CHAPTER 6 Long-Term Memory: Structure in class as you were learning these facts, you are having an episodic memory, and if you remember the facts about the House and Senate, you are having a semantic memory.Many years later, in college, you probably still know the difference between the Senate and the House of Representatives (your semantic memory is still present), but it is unlikely that you remember what was happening on the speci c day you were sitting in class in the sixth grade learning about the U.S. government (your episodic memory for that event has been lost). As this example illustrates, the knowledge that makes up semantic memories is initially attained through a personal experience that could be the basis of an episodic memory, but memory for this experience often fades, leaving only semantic memory.Another example of “morphing” from episodic plus semantic to only semantic memory is provided by important personal experiences such as graduating from high school. This is an important event in many people’s lives, and one that they may remem-ber for many years. It is likely that many readers of this book can clearly place them-selves at their high school graduation and so still have episodic memories for this event. However, memory for many of the details of this event may fade over the years, until many years later, not enough of the details remain to achieve the mental time travel required for episodic memory (as in the case of your author, who graduated from high school earlier in the last century!). Nonetheless, semantic memory remains if people know the year they graduated, the high school they graduated from, and other factsassociated with their graduation.Semantic Memory Can Be Enhanced If Associated With Episodic Memory Another connection between semantic and episodic memories is that semantic memories that have personal signi cance are easier to remember than semantic memories that are not personally signi cant. For example, knowledge about the facts associated with your high school graduation would be personally signi cant semantic memories because your high school graduation has personal signi cance for you. Robyn Westmacott and Morris Moscovitch (2003) showed that participants have better recall for names of public gures, such as actors, singers, and politicians, whom they associate with per-sonal experiences. For example, you would be more likely to recall the name of a popular singer in a memory test if you had attended one of his or her concerts than if you had just read about the singer in magazines.Semantic Memory Can In uence Our Experience by In uencing Attention Consider this situation: Steven and Troy are watching a football game. The quarterback takes the snap, is rushed hard, and ips the ball over the oncom-ing linemen for a completion. Later, Troy remembers the details of the play, which was a pass over the left side, but the play doesn’t stand out for Steven. Troy remembers the play because his semantic memory, which contains a large amount of knowledge about football, caused him to direct his attention to what various players were doing as the play unfolded. Thus, Troy’s detailed semantic memory about the various types of plays in football helped direct his attention, and he formed memories about speci c plays. In contrast, Steven observed the game differently because of his sparse knowledge of football, so he just remembers that there were running plays and passing plays (● Figure 6.9).The research on chess experts described in Chapter 5 (see page 127) also illustrates how semantic memory can in uence how people allocate their attention. Remember that the experts had better memory for the positions of chess pieces because of their ability to group pieces together in chunks based on the experts’ semantic memory for the ● FIGURE 6.9 A person’s knowledge can inﬂ uence episodic memory. Even though two people have seen the same football game, they remember diﬀ erent things about it because of their diﬀ ering knowledge of football.I remembera football game.I remember the passover the left side on thirdand 10!Low knowledge of footballThey both saw the same game!High knowledge of footballSemantic knowledge can influence formation of episodic memory33559_06_ch06_p146-169.indd 16033559_06_ch06_p146-169.indd 160 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Priming, Procedural Memory, and Conditioning (Implicit)
161positions of chess pieces in other games. The experts’ attention would therefore be directed toward identifying these groups. The nonexperts, who did not have this knowl-edge, were likely to focus their attention differently, looking at the chess pieces indi-vidually rather than as groups.Priming, Procedural Memory, and Conditioning (Implicit)When we access explicit memory, we are conscious of doing so. We know we are think-ing back to relive an earlier experience (episodic memory—Tulving’s “self-knowing” or “remembering”) or that we are retrieving knowledge about past events or about facts we have learned (semantic memory—Tulving’s “knowing”). The de ning characteristic of implicit memory, in contrast, is that we are not conscious we are using it (see the right side of Figure 6.6). Implicit memory occurs when some previous experience in u-ences our performance on a task, even though we do not consciously remember the previous experience. We may not even be aware of exactly how we are accomplishing a particular task. We just do it! (Roediger, 1990; Schacter, 1987; Tulving, 1985). Tulving describes implicit memory as nonknowing.PRIMINGPriming occurs when the presentation of one stimulus (the priming stimulus) changes the response to a subsequent test stimulus (the test stimulus), either positively (positive priming, which causes an increase in speed or accuracy of the response to the test stimu-lus) or negatively (negative priming, which causes a decrease in the speed or accuracy of response to the test stimulus). We will focus on positive priming because most research has studied this type of priming.One type of positive priming, repetition priming, occurs when the test stimulus is the same as or resembles the priming stimulus. For example, seeing the word birdmay cause you to respond more quickly to another presentation of the word bird than to a word you had not seen, even though you may not remember seeing bird earlier. Conceptual priming occurs when the enhancement caused by the priming stimulus is based on the meaning of the stimulus. For example, presentation of the word furniture might cause you to respond faster to a later presentation of the word chair.Repetition priming and conceptual priming are both considered to be implicit mem-ory because their effects can occur even though participants may not remember the orig-inal presentation of the priming stimulus when they are responding to the test stimulus.You may wonder how we can be sure that a person isn’t remembering the priming stimulus when responding to the test stimulus. After all, if we present the word bird, and then later measure how fast a person reacts to another presentation of the word bird, couldn’t that happen because the person remembers the rst time bird was pre-sented? If the person did remember the initial presentation of bird, then this would be an example of explicit memory, not implicit memory. Researchers