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from the publisher:
A seminal book by one of the world's foremost memory experts offers the first framework that explains common memory vices -- and their surprising virtues.
Daniel L. Schacter, chairman of Harvard University’s Psychology Department and a leading expert on memory, has developed the first framework that describes the basic memory miscues we all encounter. Just like the seven deadly sins, the seven memory sins appear routinely in everyday life. Schacter explains how transience reflects a weakening of memory over time, how absent-mindedness occurs when failures of attention sabotage memory, and how blocking happens when we can't retrieve a name we know well. Three other sins involve distorted memories: misattribution (assigning a memory to the wrong source), suggestibility (implanting false memories), and bias (rewriting the past based on present beliefs). The seventh sin, persistence, concerns intrusive recollections that we cannot forget -- even when we wish we could. Although these sins may cause difficulties, as Schacter notes, they're surprisingly vital to a keen mind.
Schacter, whose previous trade book, Searching for Memory, was called "splendidly lucid" (The New Yorker), offers vivid examples of the memory sins -- for instance, the absent-mindedness that plagued both a national memory champion and a violinist who forgot that he had placed a priceless Stradivarius on top of his car before driving off. The author also delves into the recent research -- such as imaging that shows memories being formed in the brain -- which has led him to develop his framework. Together, the stories and the scientific findings examined in The Seven Sins of Memory provide a fascinating new look at our brains, and at what we more generally think of as our minds.
The Seven Sins of Memory is a groundbreaking work that will provide great reassurance to everyone, from twenty-somethings who find their lives are too busy, to baby boomers who mutter about "early Alzheimer’s," to senior citizens who worry about how much (or how little) they can recall.
Daniel L. Schacter is chairman of the Psychology Department at Harvard University. He has previously written Searching for Memory, which received praise as a New York Times Notable Book and a Library Journal Best Science and Technology Book of the Year, and won the American Psychological Association’s William James Book Award. He lives in Newton, Massachusetts.
"To a very great extent, our memories are our selves. The Seven Sins of Memory is a gripping and thought-provoking exploration of this eternally fascinating topic. Written by one of the world's experts, it presents startling examples from the news and everyday life and explains them using an original and elegant theory. The ideas are fascinating, and of great importance both for self-knowledge and for intelligent public policy." --Steven Pinker, professor of psychology at MIT and author of Words and Rules and How the Mind WorksThe following is an excerpt from the book The Seven Sins of Memory: How the Mind Forgets and Remembers by Daniel Schacter."Bravo: a tour de force. No one can better explain for the general reader the new insights on memory and its distortion than Daniel Schacter, one of the most exciting and original students of the biology of memory." --Eric R. Kandal, M.D., University Professor at Columbia University, senior investigator at the Howard Hughes Medical Institute, and 2000 Nobel laureate
"Want to know what memory is, how it works, and how to work around its failures? Read this book! Seven Sins commits none." --Joseph LeDoux, Henry and Lucy Moses Professor of Science, Center for Neural Science, New York University, and author of The Emotional Brain
"Schacter bestows on us a rare gift -- a fascinating journey through paths of memory, its open avenues and blind alleys. With sparkling prose and lively narratives, he challenges us to reconceive apparent defects of memory as crucial assets in successfully sustaining a sharp and productive mind. Rarely have I received such a lucid, engaging, and enjoyable book about science." --Jerome Groopman, M.D., professor of medicine at Harvard Medical School, staff writer at The New Yorker, and author of The Measure of Our Days and Second Opinions
INTRODUCTION:
A Blessing Bestowed by the Gods
In Yasunari Kawabata’s unsettling short story "Yumiura," a novelist receives an unexpected visit from a woman who says she knew him thirty years earlier. They met when he visited the town of Yumiura during a harbor festival, the woman explains. But the novelist cannot remember her. Plagued recently by other troublesome memory lapses, he sees this latest incident as a further sign of mental decline. His discomfort turns to alarm when the woman offers more revelations about what happened one day when he visited her room. "You asked me to marry you," she recalls wistfully. The novelist reels while contemplating the magnitude of what he has forgotten. The woman explains that she has never forgotten their time together and feels continually burdened by her memories of him.
