room two days later and, without warning, they were given a test to see how many words they could freely recall. This time, Smith changed the tune for many of them. He subdivided the three groups. Some who’d studied to jazz took the test with jazz again; others took it with the Mozart; and others in silence. Likewise for those who studied with Mozart or in silence: They tested either in the same condition, or one of the other two. Nothing else changed.
Nothing, that is, except their scores.
Smith found that those who studied with Milt Jackson playing and took the test with the same music recalled twenty-one words on average—twice as many as those who studied with Jackson and took the test to Mozart, or in silence. Similarly, those who studied with Mozart recalled nearly twice as many words with Mozart playing than in silence or with the jazz in the background.
The punch line: Of those who studied and tested in the same condition, the silence-silence group did the worst. They recalled, on average, about half the words that the jazz-jazz or classical-classical groups did (eleven versus twenty). This is bizarre, and it raised an unexpected question: Could quiet somehow be inhibiting memory? The answer was no. If it had, then those who’d studied with jazz would have done worse taking the test in silence than with Mozart (vice versa, for those who’d studied with classical). They hadn’t.
What to make of this, then? The higher test scores square with reinstatement theory: The background music weaves itself subconsciously into the fabric of stored memory. Cue up the same music, and more of those words are likely to resurface. The lower scores in the quiet room (after quiet study) are harder to explain. Smith argued that they may be due to an absence of cues to reinstate. The students “do not encode the absence of sound any more than they might encode the absence of any type of stimulus, such as pain or food,” he wrote. As a result the study environment is impoverished, compared to one with music in the background.
By themselves, experiments like Smith’s and the others don’t tell us how to study, of course. We can’t cue up our own personal soundtrack for an exam, and we certainly can’t retrofit the exam room with the same furniture, wallpaper, and ambience as where we studied. Even if we could, it’s not clear which cues are important or how strong they really are. Still, this research establishes a couple of points that are valuable in developing a study strategy. The first is that our assumptions about learning are suspect, if not wrong. Having something going on in the study environment, like music, is better than nothing (so much for sanctity of the quiet study room).
The second point is that the experience of studying has more dimensions than we notice, some of which can have an impact on retention. The contextual cues scientists describe—music, light, background colors—are annoyingly ephemeral, it’s true. They’re subconscious, usually untraceable. Nonetheless, it is possible to recognize them at work in our own lives. Think of an instance in which you do remember exactly where and when you learned something. I’m not talking about hearing you made the high school all-star team or got chosen prom queen, either. I mean a factual, academic, semantic memory, like who assassinated Archduke Franz Ferdinand, or how Socrates died and why.
For me, it’s a late night in 1982, when I was studying for a test in the university’s math building. The buildings were open all night back then, and you could walk in and take a classroom for yourself, spread out, use the blackboard, and no roommates bursting in with beer or other temptations. I did it all the time, and sometimes the only other person in the place was an old guy roaming the halls, disheveled but kindly, a former physics teacher. He would wander into my classroom occasionally and say something like, “Do you know why quartz is used in watches?” I would say no, and he would explain. He was legit, he knew his stuff, and one night he strolled in and asked whether I knew how to derive the Pythagorean theorem using geometric figures. I did not. The Pythagorean theorem, the most famous equation in math, states that adding the square of the two short sides of a right triangle equals the square of the longest side. It existed in my head as a2 + b2 = c2, and I have no idea where I was when I learned that.
On that night, however, I learned a simple way to derive it—a beautiful thing it is, too—and I still can see what the guy was wearing (blue slacks, up to his chest), hear his voice (barely, he mumbled), and recall precisely where on the board he drew the figure (lower left corner):
The proof is done by calculating the area of the large square (c squared) and making it equal to the sum of the figures inside: four triangles (area: ½ b x c times 4) plus the area of the little box ((a—b) squared). Try it. Simplify the right side of that equation and watch what you get. I remember it any time I sit alone in some classroom or conference room under dimmed fluorescent lights, like if I’ve arrived first for a meeting. Those cues bring back the memory of that night and the proof itself (although it takes some futzing to get the triangles in place).
Those are contextual cues, when they’re conscious and visible. The reason I can recall them is that they’re also part of a scene, an autobiographical memory. The science tells us that, at least when it comes to retention of new facts, the subconscious ones are valuable, too. Not always—when we’re submerged in analytical work, they’re negligible—and not necessarily all of them. Only sometimes. So what, though? When it comes to learning, we’ll take any edge we can get.
