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Description
Figure 6.13 Semantic Networks
Source: Collins, A. M., & Loftus, E. F. (1975). A spreading-activation
theory of semantic processing. Psychological Review, 82(6), 407–428.
https://doi.org/10.1037/0033-295X.82.6.407
A good deal of research supports the notion that memories are stored in semantic
networks. When subjects are given a list of 60 words that fall into four categories
(animals, professions, names, fruits)—even if the words are presented in a mixed
order—subjects later tend to recall them in clusters. In other words, retrieving tiger is
more likely to trigger one’s memory for baboon than for dentist, Jason, or banana
(Bousfield, 1953; Pacheco & Verschure, 2017; Romney, Brewer, & Batchelder, 1993).
Neural Bases of Long-Term Memory
Is it possible to pinpoint a site in the brain that houses these associations? Do
memories leave a physical trace that can actually be “seen”? Are there drugs that we
can take to improve our memory? Although led astray, at times, by exciting
developments, neuroscientists have long been intrigued by such possibilities
(Josselyn, Kohler, & Frankland, 2017; Squire & Schacter, 2002).
In one promising development, neurosurgeon Wilder Penfield reported that he
had triggered long-forgotten memories in humans through brain stimulation. In the
1940s, Penfield was treating epileptic patients by removing portions of their brains. To
locate the damage, he stimulated different cortical areas with a painless electrical
current. Sometimes, his patients—who were awake during the procedure—would
“relive” long-lost events from the past. For example, one woman said she heard a
mother calling her child when a certain spot was stimulated. From reports like this,
Penfield concluded that experience leaves a permanent “imprint” that can be played
back years later as though there was a tape recorder in the brain (Penfield & Perot,
1963). This observation sparked a great deal of excitement until cognitive
psychologists scrutinized the data and made two sobering discoveries. First, the
phenomenon itself was very rare, reported by only a handful of Penfield’s 1,100
patients. Second, the “flashbacks” were explained by some researchers as dreamlike
illusions, not actual memories (Loftus & Loftus, 1980; Neisser, 1967). However, nine
rodent experiments conducted between 2012 and 2016 (as reviewed by Josselyn et
al., 2017) have demonstrated that electrical “stimulation is sufficient to induce
behavioral memory expression” (p. 4652).
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Penfield’s work is said to have inspired today’s researchers’ hot pursuit of the
engram—a term used to describe a physical memory trace. There are two objectives
in this endeavor: (a) to locate the anatomical structures in the brain where memories
are stored and (b) to understand the neural and biochemical changes that
accompany memories. Let’s now examine some recent developments along these
lines.
Where is the “Engram”?
Karl Lashley (1950) pioneered the search for memory traces in the brain. For 30
years, Lashley trained rats to run a maze, removed different structures from their
brains, and then returned the rats to the maze to test their memory. No matter what
structures he removed, however, the rats recalled at least some of what they had
learned. Eventually, Lashley was forced to conclude that memories do not reside in
any specific location.
In 1953, a 27-year-old man, Henry Molaison (referred to as H.M.), underwent
brain surgery for severe epileptic seizures. Two holes were drilled into the patient’s
skull above the eyes, and through a silver straw the surgeon removed parts of both
temporal lobes and sucked out the entire hippocampus—a curved pinkish-gray
structure in the limbic system (illustrated in Figure 6.14). The operation succeeded in
controlling the man’s seizures. But something was terribly wrong. What made H.M.
one of the most famous neurology cases of all time is that the surgery had an
unexpected side effect: It produced anterograde amnesia, an inability to form new
long-term memories. (This should not be confused with retrograde amnesia, which
is an inability to retrieve long-term memories from the past.)
hippocampus. A portion of the brain in the limbic system that plays a key role in
encoding and transferring new information into long-term memory.
anterograde amnesia. A memory disorder characterized by an inability to store
new information in long-term memory.
retrograde amnesia. A memory disorder characterized by an inability to retrieve
long-term memories from the past.
