Have you ever heard the saying “an elephant never forgets?” Granted, this might be somewhat of an overstatement, but as far as animals go, elephants do have remarkable memories. Consider the story of two elephants that briefly worked together in the circus and then were separated for 23 years. When they reencountered one another at an elephant sanctuary in Tennessee, the two animals started to inspect each other’s trunk scars and “bellowed” in excitement: The long-lost friends had recognized one another (Ritchie, 2009, January 12)! An elephant’s memory—and yours, too—is only as good as its ability to retrieve stored memories. Let’s return to the World Memory Championships and examine the critical process of retrieval.

LO 9 Illustrate how encoding specificity relates to retrieval cues.

Every event in the World Memory Championships begins with encoding data into the memory system and storing that information for later use. Contestants are presented with information—numbers, words, historic dates, and the like—and provided a certain amount of time to file it away in long-term memory. But no matter how much information they absorb, the contestants’ efforts are meaningless if they can’t retrieve it in the recall phase of the event.

RETRIEVAL CUES AND PRIMING One of the most grueling events in the World Memory Championships is “One Hour Numbers,” a race to see who can memorize the greatest number of random digits in an hour. Contestants are given four sheets of paper, each containing 1,000 random digits, and 1 hour to cram as many as possible into their long-term memories. During the recall phase that follows, they get 2 hours to scrawl the correctly ordered numbers on blank sheets of paper. This is a backbreaker because there are no reminders, or retrieval cues, to help contestants locate the information in their long-term memory. Retrieval cues are stimuli that help you retrieve stored information that is difficult to access (Tulving & Osler, 1968). For example, let’s say you were trying to remember the name of the researcher who created the working memory model introduced earlier in the chapter. If we gave you the first letter of his last name, B, would that help you retrieve the information? If your mind jumped to “Baddeley” (the correct answer), then B served as your retrieval cue.

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Even Clive Wearing, who could not remember what was happening from one moment to the next, showed evidence of using retrieval cues. For instance, Clive spent 7 years of his life at St. Mary’s Hospital in Paddington, England, yet had no conscious memory of living there. And, according to his wife Deborah, Clive was “completely devoid” of knowledge of his own location; the hospital name was not at all connected with his sense of location (D. Wearing, personal communication, June 25, 2013). But if Deborah prompted him with the words “St. Mary’s,” he would chime back, “Paddington,” oblivious to its connection (Wearing, 2005, p. 188). In this instance, the retrieval cue in Clive’s environment (the sound of the word “St. Mary’s”) was priming his memory of the hospital name. Priming is the process of awakening memories with the help of retrieval cues.

At this point, you may be wondering how priming can occur in a person with severe amnesia. Clive’s conscious, explicit memory is diminished, but his unconscious, implicit memory still functions. Just because he could not articulate, or “declare,” the name of the hospital does not mean that the previously known word combination had entirely vanished from his memory system.

RECALL AND RECOGNITION Now let’s return to the “One Hour Numbers” event of the World Memory Championships. This type of challenge relies on pure recall, the process of retrieving information held in long-term memory without the help of explicit retrieval cues. Recall is what you depend on when you answer fill-in-the-blank or short-answer essay questions on exams. Say you are given the following prompt: “Using a computer metaphor, what are the three processes involved in memory?” In this situation, you must come up with the answer from scratch: “The three processes are encoding, storage, and retrieval.”

Now let’s say you are faced with a multiple-choice question: “One proven way of retaining information is: (a) distributed practice, (b) massed practice, or (c) eidetic imagery.” Answering this question relies on recognition, the process of matching incoming data to information stored in long-term memory. Recognition is generally a lot easier than recall because the information is right before your eyes; you just have to identify it (Hey, I’ve seen that before). Recall, on the other hand, requires you to come up with information on your own. Most of us find it easier to recognize the correct answer from a list of possible answers in a multiple-choice question than to recall the same correct answer for a fill-in-the-blank question.

SERIAL POSITION EFFECT Recall and recognition come into play outside of school as well. Just think about the last time someone asked you to pick up some items at the store. In order to find the requested goods, you had to recognize them (There’s the ketchup), but even before that you had to recall them—a much harder task. The ability to recall items from a list depends on where they fall in the list, a phenomenon psychologists call the serial position effect (Figure 6.8). When given a list of words to memorize, research participants are better able to remember items at the beginning of the list, which is known as the primacy effect, as well as items at the end, which is called the recency effect (Deese & Kaufman, 1957; Murdock, 1962).

