Cognitive Development Throughout the Lifespan Chapter 13 PDF
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This chapter explores cognitive development throughout the lifespan, including memory, metamemory, and language development in infants, children, and the elderly. It highlights the cognitive abilities of young children and emphasizes development as an ongoing process throughout life.
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13 Cognitive Development throughout the Lifespan Chapter Introduction The Lifespan Development of Memory Memory in Infants Memory in Children Memory in Elderly People The Lifespan Development of Metamemory Metamemory in Children Metamemory in Elderly People The Development of Language L...
13 Cognitive Development throughout the Lifespan Chapter Introduction The Lifespan Development of Memory Memory in Infants Memory in Children Memory in Elderly People The Lifespan Development of Metamemory Metamemory in Children Metamemory in Elderly People The Development of Language Language in Infants Language in Children Chapter Introduction A friend described an interesting example of her granddaughter’s cognitive sophistication. Five-year-old Isabelle had been on a family outing to go ice skating, a new experience for her. As they left the skating rink, Isabelle said, “That wasn’t as much fun as I thought it was going to be.” This chapter examines cogni- tive development in three areas, and Isabelle’s remark reveals her expertise in all of these areas. 1. Memory: Isabelle remembers her original expectation that ice skating would be fun. 2. Metacognition: Isabelle had predicted that the skating experience would be fun. 3. Language: Isabelle’s description successfully navigates among the three time periods, beginning with her anticipation of an enjoyable skating experience, and then the actual (not-so-enjoyable) skating experience, and finally her current acknowledgment of the discrepancy between the first and second time periods. This interaction captures the considerable cognitive potential of young children. It also illustrates Theme 1 of this textbook, because children actively pursue information, and they try to make sense of their experiences (Gelman & Frazier, 2012). Why should we study the cognitive processes of infants and children? One reason is theoretical: This research helps us understand the origins of cognitive skills, as well as the evolution of more complex skills (Gelman & Frazier, 2012; Rovee-Collier & Cuevas, 2009a). Another reason is practical: Many of you will have careers that require background knowledge about infancy and childhood. It’s important to note, however, that development isn’t limited to infants, children, and young adults. In reality, we never stop developing—that is, we continue to change and adapt throughout our entire lives (Smith & Baltes, 1999; Whitbourne & Whitbourne, 2011). In today’s world, humans are living longer than ever before, and the percentage of older adults has increased dramatically in recent years (U.S. Census 287 288 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN Bureau, 2012a). With this shift in population dynamics, cognitive psychologists have started to focus on how cognitive processing abilities change as people enter their older years (often defined in the field of cognitive aging as adults who are 65 or older). Some cognitive skills decline during the aging process, but many other capabilities remain stable. Understanding which cognitive processes change as adults age— along with the factors that drive those changes—can provide information that may directly inform many real-life issues facing aging adult populations. This chapter focuses on cognitive development in three areas: memory, metamemory, and language. I organized this textbook so that the final chapter would encourage you to review many of the major con- cepts from these three important areas within cognitive psychology. As you’ll also learn, infants and young children possess cognitive skills that you might not expect. In addition, you’ll see that elderly people are much more cognitively competent than the popular stereotype suggests (Whitley & Kite, 2010). The Lifespan Development of Memory Theme 5 of this textbook highlights that many of our cognitive abilities depend upon both sensory-based bottom-up processes and knowledge-driven top-down processes. But, these processes aren’t fully devel- oped at birth. Instead, complex interactions between the properties of an organism’s biological make-up and its environment drive the emergence of cognitive abilities over time. And, in many respects, we never really stop developing. Information newly acquired through the mechanisms that drive learning and devel- opment will influence how we perceive, interpret, and interact with our environments on subsequent occa- sions. Thus, in our final chapter on cognitive development, we take a lifespan approach to development. That is, we focus not only on development in infancy and young childhood, but instead on developmental issues that occur throughout one’s lifetime, including adulthood and older adulthood. When we study the cognitive abilities of infants, children, and elderly adults, the research problems are more complex than when we study young adults. For example, how can young infants convey their cogni- tive abilities, given their limited language and motor skills? With creative research techniques, however, researchers can partially overcome these limitations and discover that even young infants can understand information about the people and objects in their world (e.g., Gelman & Frazier, 2012; Mandler, 2004a; Rovee-Collier & Cuevas, 2009a, 2009b). Research with elderly individuals presents a different set of methodological problems (Boker & Bisconti, 2006; Whitbourne & Whitbourne, 2011). Hundreds of studies have compared the cognitive performance of young, healthy college students with the performance of elderly people. And yet, across-group differences in health, self-confidence, formal education, and familiarity with technology may serve as confounding variables. For example, suppose that older adults perform less well on a cognitive processing task—such as a memory task—than college students. In such a case, it is often unclear whether the differences are due to cognitive decline as opposed to across-group differences in these potentially confounding variables. In general, researchers believe that confounding variables can explain a major proportion of the differences in cognitive performance between college students and older adults. That said, researchers have identified some age-related differences that persist, even when they eliminate confounding variables (Rabbitt, 2002; Salthouse, 2012; Whitbourne & Whitbourne, 2011). Chapters 4–6 focused specifically on memory, and the remaining chapters frequently discussed how memory contributes to other cognitive processes. In this first section, we now focus on how memory devel- ops during infancy (the first two years of life), childhood, and old age. Memory in Infants Try to picture an infant who is about four months old—not yet old enough to sit upright without support. Would you expect that this baby would recognize his or her mother or remember how to make a mobile move? Several decades ago, psychologists believed that infants as young as four months of age could not remember anything for more than a brief period (Gelman, 2002). Of course, we cannot expect young infants to demonstrate sophisticated memory feats, because regions of the cortex most relevant to working memory and long-term memory are not yet fully developed (Bauer, 2004; Kagan & Herschkowitz, 2005). Furthermore, early researchers underestimated infants’ memory capacities because of methodological problems. Fortunately, current developmental psychologists have devised several research methods to test The Lifespan Development of Memory 289 infants’ ability to remember people and objects (Gelman & Frazier, 2012; Reznick, 2009). This research shows that infants have greater memory capabilities than you might expect. For example, we now know that six-month-old infants can create an association between two objects, even if they have never previ- ously seen the objects together at the same time and even if they were never reinforced for creating these associations (Cuevas et al., 2006; Giles & Rovee-Collier, 2011). One way to assess infants’ memory is to see whether they look longer at one stimulus than another (e.g., Kibbe & Leslie, 2011; Sangrigoli & de Schonen, 2004). Let’s consider two other research techniques that demonstrate infants’ memory skills: (1) recognizing mother and (2) conjugate reinforcement with a mobile. As you’ll see, babies can demonstrate substantial memory ability, even during their first month of life. Recognizing Mother Research on visual recognition shows that three-day-old infants can distinguish their mother from a stran- ger (Rovee-Collier et al., 2001; Slater & Butterworth, 1997). Additionally, infants’ ability to recognize their mother’s voice is especially remarkable (Markowitsch & Welzer, 2010; Siegler et al., 2003). Kisi- levsky and her coauthors (2003), for example, tested infants about one or two weeks before they were born. Specifically, these researchers approached pregnant women who were receiving prenatal care at a hospital in China. The researchers asked each woman about testing her infant’s voice-recognition ability, while she was still pregnant. If the mother agreed, the researchers presented either the mother’s voice reading a Chinese poem or a female stranger’s voice reading the same poem. Impressively, the infants’ heart rate changed more when they listened to their mother’s voice, rather than the stranger’s voice. Conjugate Reinforcement Obviously, young infants cannot verbally tell us that they remember something they saw earlier. Carolyn Rovee-Collier and her colleagues designed a nonverbal measure to assess infant memory. Many studies now use this conjugate reinforcement technique to examine infant memory (Markowitsch & Welzer, 2010; Ornstein & Haden, 2009; Rovee-Collier & Cuevas, 2009a, 2009b). In the conjugate reinforce- ment technique, a mobile hangs above a young infant’s crib; a ribbon connects the infant’s ankle and the mobile, so that the infant’s kicks will make the mobile move (see Figure 13.1). This game is especially appealing to two- to six-month-old infants. After several minutes, they begin to kick rapidly and pump up the mobile. Then, the infants lie quietly and watch parts of the mobile move. In loving memory of Carolyn Rovee-Collier. FIGURE 13.1 The conjugate rein- forcement setup in Rovee-Collier’s research. 