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Re: Science and moral politics
The intriguing New Yorker article Eugene shared, on the complex issue of
studying how and how much we recover from traumatic and troubling
experiences, reminded me of the flip side, also controversial: studying
how we develop recovered memories, including post-traumatic stress, from
imagined and suggested experiences, discussed in this article in a recent
issue of Discover.
- Steve
Are Recovered Memories Real?
A growing body of evidence indicates that memory is deeply unreliable and
that life-shattering events cannot be buried for years and then winched
out of the deep waters of the subconscious
By Jill Neimark
DISCOVER Vol. 25 No. 08 | August 2004 | Mind & Brain
You are lying naked on a metal table, your legs strapped into restraints.
You can see luminescent alien beings with big, froglike eyes as they move
about in the darkness. They begin to cut into your body, and you are
afraid they might cut out your heart. . . .
That description comes from a study of people who claim to be alien
abductees, which was conducted at Harvard University and published in the
journal Psychological Science this summer. The transcript was distilled
from a recorded interview with an ?abductee? and was then played back to
him while researchers measured signs of post-traumatic stress disorder.
Listening to his own story triggered physiological responses as
pronounced as those seen in combat veterans. Similar physiological
responses were measured in nine other abductees in the study.
The halls of Harvard, nestled amid the 19th-century clapboard houses and
cobbled streets of Cambridge, seem an unlikely place to take
extraterrestrials seriously. But the study is part of a six-year probe by
Harvard psychologist Richard McNally and his colleagues into the minds of
apparently sane people who believe they have memories of long-repressed
events, including sexual abuse, alien abduction, and past lives. The
study is an attempt to learn if humans can create memories unwittingly,
memories so strong they may cause the debilitating symptoms of
post-traumatic stress disorder.
McNally thinks people can and do make up powerful memories. And
these false memories can take on a life of their own, with profound
legal, political, and social consequences. If juries find plaintiffs?
recovered memories credible, people go to jail. About a decade ago, a
wave of cases involving recovered memories of sexual abuse tore families
apart, led to lurid court trials, and spawned a branch of therapy devoted
to recovered memories. Today another wave of trials are under way
involving allegations of sexual abuse of children by priests. More than
500 cases of sexual abuse are pending in the Boston archdiocese alone.
McNally says many of these cases involve ?supposedly recovered
memory.?
His research suggests that all memorieseven false onesare not just
accessories of experience. Memory is experience, McNally says, a
neurohormonal event that cascades through the brain and, when accompanied
by powerful emotions, is burned into synapses. And he wonders how and why
the human brain does this.
There are no definitive answers yet, but there are powerful clues. With
the help of sophisticated neuroimaging techniques, researchers are
finding that memory?s malleability is yoked to some of our most cherished
aspects of intelligence: imagination, inference, and prediction. These
are the same capacities that make us Earth?s dominant species. And
because of this, it?s likely that memory?s vulnerability to error is here
to stay.
At the turn of the last century, Freud invoked the concept of repression,
a protective mental mode that smothers distressing emotional events.
Scientists have been sparring over the nature of memory ever since, and
in the last few decades the fight has become so acrimonious that
psychologist Kathy Pezdek, of Claremont Graduate University in
California, likens it to a religious war. Elizabeth Loftus, a
psychologist at the University of California at Irvine, whose studies of
false memory have made her the target of a lawsuit and a separate
investigation by her former university, says her ?life has been derailed?
by her research. McNally echoes her: ?I?ve had to consult Harvard?s
general counsel on three different occasions because of the saber
rattling of trauma experts who didn?t like my work.? Susan Clancy, a
psychologist who trained under McNally, says: ?When I started this
research, hate mail poured in by the ton. One colleague told me to get
out of the area entirely since I?d be ruling myself out of job
opportunities.?
Researchers are at war because there is no definitive evidence that
life-shattering events can actually be buried for years, as Freud
suggested, then winched out of the deep waters of the subconscious like a
long-lost corpse. Yet people who claim to have done exactly that are
tremendously convincing. Their sensory details are often striking and
terrifying in their clarity. And these memories are intense enough to
forever alter lives. ?This experience [of abduction] really hits you in
the pants,? says Will Beuche, an abductee who participated in McNally?s
study. ?All your assumptions about life are broken. It feels like
everything you had based your character development on was wrong. You
feel washed up on the shore with no personality at all.?