have used a number of methods to reduce the chances that a person in a priming experiment will remember the original presentation of the priming stimulus.METHOD Avoiding Explicit Remembering in a Priming ExperimentOne way to minimize the chances that a person will remember the presentation of the priming stimulus is to present the priming stimulus in a task that does not appear to be a memory task. For example, if the priming stimuli are the names of animals, participants could be presented with the names and asked to indicate whether the animals would stand more than 2 feet high.In addition to disguising the purpose of the priming stimulus, researchers have devised tests that do not directly test memory. An example of such a test is the word completion Implicit Learning33559_06_ch06_p146-169.indd 16133559_06_ch06_p146-169.indd 161 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 6 Long-Term Memory: Structure task, in which the participant’s task is to create a word from a fragment. For example, the priming stimulus could be the word parrot, and the test stimulus could be the fragment par. The participant’s task is to add letters to create a word. If repetition priming occurs, the par-ticipant will be more likely to complete the fragment to form the priming stimulus then he or she would be if the stimulus had not been presented earlier. In this example, creating the word parrot, rather than other possibilities such as parent or party, would illustrate an e ect of priming.Another example of a test used in repetition priming experiments involves measuring how accurately or quickly the participant responds to a stimulus. For example, participants could be tested by presenting a list of words and asking them to press a key every time they see a word that has four letters. Priming would be indicated by faster or more accurate responding to four-letter words that corresponded to priming stimuli that had been presented earlier. The key characteristic of this test is speed. Requiring a rapid response decreases the chances that the participant will take the time to consciously recollect whether or not they have previously seen the word.Many experiments have been done in which researchers have demonstrated implicit memory using techniques like the ones described above (Roediger, 1990). But the de -nite proof that priming involves implicit memory is provided by neuropsychology experiments on people with amnesia like Jimmy G., whom we described at the begin-ning of the chapter, who cannot remember events that have just happened to them.An example is provided by an experiment by Peter Graf and coworkers (1985), who tested three groups of participants: (1) eight amnesia patients with Korsakoff’s syndrome and two patients with another form of amnesia; (2) patients without amnesia who were under treatment for alcoholism; and (3) patients without amnesia who had no history of alcoholism.Graf and coworkers presented lists of words to their participants and asked them to rate each word on a scale of 1 to 5 based on how much they liked each word (1 = like extremely; 5 = dislike extremely). This caused partici-pants to focus on rating the words rather than on com-mitting the words to memory. Immediately after rating the words in the lists, participants were tested in one of two ways: (1) a test of explicit memory, in which they were asked to recall the words they had seen; or (2) a test of implicit memory, in which they were presented with three-letter fragments and were asked to add a few letters to create the rst word that came into their mind.The results of the recall experiment, shown in ● Figure 6.10a, show that the amnesia patients had poor recall compared to the two control groups. This poor recall con rms the poor explicit memory associ-ated with their amnesia. But the result of the implicit memory test, in Figure 6.10b, tells a different story. These results, which indicate the percentage of primed words that were created in the word completion test, demonstrates that the amnesia patient performed just as well as the controls. This shows that priming can occur even when there is little explicit memory for the words.Another example of repetition priming in a person with brain damage is an experi ment in which Elizabeth Warrington and Lawrence Weiskrantz (1968) tested ve patients with Korsakoff’s syndrome. The research-ers presented incomplete pictures, such as the ones in ● Figure 6.11 (Gollin, 1960), and the participant’s task was to identify the picture. The fragmented version in ● FIGURE 6.10 Results of the Graf et al. (1985) experiment. (a) The results of the recall test indicate that the amnesic patients (AMN) did poorly on the test compared to the medical inpatients (INPT) and the alcoholic controls (ALC). (b) The results of the implicit memory test, in which the task was to complete three-letter word stems, shows that the amnesic patients performed as well as the other patients. (Source: P. Graf, A. P. Shimamura, & L. R. Squire, “Priming Across Modalities and Priming Across Category Levels: Extending the Domain of Preserved Function in Amnesia,” Journal of Experimental Psychology: Learning, Memory, and Cognition, 11, 386–396, 1985.)INPT ALC AMN50403020100Percent words recalledRecall Implicit memory test(a)INPT ALC AMN50403020100Percent words completed(b)33559_06_ch06_p146-169.indd 16233559_06_ch06_p146-169.indd 162 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Priming, Procedural Memory, and Conditioning (Implicit)
163Figure 6.11a was presented rst, and then participants were shown more and more complete versions (b, c, d, and e) until they were able to identify the picture.The results, shown in ● Figure 6.12, indicate that by the third day of testing these participants made fewer errors before identify-ing the pictures than they did at the beginning of training, even though they had no memory for any of the previous day’s training. The improvement of performance represents an effect of implicit memory because the patients learned from experience even though they couldn’t remember having had the experience.Implicit memory is not simply a laboratory phenomenon, but also occurs in everyday experience. An example of a situation in which implicit memory may affect our behavior without our awareness is when we are exposed to advertisements that extol the virtues of a product or perhaps just present the product’s name. Although we may believe that we are unaffected by some advertisements, they can have an effect just because we are exposed to them.This idea is supported by the results of an experiment by T. J. Perfect and C. Askew (1994), who had participants scan articles in a magazine. Each page of print was faced by an advertisement, but participants were not told to pay attention to the advertisements. When they were later asked to rate a number of advertisements on various dimensions, such as how appealing, eye-catching, distinctive, and memorable they were, they gave higher ratings to the ones they had been exposed to than to other advertisements that they had never seen. This result quali es as an effect of implicit memory because when the participants were asked to indicate which advertisements had been presented at the beginning of the experiment, they recognized only an average of 2.8 of the original 25 advertisements.This result is related to the propaganda effect, in which participants are more likely to rate statements they have read or heard before as being true, simply because they have been exposed to them before. This effect can occur even when the person is told that the statements are false when they rst read or hear them (Begg et al., 1992). The propaganda effect involves implicit memory because it can operate even when people are not aware that they have heard or seen a statement before, and may even have thought it was false when they rst heard it.