After she leaves, the shaken novelist searches maps for the town of Yumiura with the hope of triggering recall of the place and the reasons why he had gone there. But no maps or books list such a town. The novelist then realizes that he could not have been in the part of the country the woman described at the time she remembered. Though the woman believed that her detailed and heartfelt memories were accurate, they were entirely false.
Kawabata’s story dramatically illustrates different ways in which memory can get us into trouble. Sometimes we forget the past and at other times we distort it; some disturbing memories haunt us for years. Yet we also rely on memory to perform an astonishing variety of tasks in our everyday lives. Recalling conversations with friends or recollecting family vacations, remembering appointments and errands we need to run, calling up words that allow us to speak and understand others, remembering foods we like and dislike, acquiring the knowledge needed for a new job -- all depend, in one way or another, on memory. Memory plays such a pervasive role in our daily lives that we often take it for granted until an incident of forgetting or distortion demands our attention.
In this book I explore the nature of memory’s imperfections, present a new way to think about them, and consider how we can reduce or avoid their harmful effects. Memory’s errors have long fascinated scientists, and during the past decade they have come to occupy a prominent place in our society. With the aging of the baby boom generation, memory problems are increasingly common among this large sector of the population. A 1998 cover story in Newsweek proclaimed that memory has become the principal health concern of busy, stressed-out, and forgetful baby boomers -- and many others. Forgotten encounters, misplaced eyeglasses, and failures to recall the names of familiar faces are becoming regular occurrences for many adults who are busily trying to juggle the demands of work and family, and cope with the bewildering array of new communications technologies. How many passwords and PINs do you have to remember just to manage your affairs on the Internet, not to mention your voice mail at the office or your cell phone? Have you ever had to apply for a temporary PIN at a website because you’ve forgotten your permanent number? I certainly have.
In addition to dealing with the frustrations of memory failures in daily life, the awful specter of Alzheimer’s disease looms large. As the general public becomes ever more aware of its horrors through such high profile cases as Ronald Reagan’s battle with the disorder, the prospects of a life dominated by catastrophic forgetting further increase our preoccupations with memory.
Although the magnitude of the woman’s memory distortion in "Yumiura" seems to stretch the bounds of credulity, it has been equaled and even exceeded in everyday life. Consider the story of Binjimin Wilkomirski, whose 1996 Holocaust memoir, Fragments, won worldwide acclaim for portraying life in a concentration camp from the perspective of a child. Wilkomirski presented readers with raw, vivid recollections of the unspeakable terrors he witnessed as a young boy. His prose achieved such power and eloquence that one reviewer proclaimed that Fragments is "so morally important and so free from literary artifice of any kind at all that I wonder if I even have the right to try to offer praise." Even more remarkable, Wilkomirski had spent much of his adult life unaware of these traumatic childhood memories, coming to terms with them only in therapy. Because his story and memories inspired countless others, Wilkomirksi became a sought-after international figure and a hero to Holocaust survivors.
The story began to unravel, however, in late August 1998, when Daniel Ganzfried, a Swiss journalist and himself the son of a Holocaust survivor, published a stunning article in a Zurich newspaper. Ganzfried revealed that Wilkomirski is actually Bruno Dossekker, born in 1941 to a young woman named Yvone Berthe Grosjean, who later gave him up for adoption to an orphanage. Young Bruno spent all of the war years with his foster parents, the Dossekkers, in the safe confines of his native Switzerland. Whatever the basis for his traumatic "memories" of Nazi horrors, they did not come from childhood experiences in a concentration camp. Is Dossekker/Wilkomirksi simply a liar? Probably not: he still strongly believes that his recollections are real.
We’re all capable of distorting our pasts. Think back to your first year in high school and try to answer the following questions: Did your parents encourage you to be active in sports? Was religion helpful to you? Did you receive physical punishment as discipline? The Northwestern University psychiatrist Daniel Offer and his collaborators put these and related questions to sixty-seven men in their late forties. Their answers are especially interesting because Offer had asked the same men the same questions during freshman year in high school, thirty-four years earlier.