Description
Figure 6.14 The Hippocampal Region
H.M. still recalled the people, places, and events from before the surgery. He also
performed as well as before on IQ tests and could still read, write, and solve
problems so long as he stayed focused on the task. But he could not retain new
information. He would meet someone new but then forget the person; or he would
read an article without realizing that he had read it before; or he would not know what
he ate for his last meal. One year after his family moved, H.M. still did not know their
new address. It was as if new information “went in one ear, out the next” (Milner,
Corkin, & Teuber, 1968; Scoville & Milner, 1957). In his 70s, H.M. was the subject of
Memory’s Ghost, a book by Philip Hilts (1995). Hilts, who spent a great deal of time
with H.M., tells of a remarkable experience. For H.M., he says, “Each moment is a
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surprise, a new puzzle to be worked out from a quick glance at the paltry evidence at
hand as it comes rapidly upon him” (p. 139).
H.M.’s case is important for two reasons. First, he exhibited a very specific
information-processing deficit. He could bring new material into short-term memory
and he could retrieve long-term memories that were previously stored. But he could
not form new long-term memories.
The second reason H.M.’s case is important is that it was the first to prove what
Lashley could not—that localized lesions in the brain have disruptive effects on
memory. Specifically, H.M.’s case and the work of Brenda Milner revealed that the
hippocampus (and perhaps structures such as the amygdala and thalamus) plays a
pivotal role (Josselyn et al., 2017). Recent studies in animals and humans have since
confirmed the point: The hippocampus is essential for the explicit recollection of
newly acquired information. Hippocampal lesions that mimic H.M.’s surgery produce
a similar impairment in rats (Zhou, Zhou, & Xu, 2016), monkeys (Blue, Kazama, &
Bachevalier, 2013), and other animals (Gafford, Parsons, & Helmstetter, 2011;
Hampton & Shettleworth, 1996; Sherry, 1992; Squire & Schacter, 2002).
Is all of memory stored in the hippocampus? No. When this structure is surgically
removed from monkeys, they lose most of their recall for events of the preceding
month, but their more distant memories remain intact (Squire & Zola-Morgan, 1991).
And among humans, older adults with a shrunken hippocampus are impaired in their
ability to recall new words and pictures, but they can still revisit past events (Golomb
et al., 1993). For example, persons with Alzheimer’s disease, a progressive memory
disorder, experience extreme deterioration of their hippocampus (Adler et al., 2018).
One result is that they suffer from a striking loss of memory for new information.
However, in a study where they were placed in an apartment—called the
reminiscence apartment—fully decorated and stocked with items from the 1950s,
persons with Alzheimer’s recalled more of their past events and with increased detail
than when in their everyday setting (Miles, Fischer-Mogensen, Nielsen, Hermansen,
& Berntsen, 2013). Together, the various strands of evidence point to the conclusion
that the hippocampus plays a role in the initial encoding of information and serves as
a way station from which information is sent for long-term storage to neural circuits in
the cerebral cortex. The hippocampus is especially involved in our memories of
places, providing us with something of a “cognitive map” (Best, White, & Minai, 2001;
Redish, 1999).
In Aarhus, Denmark, a museum has created a special place called the
reminiscence apartment. All of the rooms are decorated and stocked with items from
the 1950s, similar to this cluttered kitchen from the same era. Only persons with
dementia and Alzheimer’s disease are allowed to tour and interact with the
apartment, as it is used to help them remember, socialize, and improve their mood.
iStock.com/JodiJacobson
Clearly, not all aspects of memory require the hippocampus. As we’ll see later,
amnesics like H.M. do exhibit memory, but in indirect ways. They can be conditioned
to blink to a tone that has been paired with a puff of air to the eye, and they can
remember how to work a maze they have practiced (as illustrated in Figure 6.15)—
but they cannot recall the training sessions. Similarly, they form preferences for new
music they hear but do not recognize the melodies in a test situation. And they retain
their procedural memories of how to read, write, and use other previously learned
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skills. For these types of memory tasks, different structures are involved. For
example, David McCormick and Richard Thompson (1984) located a microscopic
spot in the cerebellum that controls the classical conditioning of the eyeblink reflex.