290 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN As the movement dies down, they typically shriek and then kick vigorously, thereby pumping it up again. In operant conditioning terms, the response is a foot kick, and the reinforcement is the movement of the mobile (Barr et al., 2005; Rovee-Collier & Cuevas, 2009a, 2009b). Let’s see how the conjugate reinforcement technique can be used to assess infant memory. All the training and testing take place in the infant’s crib at home, so that measurements are not distorted by the infant’s reactions to the new surroundings. For a three-minute period at the beginning of the first ses- sion, the experimenter takes a baseline measure. During this time, the ribbon is connected from the infant’s ankle to an “empty” mobile stand, rather than to the mobile. Thus, the experimenters can measure the amount of spontaneous kicking that occurs in the presence of the mobile, before the infant learns how to make the mobile move (Rovee-Collier & Barr, 2002; Rovee-Collier & Cuevas, 2009a). Next, the experimenter moves the ribbon so that it runs from the baby’s ankle to the stand from which the mobile is hung. The babies are allowed nine minutes to discover that their kicks can activate the mobile; this is the acquisition phase. The infants typically receive two training sessions like this, spaced 24 hours apart. At the end of the second training session, the ribbon is unhooked and returned to the empty stand for three minutes in order to measure what the infants remember. The number of kicks that the infant produces is a test of immediate retention. Researchers then measure long-term memory after 1 to 42 days have elapsed. The mobile is once again hung above the infant’s crib, with the ribbon hooked to the empty stand. Suppose that three-month-old Jason recognizes the mobile and recalls how his kicking had produced movement. Then, Jason will soon produce the foot-kick response. Notice, then, that Rovee-Collier devised a clever way to “ask” infants if they remember how to activate the mobile. She also devised an objective method for assessing long-term memory, because she can com- pare two measures: (1) the number of kicks produced in the immediate retention test and (2) the number of kicks produced following the delay. Rovee-Collier later devised a second operant conditioning task that is more appealing to infants between the ages of six and 18 months. In this second task, older infants learn to press a lever in order to make a miniature train move along a circular track. By combining information from the two tasks, researchers can trace infant memory from two months through 18 months of age (Barr et al., 2011; Hsu & Rovee-Collier, 2006; Rovee-Collier & Barr, 2002). Figure 13.2 shows how much time can pass before infants no longer show significant recall for the relevant task. For example, six-month-olds can recall how to move the mobile and also how to move the 13 12 11 10 Maximum retention (weeks) 9 8 FIGURE 13.2 Train task The maximum duration 7 for which different 6 groups of infants dem- onstrated significant 5 retention. In this study, two- to six- 4 month-old infants kicked to activate a mobile, and 3 six- to 18-month-old infants 2 Mobile task pressed a lever to activate a train. 1 Source: Rovee-Collier, C. K. (1999). The development 0 of infant memory. Current 2 3 6 9 12 15 18 Directions in Psychological Science, 8, 80–85. Age (months) The Lifespan Development of Memory 291 train, even after a two-week delay. This research demonstrates that long-term retention shows a steady, linear improvement during the first 18 months of life (Hsu & Rovee-Collier, 2006). Several decades ago, researchers thought that infant memory was extremely limited. However, Rovee- Collier and her coworkers have demonstrated that infants can remember actions, even after a substantial delay. Furthermore, infant memory and adult memory are influenced by many of the same factors (Barr et al., 2011; Rovee-Collier & Barr, 2002; Rovee-Collier & Cuevas, 2009a, 2009b; Rovee-Collier et al., 2001). For example, you saw in Chapter 5 that context sometimes influences adult memory. Context effects are even stronger for infants. Rovee-Collier and her colleagues (1985) used the conjugate reinforcement tech- nique to test three-month-old infants whose cribs were lined with a fabric that had a distinctive, colorful pattern. The infants’ delayed recall was significantly stronger when they were tested seven days later with the same, familiar crib liner, rather than an unfamiliar crib liner. Without the proper environmental con- text, infants’ memories decline sharply (Markowitsch & Welzer, 2010; Rovee-Collier & Cuervas, 2009a; Rovee-Collier & Hayne, 2000). In additional research, Rovee-Collier and her associates have discovered numerous other similarities between infant and adult memory. For example, in Chapter 6, we discussed the spacing effect: College students learn most effectively if their practice is distributed over time (spaced learning), rather than if they learn the material all at once (massed learning). A number of studies have demonstrated that infants can also remember better with distributed practice (Barr et al., 2005; Bearce & Rovee-Collier, 2006). In summary, a number of tasks allow infants to demonstrate their memory skills. For example, babies can recognize their mother’s voice, even prior to birth. Furthermore, six-month-olds can remember how to activate a mobile after a two-week delay, and some of the same factors that influence an adult’s memory also influence an infant’s memory. Memory in Children We have seen that researchers need to be extremely inventive when they study infant memory. By using the conjugate reinforcement technique and other creative methods, they have concluded that infants’ memory is reasonably impressive. Children can respond verbally, so it’s much easier to assess their memory than infants’ memory. How- ever, the task is still challenging. Young children may have trouble understanding the task instructions, and they might not recognize letters of the alphabet or printed words. With these problems in mind, let’s con- sider five topics: (1) children’s working memory, (2) their long-term memory, (3) their memory strategies, (4) their eyewitness testimony, and (5) the relationship between children’s intelligence and the accuracy of their eyewitness testimony. Children’s Working Memory Working memory is often measured in terms of memory span, or the number of items that can be cor- rectly recalled in order, immediately after presentation. Memory spans improve dramatically during childhood (Cowan & Alloway, 2009; Gathercole et al., 2006; Hitch, 2006). According to one estimate, for example, a two-year-old can recall an average of two numbers in a row, whereas a nine-year-old can recall six (Kail, 1992). By the age of 11 or 12, children’s working memory is even more impressive. In fact, under ideal conditions, typically developing children almost match the performance of college stu- dents (Cowan et al., 2009). As you saw in Chapter 4, Alan Baddeley (2006) and other theorists propose that adult working memory has three especially important components: the central executive, the phonological loop, and the visuospatial sketchpad. Susan Gathercole and her colleagues (2004) found that this same structural model also applies to the working memory of children as young as four, with older children, and with adolescents. As you might expect, children’s working-memory skills are correlated with their performance in school. For instance, children with high scores on phonological working memory are likely to excel in reading, writing, and listening (Alloway et al., 2005). Furthermore, children with high scores on visuospatial work- ing memory are likely to excel in mathematics (Gathercole & Pickering, 2000; Hitch, 2006). Now let’s turn our attention to long-term memory in children. Later, we see how older children’s use of memory strategies helps to explain the improvement in their memory performance. 