The men’s memories of their adolescent lives bore little relationship to what they had reported as high school freshmen. Fewer than 40 percent of the men recalled parental encouragement to be active in sports; some 60 percent had reported such encouragement as adolescents. Barely one-quarter recalled that religion was helpful, but nearly 70 percent had said that it was when they were adolescents. And though only one-third of the adults recalled receiving physical punishment decades earlier, as adolescents nearly 90 percent had answered the question affirmatively.
Memory’s errors are as fascinating as they are important. What sort of system permits the kinds of distortions described in Kawabata’s fiction and the Wilkomirski case, or the inaccuracies documented in Offer’s study? Why do we sometimes fail to recall the names of people whose faces are perfectly familiar to us? What accounts for episodes of misplaced keys, wallets, or similar lapses? Why do some experiences seem to disappear from our minds without a trace? Why do we repeatedly remember painful experiences we’d rather forget? And what can we do to avoid, prevent, or minimize these troublesome features of our memory systems?
Psychologists and neuroscientists have written numerous articles on specific aspects of forgetting or memory distortions, but no unified framework has conceptualized the various ways in which memory sometimes leads us astray. In this book, I provide such a framework. I try to develop a fresh approach to understanding the causes and consequences of memory’s imperfections that, for the first time, suggests a way to think about the wide range of problems that memory can create.
As a memory researcher for more than twenty years, I’ve long been intrigued by memory failures. But it was not until a sunny morning in May 1998, in the midst of my daily walk, that I considered a simple question: What are the different ways that memory can get us into trouble? I suddenly recognized that it is necessary to address that question in order to develop a broad understanding of memory errors. Yet I also realized that the question had not yet been asked. For the next few months, I brought together everything I knew about memory’s imperfections and attempted to impose some order on a vast array of lapses, mistakes, and distortions. I generated a variety of unsatisfactory schemes for conceptualizing these diverse observations, but eventually hit on a way of thinking that helped to make everything fall into place.
I propose that memory’s malfunctions can be divided into seven fundamental transgressions or "sins," which I call transience, absent-mindedness, blocking, misattribution, suggestibility, bias, and persistence. Just like the ancient seven deadly sins, the memory sins occur frequently in everyday life and can have serious consequences for all of us.
Transience, absent-mindedness, and blocking are sins of omission: we fail to bring to mind a desired fact, event, or idea. Transience refers to a weakening or loss of memory over time. It’s probably not difficult for you to remember now what you have been doing for the past several hours. But if I ask you about the same activities six weeks, six months, or six years from now, chances are you’ll remember less and less. Transience is a basic feature of memory, and the culprit in many memory problems.
Absent-mindedness involves a breakdown at the interface between attention and memory. Absent-minded memory errors -- misplacing keys or eyeglasses, or forgetting a lunch appointment -- typically occur because we are preoccupied with distracting issues or concerns, and don’t focus attention on what we need to remember. The desired information isn’t lost over time; it is either never registered in memory to begin with, or not sought after at the moment it is needed, because attention is focused elsewhere.
The third sin, blocking, entails a thwarted search for information that we may be desperately trying to retrieve. We’ve all failed to produce a name to accompany a familiar face. This frustrating experience happens even though we are attending carefully to the task at hand, and even though the desired name has not faded from our minds -- as we become acutely aware when we unexpectedly retrieve the blocked name hours or days later.
In contrast to these three sins of omission, the next four sins of misattribution, suggestibility, bias, and persistence are all sins of commission: some form of memory is present, but it is either incorrect or unwanted. The sin of misattribution involves assigning a memory to the wrong source: mistaking fantasy for reality, or incorrectly remembering that a friend told you a bit of trivia that you actually read about in a newspaper. Misattribution is far more common than most people realize, and has potentially profound implications in legal settings. The related sin of suggestibility refers to memories that are implanted as a result of leading questions, comments, or suggestions when a person is trying to call up a past experience. Like misattribution, suggestibility is especially relevant to -- and sometimes can wreak havoc within -- the legal system.
