7. The Sin of Persistence.

7. The Sin of Persistence.

ON A SUNNY AFTERNOON in early October 1986, a jubilant crowd of baseball fans cheered as the hometown California Angels neared victory ver the Boston Red Sox in the American League championship series. In he ninth inning of the series' fifth game, the Angels held a seemingly insurmountable advantage: leading by a score of 5 to 2, they needed only one
more win to clinch the series. But the Red Sox rallied, cutting the lead to 5 to 4 and putting a runner on first base with two outs. Trying to end the game, the Angels manager Gene Mauch summoned the ace reliever Donnie Moore from the bullpen to face the journeyman outfielder Dave Henderson. Moore quickly threw two strikes. Angels fans and players began to celebrate as the seemingly overmatched Henderson barely fouled off a pitch to
avoid striking out. With the odds stacked heavily against him, Henderson hammered Moore's next offering into deep left field for a game-winning home run. Moore, his teammates, and the crowd watched in disbelief as
Henderson trotted around the bases. The Angels failed to bounce back and the Red Sox advanced to the World Series.

With the passing of time, Angels players and fans eventually recovered from the deflating loss. But Donnie Moore never did. He was haunted, sometimes overwhelmed, by the memory of Henderson's home run.
Though his teammates tried to remind him of all the games he had saved during the season, Moore focused only on the fateful pitch, blaming himself for the team's defeat. Fans and media helped to strengthen the vivid
recollection by talking about the incident incessantly. Unable to shake the memory, Moore sank into an ever-deepening depression that undermined
his marriage and career. In July 1989, Moore's descent concluded violently. "Tormented by the memory of one pitch:' began a bulletin from the Associated Press, "and despondent over his failing career and marital troubles,
former California Angels pitcher Donnie Moore shot his wife numerous times before killing himself, police said:' Moore's agent, Dave Pinter, com mented that "Even when he was told that one pitch doesn't make a season, he couldn't get over it. That home run killed him."

Though Moore's downfall was probably not entirely attributable to this single incident, his demise nonetheless provides a dramatic example of
memory's seventh and perhaps most debilitating sin: persistence. In contrast to transience, absent-mindedness, and blocking, which entail forgetting information or events you wish you could remember, persistence
involves remembering those things that you wish you could forget. Sometimes, persistence is no more than a mild irritant. We've all had the experience of a tune or a song that we can't get out of our heads. We may at first
enjoy the experience, but as time goes on we tire of mentally "hearing" the persisting melody and attempt to banish the intruder from consciousness.
Sometimes these persistent memories can distract us from more important tasks. I recall feeling flustered as a high school student when a favorite Led
Zeppelin song kept running through my head in the middle of an exam, making concentration on the test almost impossible. Laurie Gordon, an
undergraduate in one of my Harvard seminars, recounted a similar annoyance and took steps to prevent its recurrence:

I was able to bring in a double-sided review sheet for one of my finals. I found that I had extra room on the sheet, since there wasn't much in ormation that would be useful to have during the exam. I decided to fill the extra space on the sheet with lyrics from 5 or so of my favorite
songs, so that I wouldn't run into the situation I had experienced the day before, when I had had difficulty concentrating because of an annoying song running through my head. Instead, when I took the exam,

I was able to block out this song by looking at the song lyrics that I had written on my review sheet.

Though irritating, the "tune-running-through-the-head" experience occurs relatively infrequently, most often does not have serious consequences, and can be managed effectively with techniques such as the one
that Gordon used. The type of persistence that overwhelmed Donnie Moore is far more troubling. Despite the extraordinary nature of Moore's
story, it nevertheless illuminates the primary territory of persistence: disappointment, regret, failure, sadness, and trauma. Experiences that we remember intrusively, despite desperately wanting to banish them from our
minds, are closely linked to, and sometimes threaten, our perceptions of who we are and who we would like to be.

HOT MEMORIES.

Because persistence is strongly linked with our emotional lives, to understand the seventh sin we need to consider the relationship between emotion and memory. Everyday experience and laboratory studies reveal that
emotionally charged incidents are better remembered than nonemotional events. The emotional boost begins at the moment that a memory is born,
when attention and elaboration strongly influence whether an experience will be subsequently remembered or forgotten. As bouts of absent-mindedness illustrate, when we fail to attend to or eiaboratively encode incoming
information we stand little chance of remembering it later.

Experiments have shown that emotional information attracts attention quickly and automatically, illustrated nicely by experiments using a
variant of the famous "Stroop effect:' Write the word yellow in a yellow color, red in a blue color, green in a black color, and try to name the color in
which each of the words is printed. You will notice that you take longer to say "blue" and "black" than "yellow:' because you can't help but analyze the
meanings of red and green, which conflict with the colors you are trying to name. Something similar can happen with emotional words such as sad
and joy: compared with neutral words like wet, naming the colors of positive and negative words takes longer. The emotional words seem to draw attention automatically, which gets in the way of naming the color. In the
split second that it takes to read a word, its emotional significance is retrieved and evaluated, influencing how we name and encode it.

After this first-pass automatic evaluation, the significance of emotional information undergoes evaluation in relation to our current goals
and concerns. Goals may be short-term - striking out a batter to end a baseball game - or long-term, such as performing well during the course
of a baseball season to attain a higher future salary. When our actions prevent us from attaining our goals - as with Donnie Moore, we feel sadness, frustration, or disappointment. When they allow us to attain our
goals - imagine that Moore had struck out Dave Henderson we feel happiness and perhaps elation. When we relate a current experience to
short- or long-term goals, we engage in a kind of reflection and analysiselaborative encoding - that promotes subsequent memory for the experience.