292 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN Demonstration 13.1 Age Differences in Recall and Recognition In this study, you will need to test a college-age person and a pre- five seconds and then conceal it again. After you have shown all 10 school child. You should reassure the child’s parents that you are objects, ask each person to recall as many of the objects as possible. simply testing memory as part of a class project. Do not provide feedback about the correctness of the responses. After You will be examining both recall and recognition in this demon- recall is complete, test for recognition. Show one object at a time, stration. First, assemble 20 common objects, such as a pen, pencil, randomly presenting the old objects mixed in sequence with several piece of paper, leaf, stick, rock, book, key, apple, and so forth. Place new objects. For each item, ask whether the object is old or new. the objects in a box or cover them with a cloth. Count the number of correct recalls and the number of correct You will use the same testing procedure for both people, although recognitions for each person. You should find that both the child the preschool child will require a more extensive explanation. and the adult are quite accurate on the recognition measures, but the Remove 10 objects in all, one at a time. Show each object for about adult recalls more items than the child. Children’s Long-Term Memory With respect to long-term memory, young children typically have excellent recognition memory but rela- tively poor recall memory (e.g., Flavell et al., 2002; Howe, 2000; Schwenk et al., 2009). In a classic study, Myers and Perlmutter (1978) administered research tasks similar to those in Demonstration 13.1, using two- and four-year-old children. To test recognition, the researchers began by showing children 18 objects. Then, they presented 36 items, including the 18 previous objects as well as 18 new objects. The two-year- olds recognized an impressive 80% of the items, and the 4-year-olds recognized about 90% of the items. To examine recall, Myers and Perlmutter (1978) tested two additional groups of children. These research- ers began by showing the children nine items. The two-year-olds recalled only about 20% of the items, and the four-year-olds recalled about 40% of the items. Recall memory seems to require the active use of memory strategies. As you see later in this section, children do not develop these strategies until middle childhood (Schneider & Bjorklund, 1998). Let’s now consider two additional topics related to long-term memory: (1) autobiographical memory for events from childhood and (2) children’s source monitoring. 1. Autobiographical memory and early childhood. As we discussed in Chapter 5, autobiographical memory refers to your memory for experiences and information that are related to yourself (Brewin, 2011). When researchers study autobiographical memory in children, they emphasize how children link their previous experiences together. Children therefore create a personal history or “life narrative” (Fivush, 2011). Most children’s language skills grow rapidly as they approach the age of 2. These skills help them remember their personal experiences more accurately. Notice that this connection between language and memory is a good example of Theme 4 of your textbook. Children who are three years old can typically produce simple scripts to describe a recent experience (Howe et al., 2009; Hudson & Mayhew, 2009; Pipe & Salmon, 2009). As discussed in Chapter 8, a script is a simple, well-structured sequence of events—in a specified order—that are associated with a highly familiar activity (Baddeley et al., 2009). After the age of two, children are increasingly likely to reminisce about their previous experiences, especially with their parents (Fivush, 2011; Laible & Panfile, 2009). According to the research, when mothers encourage their children to provide detailed descriptions of events, these children are more likely to develop a narrative style that is detailed and coherent (Fivush, 2009, 2011). Now take a moment to answer this question: Can you clearly recall any events that happened when you were two or three years old? Are you sure that you’re not actually recalling another person’s description of this event? David Rubin (2000) located previous studies that had asked adolescents and adults to recall autobiographical memories from the first 10 years of their lives. As you can see in Figure 13.3, people seldom recalled events that happened when they were younger than 3. Recent studies confirm Rubin’s results (e.g., Fitzgerald, 2010; Janssen & Rubin, 2011; Markowitsch & Welzer, 2010; Peterson et al., 2011). The reason for this phenomenon is not clear, especially because two-year-old children frequently describe an event that occurred several weeks or months ago. This observation suggests that they must be able to store verbal memories for several months (Gauvain, 2001; Ornstein & Haden, 2001). One possibility is that children younger than 2 do not have a well-organized sense of who they are (Fivush & Nelson, 2004; Goodman & Melinder, 2007; Markowitsch & Welzer, 2010). The Lifespan Development of Memory 293 0.20 Proportion of memories per year 0.15 0.10 FIGURE 13.3 The proportion of 0.05 memories supplied by adolescents and adults that occurred for each year, 1 to 10 years of age. 0.00 Source: Rubin, D. C. (2000). 0 1 2 3 4 5 6 7 8 9 10 The distribution of early childhood memories. Age in memory Memory, 8, 265–269. As a result, they may have difficulty encoding and retrieving a series of events connected with themselves, when the interval is longer than several months (Newcombe et al., 2000). This explanation could be especially relevant, because the study by Rubin (2000) examined adolescents and adults. Apparently, they have trouble accessing their memories about early childhood. 2. Children’s source monitoring. Chapter 5 discussed source monitoring, which is the process of trying to identify the origin of a particular memory. In general, children younger than about seven years of age typically have more difficulty than adults in distinguishing between reality and pure fantasy (Foley, 2012; Ratner et al., 2001; Sluzenski et al., 2004). For example, I know an extremely bright child who had participated in an imaginary trip to the moon one day at school. Later that day, she insisted to her parents that she really had visited the moon. Children who are younger than seven years of age also have difficulty distinguishing between something they saw in real life, as opposed to something from a storybook or a video (Thierry et al., 2010). Research by Mary Ann Foley, Hilary Horn Ratner, and their colleagues has systematically clarified the conditions in which young children are most likely to make these source-monitoring errors. For example, Foley and Ratner (1998) asked one group of six-year-olds to perform specific physical activities, such as making a motion like an airplane. A second group of six-year-olds was instructed, “Try to imagine what it would actually feel like to do that.” A third group was instructed, “Try to picture what you look like....” According to the results, when children had actually performed an action, they seldom reported that they had simply imagined it. In contrast, when children had simply imagined an action, they often reported that they had actually performed it. The children who made the most source-monitoring errors were those who had imagined how it would feel to make airplane movements; they often convinced themselves that they had actually circled around the room. Other research on source monitoring shows that children sometimes recall that they had performed a task, when someone else had actually performed it (Foley, 2012; Foley, Ratner, & House, 2002; Ratner et al., 2001). Apparently, children between the ages of 4 and 6 can watch another person at work, and they anticipate the steps in the project. Later, they become confused, and they remember actually completing the project themselves. As you might guess, children’s source monitoring is especially poor if they are questioned a long time after the original event (Sluzenski et al., 2004). In another investigation of children’s source monitoring, Mary Ann Foley and her colleagues (2010) arranged to have pairs of four-year-old children work together on a task. These children took turns placing pieces of construction paper on a poster board to make a collage. Consistent with earlier research, children often claimed “I did it,” when the other child had actually made the placement. Incidentally, you might wonder if the children’s responses simply reflect an egocentric bias. However, the “I did it” bias seldom occurs when an adult and a child take turns (Foley, 2012). In one of these studies, the researcher asked the child to think what the adult would feel like, raising her arms and moving them like an airplane (Foley et al., 2010). This procedure provided a framework for 294 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN imagining the adult make other motor movements. Then, the researcher told the child to watch the adult placing each piece on the collage, and think what it would feel like to actually go through the motions of placing the piece. The results showed that these “feel like” instructions actually increased the likelihood that the child would claim, “I did it.” Notice, then, that preschool children seem to have a significant prob- lem with source monitoring. Children’s Memory Strategies So far, our exploration of children’s memory has demonstrated that young children are fairly similar to adults in recognizing items. However, children are much less accurate than adults in terms of recall and source monitoring. Adults have another advantage: When they want to remember something that must be recalled at a later time, they often use memory strategies. Here is one important reason that young children have relatively poor recall: They cannot use memory strategies effectively (Cowan & Alloway, 2009; Kail, 2010; Torbeyns et al., 2010). During elementary school, children become increasingly skilled in using these strategies (Bjorklund et al., 2009; Grammer et al., 2011). Memory strategies are intentional, goal-oriented activities that we use to improve our memories. Young children may not realize that strategies can be helpful. Their working memory may not be developed enough to choose a strategy and actually use it on a memory task (Torbeyns et al., 2010). Furthermore, some young children may not actually use the strategies effectively; this problem is called utilization deficiency (Pressley & Hilden, 2006). As a result, the strategies may not improve their recall (Ornstein et al., 2006; Schneider, 2002). In contrast, older children are more likely than younger children to realize that strategies are helpful. In addition, they choose their strategies more carefully and use them more consistently. Also, older children often use a variety of strategies when they need to learn several items, and they may monitor how they use these strategies (Bjorkland et al., 2009; Schneider, 1998). As a result, older children can recall items with reasonable accuracy. Let’s survey three major kinds of memory strategies: rehearsal, organization, and imagery. 