The sin of bias reflects the powerful influences of our current knowledge and beliefs on how we remember our pasts. We often edit or entirely rewrite our previous experiences -- unknowingly and unconsciously -- in light of what we now know or believe. The result can be a skewed rendering of a specific incident, or even of an extended period in our lives, which says more about how we feel now than about what happened then.
The seventh sin -- persistence -- entails repeated recall of disturbing information or events that we would prefer to banish from our minds altogether: remembering what we cannot forget, even though we wish that we could. Everyone is familiar with persistence to some degree: recall the last time that you suddenly awoke at 3:00 a.m., unable to keep out of your mind a painful blunder on the job or a disappointing result on an important exam. In more extreme cases of serious depression or traumatic experience, persistence can be disabling and even life-threatening.
In this book I consider new discoveries, some based on recent breakthroughs in neuroscience which allow us to see the brain in action as it learns and remembers and which are beginning to illuminate the basis of the seven sins. These studies allow us to see in a new light what’s going on inside our heads during the frustrating incidents of memory failure or error which can have a significant impact on our everyday lives. I also discuss how our emerging knowledge of the seven sins can help to counter them. But to understand the seven sins more deeply, we also need to ask why our memory systems have come to exhibit these bothersome and sometimes dangerous properties: Do the seven sins represent mistakes made by Mother Nature during the course of evolution? Is memory flawed in a way that has placed our species at unnecessary risk? I don’t think so. To the contrary, I contend that each of the seven sins is a by-product of otherwise desirable and adaptive features of the human mind.
Consider by analogy the ancient seven deadly sins. Pride, anger, envy, greed, gluttony, lust, and sloth have great potential to get us into trouble. Yet each of the deadly sins can be seen as an exaggeration of traits that are useful and sometimes necessary for survival. Gluttony may make us sick, but our health depends on consuming sufficient amounts of food. Lust can cost a straying husband his wife’s affections, but a sex drive is crucial for perpetuating genes. Anger might result in dangerous elevations of blood pressure, but also assures that we defend ourselves vigorously when threatened. And so forth.
I argue for a similar approach to the memory sins. Rather than portraying them as inherent weaknesses or flaws in system design, I suggest that they provide a window on the adaptive strengths of memory. The seven sins allow us to appreciate why memory works as well as it does most of the time, and why it evolved the design that it has. Though I focus on problems that the seven sins cause in everyday life, my purpose is not to ridicule or denigrate memory. Instead, I try to show why memory is a mainly reliable guide to our pasts and futures, though it sometimes lets us down in annoying but revealing ways.
I’ll begin by exploring the nature and consequences of the sin of transience in Chapter 1. Toward the close of the nineteenth century, pioneering psychologists first measured loss of retention over time and produced a famous curve of forgetting. Newer studies have taught us about what kinds of information are more or less susceptible to forgetting over time. This research has implications for such diverse topics as President Clinton’s grand jury testimony about what he recalled from meetings with Monica Lewinsky and Vernon Jordan, what you are likely to remember from a day at the office, and how forgetting changes with increasing age. We’ll also consider exciting new advances from state-of-the-art neuroimaging technologies, which provide snapshots of the brain in action as it learns and remembers. My research group has used neuroimaging to seek the roots of transience in brain activities that occur during the moments when a new memory is born. Insights into the basis of transience also suggest new methods to counter it. I’ll consider a range of approaches to reducing transience, including psychological techniques that promote enhanced encoding of new information, the effects of such popular products as Ginkgo biloba, and recent advances in neurobiology which are illuminating the genes that are responsible for remembering and forgetting. Chapter 2 focuses on the most irritating of the seven sins: absent-mindedness. We’ve all had more encounters with lost keys and forgotten errands than we might care to remember. Absent-minded errors have the potential to disrupt our lives significantly, as the great cellist Yo-Yo Ma found out in October 1999 when he left his $2.5 million instrument in the trunk of a taxi. Fortunately for Ma, police recovered the instrument right away. I’ll also consider a similar case with a bizarre outcome. To understand why absent-minded errors occur, we need to probe the interface between attention and memory, explore the role of cues and reminders in helping us to carry out everyday tasks, and understand the important role of automatic behavior in daily activities. We spend a great deal of our lives on autopilot, which helps us to perform routine tasks efficiently, but also renders us vulnerable to absent-minded errors. A new area of research on what psychologists call "prospective memory" is beginning to unravel how and why different types of absent-minded forgetting occur.