Certain areas of the brain specialize in certain types of input, but for something as
complex as memory, many areas are needed.
Description
Figure 6.15 The Mirror-Tracing Task
Adapted from Openstax Psychology text by Kathryn Dumper, William
Jenkins, Arlene Lacombe, Marilyn Lovett and Marion Perlmutter licensed
under CC BY v4.0. https://openstax.org/details/books/psychology
The Biochemistry of Memory.
As some researchers try to locate where memories are stored, others seek to
identify the accompanying biochemical changes that take place in the neural circuits.
Most of these changes are likely to be found at the synapses, the tiny gaps between
neurons that are linked together by the release of neurotransmitters.
One neurotransmitter that seems to play an important role in memory is
acetylcholine. (Review Chapter 2 on behavioral neuroscience for more on the
functions of acetylcholine.) Research shows that people with Alzheimer’s disease not
only lose hippocampal density but also have lowered levels of acetylcholine and
fewer acetylcholine receptors in the brain (Oz, Petroianu, & Lorke, 2016). Research
with animal models has demonstrated that activation of acetylcholine receptors
prevents memory impairments and, thus, can be a promising treatment for humans
(Lebois et al., 2017). Currently, Alzheimer’s disease has no cure, but
pharmacotherapies have somewhat improved quality of life and shown moderate
effectiveness (Folch et al., 2016).
Certain hormones are also involved in memory. Glucocorticoids—such as cortisol
—are a group of hormones released during stress (Joëls & Krugers, 2007). Stress, in
turn, can help or hinder memory (Joëls & Krugers, 2007; Schwabe, Joëls,
Roozendaal, Wolf, & Oitzl, 2012). For example, some people perform well under
pressure, while others choke. Researchers propose that when glucocorticoids are
combined with catecholamines—epinephrine, norepinephrine, and dopamine—an
organism can effectively encode new information during stressful events (Schwabe et
al., 2012). Developmental studies argue that early life stress prepares organisms for
better memory performance in stressful conditions later in life, which could also
explain why some people succeed and others fail under pressure (Oitzl, Champagne,
van der Veen, & de Kloet, 2010; Oomen et al., 2010). However, correlational studies
with humans contradict these findings. In studies by Gutteling et al. (2006) and
Laplante et al. (2008), mothers who experienced a natural disaster while pregnant
had offspring who showed cognitive impairment when tested at the ages of 5 to 7
years. As you have probably guessed, many questions about hormones, stress, and
memory remain (Schwabe et al., 2012).
Retrieval
Once information is stored, how do you know it exists? Because people can
openly report their recollections, this seems like a silly question. In fact, however, this
is one of the thorniest questions confronting cognitive psychologists. Hermann
Ebbinghaus (1885/1913) was not only the first person to study memory systematically
but also the first to realize that a memory may exist without awareness. In his words,
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“These experiences remain concealed from consciousness and yet produce an effect
which is significant and which authenticates their previous experience” (p. 2).
Memory without awareness illustrates how human beings can be both competent
and incompetent at the same time, and it poses a profound challenge to the
researcher: If people have memories they cannot report, how can we ever know
these memories exist? To his credit, Ebbinghaus devised a simple but clever
technique. He tested memory by its effect on performance. Acting as his own subject,
he would learn a set of nonsense syllables and then count the number of trials it later
took him to relearn the same list. If it took fewer trials the second time around than
the first, then he must have retained some of the material—even if he could not
consciously recite it.