Though memory for emotional events generally benefits from both automatic first-pass evaluation and later reflections, there's a cost. Consider
a bystander in a bank as a robbery unfolds. Attempting to escape, the crook brandishes a gun; feeling a rush of fear, the bystander instantly focuses on
the weapon. Consequently, she can later recall the gun's features in great detail. But when police ask for a description of the robber, the bystander
can summon only a hazy memory of his face - not enough information to help investigators. Psychologists call this phenomenon "weapon focus."
The emotionally arousing object draws attention automatically, leaving few resources to help encode the rest of the scene. Experiments have shown that
people usually remember well the central focus of an emotionally arousing incident, at the expense of poor memory for peripheral details.

The benefits of emotional arousal for subsequent memory extend to
both positive and negative events: we remember more high and low moments from our lives than mundane ones. And positive experiences, just
like negative experiences, tend to be remembered involuntarily and intrusively. Roughly 90 percent of college students who recorded emotional incidents in a diary reported that they later experienced at least some intrusive memories for both positive and negative events, with more intense
emotions producing more frequent intrusive memories. The difference,
of course, is that positive memories are usually welcome intruders - we
enjoy basking in the glow of a recent business success, athletic accomplishment, or romantic encounter - whereas negative memories are decidedly
not.

Psychologists have long debated whether positive experiences are
better remembered than negative ones, or vice versa. Though little such evidence has turned up so far, experiments conducted in my laboratory by
the psychologist Kevin Ochsner have revealed an intriguing qualitative difference between the two. He showed college students a series of positive,
negative, and neutral photographs, such as a smiling baby, a disfigured face,
or an ordinary building. On a later test, people recognized more of the
positive and negative pictures than the neutral ones, and recognized about
the same number of positive as negative items. But when Ochsner probed
the experimental participants more closely about why they claimed to
recognize a particular picture, differences between positive and negative
memories began to emerge. When people recognized positive pictures, they
tended to say that the pictures just seemed familiar; when they recognized
negative pictures, they reported detailed, specific recollections of what they
thought and felt when they originally encountered the item. If we tend to
remember negative events in greater detail than positive ones, then we may be at special risk for persistently retrieving painful particulars of those experiences we would like most to forget.

WHEN MEMORY HURTS.

Our chances of becoming chronically plagued by persistence depend in
part on what happens after an adverse experience. Over time, the sting associated with unpleasant events often fades. We've all endured difficult experiences the death of a loved one, rejection by a lover, failure at work
- that pain us mightily in the days and weeks after they occur. In the immediate aftermath, we may find ourselves reliving the painful incident to
the point of distraction, but the raw hurt eventually dissipates. Recent data
suggest that negative emotions may actually fade faster than positive ones.
Consider a study in which college students kept diaries of daily experiences,
rated the pleasantness and other features of the events, and then tried to remember the experiences and associated emotions at various times ranging
from three months to over four years after the incident occurred. Memory
for unpleasant emotions faded faster than memory for pleasant emotions.

Reminders of difficult experiences can slow the normal fading of
painful emotions over time. The great novelist Gabriel Garda Marquez
began his novel Love in the Time of Cholera with a tribute to one: "It was inevitable: the scent of bitter almonds always reminded him of the fate of
unrequited love:' Continual reminding can strengthen recall of the disturbing specifics of what happened to a point at which persistence becomes
unbearable. Reporters, fans, and the media hounded Donnie Moore for
months after Henderson's home run, making it impossible for him to find
relief in the usual benefits conferred by the passing of time. His teammate
Brian Downing blamed the media for reminding Moore unrelentingly.
"You destroyed a man's life over one pitch:' commented Downing ruefully
after learning of Moore's suicide. "All you ever heard about, all you ever
read about, was one pitch."

Reminders of unpleasant experiences can also induce us to engage in
what psychologists call "counterfactual thinking" - generating alternative
scenarios of what might have been or should have been. Anyone who has
invested in the stock market is likely familiar with the power of counterfactual thinking. You track a favorite stock as its price steadily rises. Finally,
you work up the nerve to invest, and in no time your worst fears are realized - the market begins a correction and you lose 20 percent from your
investment within a few days. As you helplessly watch the stock drop, you
become overwhelmed with regret over your hasty action. If only I had been
more patient and waited for the market to tumble, you chide yourself as
you relive the moments leading up to your decision to throw money after
the stock. You wake up at night ruminating about your decision, imagining
how happy you would have been had you decided to wait just one or two
more days to invest. Such counterfactual thinking can easily lead to the
kind of hindsight biases we considered in Chapter 6.

I experienced an unsettling episode of such counterfactual thinking
during a recent trip to a midwinter conference in Florida. Scheduled to return to Boston on a Friday night, I heard a weather report warn of a massive storm that would surely result in my flight's cancellation. Should I
leave the conference early and try to beat the storm to Boston, or relax and
enjoy another day or two of Florida sunshine? After some hesitation I
opted to out race the storm. The strategy almost worked: my flight was
cleared to land in Boston, and it looked as if I would arrive home ahead of
the blizzard. But conditions deteriorated rapidly, the pilot was unable to
touch down, and we ended up making an emergency landing in Maine.
Then I endured an eighteen-hour odyssey of waiting, another failed landing attempt, a diversion to Kennedy Airport in New York, and finally an
overnight limousine ride to Boston with several other flustered passengers.
Why didn't I stay in the sunshine, I kept thinking to myself as the situation
fell apart. Reflecting back on the moment when I decided to try to outrace
the storm, I imagined myself on the phone to the airline, making the now
clearly wise decision to remain in Florida a little while longer.