Such certainty is strong enough to convince another Harvard psychiatrist
that the experiences, if not the abductions themselves, are real. John
Mack, who heads the John E. Mack Institute a few minutes? walk from
McNally?s office, speaks of the ?ontological shock? he went through when
he first listened to the stories of abductees. Mack is the author of
Abduction: Human Encounters With Aliens and Passport to the Cosmos: Human
Transformation and Alien Encounters. ?That data operated like sulfuric
acid on my worldview,? he says in a film documentary. ?I couldn?t account
for this in any way with anything I had learned.?
In 1999 McNally and Susan Clancy, then a graduate student,
published the first of a series of landmark studies that tried to account
for such memories in a way that Mack could not. It has not been easy for
psychologists to design respectable, ethical, replicable laboratory
studies on recovered memory that their peers will accept. Critics shrug
off most research with the comment that lab studies say nothing about
repression of real-life trauma. Since the 1970s, for instance, Loftus has
been able to implant false memories in individuals in lab studiesthat
they were lost in a mall as children or that they hugged Bugs Bunny at
Disneyland (where there is no Bugs Bunny, because he?s not a Disney
character). She has also shown that implanted memories can influence
behavior. In one study, Loftus and her colleagues successfully led people
to believe that they once got sick eating either hard-boiled eggs or dill
pickles. Yet creating relatively innocuous memories in normal, healthy
people may not relate to the experience of trauma victims.
So Clancy, McNally, and a Harvard colleague, psychologist Daniel
Schacter, decided to initiate a study of women who claimed to have
recovered memories of sexual abuse. These women were at the white-hot
center of the memory wars, and yet, says Clancy, ?nobody was doing
laboratory research on memory formation in this population. We wanted to
know whether they were prone to creating false memories.? One of their
studies tested four groups of women: those who?d been sexually abused and
always remembered, those who believed they had been sexually abused but
had no memory of it, those who had recovered memories of sexual abuse,
and a control group who were certain they had never been abused. Each
subject was given a standard word-retrieval test, in which she was
presented with a list of semantically related words (rest, dream, nap,
tired). Each was then presented with the list again, but this time a new
word appeared on the list (such as sleep) similar in meaning to others on
the original list.
Those with recovered memories of abuse recalled having seen the missing
word on the first list 68 percent of the time, compared with only 38
percent for controls. The recovered-memory group scored significantly
higher than any of the other three on false remembering. ?There?s a
heightened tendency for false-memory formation in those who can recall
and visualize recovered memories,? McNally says.
Trauma therapists were outraged by the study. One of their objections:
Perhaps the trauma had been so horrific it was not only banished from
memory for years but also created memory defects that were now showing up
in lab tests. So McNally and Clancy recruited individuals with recovered
memories of alien abduction for the next study. Seven out of 11 of the
abductees in their experiment had reported (under hypnosis) that they had
their sperm or eggs extracted by aliens for breeding purposes. McNally
and Clancy figured that nobody could argue that this group of subjects
had post-traumatic stress disorder based on actual abuse during alien
abductions that impaired their ability to remember events accurately in
the lab. ?We thought we?d found the perfect study grouppeople who
clearly had created vivid, traumatic, false memories,? says Clancy.
The group produced significantly more false memories on the same
word-retrieval test, just as the women with recovered memories of sexual
abuse had. But that study also drew irefrom both abductees as well as
the general population. ?That totally shocked me,? says Clancy. ?I got
more hate mail, even from very educated people. I?d get letters asking me
who I was to say these people hadn?t been abducted.?
The results of their latest study are even more intriguing. McNally,
Clancy, and others at Harvard studied physiological stress in 10
abductees and 12 controls. Individuals were interviewed about traumatic,
neutral, and pleasant experiences. Thirty-second scripts were distilled
from the interviews and then recorded by Scott Orr, who runs a
psychophysiology lab at the Manchester VA Medical Center in New
Hampshire. Abductees listened to the recordings while hooked up to
electrodes that monitor sweat, heart rate, and muscle tension. This
method, using script-driven imagery, has been used many times to measure
post-traumatic stress disorder in war veterans. The abductees had a
significantly heightened stress response. Even McNally was surprised.