● FIGURE 6.11 Incomplete pictures developed by Gollin (1960) that were used by Warrington and Weiskrantz (1968) to study implicit memory in patients with amnesia. (Source: E. K. Warrington & L. Weiskrantz, “New Method of Testing Long-Term Retention With Special Reference to Amnesic Patients,” Nature, London, 217, March 9, 1968, 972–974, Figure 1. Copyright © 1968 Nature Publishing Group. Republished with permission.)(a) ©(b) (d)(e)● FIGURE 6.12 Results of Warrington and Weiskrantz’s (1968) experiment. (Source: Based on E. K. Warrington & L. Weiskrantz, “New Method of Testing Long-Term Retention With Special Reference to Amnesic Patients,” Nature, 217, 972–974, March 9, 1968.)3020100Error score123Day of trainingPerformance improveseven though the persondoesn’t remembertraining33559_06_ch06_p146-169.indd 16333559_06_ch06_p146-169.indd 163 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 6 Long-Term Memory: Structure Later in our discussion of LTM, espe-cially in Chapter 8, we will see how implicit memory can lead to memory errors. We will see, for example, that eyewitnesses to crimes have identi ed people as having been at the crime scene not because they were actually there, but because the eyewitnesses had seen them somewhere else at another time, so they seemed familiar.PROCEDURAL MEMORYProcedural memory is also called skill memory because it is memory for doing things that usually require action. The implicit nature of procedural memory has been demonstrated in amnesia patients who can master a skill without remem-bering any of the practice that led to this mastery (like the improvement in the pic-ture completion task in Figure 6.11). For example, H.M., whose amnesia was caused by having his hippocampus removed (see page 138), practiced a task called mirror drawing, which involves copying a picture that is seen in a mirror (● Figure 6.13). You can appreciate this task by doing the fol-lowing demonstration.DEMONSTRATION Mirror DrawingDraw a star like the one in Figure 6.13 on a piece of paper. Place a mirror or some other re ec-tive surface (some cell phone screens work) about an inch or two from the star, so that the re ection of the star is visible. Then, while looking at the re ection, trace the outline of the star on the paper (no fair looking at the actual drawing on the paper!). You will probably nd that the task is di cult at rst, but becomes easier with practice.After a number of days of practice, H.M. became quite good at mirror drawing, but each time he did it, he thought he was practicing it for the rst time. H.M.’s ability to trace the star in the mirror, even though he couldn’t remember having done it before, illustrates procedural memory.Other amnesia patients also demonstrate procedural memory. Jimmy G. could still tie his shoes, and Clive Wearing, who was a professional musician, was able to play the piano. In fact, people who can’t form new long-term memories can still learn new skills. K.C., who had lost his episodic memory because of a motorcycle accident (see page 158), learned how to sort and stack books in the library after his injury. Even though he doesn’t remember learning to do this, he can still do it, and his performance can improve with practice. The fact that people with amnesia can retain skills from the past and learn new ones has led to an approach to rehabilitating patients with amnesia by teaching them tasks, such as sorting mail or repetitive computer-based tasks, that they can become expert at, even though they can’t remember their training (Bolognani et al., 2000; Clare & Jones, 2008).We can also understand the implicit nature of procedural memory from our own experience. We do not remember where or when we learned many of our basic skills; nonetheless, we usually have little trouble doing them. Also, people can do things with-out being consciously aware of how they do them. For example, can you explain how ● FIGURE 6.13 Mirror drawing. The task is to trace the outline of the star while looking at its image in the mirror.33559_06_ch06_p146-169.indd 16433559_06_ch06_p146-169.indd 164 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Something to Consider
165 you keep your balance when riding a bike? What about tying your shoes? Tying shoes is so easy for most people that they do it without even thinking about it. If you think you are aware of how you do it, describe which lace you loop over the other one, and then what you do next. Most people have to either tie their shoes or visualize tying their shoes before they can answer this question.Riding a bike and tying your shoes are both motor skills that involve movement and muscle action. You have also developed many purely cognitive skills that qualify as involving procedural memory. Consider, for example, your ability to read the sentences in this book. Can you describe the rules you are following for creating sentences from the words and creating meaningful thoughts from the sentences? Unless you’ve studied linguistics, you probably don’t know these rules, but that doesn’t stop you from being a skilled reader.Finally, consider the plight of the concert pianist who, when he tried to become conscious of how he was moving his ngers as he played a dif cult passage, found that he was no longer able to play the passage. For many skills, the best practice is to disen-gage the mind and let implicit procedural memory take over!CLASSICAL CONDITIONINGClassical conditioning occurs when the following two stimuli are paired: (1) a neutral stimulus that initially does not result in a response and (2) a conditioning stimulus that does result in a response (see page 10). An example of classical conditioning from the laboratory is presenting a tone to a person followed by a puff or air to the eye that causes the person to blink. The tone initially does not cause an eyeblink, but after a number of pairings with the puff of air, the tone alone causes an eyeblink. This is implicit memory because it can occur even if the person has forgotten about the original pairing of the tone and air puff. The example we cited for Cliff on page 157 involved a situation in which the neutral stimulus was red cars and the conditioning stimulus was the accident that caused an emotional reaction. Having an emotional reaction to the previous neutral cars is an effect of classical conditioning. Conditioned emotional responses similar to what Cliff experienced can cause people to have emotional reactions to people, places, or events, even when they are unaware of the reasons for their reactions.We have described a number of different types of long-term memory, ranging from vivid memories of personal experiences (episodic, explicit) to the ability to ride a bicycle (procedural, implicit). Each of these types of long-term