- You were abducted by aliens, you saw Bugs Bunny at Disneyland,
- and then you went up in a balloon. Didn't you?
-
- Alan Alda had nothing against hard-boiled eggs until
last spring. Then the actor, better known as Hawkeye from M*A*S*H, paid
a visit to the University of California, Irvine. In his new guise as host
of a science series on American TV, he was exploring the subject of memory.
The researchers showed him round, and afterwards took him for a picnic
in the park. By the time he came to leave, he had developed a dislike of
hard-boiled eggs based on a memory of having made himself sick on them
as a child - something that never happened.
-
- Alda was the unwitting guinea pig of Elizabeth Loftus,
a UCI psychologist who has been obsessed with the subject of memory and
its unreliability since Richard Nixon was sworn in as president. Early
on in her research, she would invite people into her lab, show them simulated
traffic accidents, feed them false information and leading questions, and
find that they subsequently recalled details of the scene differently -
a finding that has since been replicated hundreds of times.
-
- More recently, she has come to believe that lab studies
may underestimate people's suggestibility because, among other things,
real life tends to be more emotionally arousing than simulations of it.
So these days she takes her investigations outside the lab. In a study
soon to be published, she and colleagues describe how a little misinformation
led witnesses of a terrorist attack in Moscow in 1999 to recall seeing
wounded animals nearby. Later, they were informed that there had been no
animals. But before the debriefing, they even embellished the false memory
with make-believe details, in one case testifying to seeing a bleeding
cat lying in the dust.
-
- "We can easily distort memories for the details
of an event that you did experience," says Loftus. "And we can
also go so far as to plant entirely false memories - we call them rich
false memories because they are so detailed and so big."
-
- She has persuaded people to adopt false but plausible
memories - for instance, that at the age of five or six they had the distressing
experience of being lost in a shopping mall - as well as implausible ones:
memories of witnessing demonic possession, or an encounter with Bugs Bunny
at Disneyland. Bugs Bunny is a Warner Brothers character, and as the Los
Angeles Times put it earlier this year, "The wascally Warner Bros.
Wabbit would be awwested on sight", at Disney.
-
- Elizabeth Loftus' research has obvious implications for
the reliability of eyewitness testimony. And it was as a result of her
findings that in 1994 she co-wrote her book, The Myth of Repressed Memory,
and took a strong stand in the recovered memory debate of the 90s, for
which she was reviled by those who claimed to have uncovered repressed
memories of abuse - alien, sexual or otherwise.
-
- The American Psychological Association (APA) now takes
the line that most people who were sexually abused as children remember
all or part of what happened to them, and that it is rare (though not unheard
of) that people forget such emotionally charged events and later recover
them. But it states that, "Concerning the issue of a recovered versus
a pseudomemory, like many questions in science, the final answer is yet
to be known." And the debate simmers on. Several new lines of evidence
suggest that the interaction between memory and emotion is more complex
than was thought. Powerful emotions, it seems, can both reinforce and weaken
real memories. We may be able to actively degrade painful memories. And
false memories, once accepted, can themselves elicit strong emotions and
thereby mimic real ones.
-
- To try to tease apart these complex relationships, the
psychologist Daniel Wright and his colleagues at the University of Sussex
have been looking into what it is that makes some people more susceptible
to false memories than others. On average, studies show that around a third
of those subjected to the "misinformation effect" wholly or partially
adopt a false memory, but it seems to depend on both the person and the
memory. Alan Alda swallowed the hard-boiled egg story, to the extent that
he declined to eat one at the UCI picnic, but he wasn't taken in by Bugs
Bunny in Disneyland. In one study published last year, 50% of volunteers
were persuaded they had taken a ride in a hot-air balloon when they had
not. But when Kathy Pezdek of the Claremont Graduate University, California,
tried to make people believe they had received a rectal enema, she met
with almost universal resistance.
-
- Amid all this variability, Wright's group did find one
significant correla tion - though it was not dramatic: those who were more
vulnerable to false memories also tended to suffer more frequent lapses
in attention and memory. The trouble is, he says, "People who have
been traumatised also tend to score higher on tests of lapses in memory."