1. Rehearsal, or merely repeating items over and over, is not a particularly effective strategy, but it may be useful for maintaining items in working memory. Research suggests that four- and five- year-olds do not spontaneously rehearse material they want to remember. However, seven-year-olds do use rehearsal strategies, often silently rehearsing several words together (Bjorklund et al., 2009; Gathercole, 1998; Schneider & Bjorklund, 1998). Another important point is that younger children can benefit from learning to use rehearsal strategies, even though they may not use these strategies spontaneously (e.g., Flavell et al., 2002; Gathercole, 1998). Children with reading disorders also tend to recall more items when they have been taught about rehearsal (Swanson et al., 2010). As we will see in the section on metamemory, young children often fail to realize that they could improve their memory performance by using strategies. 2. Organizational strategies, such as categorizing and grouping, are helpful for adults, as we saw in Chapter 6. However, young children are typically less likely than older children to spontaneously group similar items together to aid memorization (Flavell et al., 2002; Ornstein et al., 2006; Pressley & Hilden, 2006; Schwenck et al., 2009). Try Demonstration 13.2; are the children in your sample reluctant to adopt an organizational strategy? Demonstration 13.2 is based on a classic study by Moely and her colleagues (1969), in which children studied pictures from four categories: animals, clothing, furniture, and vehicles. During the two-minute study period, they were told that they could rearrange the pictures in any order they wished. Younger children rarely moved the pictures next to other similar pictures, but older children frequently organized the pictures into categories. The researchers specifically urged other groups of children to organize the pictures. Even the younger children saw that the organizational strategy was useful, and this strategy increased their recall. 3. Imagery, a topic discussed in Chapters 6 and 7, is an extremely useful device for improving memory in adults. Research shows that even six-year-olds can be trained to use visual imagery effectively (Foley et al., 1993; Howe, 2006). However, young children usually do not use imagery spontaneously. In fact, the spontaneous use of imagery does not develop until adolescence. Even most college students do not use this helpful strategy often enough (Pressley & Hilden, 2006; Schneider & Bjorklund, 1998). The Lifespan Development of Memory 295 Demonstration 13.2 Organizational Strategies in Children Make a photocopy of the pictures on this page and use scissors be rearranged in any order they want. After a four-minute study to cut them apart. In this study you will test a child between the period, remove the pictures and ask the child to list as many items ages of 4 and 8; ideally, it would be interesting to test children of as possible. Notice two things in this demonstration: (1) Does the several different ages. Arrange these pictures in random order in a child spontaneously rearrange the items at all during the study circle facing the child. Instruct him or her to study the pictures so period? (2) Does the child show clustering during recall, with sim- that they can be remembered later. Mention that the pictures can ilar items appearing together? In short, preschool children are unlikely to use memory strategies in a careful, consistent fashion. In fact, as we have suggested here—and will further discuss in connection with metamemory—young chil- dren seldom appreciate that they need to use memory strategies (Ornstein et al., 2006; Schneider, 1999). However, as children develop, they learn how to use memory strategies such as rehearsal, organization, and (eventually) imagery. It’s also worth mentioning that teachers can help children by showing them how to use age-appropriate memory strategies. Furthermore, teachers can use spaced rather than massed presentation in the classroom to improve their students’ recall (Seabrook et al., 2005). Children’s Eyewitness Testimony So far, we have examined children’s working memory, long-term memory, and memory strategies. We’ve seen that young children’s performance in those three areas is definitely inferior when compared with adults’ performance. This information has implications for an applied area of cognition, the accuracy of their eyewitness testimony. As you might guess, older children typically provide much more accurate eyewitness testimony than younger children (Melnyk et al., 2007; Pipe & Salmon, 2009; Schwartz, 2011). 296 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN A real-life court case inspired Michelle Leichtman and Stephen Ceci (1995) to conduct an experiment. In the original court case, a nine-year-old girl had provided eyewitness testimony, and it seemed likely that both stereotypes and suggestions could have influenced her report. Leichtman and Ceci’s classic study explored the impact of these two factors. Leichtman and Ceci tested 176 preschoolers, assigning each child to one of four conditions. In the con- trol condition, a stranger named Sam Stone visited the classroom, strolling around and making several bland comments for a period of about two minutes. In the stereotype condition, a research assistant presented one story each week to the children, for three weeks prior to Sam Stone’s visit. Each story emphasized that Sam Stone was nice but very clumsy. In the suggestion condition, the research assistant told the children two incorrect suggestions after Sam Stone’s visit—that Sam Stone had ripped a book and that he had spilled a chocolate drink on a white teddy bear. Finally, in the stereotype-plus-suggestion condition, children were exposed to both the stereotype before Sam Stone’s visit and the incorrect suggestions afterward. Ten weeks after Sam Stone’s classroom visit, a new interviewer asked the children what Sam Stone had done during his visit. The children were specifically asked whether they had actually seen Sam Stone tear up the book and spill the chocolate drink on the teddy bear. Figure 13.4 shows the percentage of children in each condition who said that they had witnessed at least one of these two events. Notice, first of all, that the children in the control group were highly accurate. In other words, children can provide valid eyewitness testimony if they do not receive misleading information, either before or after the target event (Bruck & Ceci, 1999; Schneider, 2002). As Figure 13.4 also shows, however, a worrisome number of children claimed that they had actually witnessed these actions, in the condition where the researchers had established a previous stereotype. Even more of the younger children claimed that they had actually witnessed the actions if they had received inaccurate suggestions after the event. The most worrisome data came from the younger children who had received both the stereotype and the suggestions. Almost half of the younger children falsely reported that they had seen Sam Stone damage either the book or the teddy bear. Other research confirms that the accuracy of children’s eyewitness testimony is influenced by the child’s age, stereotyping, and misleading suggestions (Melnyk et al., 2007; Memon et al., 2006; Roebers et al., 2005; Schwartz, 2011). As you might imagine, social factors can also have a major impact. For example, children make more errors when interviewers ask questions in a highly emotional tone or when the inter- viewer uses complex language (Bruck & Ceci, 1999; Imhoff & Baker-Ward, 1999; Melnyk et al., 2007). 50% Percentage reporting events that had not occurred 3- and 4-year-olds 5- and 6-year-olds 40% 30% FIGURE 13.4 The effects of stereo- 20% types and suggestions on young children’s eyewitness testimony. Graph shows the percentage 10% who reported actually seeing events that had not occurred. 