Persistent counterfactual thinking can be far more serious when people feel that they could have or should have acted to prevent a tragedy.
Friends and relatives of people who commit suicide, for instance, are frequently plagued by persisting counterfactual thoughts about what they
could have done or should have done to prevent a loved one from taking
his life. "Some survivors will blame themselves for not intervening:' concludes the British suicide expert Mark Williams, "and endlessly ruminate
on what they could have done to prevent it." Even after a loved one died
from an un treatable illness, grieving family members "found themselves
repeatedly reviewing, going over in their minds, the events leading up to
the death, often endlessly replaying the incident, as if by doing so they
could undo or alter the events that had occurred." One widow paralyzed
by persistent counterfactual thinking commented, "I go through that last
week in the hospital again and again. It seems photographed on my mind."
Consistent with these real-life examples, laboratory studies have revealed
that negative experiences result in higher levels of subsequent counterfactual, "if only" kinds of thinking than do positive experiences.

Persisting memories and counterfactual thinking almost invariably
accompany such overwhelming events as the death of a loved one. But responses to many kinds of disappointments and failures depend, at least in
part, on previous experiences that shape the way we view ourselves: even
relentless reminding of an unpleasant experience need not result in paralyzing counterfactual thinking or the kind of crippling persistence that undermined Donnie Moore. Consider the case ofJean Van de Velde. This previously unknown French golf professional captured international attention
in July 1999 when he led the prestigious British Open in the tournament's
final round. Standing on the eighteenth tee, Van de Velde held a commanding three-shot lead and seemed assured of victory, needing only to avoid a
complete disaster to win. Instead, he collapsed: wild shots into the remote
reaches of rough and water led to a triple-bogey eight as millions of golf
fans around the world watched incredulously. Van de Velde fell into a
three-way tie for the lead, and then lost the tournament in a playoff, completing the most stunning meltdown that professional golf had ever witnessed.

Recognizing the magnitude of the disaster, articles the next day in
London newspapers proclaimed that the bitter memory of his collapse
would torment Van de Velde for the rest of his life. But that's not what happened. Though shaken and disappointed in the hours and days after he lost
the tournament, Van de Velde did not become a prisoner of persisting
memory the way that Donnie Moore did. Nor did he endlessly engage in
counterfactual thinking about what he could have done or should have
done on the fateful eighteenth hole. Instead, he explained the rationale for
some of the controversial decisions he had made - decisions that backfired - and placed the experience in a broader perspective, noting that
golf is a game and only one part of his life. Van de Velde also enjoyed the
new fame he had achieved by contending in an event of international stature. "Maybe it's in my temperament," Van de Velde commented several
weeks later when reporters asked how he managed to handle the situation
so well and avoid endlessly reliving what had happened on the final hole. "I
don't live in the past."

The contrasting fates of Donnie Moore and Jean Van de Velde remind
us that long-lasting persistence is not an inevitable consequence of all
disappointments: how we respond to adversity, and whether we become
plagued by persistence, depends on how we evaluate and appraise what
happens to us. Psychologists refer to the compilations of past experiences
that influence current evaluations as "self-schemas:' Built up over years
and decades, self-schemas contain evaluative knowledge of our own characteristics. Consider whether the following words describe you: sad, optimistic, successful, or lethargic. To make such judgments, you consult a selfschema that contains relevant information based on individual experiences
and composite pictures from different stages of your life. Emotionally
healthy people tend to endorse more positive than negative words, whereas
depressed individuals endorse more negative than positive words. Depression is associated with a highly negative self-schema, resulting in a chronic
perception of oneself as an inadequate or flawed individual.

The great Russian poet Alexander Pushkin captured some of the searing emotions associated with intrusive memories that reinforce a negative
life script or self-schema:

And in the idle darkness comes the bite.
Of all the burning serpents of remorse;
Dreams seethe; and fretful infelicities.
Are swarming in my over-burdened soul.
And Memory before my wakeful eyes.
With noiseless hand unwinds her lengthy scroll.
Then, as with loathing I peruse the years.
I tremble, and I curse my natal day.
Wail bitterly, and bitterly shed tears.
But cannot wash the woeful script away.

A negative self-schema can easily lead to depression because it provides a rich network of knowledge that facilitates encoding and later retention of negative experiences. When depressed patients make judgments
about whether such words as failure or happy describe them accurately,
they later recall more of the negative words, but not more positive words,
than healthy controls. The Harvard psychologist Patricia Deldin has found
that depressed and nondepressed individuals show different patterns of
electrical brain activity during encoding of positive and negative information. Depressed patients, relative to healthy controls, showed larger electrical responses to negative than positive words. These differences, which occur during the fleeting moments when a new memory is born, create
conditions that favor persistent retrieval of negative experiences - which
in turn can heighten depressed mood, contributing to a self-perpetuating
and potentially vicious cycle.

We don't know whether Donnie Moore possessed an unusually negative self-schema that left him vulnerable to persistence, nor do we know
whether Jean Van de Velde possessed an exceptionally positive self-schema
that protected him from memory's seventh sin. But we do know that patients suffering from clinical depression are especially prone to persistence.
Studies carried out by the University of London psychologist Chris Brewin
and his associates reveal that depressed patients are much more prone to
intrusive memories of negative experiences than are healthy controls. In
one study, for instance, Brewin's group found that nearly all patients who
became depressed as a result of a recent death, health problem, or an incident of abuse or assault reported persistent and unwanted memories related to the precipitating event.