I recall something else about that night, too. Normally, when visited by the Ghost of Physics Past, I was not entirely patient. I had work to do. I could do without the lecture about the properties of quartz. That night, though, I’d finished most of my studying and was in an open, expansive mood. I was happy to sit and listen and even hear about how “physics students today, they don’t learn any of this …”
That mood was part of my “environment,” too, wasn’t it? It had to be—I remember it. I wouldn’t have sat still for the lesson otherwise. If psychologists’ theory about reinstating sights and sounds was correct, then they’d have to show that it applied to internal mental states as well—to jealousy, anxiety, grumpiness, confidence—the entire mix-tape of emotions running through our heads.
The question was, how?
• • •
No one who’s gone through a bad breakup while trying to be a student will doubt the impact of mood on learning. Moods color everything we do, and when they’re extreme they can determine what we remember. The clearest demonstration comes from psychiatry, and the study of bipolar disorder. People with this condition are the extreme athletes of the emotional realm. Their moods cycle between weeks or months of buoyant, manic activity and periods of dark, paralyzing depression, and they know too well that those cycles determine what they remember and what they don’t. “There is a particular kind of pain, elation, loneliness, and terror involved in this kind of madness,” wrote the psychologist Kay Redfield Jamison, who has a diagnosis of bipolar. “When you’re high it’s tremendous. The ideas and feelings are fast and frequent like shooting stars, and you follow them until you find better and brighter ones.… But, somewhere, this changes. The fast ideas are far too fast, and there are far too many; overwhelming confusion replaces clarity. Memory goes.”
Indeed, researchers showed in a 1974 study that people with bipolar disorder have state-dependent memory: They remember best what happened during manic phases when they’re again manic. And vice versa: When depressed, they recall events and concepts they’d learned when they were down. As the study’s authors put it, “associations or episodic events … can be regenerated more completely in a similar mood state than they can in a different mood state.”
Yet bipolar is an extraordinary condition, and learning scientists could hardly rely on it to measure the effects of emotion on the rest of us. For most people, moods come and go, coloring our experience rather than defining it. Their impact on memory, if significant at all, would be far weaker than for those with bipolar. And to measure this impact in a rigorous way would mean inducing the same mood in groups of people, reliably and continuously. That’s a tall order, so learning scientists began to focus not on moods per se but on the influence of differing “internal mental states.” Altered states.
This was the 1970s, after all, when hundreds of thousands of young people were experimenting with consciousness-altering drugs, primarily LSD and marijuana. These recreational users, many of them college students, weren’t interested in the effect of the drugs on their grades—they were enjoying themselves. Yet there were all sorts of rumors about the possible benefits of such substances on learning. Hallucinogens were said to be “mind-expanding,” capable of opening up new ways of thinking about the world. Pot allowed the brain to see connections it hadn’t before (often too many, resulting in late night sessions full of perfect nonsense). Clearly, altered states intensified experience; might they intensify memory?
The rigorous research into our inner study environment would begin with drugs—the recreational kind. And its primary sponsor was the U.S. government, which, beginning in the early 1970s, funded a string of experiments that might be called the Studying Under the Influence series. By then, a scattering of research reports had already appeared, suggesting that some drugs, like barbiturates and alcohol, could produce so-called state-dependent learning in modest amounts—the “Study Aid” effect. The government-backed researchers wanted to clarify the picture.
These experiments tended to follow a similar blueprint: Get people high and have them study something; then give them a test hours later—either after getting high again or after ingesting a placebo. We’ll take a close look at one of these studies, to show what serious scientists and serious stoners can do when they put their heads together. In 1975, a research team led by James Eric Eich of the National Institute of Mental Health set out to test the effect of pot on retention (word lists again), as well as learn something about how the drug alters what the brain does with newly studied information. The researchers recruited thirty college students and recent graduates, brought them into their lab, and gave each a joint. Half of the group got a real one and half got a “placebo marijuana cigarette,” which looked and smelled real but delivered no THC, the active drug. “The subjects took deep inhalations, maintained them for 15 seconds, and repeated this process every 60 seconds,” the authors wrote. “The entire cigarette was smoked, with the aid of a holder, usually in about eight minutes.” These were not novices. On average, the participants smoked pot about five times a week. Within twenty minutes, those who smoked the full-strength joint were moderately high, based on their own ratings and physical measures, like pulse rate. Those who smoked the placebo did not show the same physiological changes.