memories has been the subject of a great deal of research devoted to discovering how events can leave an imprint in the mind that later results in an experience (a memory) or a behavior (a skill or reaction to a speci c stimulus). In addition to being the subject of research, which we will discuss further in Chapters 7 and 8, memory has also been the subject of many movies over the years, most often stories in which a main character has suffered a loss of memory. Something to ConsiderMemory Loss in the MoviesCountless movies have featured a character with memory loss. The accuracy of these depictions, compared to actual cases, ranges from depictions that resemble types of mem-ory loss that actually occur to completely ctional types of memory loss that have never occurred. Sometimes, even when the memory loss in a movie resembles actual cases, it is described using incorrect terminology. We will describe some examples of fact-based memory loss, ctional memory loss, and the use of incorrect terminology in movies.In some movies, characters lose their memory for everything in their past, includ-ing their identity, but are able to form new memories. This is what happened to Jason Bourne, the character played by Matt Damon in The Bourne Identity (2002). In this 33559_06_ch06_p146-169.indd 16533559_06_ch06_p146-169.indd 165 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 6 Long-Term Memory: Structure lm, the unconscious and badly wounded Bourne is plucked out of the water by a shing boat. When he regains consciousness, he has no memory of his identity. As he searches for his previous identity, he realizes people are out to kill him, but, because of his memory loss, he doesn’t know why. Although Bourne has lost his episodic memories of his past, his semantic memory appears to be intact, and, most interesting of all, he has lost none of his procedural memories from his training as a CIA agent, including ways to outsmart, outrun, and eliminate his adversaries.Bourne’s situation is related to a rare condition called psychogenic fugue. Symptoms of this condition include traveling away from where the person lives and a lack of mem-ory for the past, especially personal information such as name, relationships, place of residence, and occupation. In the few cases that have been reported, a person vanishes from his or her normal life situation, often travels far away, and takes on a new identity unrelated to the previous one (Coons & Milstein, 1992; Loewenstein, 1991).A number of other movies revolve around a central character who loses his or her identity or takes on a new one. In Who Am I? (1998), Jackie Chan, a top secret soldier, loses his memory in a helicopter crash, triggering a quest to recover his identity. In Dead Again (1991), a mystery woman played by Emma Thompson can’t remember anything about her life. In The Long Kiss Goodnight (1996), Geena Davis plays a suburban homemaker who begins remembering events from her previ-ous life as a secret agent after suffering a blow to her head.In other movies, the main character has trouble form-ing new memories. For example, Lenny, the character played by Guy Pearce in Memento (2000), continually forgets what has just happened to him. This situation is based on cases such as those of Clive Wearing and Jimmy G., who were unable to form new memories and were therefore only able to remember the current one or two minutes of their lives. Lenny’s problem is apparently not as debilitating as in these real-life cases, because he is able to function in the outside world, although with some dif culty. To compensate for his inability to form new memories, Lenny records his experi-ences with a Polaroid camera and has key facts tattooed on his body (● Figure 6.14).The use of terminology in movies that is not the same as that used by psychologists is seen in Memento, where Lenny’s problem is identi ed as a loss of short-term memory. This re ects a common belief (at least among those who have not taken a cognitive psychology course) that forgetting things that have happened within the last few minutes or hours is a breakdown in short-term memory. Cognitive psychologists, in contrast, identify short-term memory as memory for what has happened in the last 15–30 seconds (or longer, if the events are rehearsed). According to that de nition, Lennie’s short-term memory was ne, because he could remember what had just happened to him. His problem was that he couldn’t form new long-term memories, so, like Clive Wearing and Jimmy G., he forgot everything that had happened more than a few minutes previously.Although some movies, like the ones already mentioned, are based at least loosely on actual memory disorders, some stray farther into ction. Douglas Quaid, the char-acter played by Arnold Schwarzenegger in Total Recall (1990), lives in a future world in which it is possible to implant memories. Quaid makes the mistake of having an arti cial memory of a holiday on Mars implanted, which triggers a series of nightmar-ish events.The reverse of creating speci c memories is selectively forgetting speci c events. This occasionally occurs, as when memories for particularly traumatic events are lost (although sometimes the opposite happens, so traumatic events stand out in memory; Porter & Birt, 2001). But the characters in The Eternal Sunshine of the Spotless Mind (2004) take the idea of selective forgetting to an extreme, by purposely undergoing a high-tech procedure to selectively eliminate their memory for a previous relationship. ● FIGURE 6.14 Guy Pearce’s character, Lenny, from the ﬁ lm Memento. To deal with his memory problem, he had key facts he wanted to remember tattooed on his body.© Keline Howard/Sygma/Corbis33559_06_ch06_p146-169.indd 16633559_06_ch06_p146-169.indd 166 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
167 First Clementine, played by Kate Winslet, has her memory for her ex-boyfriend, Joel, played by Jim Carrey, erased. When Joel discovers she has done this, he decides to undergo the same procedure to have Clementine erased from his memory. The after-math of this procedure is both thought provoking and entertaining!The movie 50 First Dates (2004) is an example of a memory movie based on a condition that exists only in the imagination of the lmmaker. Lucy, played by Drew Barrymore, remembers what is happening to her on a given day (so her short-term and long-term memory are ne during the day), but every morning she contracts a case of retrograde amnesia, which has wiped out her memory for what happened the day before. The fact that her memory “resets” every morning seems not to bother Henry, played by Adam Sandler, who falls in love with her. Strangely enough, even though Lucy wakes up every morning with no memory for the previous day, and therefore shouldn’t remember Henry, she develops a fondness for him. This behavior—respond-ing positively to Henry without remembering him—is an example of implicit memory.All of the movies we have described are ctional and so can take liberties with the facts for the purposes of entertainment. However, knowing about how memory actu-ally works can help us sort out what might be at least somewhat plausible from what is wildly ctional.1. How are episodic and semantic memory distinguished from each other?2. Describe the following evidence for the idea