In recent years, other techniques have been devised. Basically, there are two
types of tests, and each assesses a different type of memory: one explicit, the other
implicit. Explicit memory is a term used to describe the recollections of facts and
events that people try to retrieve in response to direct questions. In contrast, implicit
memory is a term used to describe the retention of information without awareness,
as measured by its indirect effects on performance (Jacoby, Toth, & Yonelinas, 1993;
Roediger, 1990; Schacter, 1992). Why is this distinction important? The reason, as
we’ll see, is that people often exhibit dissociations between the two types of tasks.
That is, people will consciously forget (have no explicit memory of) an experience but
at the same time show the effects (have an implicit memory) of that experience.
There are different ways to interpret this pattern. Some scientists believe that explicit
and implicit memory are separate systems that are controlled by different parts of the
brain (Kandel, Dudai, & Mayford, 2014). On the contrary, others believe that the
dissociations merely indicate differences in the way information is encoded and
retrieved (Belleville, Caza, & Peretz, 2003; Foster & Jelicic, 1999; Perrin, 2018).
Either way, it’s useful to consider these two aspects of memory separately (as
summarized in Table 6.1).
explicit memory. The types of memory elicited through the conscious retrieval of
recollections in response to direct questions.
implicit memory. A nonconscious recollection of a prior experience that is
revealed indirectly, by its effects on performance.
Table 6.1
Explicit Memory
Have you even taken a multiple-choice test? This task, which requires you to
select a remembered item from a list of alternatives, is a recognition test—so are
playing the popular game show Beat Shazam, picking a criminal from a lineup, or
identifying photographs from a family album.
recognition. A form of explicit-memory retrieval in which items are presented to a
person who must determine if they were previously encountered.
Research shows that recall and recognition are both forms of explicit memory in
that people are consciously trying to retrieve the information (Haist, Shimamura, &
Squire, 1992). There is, however, a key difference: People tend to perform better at
recognition. Bahrick and colleagues (1975) reported this difference in a study of longterm memory. They showed people pictures of classmates taken from their high
school yearbooks. Seven years after graduating, subjects were able to correctly recall
only 60 percent of the names belonging to each face. But those who only had to
recognize the right names from a list of possible alternatives were 90 percent
accurate—even when tested 14 years after graduation.
The fact that recognition is easier than recall tells us that forgetting sometimes
occurs not because memory has decayed but because the information is difficult to
reclaim from storage. Retrieval failure is a common experience. Have you ever felt as
though a word or a name you were trying to recall was just out of reach—on the tip of
your tongue? In a classic study of the tip-of-the-tongue phenomenon, Roger Brown
and David McNeill (1966) prompted this experience by giving students definitions of
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uncommon words and asking them to produce the words themselves. For example,
what is “the green-colored matter found in plants”? And what is “the art of speaking in
such a way that the voice seems to come from another place”? Most often, subjects
either knew the word right away or were certain that they did not know it. But at times,
subjects knew they knew the word but could not recall it—a frustrating state that
Brown and McNeill likened to being on the brink of a sneeze.
The experience is an interesting one. When a word is on the tip of the tongue,
subjects often come up with other words that are similar in sound or meaning.
Searching their memory for chlorophyll, subjects might say chlorine or cholesterol.
For ventriloquism, they produce words such as ventilate and vernacular. In fact, a
surprising number of people will guess the correct first letter, last letter, and number
of syllables contained in the missing word. These cases reveal that the information is
in memory but that people need “hints” to dislodge it (Brown, 1991). Thus, while
people in their 70s and 80s have more tip-of-the-tongue experiences than do younger
adults, they too can bring the words to mind when given the right prompting (Heine,
Ober, & Shenaut, 1999). The tip-of-the-tongue experience is common, frustrating,
and effortful, and it tells us something about why stored memories are sometimes
“lost” and how they can be retrieved (Schwartz, 2002).