?Their reactivity was as great as real post-traumatic stress patients.
These people genuinely believe these events happened, and it?s reflected
in their physiology.?
McNally thinks that one reason abductees, who are on all other measures
sane and healthy individuals, are more vulnerable to false memories is a
trait called absorption: ?They score higher on measures of fantasy and
absorption, which is the ability, for instance, to get lost in daydreams
or be utterly entranced by a sunset. Their response to script-driven
imagery about pleasurable moments in their lives is also higher than
normal. So the upshot is, I think this stress response is a marker for
intense emotional memories in people with vivid imaging capacities.?
Could our cherished capacity to imagine, which gives life and art
richness, be a key to false memory?
People tend to view imagination as a purely mental activity, but it is
strongly linked to vision. The work of Stephen Kosslyn, a Harvard
psychologist, explains why.
Four floors down from McNally?s office at Harvard?s William James Hall
are Kosslyn?s spacious quarters. Precariously piled journals cover an
oversize wooden desk, along with a plastic replica of a brain, which
Kosslyn gladly takes apart for a visitor, pointing out the visual centers
at the very back. Those centers are the focus of his studies.
Kosslyn began conducting neuroimaging studies of the brain (PET and fMRI)
in 1990 and made a surprising discovery: Every area of the brain that is
activated when we see is also activated when we create an image in our
mind. ?It was absolutely amazing,? he says. ?The primary visual cortex,
the first visual area of the brain that registers input from the eyes, is
even activated by imagery with the eyes closed. That suggests the
opportunity for distortion is huge. The upside is, if imagery simulates
what you actually see in the brain, you can use it for memory or
reasoning or predicting. The downside is that you can become confused
about the source of images. That?s kind of scary.?
One study of eight easily hypnotized individuals found that when they
were simply asked to perceive a color, color areas in the brain were
activatedeven if they were looking at a gray scale. The control group
did not show this effect. Another study found that vivid visualization
accompanied by emotion triggered more activation in visual processing
systems than images alone did.
The human capacity for imagination is so great that sometimes people can
create delayed post-traumatic stress disorder even in the absence of
remembered traumas. Psychologist Richard Bryant of the University of New
South Wales in Australia studied individuals who had been in such a
serious accident that they?d been knocked unconscious and had no memory
of the event. A few of them later developed full-scale post-traumatic
stress disorder. When Bryant interviewed them, he found they had
reconstructed the accident by looking at news reports, photographs, and
listening to the accounts of friends. In an act of pure imagination, they
had cobbled together an accurate account that was so vividly pictured and
felt that it was powerful enough to produce post-traumatic stress
disorder.
Laboratory studies suggest that the brain has a unique sensitivity to
images. Psychologist Stephen Lindsay of the University of Victoria in
British Columbia published a study in Psychological Science in March that
demonstrates how pictures enhance the formation of false memories. He
showed 45 students a scenario purporting to describe an event in their
first-grade class. The false story told how an individual and a friend
got into trouble for putting Slime, a goolike substance, in their
teacher?s desk. When Lindsay added a class photo from the first grade to
the scenario, he found that two out of three students believed the false
event happened. Lindsay was astonished at the high rate of false-memory
reports: ?And the false memories were richly detailed. One student
commented, ?No way! I remembered it! That is so weird!??
?We tell ourselves stories in order to live,? wrote Joan Didion in The
White Album. Perhaps it?s not so baffling that what we can?t recall, we
invent. Memory is designed to filter the world and discard what is deemed
irrelevant, says psychologist Marcia Johnson of Yale University. That we
tend to home in on the details of an event is called weapon focuswe can
recall with grisly clarity the gun that was pointed at us by a robber,
but we may not remember his face or the other people in the store. If our
brains were perfect video cameras, we?d be paralyzed by information
overload. In the short story ?Funes, the Memorious,? Argentine writer
Jorge Luis Borges imagines just such a savant and writes, ?In the overly
replete world of Funes there were nothing but details.?