There are few more jarring experiences than knowing that you know something cold -- the name of an acquaintance or the answer to a trivia question -- while failing to produce the information when you need it. Chapter 3 explains why we are occasionally susceptible to such episodes of blocking. Proper names of people and places are especially vulnerable to blocking, and the reasons why this is so help to explain the basis of the sin of blocking. In a fascinating neurological disorder that I’ll consider, known as "proper name anomia," patients with damage to specific regions within the brain’s left hemisphere cannot retrieve proper names of people (and sometimes places), even though they can easily summon up the names of common objects. These patients often know a great deal about the people or places whose names they block, such as a person’s occupation or where a city is located on a map. The plight of these patients resembles the familiar tip-of-the-tongue state, where we can’t come up with a proper name or a common name, yet often can provide a great deal of information about it, including the initial letter and number of syllables. I’ll compare alternative theories of the tip-of-the tongue state and suggest ways to counter this and related forms of blocking.
Blocking also occurs when people try to remember personal experiences. I’ll consider exotic cases in which patients temporarily lose access to large sectors of their personal pasts, and new neuroimaging studies that are providing initial glimpses into what goes on in the brain during this sort of blocking. Laboratory studies of more mundane forms of blocking, in which retrieving some words from a recently read list impairs access to others, have intriguing implications for such real-world situations as interviewing eyewitnesses to a crime.
Chapter 4 considers the first of the sins of commission: misattribution. Sometimes we remember doing things we only imagined, or recall seeing someone at a particular time or place that differs from when or where we actually encountered him: we recall aspects of the event correctly, but misattribute them to the wrong source. I’ll show how misattribution errors figure prominently in such seemingly disparate phenomena as déjà vu, unintentional plagiarism, and cases of mistaken eyewitness identification. Remember the infamous John Doe 2 from the Oklahoma City bombing? I’ll explain why he was almost surely the product of a classic misattribution error.
Psychologists have devised clever methods for inducing powerful misattribution errors in the laboratory. People incorrectly claim -- often with great confidence -- having experienced events that have not happened. In addition to explaining why such false memories occur, I will explore a question with important practical and theoretical ramifications: is there any way to tell the differences between true and false memories? Our research team has used neuroimaging techniques to scan subjects while they experience true and false memories, and the results provide some insights into why false memories can be so subjectively compelling. We’ll also encounter brain-damaged patients who are especially prone to misattributions and false memories. One patient believed that he was "seeing film stars everywhere" -- mistaking unfamiliar faces for familiar ones. Understanding what has gone wrong in such individuals can help to illuminate the basis of misattributions in healthy people.
Chapter 5 examines what may well be the most dangerous of the seven sins: suggestibility. Our memories are sometimes permeable to outside influences: leading questions or feedback from other people can result in suggested false memories of events that never happened. Suggestibility is a special concern in legal contexts. We’ll examine cases where suggestive questioning by law enforcement officials has led to serious errors in eyewitness identification, and where suggestive procedures used by psychotherapists have elicited memories of traumatic events that never occurred. Young children are especially vulnerable to the influences of suggestive questioning, as illustrated in a tragic Massachusetts day care case in which an entire family went to prison because of children’s recollections that I believe have been tainted by suggestive questions. Suggestibility can also lead people to confess to crimes they did not commit. I’ll discuss such cases, and also consider recent experimental evidence showing that it is surprisingly easy to elicit false confessions in noncriminal settings.
As I showed in my earlier book, Searching for Memory, we tend to think of memories as snapshots from family albums that, if stored properly, could be retrieved in precisely the same condition in which they were put away. But we now know that we do not record our experiences the way a camera records them. Our memories work differently. We extract key elements from our experiences and store them. We then recreate or reconstruct our experiences rather than retrieve copies of them. Sometimes, in the process of reconstructing we add on feelings, beliefs, or even knowledge we obtained after the experience. In other words, we bias our memories of the past by attributing to them emotions or knowledge we acquired after the event.