that semantic and episodic memo-ries involve different mechanisms: (a) neuropsychological evidence; (b) brain imaging evidence.3. What are the connections between episodic and semantic memory?4. What is priming, and why is it called a type of implicit memory? What pre-cautions are taken to be sure episodic memory is not accessed in an implicit memory experiment? What is repetition priming? Conceptual priming?5. Describe the Graf and the Warrington and Weiskrantz priming experiments. How do these experiments demonstrate that their participants are not aware of the initial priming stimuli?6. What is the propaganda effect, and why could it be considered a form of priming?7. What is procedural memory? Describe the mirror drawing experiment and other examples from the chapter. Why is procedural memory considered a form of implicit memory?8. What is classical conditioning? Why is it a form of implicit memory?9. Describe how memory loss is depicted in movies. How accurate are these depictions?CHAPTER SUMMARYTEST YOURSELF 6.2 1. Long-term memory is an “archive” of information about past experiences in our lives and knowledge we have learned, but it is important to consider the dynamic qualities as well, such as how LTM coordi-nates with working memory to help create our ongoing experience. 2. The primacy and recency effects that occur in the serial position curve have been linked to long-term memory and short-term memory, respectively. 3. The following evidence supports the idea that STM and LTM are two separate processes: (a) differences in the primary mode of coding, with LTM more likely than STM to be coded semantically; (b) neuropsychological studies that demonstrate dissociations between STM and LTM; and © brain imaging studies that demonstrate dif-ferent patterns of activity for STM and LTM. 4. Explicit memory is our conscious recollection of events we have experienced or facts we have learned. There are 33559_06_ch06_p146-169.indd 16733559_06_ch06_p146-169.indd 167 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 6 Long-Term Memory: Structure two types of explicit memory: Episodic memory is mem-ory for personal events in our lives; semantic memory is memory for facts and knowledge. 5. Implicit memories are memories used without awareness. Types of implicit memory are priming, procedural mem-ory, and classical conditioning. 6. According to Tulving, the defining property of the expe-rience of episodic memory is that it involves mental time travel (self-knowing or remembering). The experience of semantic memory (knowing) does not involve mental time travel. 7. The following evidence supports the idea that episodic and semantic memory involve different mechanisms: (a)double dissociation of episodic and semantic memory in patients with brain damage; (b) brain imaging, which indicates that overlapping but different areas are acti-vated by episodic and semantic memories. 8. Even though episodic and semantic memories are served by different mechanisms, they are connected in the fol-lowing ways: (a) Episodic memories can be lost, leaving semantic memory; (b) semantic memory can be enhanced by association with episodic memory; © semantic mem-ory can influence attention, and therefore what informa-tion we take in and potentially remember later. 9. Implicit memory occurs when previous experience improves our performance on a task, even though we do not remember the experience. Tulving calls implicit memory nonknowing. 10. Priming occurs when the presentation of a stimulus affects a person’s response to the same or a related stimulus when it is presented later. There are two main types of priming: repetition priming and conceptual priming. 11. The demonstration of implicit memory depends on show-ing that a particular change in behavior has occurred without participants’ consulting their episodic memory (because then the memory would not be unconscious, as required if it is an implicit memory). Various techniques can be used to achieve this; the most effective is to use amnesiac patients as participants. 12. Implicit memory is not just a laboratory phenomenon, but also occurs in real life. The propaganda effect is one example of real-life implicit memory. 13. Procedural memory, also called skill memory, has been studied in amnesiac patients. They are able to learn new skills, although they do not remember learning them. Procedural memory is a common component of many of the skills we have learned. 14. Classical conditioning occurs when a neutral stimu-lus is paired with a stimulus that elicits a response, so that the neutral stimulus than elicits the response. Classically conditioned emotions occur in everyday experience. 15. Memory loss has been depicted in movies in a number of ways, some of which bear at least a resemblance to actual cases of amnesia, and some of which are totally fictional conditions.Think ABOUT IT 1. What do you remember about the last 5 minutes? How much of what you are remembering is in your STM while you are remembering it? Were any of these memo-ries ever in LTM? 2. On page 155, we described the case of K.F., who had normal LTM but poor STM. What problem does K.F.’s condition pose for the modal model of memory? Can you think of a way to modify the model that would han-dle K.F.’s condition? 3. Not all long-term memories are alike. There is a differ-ence between remembering what you did 10 minutes ago, 1 year ago, and 10 years ago, even though all of these memories are called “long-term memories.” What kinds of investigations could you carry out to demonstrate the properties of these different long-term memories? 4. Rent movies like Memento, 50 First Dates, or oth-ers that depict memory loss. (Search the Internet for “Movies amnesia” for films in addition to those listed in the book.) Describe the memory loss depicted in these movies, and compare the problem depicted with the cases of memory loss described in this chapter. Determine how accurately depictions of memory loss in movies correspond to memory loss that occurs in actual cases of trauma or brain damage. You may have to do some additional research on memory loss to answer this question.If You WANT TO KNOW MORE 1. Top-down processing and the suffix effect. The suffix effect occurs when a sound presented at the end of a list of words decreases the recency effect in the serial posi-tion curve. This effect can depend on the participant’s interpretation of the meaning of the sound, which means that top-down processing can be involved in this effect.33559_06_ch06_p146-169.indd 16833559_06_ch06_p146-169.indd 168 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