Recognition is often easier than recall because recognition tasks contain retrieval
cues, or reminders. A retrieval cue is a stimulus that helps us to access information in
long-term memory. According to Tulving’s (1983) principle of encoding specificity,
any stimulus that is encoded along with an experience can later trigger one’s memory
of that experience. For mock jurors, a simple trial-ordered-notebook containing
headings to outline the trial proceedings served as a successful retrieval
enhancement (Thorley, Baxter, & Lorek, 2015). Retrieval cues can be anything from a
picture, a location, a word, or a song, to another person, a fragrance, or the mood
we’re in.
encoding specificity. The principle that any stimulus encoded along with an
experience can later jog one’s memory of that experience.
Context-Dependent Memory.
Tulving’s principle gave rise to the interesting notion that memory is “context
dependent”—that people find it easier to retrieve information from memory when
they’re in the same situation in which the information was obtained in the first place.
In an unusual initial test of this hypothesis, researchers presented scuba divers with a
list of words in one of two settings: 15 feet underwater or on the beach. Then they
tested the divers in the same setting or in the other setting. Illustrating contextdependent memory, the divers recalled 40 percent more words when the material
was learned and retrieved in the same context (Godden & Baddeley, 1975). This is
why the “retrace your steps” method is helpful when you have lost an item. Standing
in the places where you last had the item helps you to remember where you might
have last placed it, since the environmental cues can serve as a prime to activate
information located in your implicit memory. For example, you might haphazardly lay
down your keys when in a hurry and, thus, not pay attention to their placement. When
it comes time to leave, your keys are nowhere to be found until you move through the
space the same way you did when you remembered having them in hand. You see
your backpack, and that acts as a prime. Suddenly, your implicit memory becomes
vivid and you lift your backpack to find the keys underneath.
The premise? To hear as few notes as possible before you are able to name the
tune. Your competition? The Shazam app. The game show Beat Shazam is a test of
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p pp g
recognition memory where notes from a wide range of songs act as retrieval cues.
Think you can beat Shazam? Download the app, then listen to a streaming music
service and test how quickly you can name the tunes. Players on the game show can
win up to $1 million.
FOX / Contributor/FOX Image Collection/Getty Images
Context seems to activate memory even in 3-month-old infants. In a series of
studies, Carolyn Rovee-Collier and colleagues (1992) trained infants to shake an
overhead mobile equipped with colorful blocks and bells by kicking a leg that was
attached to the mobile by a ribbon. The infants were later more likely to recall what
they learned—which they demonstrated by kicking—when tested in the same crib
containing the same visual cues than when there were differences.
Cai and colleagues (2016) believe that a set of findings using animal models
demonstrate the biological reason for contextual retrieval of memories. When
learning occurs, an ensemble of overlapping neurons fire. These neurons are called
CA 1, and they “serve to link and strengthen memories, thus facilitating integrated
recall of experiences encoded close in time while separating those encoded further in
time” (p. 118). With age, the excitability of CA 1 neurons decreases. Thus, a contextdependent fear response in mice happens for those that are younger but not for
those that are older. In an attempt to repair the loss of CA 1 neuron excitability—and,
as a result, reinvigorate context-dependent memory—Cai and colleagues (2016)
injected aged mice with a specialized drug or saline. Aged mice that received the
drug had the same context-dependent fear response as young mice, whereas aged
mice that received the saline did not.
State-Dependent Memory.
Internal cues that become associated with an event may also spark the retrieval of
explicit memories. Illustrating the phenomenon of “state-dependent” memory, studies
reveal that it is often easier to recall something when our state of mind is the same at
testing as it was during encoding. If you have an experience when you are happy or
sad, calm or aroused, that experience—unless your emotional state is intensely
distracting—is more likely to pop to mind or be free-recalled when your internal state
later is the same than when it’s different (Bower, 1981; Kenealy, 1997).
Whether a person is drunk or sober during the experience has yielded mixed
results in state-dependent memory experiments (Compo et al., 2017). Thus, Compo
and colleagues (2017) decided to randomly assign participants to a control, placebo,
or alcohol encoding condition. The memory that participants were tasked to encode
was of a simulated crime. Participants witnessed the simulated crime and, after a
delay, were placed in the same state during retrieval. Intoxicated participants were
less accurate than those in the control and placebo conditions. Intoxicated
participants’ memory performance was best when they were able to immediately
provide information about what they witnessed. In lieu of these findings, Compo and
colleagues (2017) suggest that intoxicated witnesses be interviewed immediately
instead of after a delay—providing time to sober up could harm memory retrieval.