Imagine you are on your way to the store to buy supplies for a dinner party, but your cell phone battery is about to die. Your phone rings; it’s your housemate asking you to pick up the following items: napkins, paper towels, dish soap, butter, laundry soap, paper plates, sparkling water, ice cream, plastic spoons, bread, pickles, and flowers. Without any way to write down this list, you are at the mercy of the serial position effect. In all likelihood (and if you don’t use mnemonics), you will return home with napkins, paper towels, and a bottle of dish soap (due to the primacy effect), as well as bread, pickles, and flowers (due to the recency effect); the items in the middle will more likely be forgotten.

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When it comes to retrieving memories, context matters. Where were you when you encoded the information, and what was occurring around you? Researchers have found that environmental factors play a key role in determining how easily memories are retrieved.

CONTEXT IS EVERYTHING In a classic study by Godden and Baddeley (1975), participants learned lists of words under two conditions: while underwater (using scuba gear) and on dry land. They were then tested for recall in both conditions: If they learned the list underwater, they were tested underwater and on dry ground; if they learned the list on dry ground, they were tested on dry ground and underwater. The participants were better able to retrieve words when the learning and recall occurred in the same location (Figure 6.9). If they learned the words underwater, they had an easier time recalling them underwater. Words learned on land were easier to recall on land. Here we have an example of context-dependent memory; memories are easier to access when the encoding and retrieval occur in similar contexts.

Context-dependent memory is part of a broader phenomenon conveyed by the encoding specificity principle, which states that memories are more easily recalled when the context and cues at the time of encoding are similar to those at the time of retrieval (Smith, Glenberg, & Bjork, 1978; Tulving & Thompson, 1973). There is even evidence that summoning a memory for an event reactivates the same brain areas that became excited during the event itself (Danker & Anderson, 2010). This suggests that the activity in your brain at the time of encoding is similar to that at retrieval, and researchers using fMRIs have found support for this (Gottfried, Smith, Rugg, & Dolan, 2004).

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IT ALL COMES FLOODING BACK In your own life, you may have noticed that old memories tend to emerge from the woodwork when you return to the places where they were created. Dining at a restaurant you once frequented with an ex-boyfriend or girlfriend probably sparks memories of romantic moments (or perhaps a bitter argument) you had there. Going to a high school reunion might bring back memories of football games, dances, and classrooms not recalled in years. How does returning to the birthplace of a memory help bring it to mind? Places where memories are created often abound with retrieval cues—sights, sounds, tastes, smells, and feelings present at the time of encoding. These retrieval cues help awaken stored memories.

Suppose you go to a friend’s house to watch the James Bond movie Skyfall. While encoding a memory of the movie, you are exposed to all sorts of stimuli in the environment, such as the hum of an air conditioner, the taste of the chips and salsa you are munching on, the tabby cat purring next to you on the sofa. All these feelings have nothing to do with Skyfall, but they are strongly linked to your experience of watching the film. So the next time you are at your friend’s house and you see that tabby cat purring on a sofa, thoughts of 007 might come back to you.

MOODS, INTERNAL STATES, AND MEMORY The encoding specificity principle does not merely apply to the context of the surroundings. Remembering things is also easier when physiological and psychological conditions, including moods and emotions, are similar at the time of encoding and retrieval. Sometimes memories can be best retrieved under such circumstances; we call this state-dependent memory. One morning upon awakening, you spot a red cardinal on your window ledge. You forget about the cardinal for the rest of the day—even when you pass the very same window. But come tomorrow morning when you are once again half-awake and groggy, memories of the red bird return. Here, your ability to recall the cardinal is dependent on your internal or physiological state being the same as it was at the time of encoding. Retrieval is also easier when the content of a memory corresponds to our present emotional state, a phenomenon known as mood congruence (Bower, Gilligan, & Menteiro, 1981; Drace, Ric, & Desrichard, 2010). If you are in a happy mood, you are more likely to recollect a happy-go-lucky character from a book, but if you are in a sour mood, you are more inclined to remember the character whose bad mood matches yours.

