...

THINKING CRITICALLY Can Traumatic Memories Be Repressed Then Recovered

by taratuta

on
Category: Documents
112

views

Report

Comments

Transcript

THINKING CRITICALLY Can Traumatic Memories Be Repressed Then Recovered
Percentage of words recalled
230
Chapter 6
100
90
80
70
Recall when given
item categories as
retrieval cues
60
50
40
30
Initial recall
20
Memory
first list were still in long-term memory; they had not been pushed out, but the participants could not remember them without appropriate retrieval cues. In short, faulty
retrieval caused the original forgetting. Putting more and more information in longterm memory may be like putting more and more CDs in a storage cabinet. Although
none of the CDs disappears, it becomes increasingly difficult to find the one you are
looking for.
Some theorists have suggested that all forgetting from long-term memory is due to
retrieval failure (Ratcliff & McKoon, 1989). Does this mean that everything in longterm memory remains there for life, even if you cannot always, or ever, recall it?
No one yet knows for sure, but as described in the next section, this question lies at
the heart of some highly controversial court cases.
10
1
2
3
4
5
Number of intervening lists
Source: Tulving & Psotka (1971).
FIGURE
6.12
Retrieval Failures and Forgetting
Tulving and Psotka (1971) found that people’s ability to recall a list of items was
strongly affected by the number of other
lists they learned before being tested on
the first one. When retrieval cues were
provided on a second test, however,
retroactive interference from the intervening lists almost disappeared.
LINKAGES
Do forgotten memories
remain in the subconscious?
(a link to Consciousness)
I
T H I N K I N G C R I T I C A L LY
n 1989, Eileen Franklin told California
police that when she looked into her young
Can Traumatic Memories Be
daughter’s eyes one day, she suddenly
remembered seeing her father kill her childRepressed, Then Recovered?
hood friend more than twenty years earlier.
On the basis of her testimony about this
memory, her father, George Franklin, Sr., was sent to prison for murder (Loftus &
Ketcham, 1994).
■ What am I being asked to believe or accept?
The prosecution in the Franklin case successfully argued that Eileen had recovered her
long-buried memory of a murder. Similar arguments in other cases tried in the early
1990s also resulted in imprisonment as now-adult children claimed to have recovered
childhood memories of physical or sexual abuse at the hands of their parents. The juries
in these trials accepted the assertion that all memory of shocking events can be
repressed, or pushed into an inaccessible corner of the mind where, for decades, subconscious processes keep it out of awareness, yet potentially subject to accurate recall
(Hyman, 2000). Jurors are not the only ones who believe in this phenomenon. A few
years ago a large American news organization reported that the United States had illegally used nerve gas during the war in Vietnam. This story was based, in part, on a
Vietnam veteran’s account of recovered memories of having been subjected to a nerve
gas attack.
■ Is there evidence available to support the claim?
Proponents of the recovered-memory argument point to several lines of evidence to
support their claims. First, as discussed in the chapter on consciousness, a lot of mental activity occurs outside of awareness (Kihlstrom, 1999). Second, research on implicit
memory shows that our behavior can be influenced by information of which we are
unaware (Betch et al., 2003; Kouider & Dupoux, 2005; Schacter, Chiu, & Ochsner,
1993). Third, research on motivated forgetting suggests that people may sometimes be
able to willfully suppress information so that it is no longer accessible on a later memory test (Anderson & Green, 2001). Even suppressing one’s emotional reactions to
events can interfere with memories of those events (Richards & Gross, 2000). And people appear more likely to forget unpleasant rather than pleasant events (Erdelyi, 1985).
In one study, a psychologist kept a detailed record of his daily life over a six-year period.
When he later tried to recall these experiences, he remembered more than half of the
positive events but only one-third of the negative ones (Waagenaar, 1986). In another
study, 38 percent of women who, as children, had been brought to a hospital because
of sexual abuse did not report the incident as adults (Williams, 1994). Fourth, retrieval
cues can help people recall memories that had previously been inaccessible to conscious
awareness (Andrews et al., 2000; Landsdale & Laming, 1995). For example, these cues
231
Forgetting
have helped soldiers remember for the first time the circumstances under which they
had been wounded many years before (Karon & Widener, 1997). Finally, there is the
confidence with which people report recovered memories; they say they are just too
vivid to be anything but real.
■ Can that evidence be interpreted another way?
Those who are skeptical about repressed memories know that subconscious memory
and retrieval processes exist (Kihlstrom, 1999). They also recognize that, sadly, child
abuse and other traumas are all too common. But to these psychologists, the available
evidence is not strong enough to support the conclusion that traumatic memories can
be repressed and then accurately recalled. Any given “recovered” memory, they say, may
actually be a distorted, or constructed, memory (Clancy et al., 2000; Hyman, 2000;
Loftus, 1998). Our recall of past events is affected by what happened at the time, what