169 Neath, I., Surprenant, A. M., & Crowder, R. G. (1993). The con-text-dependent stimulus suffix effect. Journal of Experimental Psychology: Learning, Memory and Cognition, 19, 698–703. 2. The “unitary” view of memory. Not all researchers accept the idea that short-term memory and long-term memory are separate processes. There are other theories, sup-ported by evidence, that propose one system, centered on long-term memory, and propose that a great deal of what is called short-term memory occurs when information is retrieved from long-term memory.Cowan, N. (2000). The magical number 4 in short-term mem-ory: A reconsideration of mental storage capacity. Behav-ioral and Brain Sciences, 24, 87–185.Jonides, J., Lewis, R. L., Nee, D. E., Lustig, C. A., Berman, G, & Moore, K. S. (2008). The mind and brain of short-term memory. Annual Review of Psychology, 59, 193–224. 3. Memory loss in Alzheimer’s disease. Patients with Alzheimer’s disease experience progressive loss of mem-ory as different structures are attacked by the disease.Fleischman, D. A., & Gabrieli, J. (1999). Long-term memory in Alzheimer’s disease. Current Opinion in Neurobiology, 9, 240–244.Fleischman, D. A., Wilson, R. S., Gabrieli, J. D. E., Schneider, J. A., Bienias, J. L., & Bennett, D. A. (2005). Implicit mem-ory and Alzheimer’s disease: Neuropathology. Brain, 128, 2006–2015.Gilboa, A., Ramirex, J., Kohler, S., Westmacott, R., Black, S. E., & Moscovitch, M. (2005). Retrieval of autobiographi-cal memory in Alzheimer’s disease: Relation to volumes of medial temporal lobe and other structures. Hippocampus, 15, 535–550. 4. Mental time travel in animals. Experiments with scrub jays, rats, and nonhuman primates have demonstrated parallels in their behavior to behaviors associated with mental time travel in humans.Roberts, W. A., & Feeney, M. C. (2009). The comparative study of mental time travel. Trends in Cognitive Science, 13, 271–277.Key TERMSAnterograde amnesia, 149Classical conditioning, 157Conceptual priming, 161Declarative memory, 156Episodic memory, 156Explicit memory, 156Implicit memory, 156Korsakoff’s syndrome, 149Long-term memory (LTM), 149Mental time travel, 158Nondeclarative memory, 156Primacy effect, 151Priming, 156Procedural memory, 157Propaganda effect, 163Recency effect, 153Recognition memory, 154Repetition priming, 161Retrograde amnesia, 149Semantic memory, 156Serial position curve, 151Media RESOURCESThe Cognitive Psychology Book CompanionWebsitewww.cengage.com/psychology/goldsteinPrepare for quizzes and exams with online resources— including a glossary, ashcards, tutorial quizzes, crossword puzzles, and more.CogLabTo experience these experiments for yourself, go to coglab.wadsworth.com. Be sure to read each experiment’s setup instructions before you go to the experiment itself. Otherwise, you won’t know which keys to press.Primary LabsSerial position How memory for a list depends on an item’s position on the list (p. 151).Implicit learning How we can learn something without being aware of the learning (p. 161).Related LabSuﬃ x eﬀ ect How adding an irrelevant item to the end of a list affects recall for the nal items on a list in a serial position experiment.33559_06_ch06_p146-169.indd 16933559_06_ch06_p146-169.indd 169 13/04/10 6:14 PM13/04/10 6:14 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Long-Term Memory: Encoding and RetrievalWhat is the best way to put information into your memory through studying, and then to access this information later when you need to remember it for the test? The answer to this question involves basic principles of memory that are described in thischapter.33559_07_ch07_p170-201.indd 17033559_07_ch07_p170-201.indd 170 14/04/10 4:26 PM14/04/10 4:26 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
171 © iStockphoto.com/JuanmoninoENCODING: GETTING INFORMATION INTO LONG-TERM MEMORYMaintenance Rehearsal and Elaborative RehearsalLevels-of-Processing Theory DEMONSTRATION: Remembering Lists METHOD: Varying Depth of ProcessingResearch Showing That Encoding Influences Retrieval DEMONSTRATION: Reading a ListTEST YOURSELF 7.1RETRIEVAL: GETTING INFORMATION OUT OF MEMORYRetrieval Cues METHOD: Cued RecallMatching Conditions of Encoding and RetrievalTEST YOURSELF 7.2HOW TO STUDY MORE EFFECTIVELYElaborateGenerate and TestOrganizeTake BreaksMatch Learning and Testing ConditionsAvoid “Illusions of Learning”MEMORY AND THE BRAINExperiences Cause Changes at the SynapseWhere Does Memory Occur in the Brain?Forming Memories in the Brain: The Process of ConsolidationSOMETHING TO CONSIDER: ARE MEMORIES EVER “PERMANENT”?TEST YOURSELF 7.3CHAPTER SUMMARYTHINK ABOUT ITIF YOU WANT TO KNOW MOREKEY TERMSMEDIA RESOURCES33559_07_ch07_p170-201.indd 17133559_07_ch07_p170-201.indd 171 14/04/10 4:26 PM14/04/10 4:26 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 7 Long-Term Memory: Encoding and Retrieval What is the best way to store information in long-term memory? (173) What are some techniques we can use to help us get information out of long-term memory when we need it? (181) How can the results of memory research be used to create more effective study techniques? (187) How is it possible that a lifetime of experiences and accumulated knowledge can be stored in neurons? (190)Some Questions We Will ConsiderW I T “W I use memory for,” “Remembering material for exams” was at the top of the class’s list (see Chapter 5, page 116). This is, of course, important (your grade depends on it!), and students have therefore devised numerous ways to get the information they need to know into memory. In the previous edition of this book, I invited students to send, by e-mail, their favorite study techniques. Here are excepts from a few of the responses I received:STUDENT #1: The main technique I use to study is to make up a story in my mind, basically a fake memory, the type a person would use to create an effective lie, in order to remember material. An example of this strategy is how I studied for our rst cogni-tive psych exam this semester. “Jo changed his name to Hermann Helmholtz today. Jo has always been an odd one. He always infers things are there that aren’t. Like the time he liked that girl Amygdala. Speaking of Amygdala, she was an emotional girl.” When I tell this story to myself I create an image, much like a memory to associate with what I am trying to remember. That way when I take the test an entire sequence of events is recalled so that I am better able to remember the information. (Elizabeth Eowyn Waibel, University of Wisconsin)STUDENT #2: I like to go to class early and study in the classroom. To remember, I need to take notes from the book as I read. For certain harder classes, I remember better if I do this before class. Then during class I just add to my previous notes. This lets me listen more during class instead of being busy writing. . . . I like to start conversations with my parents or friends about what I’ve learned in class. They have usually learned something about it too, and remind me of details I may have forgotten. (Kristin Eddinger, Florida Atlantic University)STUDENT #3: A technique I’ve used has been to nd someone unsuspecting, perhaps a friend or family member, and teach them what I’ve learnt. I did this to a mate about 5years ago, taught him about the structure of the tooth. To this day he remembers it and always reminds me of the time I jumped him with this “random” information! (Brigitte Dunbar, Massey University, Auckland, New Zealand)STUDENT #4: My tactic is to go through my textbook (and lecture notes) and to create a sort of “tabbed” set of notes, where sub-concepts are tabbed underneath larger concepts. This follows the organization of textbooks to a degree . . . so I get something like Declarative Memory–Episodic–About events in our lives–Semantic–About facts. . . . After reading a few paragraphs, I write down what I learned, but rst I have to gure out the major and minor points. But the most important part about this is it acts as a way to test myself. I can just throw a piece of paper over my notes and slowly move it down the page, and I try to recall what is “inside” a certain heading (and explain it to myself), and then I go down it line by line to check ( if I missed a sub-heading, I try to recall what’s under it, if anything). (Taylor Murphy, University of Alberta)STUDENT #5: I read each chapter, take notes (sometimes word for word, or by short-hand) on my computer where I can organize them in a way that makes sense to me. Finally, I make note cards and study these. (Natalie Tyler, Georgia State University)33559_07_ch07_p170-201.indd 17233559_07_ch07_p170-201.indd 172 14/04/10 4:27 PM14/04/10 4:27 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Encoding: Getting Information Into Long-Term Memory