0% Source: Leichtman, M. D., & Ceci, S. J. (1995). The 0% effects of stereotypes and Control Stereotype Suggestion Stereotype- suggestions of preschoolers’ plus-suggestion reports. Developmental Psychology, 31, 568–578. Experimental condition The Lifespan Development of Memory 297 In addition, children are extremely reluctant to say, “I don’t know” when an adult asks a question (Bruck & Ceci, 1999). Furthermore, children are likely to change their statements if someone cross-examines them, and this tendency is stronger among five- and six-year-olds than among nine- and 10-year-olds (Zajac & Hayne, 2006). Children’s Intellectual Abilities and Eyewitness Testimony So far, this chapter has focused on typically developing children, and we have seen that the accuracy of children’s eyewitness testimony increases as they grow older. What happens for children with intellec- tual disabilities? Lucy Henry and Gisli Gudjonsson (2007) studied children in England, who were either enrolled in special schools for children with intellectual disabilities or enrolled in mainstream schools. In each of these two groups, they tested children who were an average of either nine years two months old or 12 years 8 months old. All the children saw a three-minute video clip that featured four people pulling up to a gas station in a car, filling up the car with gas, and driving off without paying for the gas. Each child then performed a short irrelevant task, and then the researcher asked the child to describe as much as possible about the video. The researchers scored the recall narrative in terms of the total number of correct items supplied by the child. As Table 13.1 shows, older children recalled more items than the younger children. Furthermore, this age difference was especially strong for the typically developing children. In addition, Henry and Gudjonsson (2007) asked some specific misleading questions, for example, about the color of the police car, even though there was no police car. In this misleading-question situa- tion, the older children made the same number of errors as the younger children. However, within each age group, the typically developing children provided a greater number of correct answers and a smaller number of errors in response to misleading questions. These results are consistent with the outcomes of other research (e.g., Pipe & Salmon, 2009). However, Henry and Gudjonsson (2007) point out that there was only a short delay period between see- ing the event and providing eyewitness testimony. Further research would need to include a longer delay, consistent with the real-life situations in which children are asked to supply eyewitness testimony. Memory in Elderly People The popular stereotype for elderly people is that they may be pleasant, but they are typically forgetful and cognitively incompetent (Cuddy & Fiske, 2002; Hess et al., 2003; Levy & Banaji, 2002). Here’s an exam- ple of this stereotype (Hulicka, 1982). A 78-year-old woman served a meal to her guests, and the meal was excellent, except that she had used bleach instead of vinegar in the salad dressing. Her concerned relatives attributed the error to impaired memory and general intellectual decline, and they discussed placing her in a nursing home. As it turned out, someone else had placed the bottle of bleach in the cupboard where the vinegar was kept. Understandably, the woman had reached for the wrong bottle, which was similar in size, shape, and color to the vinegar bottle. Some time later, the same people were guests in another home. A young woman in search of hair spray reached into a bathroom cabinet and found a can of the correct size and shape. She proceeded to drench her hair with Lysol. In this case, however, no one suggested that the younger woman should be institutional- ized; they merely teased her about her absentmindedness. In mainstream North American culture, people often believe that elderly people have substantial cog- nitive deficits. Unfortunately, this stereotype can lead elderly people to think that they actually are less Table 13.1 The Number of Correct Items Supplied by Children in Free Recall Average age of child Category of children 9 years 2 months 12 years 8 months Children with intellectual disability 7.2 items 13.6 items Typically developing children 18.9 items 34.5 items Source: Henry, L. A., & Gudjonsson, G. H. (2007). Individual and developmental differences in eyewitness recall and suggestibility in children with intellectual disabilities. Applied Cognitive Psychology, 21, 361–381. 298 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN competent. As a result, elderly people may remember less information (Moulin & Gathercole, 2008; Whitbourne & Whitbourne, 2011; Zacks & Hasher, 2006). The research on age-related changes in memory has increased dramatically during the last 10 years, and we now have a wide variety of review articles and books (e.g., Bialystok & Craik, 2006; Erber, 2005; Park & Reuter-Lorenz, 2009; Whitbourne & Whitbourne, 2011). However, the research shows large indi- vidual differences and complex developmental trends in various components of memory. Let’s first con- sider the research on working memory and long-term memory in elderly people. Then, we will examine some potential explanations for the memory changes during aging. Working Memory in Elderly People How well do elderly adults perform on tasks requiring working memory, when they need to retain information in memory for less than a minute? You’ve probably noticed that your psychology professors frequently use the phrase, “It all depends on....” In the case of working memory, factors such as the nature of the task determine whether we find age similarities or age differences (Whitbourne & Whitbourne, 2011). In general, we find age similarities in working memory when the task is relatively straightforward and requires simple storage. In contrast, we typically find age differences when the task is complicated and requires manipulation of information (Park & Payer, 2006; Schwartz, 2011; Whitbourne & Whitbourne, 2011; Zacks & Hasher, 2006). For example, younger and older adults perform similarly on a standard digit-span test of working memory. On these tasks, people are instructed to recall a list of numbers in order (Bäckman et al., 2001; Dixon & Cohen, 2003; Fabiani & Wee, 2001). In contrast, age differences are substantial on a working-memory task in which people must ignore irrelevant information, manipulate information, or perform two simultaneous tasks (Cansino et al., 2011; Carstensen, 2007; Kramer & Kray, 2006; Schwartz, 2011). For instance, in one study, people were given short lists of unrelated words, with the instructions to remember them, and report these words in correct alphabetical order (Craik, 1990). On this complex task, the average young participant reported 3.2 correct items on the alphabetical-order task, whereas the average elderly participant reported 1.7 correct items. Incidentally, an occupation that requires superb working memory is air traffic controller. U.S. regulations require controllers to retire at age 56, a policy that is clearly appropriate (Salthouse, 2012). Long-Term Memory in Elderly People Do elderly people differ from younger adults in their long-term memory? Once again, the answer depends on the characteristics of the task. In general, elderly people perform quite well on tests of semantic memory (Park & Reuter-Lorenz, 2009; Schwartz, 2011; Whitbourne & Whitbourne, 2011; Zacks & Hasher, 2006). In fact, a study by Salthouse (2012) showed that 50- to 80-year-olds actually perform better than 30- to 40-year-olds on crossword puzzles. Elderly individuals also tend to perform well on tasks that they can do relatively automatically (Economou et al., 2006; Little et al., 2004). However, age differences emerge on more challenging tasks, such as source monitoring (Mitchell & Johnson, 2009; Whitbourne & Whitbourne, 2011). In this discussion of long-term memory, we consider four topics: (1) prospective memory, (2) implicit memory, (3) explicit recognition memory, and (4) explicit recall memory. 1. Prospective memory. Chapter 6 discussed prospective memory, or remembering to do something in the future. In general, older adults have difficulty on many prospective-memory tasks (Scullin et al., 2011; Zimmermann & Meier, 2010). For example, one prospective-memory task—high in ecological validity—simulates a shopping task. Participants saw a list of items they were supposed to purchase. For example, when they saw an image of a fast-food restaurant, they were supposed to “buy” a hamburger. On these tasks, younger adults successfully completed a greater number of tasks than the older adults (Farrimond et al., 2006; McDermott & Knight, 2004). Why would older adults tend to make more errors on prospective-memory tasks? One important reason is that prospective memory relies heavily on working memory. People need to keep reminding themselves to do the relevant task, and—as we saw earlier—older adults often show a decline in working memory. In contrast, older adults perform relatively accurately when they have an environmental cue, such as a book placed near the door, reminding them to take it to the library (Einstein & McDaniel, 2004; Scullin et al., 2011). Occasionally, older adults even perform more accurately than younger adults, for example, when instructed to take a certain medicine on a daily basis (Park & Hedden, 2001; Park et al., 1999). The Lifespan Development of Memory 299 2. Implicit Memory. Chapter 5 pointed out that an explicit memory task requires people to remember information that they have previously learned. In contrast, an implicit memory task requires people to perform a perceptual or cognitive task (e.g., to complete a series of word fragments); previous experience with the material facilitates their performance on the task. In a representative study, Light and her colleagues (1995) measured implicit memory in terms of the amount of time that the participants needed to read a letter sequence that was either familiar or unfamiliar. People demonstrated implicit memory if they read a familiar sequence faster than an unfamiliar sequence. On this implicit memory task, adults between the ages of 64 and 78 performed just as well as the younger adults, who were between the ages of 18 and 24. Other research on implicit memory shows either similar performance by younger adults, or else just a slight deficit for older adults (e.g., Economou et al., 2006; Park & Reuter-Lorenz, 2009; Whitbourne & Whitbourne, 2011; Zacks & Hasher, 2006). Thus, age differences are minimal when the memory task does not require effortful remembering. 