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Retrieval is clearly at work in recall and recognition, the two processes we compared above. But there is another, less obvious form of retrieval that occurs in the process of relearning. Perhaps you’ve noticed that you learn material much more quickly a second time around. Math equations, vocabulary, and grammar rules seem to make more sense when you’ve seen them before. Some information seems to stick better when we learn it twice (Storm, Bjork, & Bjork, 2008).

HERMANN EBBINGHAUS The first person to quantify the effect of relearning was Hermann Ebbinghaus (1850 –1909), a German psychologist and pioneering researcher of human memory. Ebbinghaus was the sole participant in his experiments, so his research actually shed light on his memory, although the trends he uncovered in himself seem to apply to human memory in general.

Thorough scientist that he was, Ebbinghaus spent hour upon hour, day after day memorizing lists of “nonsense syllables”—meaningless combinations of vowels and consonants such as DAZ and MIB. Once Ebbinghaus had successfully remembered a list, meaning he could recite it smoothly and confidently, he would put it aside. Later, he would memorize it all over again and calculate how much time he had saved in Round 2, a measure called the “savings score” (Ebbinghaus, 1885/1913). In a study that supports Ebbinghaus’ theory of savings in relearning, participants who were asked to memorize number–word pairs (for example, 17-snake, 23-crown) showed significant savings in the amount of time needed to relearn the number–word pairs 6 weeks later (Marmurek & Grant, 1990).

Since no one spends all day memorizing nonsense syllables, you may wonder how Ebbinghaus’ research and the “savings score” apply to real life. At some point in school, you probably had to memorize a famous speech like Dr. Martin Luther King’s “I Have a Dream.” Let’s say it took you 100 practice sessions to recite the speech flawlessly. Then, a month later, you tried memorizing it again and it only took 50 attempts. Because you cut your learning time in half (from 100 practice sessions to 50), your savings score would be 50%.

A FOREIGN LANGUAGE? Learning is a lot like blazing a trail through freshly fallen snow. Your first attempt plowing through the powder is hard work and slow going, but the second time (relearning) is easier and faster because the snow is packed and the tracks already laid down. This also seems to be true for relearning a forgotten childhood language. One small study focused on native English speakers who as children had been exposed to either Hindi or Zulu to varying degrees. Although none of the adults in the study had any explicit memories of those languages, those who were under 40 were still able to distinguish sounds from their childhood languages better than members of a control group with no exposure to these languages (Bowers, Mattys, & Gage, 2009). The implication is that people who have some knowledge of a language (even if they don’t realize it) benefit from this memory, by showing a “memory savings” if they try to learn the language again. They are a step ahead of other adults learning that language for the first time.

LO 10 Identify some of the reasons why we forget.

Once Dorothea has memorized numbers, images, and other bits of information for the World Memory Championships, how long do they stick in her mind—an hour, a day, a week? Dorothea reports that images and words can last for several days, but meaningless strings of numbers, like the hundreds of digits memorized for the “One Hour Numbers” event, tend to fade within a day.

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This would probably come as no surprise to Hermann Ebbinghaus, who, in addition to demonstrating the effects of relearning, was the first to illustrate just how rapidly memories vanish. Through his experiments with nonsense syllables, Ebbinghaus (1885/1913) found that the bulk of forgetting occurs immediately after learning. If you look at his curve of forgetting (Figure 6.10), you will see his memory of word lists plunging downward the hour following learning, then leveling off thereafter. Think about how the curve of forgetting applies to you. Some of what you hear in a psychology lecture will disappear from memory as soon as you walk out the door, but what you remember a week later will probably not differ much from what you recall in a month.