What about state-dependent retrieval that relies on environment? Eric Eich (1995)
has found that the reason it helps to be memory-tested in the same place where you
learned the material is that the environment is likely to transport you back to the same
mood state—and it’s this mood state that serves as a retrieval cue. When it comes to
mood as an internal state and memory, there is a complicating factor: The mood
we’re in often leads us to evoke memories that are congruent with that mood. When
people are happy, the good times are easiest to recall. But when people are sad,
depressed, or anxious, their minds become flooded with negative events of the past.
Currently depressed people thus report having more intrusive memories of death and
other bad experiences, compared to nondepressed control subjects (Brewin,
Reynolds, & Tata, 1999). Furthermore, vocabulary acquisition can be harmed by the
presentation of negative stimuli. Miller and colleagues (2017) discovered that English
speakers who were exposed to negative stimuli while trying to learn a foreign
language had poor recall performance. Their explanation was that negative stimuli
impeded the brain’s ability to connect new words with meaning.
Implicit Memory
In 1911, physician Édouard Claparède described an encounter he had with a
young woman who suffered from Korsakoff syndrome—a brain disorder, common
among those with chronic alcoholism, that impairs the transfer of information into
long-term memory. When Claparède was introduced to the woman, he hid in his right
palm a pin that pricked her painfully as the two shook hands. The next day, he
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returned to the hospital. Due to her memory disorder, the patient did not recognize
the doctor and could not answer questions about their prior interaction. Yet when he
reached out to shake her hand, she pulled back abruptly. Why did she refuse? After
some confusion, all she could say was, “Sometimes pins are hidden in people’s
hands” (Schwartz & Reisberg, 1991).
Implicit Memory in Amnesia Patients.
Did Claparède’s patient remember him or not? On the one hand, she knew
enough to be afraid. On the other hand, she did not know why. It was as if she had a
memory but didn’t know it. As unusual as this story may seem, we now know that
there are many others like it. As in the case of H.M., cognitive psychologists are
keenly interested in people with amnesia. Earlier, researchers believed that amnesics
lacked the ability to encode or store information in long-term memory. They could still
perform “skills”—but could not keep new “information” in memory.
Researchers have demonstrated that people find it easier to remember
information when they are in the same environment where the information was first
learned.
iStock.com/fizkes
Or could they? Elizabeth Warrington and Lawrence Weiskrantz (1970) published
an article in Nature that challenged the prevailing view. These researchers gave a list
of words to 4 amnesics and 16 normal control subjects. Four memory tests were then
administered. Two were standard measures of explicit memory—one a recall task,
the second involving recognition. The other tests were indirect measures of implicit
memory in which the subjects were asked merely to complete word fragments (such
as k---ht, c-l---e, and t---v-s-on) and stems (e.g., kni---, col----, and tele------) with the
first “guess” that came to mind. The results are shown in Figure 6.16. As was
expected, the control subjects scored higher than the amnesics on the explicitmemory tests. But on the incomplete-word tasks, the amnesics were just as likely to
form words that appeared on the original list. Like Claparède’s Korsakoff syndrome
patient, they retained the information enough to use it. They just didn’t realize it.
Description
Figure 6.16 Retention Without Awareness
Source: Warrington, E. K., & Weiskrantz, L. (1970). Amnesic
syndrome: Consolidation or retrieval? Nature, 228(5272), 628–630.
https://doi.org/10.1038/228628a0
Today, many case studies indicate that amnesics know more than they realize.