3. Recognition Memory. The research shows that long-term recognition memory declines either slowly or not at all, as people grow older (Burke, 2006; Erber, 2005; Moulin et al., 2007; Schwartz, 2011). For example, a classic study on recognition memory found that 20-year-olds correctly recognized 67% of words that had been presented earlier. On this same task, the 70-year-olds recalled a nearly identical 66% of the words (Intons-Peterson et al., 1999). 4. Explicit Recall Memory. So far, our discussion of long-term memory has shown that elderly people often have difficulty with prospective memory, but they perform reasonably well on two kinds of long-term memory tasks: (1) implicit memory and (2) recognition memory. Let us now turn to performance on explicit recall tasks. Here, the differences between a young adult and an older adult are frequently more substantial (Brown, 2012; Schwartz, 2011; Zacks & Hasher, 2006). Consider a study by Alaitz Aizpurua and her colleagues (2009). These researchers compared college students (age range = 19 to 25 years) with people who were enrolled in a college course designed for older adults (age range = 56 to 72 years). Notice that the researchers chose appropriate comparison groups for this study. In fact, the two groups were similar in the number of years of formal education and also similar in their self-rated health. The participants in this study watched a short video of a robbery. After a short delay, they were given 10 minutes to recall the events from the video. The results showed that the older adults recalled less infor- mation than the younger adults. However, the two age groups were similar in (1) the number of events they described that did not occur in the video and (2) the nature of these errors. Elderly individuals differ widely in their performance on long-term recall tasks. For example, peo- ple with low verbal ability and little education are more likely to show a decline in recall as they grow older. In contrast, age differences are minimal for people who have high verbal ability and are well educated (Manly et al., 2003; Rabbitt, 2002). Suppose that the two groups in the previous study had differed greatly in both education and health. The memory differences would have been substantially larger. Lynn Hasher and her coauthors have explored another variable that can influence researchers’ conclu- sions about age differences in memory. This variable is the time of day when people’s memory is tested (Hasher et al., 2002; Zacks & Hasher, 2006). Specifically, older adults tend to function relatively well when they are tested in the morning. In contrast, older adults make substantially more memory errors than younger adults when both groups are tested in the afternoon. Interestingly, most research on memory is scheduled for afternoons, so the data underestimate the memory of older adults. So, are older people more likely than younger people to have trouble with their long-term memory? As you can see, it’s impossible to provide a simple answer. Instead, the research results are consistent with the “It all depends on....” principle. Elderly people are fairly similar to younger people on implicit memory tasks and on recognition tasks. What happens when we examine an area in which age differences are more prominent, for example, on an explicit recall task? Here we cannot draw a simple conclusion. For instance, highly verbal, well- educated elderly people perform relatively well. Elderly people also perform relatively well when tested in the morning. 300 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN In other words, memory deficits are far from universal among elderly people. In fact, Zacks and Hasher (2006) end their chapter on aging and long-term memory with the following statement: “Taken together, these recent findings suggest that we may have seriously underestimated the memory abilities of older adults” (p. 174). Explanations for Age Differences in Memory We have examined a complex pattern of age-related memory effects. On some tasks, young people remem- ber better than older people; in other cases, the age differences are minimal. As you might expect, this complex pattern of effects requires a complex explanation, rather than just one straightforward cause. 1. Neurocognitive changes. Research in cognitive neuroscience demonstrates that some changes in brain structures occur during normal aging. Remember that explicit recall memory is especially likely to show a deficit. From a neuroscience perspective, this makes sense, because explicit recall relies on a complex network of different brain structures. Because parts of the brain must work together, explicit recall memory can be disrupted if one component of the network is not functioning appropriately. Furthermore, many of these brain structures are known to decrease in volume during normal aging (Moulin et al., 2007; Park & Reuter-Lorenz, 2009). Surprisingly, however, the research with elderly individuals shows increased activation in the frontal lobe, even though its actual size may decrease. This frontal-lobe activation helps to compensate for some of the age-related decreases in other parts of the brain (Park & Reuter-Lorenz, 2009). Let’s now consider several psychological processes that help to explain the pattern of changes in memory performance during normal aging. To account for these changes, we would need to identify several mechanisms, because no single explanation would be sufficient (Moulin et al., 2007). 2. Difficulty paying attention. In general, the research suggests that elderly adults are more likely than younger adults to have difficulty paying attention (Guerreiro & Van Gerven, 2011; Mueller- Johnson & Ceci, 2007; Whitbourne & Whitbourne, 2011). In fact, when elderly adults work on a standard memory task, they often perform about the same as when young adults work on a memory task that requires divided attention (Naveh-Benjamin et al., 2005; Naveh-Benjamin et al., 2007). 3. Less effective use of memory strategies. Elderly people could have impaired memory because they use memory strategies and metamemory less effectively. Some research suggests that elderly adults construct fewer chunks in working memory, compared to younger adults (Naveh-Benjamin et al., 2007). As you may recall from Chapter 4, a chunk is a memory unit that consists of several components that are strongly associated with one another (Schwartz, 2011). If elderly people have trouble using working-memory strategies, they are likely to make errors on tasks such as prospective memory and explicit recall. In contrast, many studies conclude that elderly adults and young adults use similar memory strategies in long-term memory (Dunlosky & Hertzog, 1998; Light, 2000). Therefore, the strategy- deficit hypothesis cannot explain age differences in long-term memory. 4. The contextual-cues hypothesis. As we saw earlier, elderly people perform relatively well on recognition tasks. Contextual cues are present on recognition tasks, because researchers display an item, and the participants report whether they had seen it previously. In other words, these contextual cues can encourage recognition for elderly individuals. In contrast, contextual cues are absent on explicit recall tasks; instead, these recall tasks require people to use effortful, deliberate processing. The research shows that young adults are relatively skilled in remembering contextual cues, such as where they were and what date it was when they heard a particular news item (Grady & Craik, 2000; Light, 2000). These contextual cues may therefore boost the accuracy of young adults’ explicit recall. In contrast, we noted that elderly adults typically recall fewer contextual cues. Therefore, elderly adults must rely on effortful, deliberate processing in order to retrieve the information, and the explicit recall task is more challenging. 5. Cognitive slowing. A final explanation is one that has been acknowledged for decades: Elderly people often experience cognitive slowing, or a slower rate of responding on cognitive tasks (e.g., Bunce & Macready, 2005; Einstein & McDaniel, 2004; Schwartz, 2011). The cognitive- slowing explanation can account for some of the age-related differences in memory, but it cannot fully explain why elderly people function relatively well on some other memory tasks. The Lifespan Development of Metamemory 301 In summary, several hypotheses can each explain some portion of the memory differences between older and younger adults. Perhaps researchers will develop a more refined version of several of these hypotheses, or they may propose additional hypotheses. At this point, we currently have a com- plex set of findings about memory in elderly individuals, but no comprehensive explanation for these results. The Lifespan Development of Metamemory As we discussed in Chapter 6, metacognition is a term that refers to your thoughts about thinking; it is your knowledge about your cognitive processes, as well as your control of these cognitive processes. One important kind of metacognition is metamemory, a term that refers to your knowledge, monitoring, and control of your memory. Another kind of metacognition is called theory of mind, a term that refers to your ideas about how your mind works, as well as how other people’s minds work. For example, you know that other people hold certain beliefs that are different from your own. However, young children have trouble with this