ENCODING FAILURE What exactly causes us to forget? That may depend on the stage of memory processing—encoding, storage, or retrieval—at which a given instance of memory failure occurs. Sometimes details and events we think we have forgotten were actually never encoded in the first place. Take this example: After a long and stressful day, you stop at the supermarket to pick up a frozen dinner. While fumbling through your bag in search of your wallet, you take out your gloves and place them on the cashier’s counter, but because your attention is focused on finding your wallet, you don’t even notice where you’ve placed the gloves. Then you pay and walk out the door, only to wake up the next morning wondering where you left your gloves! This is an example of encoding failure because the data never entered your memory system. You never registered putting your gloves on the counter in the first place, so how can you expect to remember where you left them? For a classic demonstration of encoding failure, take a look at the 10 pennies appearing in the Try This. You’ve looked at a penny hundreds of times in your life, so identifying the real penny should be no problem, right?

try this
Look at the 10 pennies to the right.
Which one is correct?
f

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If you’re like most people, chances are you picked the wrong coin because you have never taken the time to study a penny and encode its visual details (Nickerson & Adams, 1979).

STORAGE FAILURE AND MEMORY DECAY Memory lapses can also result from storage failure. Take a moment and try to remember your high school locker combination. At one point you knew these numbers by heart, but they have slipped your mind because you no longer use them. Many memories decay over time, but there is plenty of evidence that we can store a vast fund of information, sometimes for very long periods. Such memories might include the name of the street where you grew up (Schmidt et al., 2000), grades in college (Bahrick, Hall, & Da Costa, 2008), and factual knowledge from college courses (Conway, Cohen, & Stanhope, 1991). However, these types of memories are subject to a variety of inaccuracies and distortions, and tapping into them is not always easy.

TIP-OF-THE-TONGUE PHENOMENON Sometimes we know that we have knowledge of something but just can’t pull it out of storage, or retrieve it. The name of that college classmate or that new blockbuster movie, it’s just sitting on the tip of your tongue but it won’t slide off! This simple retrieval failure is called the tip-of-the-tongue phenomenon. Most of us have this feeling about once a week, but luckily we are able to retrieve the elusive phrase approximately 50% of the time (James & Burke, 2000; Schwartz, 2012). Often we can correctly guess the first letter of the word or how many syllables it has (Hanley & Chapman, 2008). Studies suggest that the tip-of-the-tongue phenomenon becomes more common with age (Brown & Nix, 1996).

HYPERTHYMESTIC SYNDROME What would happen if you had the opposite problem—that is, instead of forgetting all the time, you remembered everything? Imagine how overwhelming it would be to remember all the experiences you have had, all the people you have met, all the meals that you have eaten over the years, and so on. The ability to forget seems to have great adaptive value, because forgetting allows you to attend to what’s going on in the here and now. Some people, however, cannot forget. This type of memory ability is known as hyperthymestic syndrome (Parker, Cahill, & McGaugh, 2006). The irony is that having this type of “super” memory has drawbacks, including problems with abstract thinking and the ability to make generalizations, although it doesn’t necessarily impair day-to-day functioning.

PROACTIVE INTERFERENCE You now know that forgetting can stem from problems in encoding and storage. And the tip-of-the-tongue phenomenon tells us that it can also result from glitches in retrieval. Studies also show that retrieval is influenced, or in some cases blocked, by information we learn before and after a memory is made, which we refer to as interference (Waugh & Norman, 1965). If you have studied more than one foreign language, you have probably experienced interference. Suppose you take Spanish in middle school, and then begin studying Italian in college. As you try to learn Italian, you may find Spanish words creeping into your mind and confusing you; this is an example of proactive interference, the tendency for information learned in the past to interfere with the retrieval of new material. People who learn to play a second musical instrument experience the same problem; the fingering of the old instrument interferes with the retrieval of new fingering.

RETROACTIVE INTERFERENCE Now let’s say you are going on a trip to Mexico and need to use the Spanish you learned back in middle school. As you approach a vendor in an outdoor market in Costa Maya, you may become frustrated when the only words that come to mind are ciao bello and buongiorno (Italian for “hello handsome” and “good day”), when you really are searching for phrases with the same meaning in Español. Here, recently learned information interferes with the retrieval of things learned in the past. We call this retroactive interference. This type of interference can also impact the musician; when she switches back to her original instrument, the fingering techniques she uses to play the new instrument interfere with her old techniques. Thus, proactive interference results from knowledge acquired in the past and retroactive interference is caused by information learned recently (Figure 6.11).

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Although our memories fail us all the time, we manage to get by with a little help from our friends, who remind us to set our alarm clocks, study for tests, and say “happy birthday” to so and so. We have cell phones to store phone numbers and e-mail accounts to maintain addresses. The news media remind us what day it is. And then of course, there is Google.