Consider the case of Clive Wearing, a musicologist, conductor, and pianist whose
central nervous system was attacked by the herpes virus. According to a Radiolab
interview with Clive’s wife and Oliver Sacks, the virus damaged Clive’s hippocampus,
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which resulted in a sense of “waking up”—from what he believed to be an incredibly
long sleep—every 20 seconds (Abumrad & Krulwich, 2007). His diary has the
following statement written in it over and over:
8:31 AM: Now I am really, completely awake.
9:06 AM: Now I am perfectly, overwhelmingly awake.
9:34 AM: Now I am superlatively, actually awake.
When asked who wrote the previous statements that are crossed out, Clive
claimed that the statements were in his handwriting, but he had no idea who put the
statements there.
Can Clive remember anything? Yes, he can. Take his wife, Deborah. When he
sees her, it is like he is seeing Deborah for the first time in years. His face lights up,
he begins to hum a love song, and he grabs Deborah in a romantic embrace. Clive
can also play the piano and direct a choir without complication since his procedural
memory was left intact. As for learning new information, repeated presentation of a
video clip has revealed that Clive can anticipate what will happen next, regardless of
his firm belief that the video is completely novel.
This dissociation—the tendency for amnesics to show signs of long-term retention
of information without awareness—has now been amply observed in studies involving
different types of amnesia and different implicit-memory tests. For example,
researchers tried to classically condition a patient who had anterograde amnesia by
pairing a harmless tone with electric shock. Although the patient could not later recall
these sessions, he reacted with greater arousal whenever the tone was presented
(Bechara, Tranel, Damasio, Adolphs, & Damasio, 1995). This classical conditioning is
likely what led Claparède’s patient to refuse to shake hands. In another study, elderly
patients with Alzheimer’s disease played a weather prediction game on a computer.
They had to guess rain or shine after learning, through trial and error, what clues
signaled the correct prediction. Compared to healthy elderly control subjects, the
Alzheimer’s patients could not later recall the clues, the test, or the layout of the
computer display. But they were accurate in their weather predictions—indicating that
they had an implicit memory of what they had learned, a form of retention without
awareness (Eldridge, Masterman, & Knowlton, 2002).
Implicit Memory in Everyday Life.
You don’t have to suffer from brain damage or drug-induced amnesia to exhibit a
dissociation between memory and awareness. Have you ever had the eerie feeling
that you’ve been in a situation before, even though you had not? This is called déjà
vu, and it is defined as the illusion that a new situation is familiar (the term is French
for “already seen”). In a way, déjà vu is the opposite of amnesia. Whereas amnesics
have memories without awareness or familiarity, the person with déjà vu has a sense
of familiarity but no real memory. Estimates vary, but Psychology Today reports that
between 60 and 70 percent of people report having had such an episode (Lewis,
2012).
Déjà vu is not the only type of dissociation that is commonly experienced.
Retention without awareness occurs in all of us—sometimes with interesting
consequences. Let’s now consider two consequences: eyewitness transference and
unintentional plagiarism:
Eyewitness Transference.
False fame may seem amusing, but retention without awareness can also have
serious consequences. Several years ago, psychologist Donald Thompson was
falsely accused of rape on the basis of the victim’s recollection. Remarkably for
Thompson, he was being interviewed live on television as the rape occurred—an
interview, ironically, on the subject of human memory. Apparently, the victim was
watching Thompson’s show just before being attacked and then mistook him for the
rapist. Was Thompson familiar to her? Yes, he was—but from the TV show, not from
the crime scene. Thanks to his airtight alibi, Thompson was vindicated instantly.
Perhaps others have not been so fortunate.
The problem illustrated by this story is that sometimes witnesses remember a face
but forget the circumstances in which they saw it. In one study, subjects witnessed a
staged crime and then looked through mug shots (Brown, Deffenbacher, & Sturgill,
1977). A few days later, they were asked to view a lineup. The result was startling:
Subjects were as likely to identify an innocent person whose photograph was in the
mug shots as they were to pick the actual criminal. This familiarity effect gives rise to
the phenomenon of eyewitness transference, whereby a person seen in one situation
is later confused in memory, or “transferred,” to another situation—often with tragic
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consequences (Dysart, Lindsay, Hammond, & Dupuis, 2001; Ross, Ceci, Dunning, &
Toglia, 1994; Steblay & Dysart, 2016).