There is at least one real-life Funes, and behavioral neuroscientist
James McGaugh, at the University of California at Irvine, is studying
her: ?This woman came to me and said, ?My memory is too good.? For her,
it?s like looking at a Rolodex and seeing all the names at the same time.
It?s a flood of information, and it can make her life difficult.?
People never capture anything literally, says psychologist Henry L.
Roediger III of Washington University in St. Louis. ?Whenever you encode
an experience, you filter it through your own awareness. If we only
remembered the literal words of a conversation, we might miss the
meaning. If I tell you I?m really tired today because the baby was up all
night, you might remember that the baby cried all night. It?s an
inference. We?re always doing that, and that?s actually very
intelligent.? The odd thing, though, is that we usually don?t know we?re
confabulating. People have an unfounded confidence in their memories,
says Elizabeth Loftus. She notes that in one recent study she worked on,
three-quarters of the subjects reported having excellent memories. When
college students were asked about the Challenger explosion years after it
occurred, every single one remembered the spaceship blowing up, but many
got the details wrong. Thus, notes Marcia Johnson, when the brain strives
to re-create an event, it often grafts details of other memories onto it.
?The common wisdom was that once an experience was consolidated in
long-term memory, it was stable,? says neurobiologist Yadin Dudai of the
Weizmann Institute of Science in Israel. ?Some of us now think that a
memory may return to its embryonic state when it?s activated.? In the
lab, experiments point in both directions. Joseph LeDoux, the Henry and
Lucy Moses Professor of Science at New York University, was able to block
the process of encoding a conditioned fear response in rats by injecting
a drug, anisomycin, into their brains. The drug inhibits the synthesis of
proteins and thus blocks the formation, or consolidation, of a memory.
Twenty-four hours later, the rats? conditioned fear response seemed to
disappear. Yet a study recently published in the Proceedings of the
National Academy of Sciences found that the memory was only temporarily
blocked. This time, University of Pennsylvania researchers conditioned
rodents, treated them with anisomycin, and then examined them 21 days
later. They remembered the conditioned behavior.
Just to confuse the issue further, research that has just been published
finds that in rats conditioned to fear a shock to the foot, memory
formation and subsequent recall, or reconsolidation, are actually
separate processes, and thus established memories may be malleable and
sensitive to disruption. Although both an original memory and its
retrieval/reconsolidation may be blocked temporarily by anisomycin,
University of Cambridge psychologist Barry Everitt and his colleagues
found that the two processes depend on different chemicals within the
hippocampus. The initial formation of long-term memory requires a
chemical called brain-derived neurotrophic factor, while subsequent
recall depends on a transcription factor called Zif268. The processes are
related but fundamentally differentand so the researchers conclude that
repeated remembering does not create a duplicate of the original memory.
If we can isolate the chemicals involved in how memories are recalled, we
may someday have new drugs to help treat phobias, post-traumatic stress
disorder, and intrusive memories.
In real life, McNally says, memories do change. Yale University
psychiatrist Steven Southwick surveyed Gulf War veterans first one month,
then two years after traumatic events. About half the veterans who
checked off events on the first survey failed to check off some of the
same events after two years had passed. The timbre and quality of
memories changes over time too. McNally gave a questionnaire to personnel
6 months after a fatal shooting at a grammar school in suburban Chicago.
The same questionnaire was given again 18 months after the shooting.
?Each person remembered the event differently at 18 months than at 6
months,? says McNally. At the second interview, those who had more severe
symptoms of post-traumatic stress disorder recalled the event as more
harrowing, while memories were recalled as less harrowing by those who
had recovered.
We create our memories even as they create usa Möbius strip, an Escher
print, a double helix, if you will, from which the blueprint of self
emerges. It?s both dazzling and chilling to realize that the narrative
arc of our lives relies on a phenomenon that is by turns robust,
fallible, malleable, potent, slippery, inventive, and above all,
powerfully yoked to emotion.
If we are storytellers, even inaccurate ones, how does that serve us?