concept (Dunlosky & Metcalfe, 2009; Schneider & Lockl, 2008; Schwartz, 2011). A third kind of metacognition is metacomprehension, a term that refers to your thoughts about your comprehension, such as your understanding of written material or spoken language. Although there are a small number of exceptions (e.g., Baker et al., 2010; Hacker et al., 2009), researchers have not explored metacomprehension in children or elderly individuals. In this chapter, we therefore focus specifically on metamemory in children and elderly people. Metamemory in Children In this discussion of children’s metamemory, we examine children’s beliefs about how their memory works, their awareness that learning requires an effort, and their judgments about their own memory per- formance. Then, we discuss how metamemory is related to memory performance. Children’s Understanding of How Memory Works An important component of metamemory is a person’s knowledge about how memory works. Demonstration 13.3 includes some questions about this aspect of children’s metamemory. Try this dem- onstration when you have an opportunity. You may need to simplify the questions for young children, because their responses might be influenced by their limited language skills (Fritz et al., 2010). Demonstration 13.3 Metamemory in Children Locate a child who is at least five years old, and ask the following dog chair flower sky ball bicycle apple pencil house car questions about his or her memory. Compare the accuracy and the completeness of the answers with your own responses. If the child Suppose that you memorize a friend’s address. Will you is young, you may need to modify the wording. remember the address better after 2 minutes have passed or after 2 Suppose that a child named Katie is supposed to bring her days have passed? favorite book to school tomorrow. She is afraid that she might forget Two children want to remember a list of words. One child has to bring it. What kind of things can she do to make sure that she a list of 10 words, and the other has a list of five words. Which brings the book to school? child will be more likely to remember all the words on the list Suppose that I decide to read you a list of 10 words. How many correctly? words do you think that you could remember, in the correct order? Suppose that a boy named Bob is telling you a story about a (Then, read the following list fairly slowly, and count how many birthday party he went to. Later on, you tell this story to a friend. words the child recalls correctly. If the child is young, substitute the Would it be easier for you to tell the whole story word for word? Or number “5” for “10” and read only the first five words.) would it be easier for you to tell the main idea about the story? 302 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN Children often have unsophisticated ideas about some aspects of their memory (Fritz et al., 2010; Larkin, 2010). For example, seven-year-olds are not yet aware that words are easier to remember when they are related to one another, rather than randomly selected (Schneider & Pressley, 1997). Furthermore, when young children are taught to use a memory strategy, they often fail to realize that the strategy actually improved their memory performance (Bjorklund, 2005). If children don’t know how their memory works, they won’t know how to plan effective study strategies (Bjorklund, 2005; Schneider, 2002). Children’s Awareness That Effort Is Necessary Another important component of metamemory is the awareness that memory is not an automatic process. Instead, you need to make an effort, if you really want to remember something (Bjorklund, 2005; Schwartz, 2011). Unfortunately, young children do not appreciate this principle. Furthermore, they are not accurate in judging whether they have successfully committed some information to memory. They typically report to the experimenter that they have satisfactorily memorized a list, yet they recall little on a test (Pressley & Hilden, 2006). In addition, children often fail to realize that they need to make an effort to use a memory strategy. However, they are more likely to successfully use a memory strategy if they have received instructions about why the strategy should help their memory (Pressley & Hilden, 2006). Older children also have naive ideas about the effort required in memorization. I recall a visit from an 11-year-old in our neighborhood who had been memorizing some information about the U.S. Con- stitution. My husband asked her how she was doing and whether she would like him to quiz her on the material. She replied that she knew the material well, but he could quiz her if he wanted. Her recall turned out to be minimal for both factual and conceptual information. She had assumed that by allow- ing her eyes to wander over the text several times, the material had magically worked its way into her memory. Children’s Judgments about Their Memory Performance In general, young children are extremely overconfident when they assess their memory performance. In contrast, older children are somewhat more accurate (Dunlosky & Metcalfe, 2009; Keast et al., 2007; Larkin, 2010; Schneider & Lockl, 2008). For example, Claudia Roebers and her colleagues (2004) gathered measures of metamemory as part of their larger study on children’s eyewitness testimony. Children between the ages of five and 10 years of age watched a live magic show, which lasted eight minutes. One week later, an interviewer met with each child individually and asked a series of 56 questions about the show. In this study by Roebers and her colleagues, a typical question was, “Where did the magician get the bag from?” (p. 326). After answering each question, children rated how confident they were that their answer had been correct. Specifically, they used a rating scale consisting of five cartoon faces. The facial expressions varied from a very frowning face (“very unsure,” corresponding to a rating of 1) to a very smiling face (“very sure,” corresponding to a rating of 5). Figure 13.5 shows the results. As you can see, when children answered a question correctly, all three age groups were very sure that their answer had been correct. In contrast, when they answered a question incorrectly, they should have circled either the very frowning face or the somewhat frowning face. Notice that even the older children were overconfident that their incorrect answer had been correct. However, this overly optimistic assessment may be adaptive: If children knew that their performance had been so dismal, they would not persist on a difficult task (Dunlosky & Metcalfe, 2009). Children’s Metamemory: The Relationship between Metamemory and Memory Performance Let us summarize several observations from this chapter that are related to memory in young children: 1. Their metamemory is faulty; they do not realize that they need to make an effort to memorize, and they also do not realize how little they can remember. 2. They do not spontaneously use helpful memory strategies. 3. Relative to older children, their performance on a memory test is poor. The Lifespan Development of Metamemory 303 Questions answered correctly 5.0 Questions answered incorrectly items answered correctly and incorrectly Average confidence judgments for 4.0 FIGURE 13.5 Average level of 3.0 confidence for questions answered correctly and questions answered incorrectly. (1 = Very unsure; 2.0 5 = Very sure). Source: Roebers, C. M., Gelhar, T., & Schneider, W. (2004). “It’s magic!” The effects of presentation modality on children’s event memory, suggestibility, 1.0 and confidence judgments. 5- and 6- 7- and 8- 9- and 10- Journal of Experimental Child year-olds year-olds year-olds Psychology, 87, 320–355. Does a causal relationship link these three observations? Perhaps the three are related in this fashion: Metamemory → Strategy use → Memory performance According to this argument, when children have poor metamemory, they will not be aware that they must use strategies to commit material to memory. If they do not use strategies, then their memory perfor- mance will be poor. We have some evidence that metamemory is related to strategy use. For example, children with sophis- ticated metamemory skills are more likely to report using memory strategies. They are also somewhat more likely to use these strategies effectively (e.g., Dunlosky & Metcalfe, 2009). In addition, we have extensive evidence to support the second link in the chain. As we’ve just seen, children’s strategy use is related to memory performance. So, metamemory is linked to strategy use, and strategy use is linked to memory performance. Is there a relationship between the two ends in that chain—that is, a relationship between metamemory and memory performance? Analysis of the research shows that the correlation between metamemory and memory per- formance is moderate (Ornstein et al., 2006; Schneider, 2002). It makes sense that the correlations are not stronger. One reason is that it’s difficult to test children’s metamemory, because they haven’t yet developed the sophisticated vocabulary necessary to describe their mental states (Joyner & Kurtz-Costes, 1997; Sodian, 2005). Furthermore, children may already know that memory strategies would be helpful, but they do not actually use them. After all, bright college students may have finely tuned metamemory skills; however, they may lack either the time or the motivation to actually use some potentially useful memory strategies. To some extent, elementary-school teachers can take advantage of “teachable moments” in the class- room, and they can help children understand how to think about improving their memory (Duffy et al., 2009; Grammer et al., 2011; Ornstein et al., 2011). Parents can also provide guidance. Furthermore, when parents reminisce with their young children, they provide a model that helps children understand how to think about future events (Laible & Panfile, 2009). 