Brewin also examined intrusive memories in people who had recently
received a cancer diagnosis. Some of these individuals sunk into a severe
depression, others became mildly depressed, and still others did not develop depression. The severely depressed patients reported many more intrusive memories - mainly related to illness, injury, and death - than did
either the mildly depressed or non depressed patients. This intensified persistence could be attributable to the negative mood that prevails in a severe
depression. Laboratory studies have shown that current mood state influences the kinds of memories that people tend to retrieve: in happy moods,
recollections of positive experiences spring to mind more readily than recollections of negative experiences; the opposite tends to occur in dark
moods. The cancer patients' intrusive memories could also be related to
negative self-schemas that predispose patients to developing depression in
the first place: these patients may have a larger store of negative memories
than patients who prove emotionally resilient in the face of a cancer diagnosis. Once again, conditions are in place for a self-perpetuating cycle in
which negative self-schemas and moods create fertile ground for persistent
retrieval of negative memories, which in turn amplifies the severity of depression.

The University of Michigan psychologist Susan Nolen-Hoeksema and her collaborators have found that people with a "ruminative" style, who focus obsessively on their current negative moods and past negative events,
are at special risk for becoming trapped in such destructive self-perpetuating cycles. Those with a ruminative style endure longer episodes of depression than individuals who do little ruminating. For instance, prior to the
1989 Loma Prieta earthquake that shook the northern California Bay Area,
Nolen-Hoeksema measured mood and tendencies toward rumination in a
large group of college students. In the days and weeks following the destructive event, she assessed their moods and emotional responses. Students who exhibited a ruminative style before the earthquake were more
likely to be depressed weeks afterward than students who had not shown
signs of a ruminative style prior to the quake. More rumination after the
earthquake was linked with longer and more severe depression. NolenHoeksema observed something similar in caregivers of terminally ill patients, who are at great risk for depression. Caregivers who tended to ruminate on present and past negative events became more severely depressed
during the course of a terminal illness than those who did not.

Nolen-Hoeksema's group has recently linked rumination, depression,
and memory even more strongly. College students who were experiencing
depressed or nondepressed moods engaged in two types of tasks. The rumination task focused on students' current mood, energy level, and past
events that influenced them to turn out the way that they did. The distracting task drew attention away from the students' moods and concerns, requiring them to imagine the Mona Lisa's face or douds forming in the sky.
Students were then asked to recall autobiographical incidents from their
pasts. For students who were already experiencing a depressed mood, engaging in the rumination task led to recall of more negative autobiographical memories than did the distracting task.

Ruminative tendencies may explain some differences between the responses of men and women to depression. Nolen-Hoeksema monitored
episodes of depression in women and men for a month. She found that
women were more likely than men to ruminate over their depressed
moods; men were more likely to engage in distracting activities that drew
attention away from their negative moods, such as spending more time on
work or hobbies. High levels of rumination contributed to longer-lasting
and more severe depressive episodes in women than in men. Here again,
the vicious cycle of rumination, memory, and depression was at work.

Women ruminated by asking questions about why they were depressed,
thereby activating a wealth of negative memories: past experiences in
which they felt inadequate or otherwise saw themselves in a negative light.
These negative memories further deepened an already black mood, leading
to more prolonged and painful depression. By fleeing into distracting activities, men escaped this downward spiral.

It's important to distinguish between ruminating about a painful experience and disclosing it to others. Rumination involves a kind of obsessive recycling of thoughts and memories regarding one's current mood or
situation which produces an even worse outcome. Disclosing difficult experiences to others, however, can have profoundly positive effects. The psychologist James Pennebaker and coworkers at the University of Texas have
carried out studies in which people disclose troubling experiences by writing or talking about them for several days. The resulting narratives that
people create produce surprising benefits: more positive mood, enhanced
immune system functions, fewer visits to the doctor, higher grade point
averages, reduced absenteeism at work, and even higher rates of reemployment following job loss. Although the exact reasons for these benefits are
still a matter of debate, the findings suggest that the act of converting turbulent emotions into narrative form influences important physiological
systems.

The difference between generating useful narratives and endlessly ruminating is apparent in very severe or suicidal depression. Patients suffering from suicidal depression may have difficulty coming up with coherent
narratives because they persistently recall and ruminate over what the British psychologist Mark Williams calls "overgeneral memories." Several years
ago, Williams began conducting experiments on autobiographical memory
in suicidally depressed patients using a widely adopted word-cueing technique. Try to recall a specific incident from your life for each of the following words: happy, sorry, angry, and successful. Most people have no difficulty coming up with detailed recollections of particular experiences. In
response to happy, for instance, I recalled how pleased I felt when I watched
my daughter Hannah score six points during a recent game in her fourthgrade basketball league. For sorry, I remembered how bad a professional acquaintance felt when she lost a set of slides I used to deliver a lecture at her
university.

Williams noticed that severely depressed patients rarely generated
memories of specific incidents in response to either positive or negative
cues - even though, as we saw earlier, Kevin Ochsner's results suggest that
the natural tendency is to remember negative events in great detail. Instead,
they came up with summary descriptions, such as "when I do things
wrong" in response to the cue sorry, or "my father" in response to happy.
Williams notes that persistent retrieval of overgeneral memories can contribute to an eventual decision to commit suicide. An unpleasant event that
turns out to be the final straw in a suicidal decline can stimulate recall and
rumination about negative overgeneral memories, such as "I've always
been a failure" or "Nobody's ever really liked me." A patient may be overwhelmed by persistent recall of such self-damaging descriptions, which
dominate the patient's mind and lead to a decision to take his own life.

Studies of brain activity in depressed patients provide some clues concerning possible underlying bases of persistent overgeneral memories. Several studies have found that depressed patients show relatively reduced activity in parts of the left frontal lobe, mainly on the lateral surface (the
dorsolateral frontal region), either when they are resting comfortably or
performing cognitive tasks. Patients who suffer strokes to the left frontal
lobe often become depressed, whereas patients with right frontal damage
typically do not become depressed. The affected regions in the left frontal
lobe may playa role in the generation of positive emotions.