At this point, all thirty studied.
They were handed sheets of paper and given a minute and a half to try to commit to memory forty-eight words. The words appeared grouped by category—for example, “A type of vehicle—streetcar, bus, helicopter, train,” or “A musical instrument—cello, organ, trumpet, banjo.” The categories were part of the experimental manipulation. We all look for patterns when trying to memorize a long list of items, bunching together those that look or sound the same, or are somehow related. The scientists wanted to see whether smoking pot influenced these “higher-order” cues we use to retrieve information later on, so they provided the categories. When the ninety seconds were up, the papers were taken away.
Four hours later, when the effects of the drug had worn off, the participants returned to the lab and had another smoke. Some who’d been given a real joint the first time got a placebo this time around, and vice versa. Others smoked the same type both times. Twenty minutes later, without further study, they took a test.
Some got a free recall test, writing down as many of the words as they could remember in six minutes. Others took a “cued recall” test, in which they saw the list of categories (“A type of vehicle”) and filled in as many of the words in that category as they could. And sure enough—on the free recall—those who’d smoked a real joint on both occasions remembered 40 percent more than those who got a real one to study and a placebo for the test. The reverse was also true to a lesser extent: Those who initially studied on the placebo joint did better after smoking another placebo, compared to a real joint. The participants’ memories functioned best when their brain was in the same state during study as during testing, high or not high.
Why? The cued-recall test (the one with the categories) helped provide an answer. The scores on this test were uniformly high, no matter what the students smoked or when. This finding suggests that the brain stores roughly the same number of words when moderately high as when not—the words are in there, either way. Yet it must organize them in a different way for later retrieval. That “retrieval key” comes back most clearly when the brain is in the same state, stoned or sober. The key becomes superfluous, however, when the categories are printed right there on the page. There’s no need for it, because an external one is handy. As the authors wrote, “The accessibility of retrieval cues which have been encoded in drug associated state—such as that produced by a moderate dose of marijuana—appears to depend, in part, on restoration of that state at the time of desired recall.”
The joint-placebo study also gives us an idea how strong these internal, drug-induced memory cues are. Not so strong. Give someone a real hint—like a category name—and it easily trumps the internal cues. The same thing turned out to be true for alcohol and other drugs that these researchers and others eventually studied: Internal and external cues can be good reminders, but they pale next to strong hints.
The personality of the learning brain that emerges from all this work on external and internal cues is of a shifty-eyed dinner companion. It is tracking the main conversation (the homework assignment, the music notation, the hard facts) and occasionally becoming engaged in it. At the same time, it’s also periodically having a quick look around, taking in the room, sketching in sights and sounds and smells, as well as noting its internal reactions, its feelings and sensations. These features—the background music, a flickering candle, a pang of hunger—help our companion recall points made during the conversation later on, especially when the topic is a new one. Still, a strong hint is better.
I think about this, again, in terms of the geometric proof of the Pythagorean theorem. Summoning up that late night scene in the math building three decades ago, I can begin to reconstruct the proof, but as I said it takes some futzing to get the triangles in place. However, if someone sketches out just part of the drawing, it all comes back immediately. The strong hint provided by a partial drawing trumps the weaker ones provided by reinstating my learning environment.
In a world that provided strong hints when needed, this system would be ideal. Just as it would be wonderful if, whenever we had to perform on some test, we could easily re-create the precise environment in which we studied, piping in the same music that was playing, dialing up the same afternoon light, the same mental state—all of the internal and external features that were present when the brain stored the material in the first place.
I’ll say this for those “Study Aids”: I could control where, when, and how much, and I believe that the vitamins allowed me to heap more information into my fragile mind at the times when I most needed to. Stimulants and other substances become a psychological crutch for so many for the same reason that researchers used them in studies—they’re a quick and reliable way to reproduce a particular mental state.
But there’s a better way. There’s a way to exploit the effects of internal and external cues without having to bet on any single environment or rely on a drug to power through.
• • •
Take a look at the table below and see if you detect any patterns, any system to group the numbers and letters in memory:
Give up? You should. There aren’t any good storage patterns, because the man who put it together invented it that way. He designed it to be as challenging as possible to remember, a random collection.