Chapter 6 explores several different types of biases that sometimes skew our memories. For instance, "consistency biases" lead us to rewrite our past feelings and beliefs so that they resemble what we feel and believe now. We’ll see how consistency biases shape memories in diverse situations, ranging from how supporters of Ross Perot remembered feeling when he quit the 1992 presidential race to how much married and dating couples recall liking or loving each other at different points in the past. "Egocentric biases," in contrast, reveal that we often remember the past in a self-enhancing manner. I will show that egocentric biases can influence recall in diverse situations, ranging from how divorced couples recall their marital breakups to students’ recall of their anxiety levels prior to an exam. "Stereotypical biases" influence memories and perceptions in the social world. Experience with different groups of people leads to the development of stereotypes that capture their general properties, but can spawn inaccurate and unwarranted judgments about individuals. I’ll consider recent studies that explore how stereotypical bias fuels racial prejudice, and can even lead people to "remember" the names of nonexistent criminals. Although little is known about the brain systems that give rise to bias, I will discuss some intriguing clues from "split-brain" patients whose cerebral hemispheres have been disconnected from one another.
Chapter 7 focuses on the most debilitating of the seven sins: persistence. Try to think of the single biggest disappointment in your life -- a failure at work or school, or a romantic relationship gone sour. Chances are that you recollected this experience repeatedly in the days and weeks after it happened, even though you wished you could forget it. Persistence thrives in an emotional climate of depression and rumination, and can have profound consequences for psychological health, as we’ll see in the case of a baseball player who was literally haunted to death by the persisting memory of a single disastrous pitch. To understand the basis of persistence, I will consider evidence that emotions are closely linked with perception and registration of incoming information, which in turn influence the formation of new memories.
The force of persistence is greatest after traumatic experiences: wars, natural disasters, serious accidents, childhood abuse. Nearly everyone persistently remembers a traumatic event in its immediate aftermath, but only some people become "stuck in the past" for years or decades; we’ll explore why this is so. Traumatic memories can be so overwhelming that it is only natural to try to avoid reexperiencing them. Paradoxically, however, attempting to avoid remembering a trauma may only increase the long-term likelihood of persistently remembering it. Studies of brain structure and physiology are providing important information about the neural underpinnings of traumatic persistence, and also suggest potentially novel methods for reducing persistence.
After reading the first seven chapters, you might easily conclude that evolution burdened humankind with an extremely inefficient memory system -- so prone to error that it often jeopardizes our well-being. In Chapter 8 I take issue with this conclusion, and argue instead that the seven sins are by-products of otherwise adaptive properties of memory. For instance, I’ll show that transience makes memory adapt to important properties of the environment in which the memory system operates. I will also consider unusual cases of extraordinary recall which illustrate why some apparent limitations of memory that produce absent-mindedness are in fact desirable system properties. I’ll explain how misattribution arises because our memory systems encode information selectively and efficiently, rather than indiscriminately storing details, and examine how bias can facilitate psychological well-being. I’ll also argue that persistence is a price we pay for a memory system that -- much to our benefit -- gives high priority to remembering events that could threaten our survival. I draw on recent developments in evolutionary biology and psychology to place these suggestions in a broad conceptual context that allows us to appreciate better the possible origins of the seven sins.
In Kawabata’s "Yumiura," the woman who remembered a love affair that apparently never happened reflected on the gift of memory. "Memories are something we should be grateful for, don’t you think?" she asked the bemused novelist. "No matter what circumstances people end up in, they’re still able to remember things from the past -- I think it must be a blessing bestowed on us by the gods." She offered this high praise even though the memory system she celebrated led her unknowingly down a path of delusion. The path through this book is in some ways analogous: we will need to immerse ourselves in the dark sides of memory before we can fully appreciate this "blessing bestowed by the gods."
Copyright © 2001 Daniel Schacter
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