From the standpoint of memory, neuroimaging studies suggest that
similar regions in the left prefrontal cortex playa role in reflecting back on
past experiences and retrieving specific aspects of what happened. In studies conducted by the Yale University psychologist Marcia Johnson and her
group, the amount of activity in the left prefrontal cortex during retrieval
was greatest when people recalled particular details of past episodes. If severely depressed patients have more trouble activating key regions of the
left frontal lobe, they may be particularly vulnerable to persistent recall of
overgeneral memories. A healthy individual might be able to counter retrieval of negative memories by recalling a specific positive experience. If,
having had a paper rejected from a scientific journal, I am reminded of
previous rejections and conclude that I am a lousy researcher, I still can
generate specific memories of papers that journal reviewers accepted enthusiastically. Supported by these positive memories, I begin to feel better
about my abilities and resolve to revise the rejected paper for publication
elsewhere. But if I am depressed and thus unable to generate specific recollections, I could well become overwhelmed by intrusive overgeneral memories that match my despairing mood - "I've always had problems publishing in the top journals;' "I feel like a failure again" - further increasing
my sense of despair. A dysfunctional left frontal lobe might well contribute
to this destructive cycle.

Persistence, then, thrives in an emotional climate of disappointment,
sadness, and regret. But to witness the full force of the seventh sin, we need
to turn our attention to the world of traumatic experiences.

TERROR IN THE PAST.

In Sacai ... the ... earthquake was so terrible unto them, that many
were bereft of their senses; and others by that horrible spectacle so
much amazed, that they knew not what they did. Blasius, a Christian
the reporter of the newes, was so affrighted for his part, that though it
were two months after, hee was scarce his owne man, neither could hee
drive the remembrance of it out of his min de. Many times, Some years
following, they will tremble afresh at the remembrance or conceipt of
such a terrible object, even all their lives long, if mention be made of it.
In his classic seventeenth-century treatise, The Anatomy of Melancholy, the
British writer Robert Burton described the devastating psychological consequences of an ancient earthquake. The experience of Blasius and others
in Sacai has been replicated countless times across centuries and millennia: traumatic experiences almost invariably result in intrusive, persisting
memories of a terrible event.

In the twentieth century, the damaging effects of traumatic experiences on memory and other mental functions were first recognized during
World War 1. Doctors began treating cases of "shell shock;' in which soldiers exposed to life-threatening situations later become incapacitated by
recurring nightmares and intrusive memories of their encounters with
death. After the war, the British government established a committee to determine whether soldiers who had been executed for cowardice had in fact
been suffering from shell shock. World War II produced another upsurge
in cases of shell shock, but what we now call post-traumatic stress disorder
became widely acknowledged and formally recognized by medical practitioners only after the conclusion of the Vietnam War. Hospitals and other
organizations charged with caring for returning veterans became inundated with cases in which intrusive war memories and recurrent batde
nightmares interfered with the ability of affected veterans to resume their
lives at home and to reintegrate with society.

Persisting memories are a major consequence of just about any type
of traumatic experience: war, violent assaults or rapes, sexual abuse, earthquakes and other natural disasters, torture and brutal imprisonment, motor vehicle accidents. Though such events may seem like relatively rare occurrences, epidemiological studies suggest that just over half of women and
60 percent of men will experience at least one traumatic event in their lives.
The intrusive memories that result from such experiences usually take the
form of vivid perceptual images, sometimes preserving in minute detail
the very features of a trauma which survivors would most like to forget.
Though intrusive recollections can occur in any of the senses, visual memories are by far the most common. The Oxford psychologist Anke Ehlers
studied the perceptual qualities of intrusive memories in people who had
been traumatized by sexual abuse or road traffic accidents. For both types
of trauma, visual recollections predominated in nearly all survivors, with
some remembering "single pictures" of the traumatic incident and a similar proportion recalling multi-image "film clips." Other senses still played
some role: more than half of both sexual abuse and traffic accident survivors reported experiencing intrusive memories in the form of smells,
sounds, or bodily sensation.

Post-traumatic stress disorder, or PTSD, is often associated with depression. Chris Brewin has direcdy compared intrusive memories in traumatized patients and in depressed patients who had not experienced a
specific trauma. Patients with PTSD reported more frequent intrusive
memories and flashbacks than did depressed patients, but the qualities of
the memories were generally similar in the two groups. Traumatized patients, however, reported more unusual dissociative experiences, in which
they felt as though they were observers watching an event happen to someone else.

Studies of trauma survivors indicate that nearly all of them experience
troubling intrusive memories in the days and weeks after a trauma occurs.
But, just as we saw with Jean Van de Velde, not everyone continues to be
plagued by intrusive recollections months, years, or decades later. Those
who continue to experience intrusive memories long after a traumatic
event, and who as a result cannot return to normal functioning in their
everyday lives, are likely to receive a diagnosis of post-traumatic stress disorder.

For some people, the force of a traumatic event is so compelling that
they become "stuck" in the past. Studies of Vietnam veterans and victims
of sexual abuse indicate that individuals who remain focused on the past
for years after a traumatic event exhibit higher levels of psychological distress than those who focus on the present and future. High levels of psychological distress in turn stimulate even greater focus on the past, thus
setting up a destructive self-perpetuating cycle of persistent remembering
like that observed in cases of depression.