In the mid-1920s, Alexander Luria, a neuropsychologist at the University of Moscow, was studying memory when he met a newspaper reporter named Solomon Shereshevsky. Shereshevsky had been working at a city paper and behaving in ways that made his editor suspicious. Every morning, the staff gathered to go through a long list of the coming day’s activities—the events, people, and potential stories the editor wanted tracked. The reporters all took careful notes, except for Shereshevsky, who didn’t even bring a notebook. The boss, convinced the reporter was slacking, confronted him on it.
I don’t need to take notes, Shereshevsky replied, I just remember. He proceeded to detail that morning’s long list of assignments, without error. Not only that day’s but the previous day’s meeting, and the one before that. He just remembered things, he said. This performance struck the editor as so extraordinary that he recommended that he go see Luria.
And so began a famous collaboration. For the next four decades, Luria tested and retested Shereshevsky—“S.,” as he called him in print to protect his identity—eventually producing a panoramic exploration of one of the largest, most precise memories the world has known. S.’s feats of memory seemed beyond explaining. He could study an entire matrix of random numbers for fifteen minutes and recall the entire thing a week—a month, even a decade—later.
He could do the same for lists of words, for poems, for short reading selections, in his native Russian and in languages that were completely foreign to him, like Italian. Luria’s extensive interviews with S. about his memory, detailed in his book The Mind of a Mnemonist, revealed that S. had a condition called synesthesia, in which perceptions are mixed and unusually vivid. Sounds have shapes, colors; letters have taste, fragrance. “Even numbers remind me of images,” S. told Luria. “Take the number one. This is a proud, well-built man. Two is a high-spirited woman, three a gloomy person … as for the number 87, what I see is a fat woman and a man twirling his mustache.” He attached an unusual number of cues to each thing he memorized, including internally generated images and details of the learning environment, like the sound of Luria’s voice.
Shereshevsky’s recall of words, numbers, and voices was so complete, in fact, that often one performance encroached on another performance, especially when they occurred in the same place, with no difference in context. He had to work to block related material. “Writing something down means I’ll know I won’t have to remember it,” he told Luria. “So I started doing this with small matters like phone numbers, last names, errands of one sort or another. But I got nowhere, for in my mind I continued to see what I’ve written.” He lacked a normal forgetting filter, and it often frustrated him.
Luria had Shereshevsky study one of his number-letter matrices on May 10, 1939. S. examined it for three minutes. After a short break, he could recite it without error, row by row, column by column, or along the diagonals. Several months later, Luria tested him again—without warning—on the same table. “The only difference in the two performances was that for the latter one he needed more time to ‘revive’ the entire situation in which the experiment had originally been carried out,” Luria wrote. “To ‘see’ the room in which we had been sitting; to ‘hear’ my voice; to ‘reproduce’ an image of himself looking at the board.” S. reinhabited the May 10 study session to bring back the matrix.
Shereshevsky was a prodigy, and his methods are largely off-limits to the rest of us. We can’t revive our study surroundings in nearly so much detail, and even if we could, there’s no chance that the entire table would scroll back up in pristine clarity. Our minds don’t work in the same way. Yet S.’s use of multiple perceptions—audio, visual, sensual—hints at how we can capitalize on context. We can easily multiply the number of perceptions connected to a given memory—most simply, by varying where we study.
How much could a simple change in venue aid recall?
In the mid-1970s, a trio of psychologists performed an experiment to answer that question. Steven Smith, Robert Bjork, and another psychologist, Arthur Glenberg, all then at the University of Michigan, wondered what would happen if people studied the same material twice, only in two different places. They presented a group of students with a list of forty four-letter words, like “ball” and “fork.” Half the students studied the words in two ten-minute sessions, a few hours apart, either in the same small, cluttered, basement room or in a neat windowed room looking out on a courtyard. The other half studied the words in two settings: once in that small, windowless room and again in the neat windowed one overlooking the courtyard. Two groups. The same words. In the same order. The same amount of time. One group in the same environment both times, the other in two distinct ones.
“I considered myself, the experimenter, part of the environment, too,” Smith told me. “In the windowless, basement room I looked like I usually did, long wild hair, flannel shirt, construction boots. In the modern conference room, I had my hair slicked back, I wore a tie, I had on the suit my dad wore to my bar mitzvah. Some of the students who studied in both places thought I was a different guy.”
After the second session the students rated each word on whether it evoked positive or negative associations. This was a ruse, to give them the impression that they were done with those words, that there was no reason to think about or practice them. In fact, they weren’t done. In the third phase of the experiment, three hours later, researchers had the students write down as many of the words as they could in ten minutes. This test occurred in a third, “neutral” room, a regular classroom. There was no reinstatement, as in previous context studies. The third room was one that the participants hadn’t been in before and was nothing like the other two where they had studied.