we knew beforehand, and everything we have experienced since. The people who
“remembered” nonexistent books in an office inadvertently used their prior knowledge
of what is usually in graduate students’ offices to construct a false memory for the
books. Similarly, the “recovered memory” of the Vietnam veteran mentioned earlier
appears to have no basis in fact; the news story about the alleged nerve gas attack was
later retracted.
As we saw in the Focus on Research section, false memories—distortions of actual
events and the recall of events that didn’t actually happen—can be just as vivid as real,
accurate memories, and people can be just as confident in them (Brainerd & Reyna,
2005; Brainerd et al., 2003; Loftus, 2004; Nourkova, Bernstein, & Loftus, 2004; Roediger
& McDermott, 2000). Most of us have experienced everyday versions of false memories. It is not unusual to “remember” turning off the coffeepot or mailing the rent check,
only to discover later that we didn’t. Researchers have demonstrated that false memories can occur in relation to more emotional events, too. In one case study, a teenager
named Chris was given descriptions of four incidents from his childhood and asked to
write about each of them every day for five days (Loftus, 1997a). One of these incidents—being lost in a shopping mall at age five—never really happened. Yet Chris eventually “remembered” this event, and even added many details about the mall and the
stranger whose hand he was supposedly found holding. He also rated this (false) memory as being more vivid than two of the other three (real) incidents he wrote about.
Similar results occurred in about half of seventy-seven child participants in more recent
case studies (Porter, Yuille, & Lehman, 1999). The same pattern of results has appeared
in formal experiments on the planting of emotion-laden false memories (Hyman &
Pentland, 1996; Loftus & Pickrell, 1995). Researchers have been able to create vivid and
striking, but completely false, memories of events that people thought they experienced
when they were one day old (DuBreuil, Garry, & Loftus, 1998). In other experiments,
children who were repeatedly asked about a nonexistent trauma (getting a hand caught
in a mousetrap) eventually developed a clear and unshakable false memory of experiencing it (Ceci et al., 1994). Some people will even begin to avoid a certain food after
researchers create in them a false memory of having been ill after eating that food as
a child (Bernstein et al., 2005).
In other words, people sometimes have a difficult time distinguishing between what
has happened to them and what they have only imagined, or have come to believe, has
happened (Garry & Polaschek, 2000; Henkel, 2004; Johnson & Raye, 1998; Mazzoni &
Memon, 2003; Zaragoza et al., 2001). Some studies have found that people who are
fantasy-prone, who easily mistake real and imagined stimuli, and who tend to have
lapses in attention and memory are more likely than others to develop false memories
and possibly more likely to report the recovery of repressed memories (McNally, 2003;
McNally et al., 2000a, 2000b, 2005; Porter et al., 2000). Two other studies have found
that women who have suffered physical or sexual abuse are more likely to falsely
remember words on a laboratory recall test (Bremner, Shobe, & Kihlstrom, 2000;
Zoellner et al., 2000). This tendency appears strongest among abused women who show
signs of posttraumatic stress disorder (Bremner et al., 2000). Another study found that
232
Chapter 6
Memory
EXPLORING MEMORY PROCESSES
Elizabeth Loftus (at the far right) is
shown here with her students and Alan
Alda, who filmed a documentary about
her research. Loftus and other cognitive
psychologists have demonstrated mechanisms through which false memories
can be created. They have shown, for
example, that false memories appear
even in research participants who are
told about them and asked to avoid them
(McDermott & Roediger, 1998). Their
work has helped to focus scientific
scrutiny on reports of recovered memories, especially those arising from contact
with therapists who assume that most
people have repressed memories of
abuse.
the tendency to have false memories on a word recall task was greater in women who
reported recovered memories of sexual abuse than in nonabused women or in those
who had always remembered the abuse they suffered (Clancy et al., 2000). False memories on this laboratory recall task are also more common among people who claim to
have been abducted by space aliens than among other people (Clancy et al., 2002).
Why would anyone “remember” a trauma that did not actually occur? Elizabeth
Loftus (1997b) suggests that, for one thing, popular books such as The Courage to Heal
(Bass & Davis, 1994) and Secret Survivors (Blume, 1998) may lead people to believe that
anyone who experiences guilt, depression, low self-esteem, overemotionality, or any of
a long list of other problems is harboring repressed memories of abuse. This message,
says Loftus, is reinforced and elaborated by some therapists, particularly those who specialize in using guided imagination, hypnosis, and other methods to “help” clients
recover repressed memories (Lindsay et al., 2004; Polusny & Follette, 1996; Poole et al.,
1995). In so doing, these therapists may influence their clients to construct false memories by encouraging them to imagine experiencing events that might never have actually occurred or that occurred only in a dream (Mazzoni & Loftus, 1996; Olio, 1994).
As one client described her therapy, “I was rapidly losing the ability to differentiate