The likelihood of getting stuck in the past depends in part on how a
person responds in the immediate aftermath of a trauma. Recall the terrible 1993 firestorms in southern California which destroyed vast swathes of
property, threatened lives, and forced scores of people to abandon their
homes. Alison Holman and Roxane Silver of the University of California at
Irvine interviewed survivors of the firestorms in nearby Laguna Beach and
the Malibu-Topanga area of Los Angeles within a few days of the disaster,
and then followed up six: months and one year later. Immediately after the
fires, some survivors reported disturbances in their sense of orientation in
time: they felt that time had stopped or that the present was no longer continuous with the past or the future. People who experienced high levels of
such "temporal disintegration" immediately after the firestorms were especially likely to focus on and ruminate about the event six: months later. A
year after the firestorms, these same individuals experienced more distress
than did people who were able to focus more on the present or future in the
intervening months. Temporal disintegration in response to a trauma thus
foreshadowed later troubles in people who remained stuck in the past, prisoners of persistent memories.

Long-term psychological trouble can also result from attempting to
avoid thinking about a traumatic event in its immediate aftermath. The
overwhelming pain of a traumatic experience and associated intrusive
memories naturally leads people to want to avoid reminders of the incident
and, if possible, to suppress trauma-related memories and thoughts. Consider the protagonist in Sarah Van Arsdale's 1995 novel Toward Amnesia.
Libby has recently been abandoned by her lover and is trying to deal with
persisting memories of their relationship. She devises a plan of psychological escape from memories that burden her continually. "It was on Memorial Day I decided to achieve amnesia:' the novel begins. First trying to
attain this goal by simply admonishing herself to forget - 'Td gotten
through ... by chanting that mantra or the other one: forget, forget, forget" - Libby eventually flees the ever-present reminders of her relationship, driving hundreds of miles to Canada in order to seek refuge from
memory.

Though the prospect of forgetting may seem soothing after a disappointment or trauma, such attempts are likely to backfire. Consider a
group that is at high risk for intrusive traumatic memories: emergency
service personnel. Ambulance crews, firefighters, and disaster relief workers are frequently exposed to upsetting, sometimes overwhelming, events.
In a study of ambulance workers, Anke Ehlers and her collaborators found
that virtually all of them experienced some work-related intrusive memories. The most common sources of intrusive memories were accidents involving the loss of children or acquaintances, violent deaths, severe burns,
or failed attempts to save a life. But despite the ubiquity of persisting traumatic memories in ambulance workers, just one in five of Ehlers's sample
met the criteria for PTSD. These individuals often responded initially by
trying to avoid remembering the trauma. They tended to interpret their
traumatic recollections as an indication that they were going mad or otherwise unraveling. Instead of working through the traumatic event initially,
they retreated into wishful thinking, sometimes trying to alter or undo the
past in fantasies. Yet attempts to avoid distressing memories resulted in
only more rumination and distress with the passing of time.

These observations fit nicely with pioneering laboratory studies conducted by the Harvard psychologist Daniel Wegner concerning paradoxical
or ironic effects of attempting to suppress unwanted thoughts. In Wegner's
experiments, people are instructed to try to avoid thinking about a particular topic - a neutral concept such as a white bear, or a personally meaningful one like an old flame. Wegner finds that following a period of
thought suppression, participants in his experiments usually show a "rebound effect": they later think about the forbidden subject more often and
intensely than they would have if they had never attempted to suppress
thinking about it in the first place. "Although not thinking about painful
thoughts may seem like a reasonable coping strategy to adopt:' comments
Wegner, "trying to forget might not only prolong the misery, but make it
worse." Wegner's ideas are backed up by other studies showing that after
exposure to distressing films, people who are instructed to suppress
thoughts related to the film later experience more film-related intrusive
memories than those who do not try to suppress. Attempts to avoid thinking about a horrendous experience are common in trauma survivors, but
are more likely to amplify, rather than lessen, later problems with persisting
memories.

One possible reason for this phenomenon is that reexperiencing a
traumatic event in an otherwise safe context can take out some of the sting.
Repetition of just about any stimulus or experience will result in what researchers call habituation - a reduced physiological response to the stimulus. If I playa loud sound for you at regular intervals and record physiological activity, at first you will show a strong response to the sound,
followed by a gradual drop-off. The same goes for traumatic memories: repeated reexperiencing of a traumatic memory in a safe setting can dampen
the initial physiological response to the trauma. Attempts to suppress
memories of upsetting experiences prevent this normal process of habituation. Suppressed recollections thus retain an extra charge that eventually
augments persistence.

Perhaps not surprisingly, then, therapeutic attempts to counter persistence in trauma survivors almost invariably focus on allowing patients to
reexperience the traumatic event within the safe confines of the therapy
setting. The approaches that have proven most effective are imaginal exposure therapies: patients are repeatedly exposed to stimuli associated with
their traumas and they recall and reexperience vivid images of the incidents. In the early 1980s, the Boston psychologist Terrence Keane and his
associates reported that exposure therapy reduced levels of anxiety and intrusive memories in Vietnam veterans, and others reported similar effects
in survivors of sexual abuse. Later studies directly compared imaginal exposure therapy to other kinds of treatments that do not involve repeated
reexperiencing of trauma, such as supportive counseling. Keane's group
and another team led by the psychologist Edna Foa found that exposure
therapy produced the greatest reductions in intrusive memories, flashbacks, and related symptoms of PTSD.

The psychiatrist Stevan Weine and his collaborators have recently described a related approach to reducing persistence in people who have been
traumatized by state-sponsored terrorism. Refugees who escaped the attempted genocide several years ago in Bosnia-Herzegovina often showed
classic symptoms of PTSD, including overwhelming intrusive memories.
Weine and his collaborators are exploring the effectiveness of what they call
"testimony therapy:' in which survivors retell and relive their traumatic experiences, and try to relate them to the traumas suffered by others in their
society. Weine's group gathered survivors' recollections into an oral history
archive that was shared with other patients as part of the testimony therapy
process. "Within this context, where the survivors explicitly understand
that their remembrances are becoming part of a collective inquiry:' observed Weine, "testimony can reduce individual suffering, even when survivors have not explicitly sought trauma treatment." Preliminary results indicate that testimony therapy does indeed produce reduced levels of intrusive
memories in traumatized Bosnian refugees.