?What has been missing from all the theories of false memory,? says
Clancy, ?is the desire for meaning. I think psychologists are tone deaf
to this. It?s a very important ideological factor in the development of
any belief. Alien abductees talk about the fact that they don?t feel
alone in the universe any longer.? When McNally and Clancy asked
abductees if they were glad they?d had these experiences, ?we only had
one person say no. Everyone else said it was initially disorienting and
frightening but that they eventually put it all in a spiritual
perspective.?
So how and why would an individual develop a story line as unusual as
abduction? Are there any common ingredients? Part of the answer may
derive from a physiologically dramatic and terrifying phenomenon called
sleep paralysis. In classic sleep paralysis, a person wakes early from a
dream and is unable to move (as is standard during REM sleep). In many of
these cases, people also generate vivid dream images called hypnopompic
hallucinations. Many alien abductees experience sleep paralysis, and if
they don?t understand the phenomenon and believe their otherworldly
hallucinations are real, says McNally, they may seek out therapy,
hypnosis, or bodywork, thereby ?recovering? additional memories. ?These
folks are very open to what we might call New Age beliefs, such as
reincarnation, energy therapies, astrology, reincarnation, and
telepathy.?
Will Beuche sees it this way: ?I won?t call abduction a spiritual
experience, but by its very nature it casts you into reflection about
your existence . . . you feel you?re behind the scenes of a theater, of
an incredible play . . . this play we?re all in.?
But he might as well be talking about the phenomenon of memory itselfin
which we somehow weave and unweave ourselves by our own hand.
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PUTTING FREUD TO THE TEST: CAN MEMORIES BE REPRESSED?
Freud?s theory of repression has intrigued psychologists since the 1930s,
but nobody has proved it exists. Cognitive neuroscientist Michael
Anderson, who runs a memory lab at the University of Oregon, believes
he?s got the goods. ?You don?t have to subscribe to highly specialized
mechanisms like the ones Freud might have proposed,? says Anderson. ?You
can explain it with very well-respected ideas in neuroscience and
psychology.? For instance, he says, we all exercise what is known as
executive control. We can focus our attention on one thing and ignore
distractions. Scientists have shown a sequence of letters to individuals
and told them that each time they see a letter, they should press a
keyexcept when the letter X appears. ?These are called go/no-go
procedures,? says Anderson. ?They?re set up so the individual gets into a
rhythm of seeing letters and pressing the key, and when X appears, they
have to stop themselves.? Monkey studies have shown that the no-go
response is associated with specific regions of the frontal cortex.
To test a similar paradigm in memory, Anderson created a think/no-think
procedure for recalling word pairs. In a study they found that the
subjects, when prompted, could push the second word in a learned word
pair out of awareness, which made it harder to recall later. Recently,
Anderson and his colleagues used the same think/no-think procedure along
with fMRI. In a study published in Science in January 2004, they found
that suppressing recollection reduced the activity of the hippocampus,
the small organ that shuttles short-term memories into long-term storage.
They also found greater activity in many areas of the prefrontal cortex,
the same areas that are active in go/no-go procedures.
Daniel Schacter, a Harvard University psychologist, warns that Anderson?s
results do not address the issue of whether traumatic memories can be
repressed. He says that Anderson?s work fits Freud?s first definition of
repressionan intentional attempt to banish distressing experiences from
conscious awareness. Freud later used the term to refer to a defense
mechanism that operated beyond a person?s awareness. That model of
repression has never been proved to exist.
Psychologist Henry L. Roediger III of Washington University in St. Louis
says he has failed to replicate Anderson?s work. Anderson responds that
Roediger was using a slightly different and earlier design and that the
results have been replicated elsewhere. Roediger says: ?If repression
hinges on this teeny-weeny change, then it is not very robust. I?m not
saying the effect can?t be obtainedI?m just saying it?s hard to obtain.?
?I don?t subscribe to the view that repression needs to be unconscious,
complete, or permanent,? says Anderson. ?It can be a process that
requires effort over time and may lead people to forget all or part of an
unwanted experience. Even if somebody doesn?t forget the Holocaust, for
instance, they may forget details over time. This may actually help. We
need to find out how people cope with distressing memories. That?s why
this is a pretty damned important topic to
research.? J. N.
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