Their traumatic experiences may contribute to their forgetfulness, but
their forgetfulness may lay them open to memory distortion - so true and
false become harder to disentangle.
-
- Among the symptoms suffered by victims of post-traumatic
stress disorder (PTSD) are chilling flashbacks. But, says Michael Anderson
of the University of Oregon, "People who suffer PTSD represent a very
small fraction of the people who experience trauma. The great majority
of people who experience trauma never develop PTSD and eventually are able
to adapt in the face of these events." He argues that they do so by
suppressing the memory, and that this suppression gradually erases it.
-
- Two years ago, Anderson's group showed that people who
deliberately try to keep a word out of their mind find it harder to recall
later than if they had not suppressed it. Counter- intuitively, this form
of forgetting seems more likely to occur when people are confronted by
reminders of the very memory they want to avoid. Anderson says an extreme
example of this might be a child who is forced to live with an abusing
care-giver, and must put the memory of abuse to one side in order to interact
with that care-giver. "If people continue to work at it, the amount
of forgetting grows with repetition and time," he says.
-
- At the annual meeting of the US Society for Neuroscience
in New Orleans last month, Anderson's group presented new data on how this
"motivated forgetting" might arise in the brain. When people
tried to suppress memories for certain words while having their brains
scanned in a magnetic resonance imaging machine, not only did the researchers
see a dampening of activity in the hippocampus, a structure known to be
critical for memory formation, but the frontal cortex was highly active.
Since the frontal cortex is important for conscious control, they believe
that neurons here may be suppressing the representation of the unwanted
word in the hippocampus, and in the process impairing its memory.
-
- However, Anderson admits that his experiments ignore
the effect of a memory's emotional intensity on a person's ability to suppress
it. And there is plenty of evidence that memory for emotionally charged
events can be enhanced - albeit at a cost. Also last month, Bryan Strange
of the Wellcome department of imaging neuroscience at University College
London and colleagues showed that people were more likely to remember a
word if it was emotionally arousing - "murder" or "scream",
say - than if it was neutral. And the words most likely to be forgotten
were neutral ones presented just before emotionally arousing ones. The
effect was more pronounced in women than in men, and both the enhanced
memory for the emotional word and the forgettability of the preceding neutral
one could be reversed by dosing the volunteers in advance with the drug
propranolol.
-
- Propranolol, a commonly prescribed beta-blocker, interferes
with the neurochemical pathway thought to be responsible for making emotionally
arousing events more memorable - the beta-adrenergic system - and it has
already been used experimentally in the treatment of patients with PTSD.
In one study, published in October, Guillaume Vaiva of the University of
Lille and colleagues offered prop- ranolol to victims of assault or motor
accidents shortly after their traumatic experience, and then invited them
back for psychological testing two months later. On their return, almost
all the patients exhibited some symptoms associated with PTSD, but they
were twice as severe among those who had not taken the drug.
-
- The finding that propranolol can be effective at blocking
memory when given after an event as well as before is important because,
as Loftus explains, "In the real world you can't be there to exert
your manipulations right at the time an event is happening, but you can
get on the scene later." It has been proposed that propranolol should
be offered to victims of rape as a standard measure to prevent them developing
PTSD. But could it also be used to erase false memories - for instance,
"recovered" memories of alien abduction - that nevertheless elicit
all the physiological responses associated with harrowing, real memories?
-
- "If the formation of false memories depends on beta-adrenergic
activation, then it would seem very possible that propranolol administration
could affect them," says the UCI neuro- biologist Larry Cahill, who
has also investigated the effects of the drug in PTSD patients. But Ray
Dolan of UCL, a co-author with Bryan Strange of the study on memory for
emotional words, points out that not all false memories have a common basis.
If they are interpolations into gaps in memory, such as the gap that opened
up before the presentation of an emotionally arousing word, or possibly
the gap into which Alan Alda inserted a memory of having over-indulged
in eggs, then it is conceivable the drug would work. But, says Dolan, "Other
classes of false memory, for example, where the memories are fantasies
or out-and-out fabrications, would be immune to propranolol."