These findings fit well with James Pennebaker's studies concerning the
beneficial effects of disclosing disappointments, losses, and other negative
experiences. In the short term, persistence is a virtually inevitable consequence of difficult experiences. But for the long term, confronting, disclosing, and integrating those experiences we would most like to forget is the
most effective counter to persistence.

THE ROOTS OF PERSISTENCE.

To understand better why traumatic events produce such powerful persistence in the first place, it's helpful to consider the neural systems involved
in remembering trauma. A key player in the brain's response to traumatic
events is a small almond-shaped structure called the amygdala. Buried
deep in the inner regio~s of the temporal lobe, the amygdala abuts the
nearby hippocampus, but performs quite different functions than does its
neighbor. Recall that when people sustain damage to the hippocampus and
surrounding cortical areas, they almost invariably suffer a general impairment in forming and later retrieving new episodic memories of personal
experiences. Damage to the amygdala does not result in this sort of global
memory deficit: patients with amygdala damage can remember their recent
experiences with little difficulty. The memories of patients with amygdala
damage, however, do not benefit from the emotions that normally accompany an arousing experience and aid subsequent recollection. Consider
what happens when healthy people view a slide sequence that begins mundanely - a mother walking her child to school - and later includes an
emotionally arousing event: the child is hit by a car. When tested later,
healthy people remember the arousing event better than the mundane
ones. Patients with amygdala damage remember the mundane events normally, but do not show improved memory for the emotionally arousing
event.

Abnormal fear responses are a hallmark of amygdala damage: patients
have great difficulty learning to fear situations that would normally scare
the rest of us. Consider a rape victim who begins to experience fear and
distress every time she drives near the park where she was assaulted. There
is nothing inherently frightening about this particular park, but for the
rape survivor it has become inextricably associated with trauma. Researchers have created experimental analogues of fear learning by using conditioning procedures that expose people or animals to normally innocuous
stimuli that are associated with a fear-inducing event. The procedures are
based on the famous conditioning experiments conducted in the early
1900S by the Russian physiologist Ivan Pavlov. Pavlov's dogs learned to salivate at the sound of a bell because it was previously associated with the enjoyable experience of gnawing on a piece of meat. Something similar happens with fear. Imagine that I show you a series of colored slides, and that
every time you see a blue slide you also hear the jolting sound of a loud
horn. It won't be too long before the appearance of a blue slide will induce
an emotional response, as you begin to dread the occurrence of the obnoxious sound. Researchers can measure this reaction by monitoring skin conductance responses, which provide a rough-and-ready index of emotional
arousal.

When patients with amygdala damage participated in this kind of
conditioning procedure, they did not show any signs of fear or emotional
arousal with repeated presentations of the blue slides. The psychologist
Elizabeth Phelps videotaped one such patient who had just participated in
a similar conditioning procedure. The patient knew perfectly well that
whenever the blue slide appeared, a loud unpleasant sound would begin to
blare. "Blue slide, loud sound;' she confidently announced to Dr. Phelps.
Nonetheless, the patient showed no signs of fear learning - physiological
arousal in response to the blue slide - at any time during the conditioning
experiment.

These findings fit neatly with numerous studies in rats and other experimental animals showing that damage to the amygdala disrupts fear
conditioning. When a normal rat receives an electric shock after hearing a
particular tone, it will soon behave fearfully upon hearing the tone alone.
The neuroscientist Joseph LeDoux, who has performed pioneering studies
on fear conditioning, provides a vivid description of a terrified rat:

After very few such pairings of the sound and the shock, the rat begins to act afraid when it hears the sound: it stops dead in its tracks
and adopts the characteristic freezing posture - crouching down and
remaining motionless, except for the rhythmic chest movements required for breathing. In addition, the rat's fur stands on end, its blood
pressure and heart rate rise, and stress hormones are released into its
bloodstream. These and other conditioned responses are expressed in
essentially the same way in every rat.

leDoux and others have discovered that selectively damaging specific
regions within the amygdala eliminates these telltale signs of fear. leDoux's
group has further shown that memories created during fear conditioning in healthy animals are exceptionally durable - perhaps even indelible.
Combined with the work on brain-damaged patients, these observations
suggest that the amygdala plays a role in generating the kinds of persisting
memories that haunt survivors of traumatic events.

As leDoux points out, the amygdala is well positioned to guide evaluation of the personal significance of incoming information - the essence
of emotional responding. He likens the amygdala to the hub of a wheel: it
receives raw sensory information from the thalamus, a key subcortical
switching station; more extensively processed perceptual information from
higher-order areas in the cortex; and signals from the hippocampus about
the general context of an event. Alerted by this converging information, the
amygdala can flag the occurrence of a significant event.

The amygdala also has a powerful influence on hormonal systems that
kick into high gear when we are confronted with a frightening or otherwise
arousing event. The release of stress-related hormones, such as adrenaline
and cortisol, mobilizes the brain and the body in the face of threat or other
sources of stress, and also enhances memory for the experience (probably
by influencing the activity of the hippocampus). When the amygdala is
damaged, however, stress-related hormones no longer produce any memory enhancement. The amygdala thus regulates or modulates memory
storage by turning on the hormones that allow us to respond to and remember vividly - but sometimes intrusively - threatening or traumatic
events.