173 Each of the techniques suggested by these students is based on one or more basic principles behind the operation of long-term memory. In this chapter we begin by describing these principles and then show how the principles can be applied to the student examples and to studying in general. One of the goals of studying is to get infor-mation into LTM. We saw in Chapter5, when we described Rachel ordering pizza, that the process of acquiring information and transferring it into LTM is called encoding.Notice that the term encoding is similar to the term coding that we discussed in relation to STM in Chapter 5 and LTM in Chapter 6. Some authors use these terms interchangeably. We will use the term coding to refer to the form in which information is represented. For example, a word can be coded visually or by its sound or by its meaning. We will use the term encoding to refer to the process used to get information into LTM. For example, a word can be encoded by repeating it over and over, by think-ing of other words that rhyme with it, or by using it in a sentence. One of the main mes-sages in this chapter is that some methods of encoding are more effective than others.Imagine that you’ve just nished studying for an exam and are pretty sure that you have encoded the material that is likely to be on the exam into your LTM. But the moment of truth occurs when you are in the exam and you have to remember some of this information to answer a question. This remembering involves accessing some of the information that you’ve encoded and transferring it from LTM into working memory, to become consciously aware of it. This process of transferring information from LTM to working memory is called retrieval. It is, of course, essential to your success on the exam, because even if information is in LTM, it doesn’t help you answer the exam question if you can’t retrieve it. One of the main factors that determines whether you can retrieve information from LTM is the way that information was encoded when you learned it. In the next section we will focus on how information is encoded into LTM. We will then consider retrieval and how it relates to encoding.Encoding: Getting Information Into Long-Term MemoryThere are a number of ways to get information into memory, some more effective than others. You can mindlessly read something, or take in its deeper meaning; you can consider a topic by repeating its individual points, or you can become aware of how a topic is organized by noting how the individual points relate to each other. We begin describing methods of getting information into memory by discussing the process of rehearsal—repeating information over and over.MAINTENANCE REHEARSAL AND ELABORATIVE REHEARSALOne of the central concerns of early cognitive psychologists was determining the rela-tionship between encoding and rehearsal. We saw in Chapter 5 that rehearsal can be used to keep information in STM/working memory, as when you repeat a phone number you have just looked up in the phone book. Although rehearsal can keep information in working memory, rehearsal doesn’t guarantee that information will be transferred into LTM. You know this from your experience in rehearsing a telephone number and then forgetting it right after you place the call. When you rehearse a telephone number in this way, you are usually just repeating the numbers without any consideration of meaning or making connections with other information. This kind of rehearsal, called maintenance rehearsal, helps maintain information in STM/WM, but it is not an effec-tive way of transferring information into long-term memory.Another kind of rehearsal, elaborative rehearsal, is more effective at transferring information into LTM; it occurs when you think about the meaning of an item or make connections between the item and something you know. We can demonstrate that elaborative rehearsal is a good way to establish long-term memories by describing an approach to memory called levels-of-processing theory.33559_07_ch07_p170-201.indd 17333559_07_ch07_p170-201.indd 173 14/04/10 4:27 PM14/04/10 4:27 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 7 Long-Term Memory: Encoding and Retrieval LEVELS-OF-PROCESSING THEORYIn 1972 Fergus Craik and Robert Lockhart proposed the idea of levels of processing (LOP). According to levels-of-processing theory, memory depends on how information is encoded, with “deeper” processing resulting in better encoding and retrieval than “shallow” processing. In other words, memory depends on how information is pro-grammed into the mind.The Basics of Levels of Processing According to levels-of-processing theory, depth of processing is determined by the nature of the task during encoding. The following demonstration illustrates how different tasks affects memory for a list of words.DEMONSTRATION Remembering ListsPart 1. Cover the list below and then uncover each word one by one. Your task is to count the number of vowels in each word and then go right on to the next one. Once you get to the end of the list, cover it and follow the instructions at the end of the list.chairmathematicselephantlampcarelevatorthoughtfulcactusInstructions: Count backward by 3s from 100. When you get to 76, write down the words you remember. Do that now.Part 2. Cover the list below and uncover each word one by one as you did in the previous part. This time, visualize how useful the item might be if you were stranded on an uninhabited island. When you get to the end of the list, follow the instructions.umbrellaexerciseforgivenessrockhamburgersunlightco eebottleInstructions: Count backward by 3s from 99. When you reach 75, write down the words you remember. Do that now.Which procedure resulted in better memory, counting the number of vowels or visu-alizing an item’s function? Most of the experiments that have asked this kind of ques-tion have found that memory is superior when a meaningful connection has been made between an item and something else. Thus, memory for words is better when the words are processed by relating them to other knowledge, such as how useful an object might be on an uninhabited island, than when processed based on a nonmeaningful characteristic such as the number of vowels. Craik and Lockhart’s levels-of-processing theory states that memory depends on the depth of processing that an item receives. They describe depth of processing by distinguishing between shallow processing and deep processing.Shallow processing involves little attention to meaning. Shallow processing occurs when attention is focused on physical features, such as whether a word is printed in Levels of Processing33559_07_ch07_p170-201.indd 17433559_07_ch07_p170-201.indd 174 14/04/10 4:27 PM14/04/10 4:27 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Encoding: Getting Information Into Long-Term Memory