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Why do we need computers to help us keep track of the loads of information flooding our brains throughout the day? The answer is simple. We can’t remember everything. We forget, and we forget often. Sometimes it’s obvious an error has occurred (I can’t remember where I left my cell phone), but other times it’s less apparent. Have you noticed that when you recall a shared event, your version is not always consistent with those of other people? As you will soon discover, memories are not reliable records of reality. They are malleable (that is, capable of being changed or reshaped by various influences) and constantly updated and revised, like a wiki. Let’s see how this occurs.

LO 11 Explain how the malleability of memory influences the recall of events.

Elizabeth Loftus, a renowned psychologist and law professor, has been studying memory and its reliability for the last 4 decades. During the course of her career, she has been an expert witness in over 200 trials. The main focus of her work is the very problem we just touched upon: If two people have different memories of an event, whom do we believe?

MEMORY RECONSTRUCTED Loftus suggests that we should not expect our accounts of the past to be identical to those of other people or even of our own previous renditions of events. According to Loftus, episodic memories are not exact duplicates of past events (recent or distant). Instead, she and others propose a reconstructionist model of memory “in which memories are understood as creative blendings of fact and fiction” (Loftus & Ketcham, 1994, p. 5). Over the course of time, memories can fade, and because they are permeable, they become more vulnerable to the invasion of new information. In other words, your memory of some event might include revisions to what really happened, based on knowledge, opinions, and information you have acquired since the event occurred.

Suppose you watch a debate between two presidential candidates on live television. A few days later, you see that same debate parodied on Saturday Night Live. Then a few weeks later, you try to remember the details of the actual debate—the topics discussed, the phrases used by the candidates, the clothes they wore. In your effort to recall the real event, you may very well incorporate some elements of the Saturday Night Live skit (for example, words or expressions used by the candidates). The memories we make are not precise depictions of reality, but representations of the world as we perceive it. With the passage of time, we lose bits and pieces of a memory, and unknowingly we replace them with new information.

THE MISINFORMATION EFFECT If you witnessed a car accident, how accurately would you remember it? Elizabeth Loftus and John Palmer (1974) tested the reliability of people’s memories for such an event in a classic experiment. After showing participants a short film clip of a multiple-car accident, Loftus and Palmer quizzed them about what they had seen. They asked some participants, “About how fast were the cars going when they smashed into each other?” Replacing the word “smashed” with “hit,” they asked others, “About how fast were the cars going when they hit each other?” Can you guess which version resulted in the highest estimates of speed? If you guessed “smashed,” you are correct.

One week later, the researchers asked the participants to recall the details of the accident, including whether they had seen any broken glass in the film. Although no broken glass appears in the film, the researchers nevertheless predicted there would be some “yes” answers from participants who had initially been asked about the speed of the cars that “smashed” into each other. Their predictions were correct. Participants who had heard the word “smashed” apparently incorporated a faster speed in their memories, and were more likely to report having seen broken glass. Participants who had not heard the word “smashed” seemed to have a more accurate memory of the filmed car collision. The researchers concluded that memories can change in response to new information, and specifically that the participants’ recollections were altered by the wording of a questionnaire (Loftus & Palmer, 1974). This research suggests that eyewitness accounts of accidents, crimes, and other important events might be altered by factors that come into play after the event occurs. Because memories are malleable, the wording of questions can change the way events are recalled, and care must be taken when questioning people about the past, whether it’s in a therapist’s office, a social service agency, or a police station.

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Researchers have since conducted numerous studies on the misinformation effect, or the tendency for new and misleading information to distort one’s memory of an incident. Studies with a variety of participants have resulted in their “remembering” a stop sign that was really a yield sign, a screwdriver that was really a hammer, and a barn that did not actually exist (Loftus, 2005).

Prosecutors often tell people who have witnessed crimes not to speak to each other, and with good reason. Suppose two people witnessed an elderly woman being robbed. One eyewitness remembers seeing a bearded man wearing a blue jacket swiping the woman’s purse. The other noticed the blue jacket but not the beard. If, however, the two eyewitnesses exchange stories of what they saw, the second eyewitness may unknowingly incorporate the beard into his “memory.” Information learned after the event (that is, the “fact” that the thief had a beard) can unknowingly get mixed in with memories of that event (Loftus, 2005; Loftus, Miller, & Burns, 1978). If we can instill this type of “false” information into a “true” memory, do you suppose it is possible to give people memories for events that never happened? Indeed, it is.