Neuroimaging techniques are beginning to provide new insights into
the role of the amygdala and other brain structures in persistent memories
of traumatic events. Several studies using PET and fMRl have shown that
the amygdala is strongly activated by the presentation of aversive materials:
pictures of mutilated bodies, film clips of traumatic events, even faces with
angry or fearful expressions. These neuroimaging studies are particularly
intriguing, because seeing a face with a fearful expression does not necessarily elicit an emotional response from the viewer. Experiments by the
University of Wisconsin neuroscientist Paul Whalen and his coUaborators
reveal that even when fearful faces are presented so briefly that people do
not consciously discern the expression - participants report that they see
"expressionless" faces - the amygdala still shows greater activity for fearful faces than for happy faces. These and related results led Whalen to propose that the amygdala is turned on by events that signal a possible threat
in the environment.

When the amygdala lights up during threatening or aversive events,
the amount of activity predicts how well people later remember these experiences. Larry Cahill and James McGaugh at the University of California at
Irvine performed PET scans while people viewed film clips containing both
neutral and upsetting episodes. Later, participants tried to recall episodes
from the film. The amount of activity in the amygdala was closely correlated with the number of upsetting episodes that people recalled: the more
amygdala activity during film clip viewing, the more aversive incidents
later recalled. They found no such relationship for neutral incidents (interestingly, the amount of activity in the hippocampus correlated with subsequent recall of neutral, but not aversive, incidents).

Neuroimaging studies have also shown that, consistent with studies of
rats and other animals, the amygdala is strongly activated during fear conditioning. It is perhaps not surprising, then, that several imaging studies of
trauma survivors, including Vietnam War veterans and victims of sexual
abuse, have also documented amygdala activation when survivors recalled
and relived traumatic events that they remember intrusively in their everyday lives. Imaging studies also reveal heightened activity during traumatic
recollections in several other brain regions thought to playa role in fear
and anxiety - one tucked deep down in the frontal lobe, another near the
tip of the temporal lobe. These findings can help to explain why persistent
recollections of trauma often preserve the intense fear and anxiety that prevailed during the original experience.

Consistent with animal studies implicating stress-related hormones in
fear conditioning, studies of trauma survivors have also related these hormones to intrusive recollections. When stress-related hormones spring into
action during an emotionally arousing experience, they stimulate the release of a class of chemical messengers known as catecholamines. Researchers have focused in particular on the role of norepinepherine, one of
the major catecholamines. Several studies of Vietnam veterans and victims
of sexual abuse have found that greater levels of norepinepherine (measured in urine samples) are associated with more frequent intrusive memories of traumatic experiences. Further, when traumatized patients were administered the drug yohimbine, which raises levels of norepinepherine in
specific brain regions, nearly half of the patients experienced overwhelming visual flashbacks of a traumatic event, often accompanied by fear and
even panic.

Yohimbine is available over the counter in pharmacies and health
food stores, where it is marketed as an aphrodisiac, a remedy for male impotence, and a general energy booster. Several PTSD patients who purchased the drug experienced unexpected flashbacks and panic attacks. "I
felt like I was going crazy;' reflected one veteran who took yohimbine as an
aphrodisiac and instead found himself overwhelmed by unwanted war
flashbacks. "I kept thinking that my combat buddy was wounded. I kept
thinking that I was a medic and that I had to save him."

Though its effects are most dramatic in patients suffering from PTSD,
other studies have shown that giving normal volunteers yohimbine while
they view emotionally arousing slides enhances later recall of the emotional
events, probably by increasing levels of norepinepherine during encoding.
Norepinepherine supplies a chemical spark that ignites intrusive recollections.

Understanding the chemical and hormonal bases of persistence also
provides clues about how to counter it pharmacologically. If yohimbine or
other substances that boost stress-related hormones and norepinepherine
also heighten persistence, then it stands to reason that substances that
lower stress-related hormones and norepinepherine should reduce persistence. This result is exactly what Larry Cahill and James McGaugh found in
a study in which they administered a drug - the beta-blocker propranolol
- that prevents the release of stress-related hormones. Some participants
watched a slide show depicting mundane events, whereas others watched a slide show in which an emotionally arousing event was interposed among
the mundane ones. The group that received propranolol remembered the
mundane events about as well as a group that received an inactive placebo
pilL But an important difference also emerged: memory for the arousing events improved substantially in the placebo group, but not in the
propranolol group. Propranolol effectively blocked the usual memoryenhancing effects of emotional arousal.

These results raise the intriguing possibility that beta-blockers such as
propranolol could be administered to trauma survivors in order to reduce
persisting memories. Beta-blockers might also be given ahead of time to
emergency workers before they enter a disaster site, and thus thwart altogether the development of intrusive memories that will plague them later.
These are exciting possibilities because intrusive memories can be so crippling for long periods of time. And for emergency or disaster personnel
who are repeatedly exposed to potential sources of persistence, preliminary
administration of beta-blockers might make a highly stressful occupation
more manageable.

But this strategy for countering persistence also poses risks. We've
seen that attempts to avoid traumatic memories often backfire. Intrusive
memories need to be acknowledged, confronted, and worked through in
order to set them to rest for the long term. Unwelcome memories of
trauma are symptoms of a disrupted psyche that requires attention before
it can resume healthy functioning. Beta-blockers might make it easier for
trauma survivors to face and incorporate traumatic recollections, and in
that sense could facilitate long-term adaptation. Yet it is also possible that
beta-blockers would work against the normal process of recovery: traumatic memories would not spring to mind with the kind of psychological
force that demands attention and perhaps intervention. Prescription of
beta-blockers could bring about an effective trade-off between short-term
reductions in the sting of traumatic memories and long-term increases in
persistence or related symptoms of a trauma that has not been adequately
confronted.

For all its disruptive power, persistence serves a healthy function:
events that we need to confront come to mind with a force that is hard to
ignore. The seventh sin - just like the other six - is not merely an inconvenience or annoyance, but is instead a symptom of some of the greatest
strengths of the human mind.