between my imagination and my real memory” (Loftus & Ketcham, 1994, p. 25). To
such therapists, a client’s failure to recover memories of abuse or refusal to accept that
they exist is evidence of denial of the truth (Loftus, 1997a; Tavris, 2003).
The possibility that recovered memories might actually be false memories has led to
dismissed charges or not-guilty verdicts for defendants in some repressed memory
cases. In other cases, previously convicted defendants have been released. (George
Franklin’s conviction was overturned, but only after he spent five years in prison.) Concern over the potential damage resulting from false memories prompted the establishment in 1992 of the False Memory Syndrome Foundation, an organization of families
affected by abuse accusations stemming from allegedly repressed memories. More than
a hundred of these families (including George Franklin’s) have filed lawsuits against
hospitals and therapists. In 1994, California winery executive Gary Ramona received
$500,000 in damages from two therapists who had “helped” his daughter recall alleged
sexual abuse at his hands. A more recent suit led to a $2 million judgment against
a Minnesota therapist whose client discovered that her “recovered” memories of
childhood were false; a similar case in Wisconsin brought a $5 million judgment against
two therapists. And an Illinois case resulted in a $10.6 million settlement and the
233
Forgetting
suspension of the license of the psychiatrist who had “found” his patient’s lost memories (Loftus, 1998).
■ What evidence would help to evaluate the alternatives?
Evaluating reports of recovered memories would be easier if we had more information
about whether it is possible for people to repress memories of traumatic events. If it is
possible, we also need to know how common it is and how accurate recovered memories might be. So far we know that some people apparently forget intense emotional
experiences, but that most people’s memories of them are vivid and long-lasting
(Alexander et al., 2005; Goodman et al., 2003; Pope et al., 1998; Strongman & Kemp,
1991). Some are called flashbulb memories because they preserve particular experiences
in great detail (Brown & Kulik, 1977). In fact, many people who live through trauma
are unable to forget it, though they wish they could (Henig, 2004). In the sexual abuse
study mentioned earlier, for example (Williams, 1994), 62 percent of the victims
recalled as adults the trauma that had been documented in their childhoods. A similar
study of a different group of adults found that about 92 percent of them recalled their
documented childhood abuse (Alexander et al., 2005; Goodman et al., 2003). The true
recall figures might actually be even higher in such studies, because some people who
remember abuse may not wish to talk about it. In any case, additional studies like
these—studies that track the fate of memories in known abuse cases—would not only
help estimate the prevalence of this kind of forgetting but also might offer clues as to
the kinds of people and events most likely to be associated with it.
It would also be valuable to know more about the processes through which repression might occur. Is there a mechanism that specifically pushes traumatic memories
out of awareness, then keeps them at a subconscious level for long periods? Despite
some suggestive results (Anderson & Green, 2001; Anderson et al., 2004; DePrince &
Freyd, 2004), cognitive psychologists have so far not found reliable evidence for such a
mechanism (Bulevich et al., 2006; Geraerts et al., 2006; Loftus, 1997a; McNally, Clancy, &
Schacter, 2001; McNally, 2003; McNally et al., 2000a; Pope et al., 1998).
■ What conclusions are most reasonable?
An objective reading of the research evidence suggests that the recovery of traumatic
memories is at least possible but that the implantation of false memories is also
possible—and has been demonstrated repeatedly in controlled experiments. With this
in mind, it is not easy to decide whether any particular case is an instance of recovered
memory or false memory, especially when there is no objective corroborating evidence
to guide the decision.
The intense conflict between those who uncritically accept claims of recovered
memories and those who are more wary about the accuracy of such claims reflects a
fundamental disagreement about evidence (Tavris, 2003). To many therapists who deal
daily with victims of sexual abuse and other traumas, clients’ reports constitute stronger
proof of recovered memories than do the results of laboratory experiments. Client
reports are viewed with considerably more skepticism by psychologists who engage in,
or rely on, empirical research on the processes of memory and forgetting (Loftus, 2003,
2004; Pope, 1998). They would like to have additional sources of evidence, including
brain activity “signatures” that might distinguish true memories from false ones (e.g.,
Cabeza et al., 2001; Slotnick & Schacter, 2004).
So whether or not you believe a claim of recovered memory may be determined by
the relative weight you assign to reports of personal experiences versus evidence from
controlled experiments. Still, the apparent ease with which false memories can be created should lead judges, juries, and the general public to exercise great caution before
accepting unverified memories of traumatic events as the truth. At the same time, we
should not automatically reject the claims of people who appear to have recovered
memories. Perhaps the wisest course is to use all the scientific and circumstantial
Fly UP