The difference in scores was striking. The one-room group recalled an average of sixteen of the forty studied words. The two-rooms group recalled twenty-four. A simple change in venue improved retrieval strength (memory) by 40 percent. Or, as the authors put it, the experiment “showed strong recall improvements with variation of environmental context.”
No one knows for sure why changing rooms could be better for recall than staying put. One possibility is that the brain encodes one subset of the words in one room, and a slightly different set in the other. Those two subsets overlap, and two subsets are better than one. Or it may be that rehearsing in two rooms doubles the number of contextual cues linked to any single word, fact, or idea being studied. In one room, the beige walls, fluorescent lighting, and clutter of stacked books color the memory of the word “fork”; in the other, “fork” is intertwined with the natural light pouring through the window, the sight of an old oak in the courtyard, the hum of an air conditioner. The material is embedded in two sensory layers, and that could give the brain at least one more opportunity to “revive” what it can of the study conditions and retrieve the words, or concepts. If Door Number 1 doesn’t work, it can try Door Number 2. We do this sort of perspective shifting all the time when, say, trying to remember the name of an actor. We pull up scenes from his most recent movie: There’s his face, but no name. We recall his face in the newspaper, his cameo on a TV show, maybe even a time we saw him onstage. We use multiple mental lenses to tease out the name and, in general, more detail.
Smith has since gone digital. He uses short video clips to create backgrounds, rather than herding students from room to room. In a typical experiment, he divides participants into two groups. One studies, say, twenty words in Swahili over five practice sessions of ten minutes each. The words appear on a movie screen, one at a time, transposed over a single, soundless background clip in all five sessions (of a train station, for example). This is the “same environment” condition. The other group studies the identical words, also over five ten-minute sessions, only those words appear over a different video background during each practice period (rainstorm, train station, desert scene, traffic jam, living room). A visual simulation, no more. Yet on tests taken two days later, the varied background group came out ahead, remembering an average of sixteen of the Swahili words, compared to nine or ten for the one-background group.
I have to admit I’m a sucker for this stuff. I love studies like these, because I can’t sit still for more than twenty minutes to study, if that. I want to believe that this kind of restlessness can deepen learning, and I often wish that the evidence for context variation was a little more … airtight.
The research has a meandering feel to it, to be honest. Scientists are still debating which cues matter most, when, and how strong they really are. Because context effects are subtle, they’re hard to reproduce in experiments. The definition of “context,” for that matter, is a moving target. If it includes moods, movement, and background music, it could by extension mean any change in the way we engage our vocabulary lists, history chapters, or Spanish homework. Think about it. Writing notes by hand is one kind of activity; typing them using a keyboard is another. The same goes for studying while standing up versus sitting down, versus running on a treadmill. Daniel Willingham, a leading authority on the application of learning techniques in classrooms, advises his own students, when they’re reviewing for an exam, not to work straight from their notes. “I tell them to put the notes aside and create an entirely new outline, reorganizing the material,” he told me. “It forces you to think about the material again, and in a different way.”
Isn’t how we do something part of the “environment,” too?
It is. Yet the larger message of context research is that, in the end, it doesn’t much matter which aspects of the environment you vary, so long as you vary what you can. The philosopher John Locke once described the case of a man who had learned to dance by practicing according to a strict ritual, always in the same room, which contained an old trunk. Unfortunately, wrote Locke, “the idea of this remarkable piece of household stuff had so mixed itself with the turns and steps of all his dances, that though in that chamber he could dance excellently well, yet it was only when that trunk was there; he could not perform well in any other place unless that or some other trunk had its due position in the room.”
This research says, take the trunk out of the room. Since we cannot predict the context in which we’ll have to perform, we’re better off varying the circumstances in which we prepare. We need to handle life’s pop quizzes, its spontaneous pickup games and jam sessions, and the traditional advice to establish a strict practice routine is no way to do so. On the contrary: Try another room altogether. Another time of day. Take the guitar outside, into the park, into the woods. Change cafés. Switch practice courts. Put on blues instead of classical. Each alteration of the routine further enriches the skills being rehearsed, making them sharper and more accessible for a longer period of time. This kind of experimenting itself reinforces learning, and makes what you know increasingly independent of your surroundings
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