Unintentional Plagiarism.
False fame and unconscious transference occur when we are aware that
something is familiar but we cannot pinpoint the correct source of that familiarity
(Johnson, Hashtroudi, & Lindsay, 1993; Mandler, 1980). In other words, the
experience has an impact on behavior but without our conscious awareness. There is
another possible repercussion of implicit memory: unintentional plagiarism.
Unintentional plagiarism happens in music quite frequently. The song “My Sweet
Lord” by former Beatles member George Harrison is almost identical to the song
“He’s So Fine” by the Chiffons. The latter song’s author, Ronnie Mack, filed a lawsuit
in 1971. Harrison was taken to court and found guilty of subconscious plagiarism,
what we call unintentional plagiarism. This resulted in a $1,599,987 fine that was then
reduced to $587,000 after Harrison’s manager purchased the rights to “He’s So Fine.”
The legal battle did not end officially until 1998, but it set a precedent for stricter
copyright standards in the music industry (Runtagh, 2016). Musicians such as Robin
Thicke, Pharrell Williams, Justin Bieber, Madonna, Lana Del Ray, and Ed Sheeran
have all been sued for plagiarism in recent years.
Figure 6.17 Inspiration and Plagiarism
Kevin Mazur / Contributor/WireImage/Getty Images; Afro
Newspaper/Gado / Contributor/Archive Photos/Getty Images
Have you ever had an insight you thought was original, only to realize or be told
later that it was “borrowed” from another source? Are people who write, compose
music, solve problems, tell jokes, or think up creative ideas vulnerable to
unintentional plagiarism? Alan Brown and Dana Murphy (1989) had subjects in
groups take turns generating items that fit a particular category (sports, four-legged
animals, musical instruments, and clothing). After four rounds, they asked subjects
individually to recall the items that they personally had generated and to come up
with new ones from the same categories. As it turned out, 75 percent of the subjects
took credit for at least one item of someone else’s, and 71 percent came up with a
“new” item that was given earlier. Some subjects inadvertently plagiarized their own
ideas, but most often they “stole” from others in the group.
Additional research has shown that people are vulnerable to unintentional
plagiarism in some situations more than others. Predictably, the problem is more
likely to occur when the ideas taken are highly memorable; when the person who
gave the original ideas has status; when the original ideas were shared in
anonymous group situations; when subjects were distracted, in a hurry, or not overly
concerned about the origin of their ideas; and after a long period of time has elapsed
(Macrae, Bodenhausen, & Calvini, 1999; Marsh & Bower, 1993; Marsh, Landau, &
Hicks, 1997; Tenpenny, Keriazakos, Lew-Gavin, & Phelan, 1998). As in other
research on implicit memory, these studies show that there is a bit of amnesia in all of
us. Commenting on the amount of unconscious plagiarism exhibited by research
participants in his laboratory, Richard Marsh speculates that the problem is “a heck of
a lot more common than anybody would realize” (Carpenter, 2002). One strategy to
help avoid unintentional plagiarism is to keep track of ideas gathered from sources as
you work. The free software Zotero and Evernote can assist with this. If you try to
connect the sources with the ideas after the work is done, you risk forgetting which
source goes with what idea, or if there was even a source at all. This is what
happened to Harvard journalism lecturer, writer, and former New York Times
executive editor Jill Abramson. Abramson’s work Merchants of Truth reportedly
plagiarized several different sources (Malooley, 2019). One of her plagiarized
sources, Jake Malooley, interviewed her about why she plagiarized his work.
Abramson admitted to not keeping track of citations and sources, stating simply, “I
mistook it for mine” (Malooley, 2019). In other words, Abramson thought Malooley’s
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