-
- The idea of doctors having the power to wipe the memory
clean sends shivers down many people's spines. False memories could safely
be erased, perhaps, assuming there was a reliable way of differentiating
them from true ones. Although brain-imaging techniques highlight some differences
in patterns of brain activation when a person recalls a true as opposed
to a false memory, these are statistical differences only. "We are
so far away from being able to use these techniques to reliably classify
a single memory as being real or not real," says Loftus, "Yet
that is what the courts have to do."
-
- True memories, too, can get out of control and become
destructive, leading to PTSD and other anxiety disorders. But they start
out as an important self-defence mechanism - teaching you, for instance,
that too many hard-boiled eggs are bad for you. Erasing them completely
could be dangerous.
-
- In the end, says Loftus, it will come down to personal
choice. "What would you rather be in the world, sadder but wiser,
all too well remembering the horrors of your past and feeling depressed,
or perhaps not remembering them very much and being a little happier?"
-
- Further reading
-
- The Myth of Repressed Memory by Dr Elizabeth Loftus and
Katherine Ketcham, 1996 paperback (St Martin's Press, New York). ISBN 0312141238
-
- American Psychological Association website with links
to questions and answers about memories of childhood abuse: www.apa.org/pubinfo/
-
- Suppressing unwanted memories by executive control by
Michael C Anderson and Collinn Green, Department of Psychology, University
of Oregon, 2001 (Nature, 410 [6826], 366-9)
-
-
- EducationGuardian.co.uk © Guardian Newspapers Limited
2003
-
-
- Comment
- From Hazel
- 12-8-3
-
- Neuroscientists admit that by administering beta-blockers
like Propranolol, they can induce false memories in susceptible people,
particularly those who have suffered a traumatic experience, (torture)
leaving them "open to memory distortion - so true and false become
harder to disentangle" but for what purpose?
-
- I can't think of a single positive application for 'False
Memory Syndrome' except perhaps - "doctor, make me imagine I tried
on a size 10 dress today, and it fitted" - which would be a real confidence
booster for fat ladies. It could be used to suppress recollections of a
distressing ordeal, but that is not healthy, it is far better to confront
your psychological demons.
-
- However, I can think of numerous scenarios where a false
memory could be implanted for sinister reasons, such as - I was molested
by Sai Baba, when I wasn't, aliens abducted me, when they didn't, or I
killed two schoolgirls, when I haven't! It could also account for many
other misconceptions like, why Neil Armstrong is convinced he set foot
on the lunar surface - or why George Bush thinks Saddam Hussein was responsible
for September 11th.
-
- Elizabeth Loftus, a UCI psychologist explains, "In
the real world you can't be there to exert your manipulations right at
the time an event is happening, but you can get on the scene later"
- when a patsy is in custody and subjected to "treatment" like
Ian Huntley, who was a perfect candidate, having previously had a nervous
breakdown after wrongful arrest for rape and is now on trial for murder.
-
- "We can easily distort memories for the details
of an event that you did experience and we can also go so far as to plant
entirely false memories" says Loftus, "we call them rich false
memories because they are so detailed and so big." Mind-control has
come a long way since Nazi concentration camp experiments, in fact, all
the way to South America with Dr. Mengele and into the USA via the CIA's
Operation Paperclip, where it is now respectable medical practice.
-
- This means that anyone could be made to admit to anything
and no "confession" can ever be trusted again. So, maybe Bali's
"laughing bomber" wasn't so funny after all - or Moazzam Begg's
ridiculous admission from Camp Delta, of having planned to spray the Houses
of Parliament with anthrax, because it is so far-fetched and would be no
easy feat for an ordinary father of four from Birmingham.
-
- With 'False Memory Syndrome' at the disposal of "evil
geniuses" we are all "Slobodan Guantanamo" now! Therefore,
when you see my face on the front page with the Headline: - "I PLOTTED
TO THROTTLE THE QUEEN" (with my bare hands, at her next walkabout)
Ð think twice - before congratulating me. Nothing is what it seems
and everything is a lie.
-
- Hazel
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