175lowercase or capital letters, or the number of vowels in a word, as was done in Part 1 of the “Remembering Lists” demonstration. Shallow processing also occurs during mainte-nance rehearsal, in which an item is repeated to keep it in memory but without consider-ing its meaning or its connection with anything else.Deep processing involves close attention, focusing on an item’s meaning and relat-ing it to something else. Considering how an item might be useful in a particular situ-ation, as was done in Part 2 of the demonstration, or creating an image of the item in relation to another item would create deep processing. This way of processing an item occurs during elaborative rehearsal and, according to levels-of-processing theory, results in better memory than shallow processing.The previous demonstration illustrated one way of varying depth of processing. The following Method, which corresponds to the method used in an experiment by Fergus Craik and Endel Tulving (1975), illustrates how depth of processing can be var-ied by asking different kinds of questions about a word.METHOD Varying Depth of ProcessingThe procedure for the Craik and Tulving experiment is diagrammed in ● Figure 7.1a. A question was presented, followed by a word, and then the participant responded. Shallow processing was achieved by asking questions about the word’s physical characteristics; deeper processing was achieved by asking about the word’s sound; and the deepest processing was achieved by a task that involved the word’s meaning. The following examples are similar to those used in Craik and Tulving’s experiment.1. Shallow processing: A question about physical features of the wordQuestion: Is the word printed in capital letters?Word: bird2. Deeper processing: A question about rhymingQuestion: Does the word rhyme with train?Word: pain3. Deepest processing: A fill-in-the-blanks questionQuestion: Does the word t into the sentence “He saw a on the street”?Word: carAfter participants responded to questions like the ones above, they were given a memory test to see how well they recalled the words. The results, shown in Figure 7.1b, indicate that deeper processing is associated with better memory.The idea of levels of processing motivated a great deal of research that investigated how the way a stimulus is encoded affects the abil-ity to retrieve it later. However, the levels-of- processing theory and the idea of depth of processing became less important to memory researchers when it became apparent that it was dif cult to de ne exactly what depth of processing is.The Di culty in De ning Depth of Processing The way we have described depth of process-ing is based mainly on common sense: It seems obvious that paying attention to how a word is used in a sentence would be “deeper” than (a)Ask question.Example:Capital letters?Presentword.Example: BirdAnswerquestion.Example: No(b)Fill inblanksRhyme?10050Percent correct0Capital letters?● FIGURE 7.1 (a) Sequence of events in Craik and Tulving’s (1975) experiment. (b) Results of this experiment. Deeper processing (ﬁ ll-in-the-blanks question) is associated with better memory.33559_07_ch07_p170-201.indd 17533559_07_ch07_p170-201.indd 175 14/04/10 4:27 PM14/04/10 4:27 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
CHAPTER 7 Long-Term Memory: Encoding and Retrieval noting if the word is printed in capital letters. But let’s consider a more dif cult problem. What about using a word in a sentence (as in the Craik and Tulving experiment) versus deciding how useful an object might be on a desert island (as in the Demonstration). Which of these results in deeper processing? Unfortunately, levels-of- processing theory does not offer a way to answer this question.One possibility that might be worth trying is to pit these two procedures against each other in a memory experiment. If, in our hypothetical experi-ment, participants in the desert island condition remember more than participants in the ll-in-the-blanks condition, then couldn’t we conclude that the desert island condition resulted in deeper pro-cessing? Although this may sound logical, a little re ection indicates that this procedure does not really solve the problem. We can appreciate why by considering the reasoning behind the memory experiment more closely.We started by asking whether the desert island task causes deeper or shallower processing than the fill-in-the-blanks task. To answer this question, we ran a memory experiment and determined that the desert island task resulted in better memory (● Figure 7.2a). From this, we concluded that the desert island task results in deeper process-ing (Figure 7.2b). This seems to have solved the problem, but not so fast! Once we have determined that the desert island task results in deeper processing, we can predict from this that memory will be better for the desert island task (Figure 7.2c). This is called circular reasoning, and it occurs because depth of processing has not been defined independently of memory performance. We can’t use memory performance to determine depth of processing and then turn around and use depth of processing to predict memory performance.Because no procedure was offered to de ne depth of processing independently of memory performance, levels-of-processing theory became less popular with memory researchers. But the main conclusion of levels-of-processing theory—that memory retrieval is affected by how items are encoded—is still widely accepted, and a great deal of research has been done that demonstrates this relationship.RESEARCH SHOWING THAT ENCODING INFLUENCES RETRIEVALA number of different procedures have been used to show that encoding can affect retrieval. The basic idea in all of these experiments is to vary encoding and measure how retrieval (memory performance) is affected. We will show how this has been done in experiments that involve (1) placing words to be remembered in complex sentences; (2) forming visual images based on words; (3) forming links between words and per-sonal characteristics; (4) generating information; (5) organizing information; and (6) testing.Placing Words in a Complex Sentence If you were given the task of remembering the word chicken, which sentence do you think would result in better memory?1. She cooked the chicken.2. The great bird swooped down and carried off the struggling chicken.Craik and Tulving (1975) found that memory for a word is much better when the word is presented in a complex sentence. Their explanation for this result is that the ● FIGURE 7.2 The circularity of deﬁ ning depth of processing in terms of memory and then predicting that deeper processing will result in better memory. See text for details.Can thereforeconclude thatCan thereforepredict that© Memory will bebetter following thedesert island task.(a) Result: Memory isbetter following thedesert island task.(b) Desert islandtask causes deeperprocessing.33559_07_ch07_p170-201.indd 17633559_07_ch07_p170-201.indd 176 14/04/10 4:27 PM14/04/10 4:27 PMCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.
Encoding: Getting Information Into Long-Term Memory