LO 12 Define rich false memory.

Elizabeth Loftus knows firsthand what it is like to have a memory implanted. Tragically, her mother drowned when she was 14 years old. For 30 years, she believed that someone else had found her mother’s body in a swimming pool. But then her uncle, in the middle of his 90th birthday party, told her that she, Elizabeth, had found her mother’s body. Loftus initially denied any memory of this horrifying experience, but as the days passed, she began to “recall” the event, including images of the pool, her mother’s body, and numerous police cars arriving at the scene. These images continued to build for several days, until she received a phone call from her brother informing her that her uncle had been wrong, and that all her other relatives agreed Elizabeth was not the one who found her mother. According to Loftus, “All it took was a suggestion, casually planted” (Loftus & Ketcham, 1994, p. 40), and she was able to create a memory of an event she never witnessed. Following this experience, Loftus began to study rich false memories, that is, “wholly false memories” characterized by “the subjective feeling that one is experiencing a genuine recollection, replete with sensory details, and even expressed with confidence and emotion, even though the event never happened” (Loftus & Bernstein, 2005, p. 101).

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Would you believe that about 25% of participants in rich false memory studies are able to “remember” an event that never happened? Using the “lost in the mall” technique, Loftus and Pickrell (1995) showed just how these imaginary memories take form. The researchers recruited a pair of family members (for example, parent–child or sibling–sibling) and then told them they would be participating in a study on memory. With the help of one of the members of the pair (the “relative”), the researchers recorded three true events from the pair’s shared past and created a plausible story of a trip to a shopping mall that never happened. Then they asked the true “participant” to recall as many details as possible about each of the four events (remember, only three of the events were real), which were presented in a book provided by the researchers. If the participant could not remember any details from an event, he was instructed to write, “I do not remember this.” In the “lost in the mall” story, the participant was told that he had been separated from the family in a shopping mall around the age of 5. According to the story, the participant began to cry, but was eventually helped by an elderly woman and was reunited with his family. Mind you, the “lost in the mall” episode was pure fiction, but it was made to seem real through the help of the participant’s relative (who was working with the researchers). Following a series of interviews, the researchers concluded that 29% of the participants were able to “recall” either part or all of the fabricated “lost in the mall” experience (Loftus & Pickrell, 1995). These findings may seem shocking (they certainly caused a great uproar in the field), but keep in mind that a large majority of the participants did not “remember” the fabricated event (Hyman, Husband, & Billings, 1995; Loftus & Pickrell, 1995).

CONTROVERSIES

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The main message of this section is that memory is malleable, or changeable. What are the implications for eyewitness accounts, especially those provided by children? If we are aware of how questions are structured and understand rewards and punishments from the perspective of a child, then the interview will produce fewer inaccuracies (Sparling, Wilder, Kondash, Boyle, & Compton, 2011). Researchers have found that having children close their eyes increases the accuracy of the testimony (Vredeveldt, Baddeley, & Hitch, 2013, February), but relying solely on their accounts has contributed to many cases of mistaken identity. In addition, the presence of someone in a uniform appears to put added pressure on child eyewitnesses, resulting in more guessing and inaccurate recall (Lowenstein, Blank, & Sauer, 2010).

Before you read on, take a minute and allow the words of Elizabeth Loftus to sink in: “Think of your mind as a bowl filled with clear water. Now imagine each memory as a teaspoon of milk stirred into the water. Every adult mind holds thousands of these murky memories. . . . Who among us would dare to disentangle the water from the milk?” (Loftus & Ketcham, 1994, pp. 3–4). What is the basis for all this murkiness? Time to explore the biological roots of memory.

Question 1

1. The encoding specificity principle

2. Retroactive interference

3. Proactive interference

4. The curve of forgetting

Question 2

1. encoding specificity principle.

2. curve of forgetting.

3. recency effect.

4. serial position effect.

Question 3

1. curve of forgetting.

2. state-dependent memory.

3. savings score.

4. rich false memory.

Question 4