304 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN In summary, we can conclude that metamemory is moderately related to memory performance (Dunlosky & Metcalfe, 2009; Schneider, 2002). Consequently, the proposed causal sequence (Metamem- ory → Strategy use → Memory performance) could account for a substantial portion of the improvement in memory performance as children grow older. Metamemory in Elderly People What do elderly adults believe about their memory? Let’s begin by examining comparisons between older and younger adults in two areas: (1) their beliefs about how memory operates, and (2) their skill in moni- toring their memory. Then, let’s consider another topic: (3) whether elderly people are aware of their memory problems. Beliefs about Memory Older and younger adults share similar beliefs about the properties of memory tasks (Dunlosky & Metcalfe, 2009; Light, 1996). Both groups have the same fundamental knowledge about how memory works. They also have similar ideas about which strategies are most effective, and what kinds of material can be remembered most readily (Hertzog et al., 1999). Memory Monitoring On some tasks, older and younger adults are equally skilled in monitoring their memory performance (Bieman-Copland & Charness, 1994; Hertzog & Dixon, 1994). For example, the two groups are similar in their ability to predict—on an item-by-item basis—which items they can recall at a later time (Connor et al., 1997). Older and younger adults are also similar with respect to selecting the most difficult items for further study, rather than studying the items that they have already mastered (Dunlosky & Hertzog, 1997). The two groups also perform equally well in judging their accuracy when answering general-knowledge ques- tions and when deciding whether a particular item is old or new (Dodson et al., 2007). However, older adults are more likely than younger adults to be overconfident on some memory tasks (e.g., Dunlosky & Metcalfe, 2009). For example, Chad Dodson and his colleagues (2007) studied adults whose average age was 67 and college students whose average age was 21. The older adults were more likely than the young adults to overestimate their overall performance on a test of memory for specific details about a recent event. Furthermore, older adults are especially likely to overestimate their performance on a task where their working memory is “overworked” (Shake et al., 2009). In addition, older adults may be skilled in monitor- ing their memory, but then they may not use this information to decide how to remember some information (Krätzig & Arbuthnot, 2009). Finally, some older adults have dementia, a medical disorder that includes memory problems and other cognitive impairments (American Psychiatric Association, 2000). These individuals typically have difficulty in estimating their memory abilities (Youn et al., 2009). Awareness of Memory Problems The research about memory-problem awareness does not compare older and younger adults. Instead, it focuses on surveys of elderly individuals. Elderly people are likely to report problems with their everyday memory, especially on explicit recall tasks such as remembering names and phone numbers (Dunlosky & Metcalfe, 2009; Kester et al., 2002; Rendell et al., 2005). They are also likely to say that their memory fail- ures have increased over the years. Based on the research that we reviewed on explicit recall in elderly individuals, these reports may be accurate. The problem is that the popular stereotype about elderly people’s poor memory may encourage elderly individuals to think that memory decline is inevitable. As a result, many elderly people will not try to develop helpful memory strategies (Dunlosky & Metcalfe, 2009; Hess, 2005). In contrast, some elderly people are high in memory self-efficacy, which is a person’s belief in his or her own potential to perform well on memory tasks. They think that it’s important to keep developing their memory. As a result, they typically use effective memory strategies, and they perform relatively well (Dunlosky & Metcalfe, 2009; Zacks & Hasher, 2006). In summary, our examination of metamemory has revealed that elderly adults and young adults are similar in some respects (Dodson et al., 2007; Light, 2000). We saw earlier in this section that young The Development of Language 305 children’s metamemory is less accurate than young adults’ metamemory. In contrast, most elderly adults do not experience overwhelming metamemory impairments, and they remain quite competent on some metamemory tasks. The Development of Language “Mama!” (8 months old) “Wash hair.” (1 year, 4 months old) “Don’t tickle my tummy, Mommy!” (1 year, 11 months old) “My grandma gave me this dolly, Cara. My grandma is my mommy’s mommy. I have another grandma, too. She’s my daddy’s mommy. And Aunt Elli is my daddy’s sister.” (2 years, 9 months old) These selections from the early language of my daughter Sally are typical of children’s remarkable achievements during language acquisition. Individual children differ in the rate at which they master lan- guage (e.g., Fernald & Marchman, 2006; Hayne & Simcock, 2009; Tomasello, 2006). Still, within a period of 2–3 years, all typically developed children progress from one-word utterances to complex discourse. In fact, by the age of five, most children produce sentences that resemble adult speech (Kuhl, 2000). Many linguists say that language acquisition is the most spectacular of human accomplishments (Thompson & Madigan, 2005; Tomasello, 2006). Therefore, as you might expect, children’s linguistic skills clearly exemplify Theme 2. For instance, the average six-year-old can speak between about 10,000 and 14,000 words (MacWhinney, 2011). To acquire a vocabulary of this size, children must learn approxi- mately seven new words each day, from the time they start speaking until their sixth birthday (Carroll, 2008; Wellman, 2000). If you are not impressed by a 14,000-word vocabulary, consider how much effort high school students must exert to learn 1,000 words in another language—and those six-year-old lan- guage learners are only waist-high! However, language acquisition includes much more than the simple acquisition of new words. For example, children combine these words into phrases that they have never heard before, such as, “My dolly dreamed about toys” (2 years, 2 months). Researchers have typically ignored developmental and learning-based changes in language during late adulthood, although some research is emerging (e.g., de Bot & Makoni, 2005; Fine et al., 2013; Kamide, 2012; Kemper, 2006; Stine-Morrow et al., 2006; Whitbourne & Whitbourne, 2011). Our discussion of language development is therefore limited to infancy and childhood. Language in Infants During the first 18 months of life—and even shortly before birth—human infants are preparing to use lan- guage (Curtin & Werker, 2009). Let’s begin by considering how young infants perceive the basic sounds of speech. Then, we look at several early skills in language comprehension and language production. We also see that adults provide infants with a very helpful kind of language, which clearly helps them acquire language. Our last topic in this part of the chapter focuses on a question from applied psychology: Can infants learn language by watching a popular DVD? Speech Perception during Infancy To acquire language, infants must be able to distinguish between phonemes, which are the smallest sound units in a language. However, the ability to make distinctions is only half of the struggle. Infants must also be able to group together the sounds that are phonetically equivalent. For example, infants must be able to recognize that the sounds b and p are different from each other. In addition, they must recognize that the sound b, spoken by the deepest bass voice, is the same as the sound b, spoken by the highest soprano voice (Harley, 2008; Jusczyk & Luce, 2002; Saffran et al., 2006). If you have recently observed a baby who is younger than six months old, you might have concluded that the baby’s mastery of language was roughly equivalent to the linguistic skills of your elbow. Until the early 1970s, psychologists were not much more optimistic. However, more than 40 years of research have demonstrated that infants’ speech perception is surprisingly advanced (Fennell, 2012). Infants can per- ceive almost all the speech-sound contrasts used in language, either at birth or within the first few weeks of life (Houston, 2005; Todd et al., 2006; Werker & Tees, 1984). They can also recognize similarities, an 306 COGNITIVE DEVELOPMENT THROUGHOUT THE LIFESPAN important early stage in language comprehension. Young infants’ abilities clearly encourage them to learn languages (Curtin & Werker, 2009; Jusczyk & Aslin, 1995; Saffran et al., 2006; Traxler, 2012). In some cases, young infants are even more skilled than older infants and adults in making phonemic distinctions (Curtin & Werker, 2009). For example, Hindi is a language spoken in India. In Hindi, the t sound is sometimes made by placing the tongue against the back of the teeth. However, the t sound can also be made by placing the tongue farther back along the roof of the mouth. Hindi speakers can easily distinguish between these two sounds in their language. As it happens, however, English-speaking adults cannot distinguish between these two t sounds. Do the children of English speakers tend to be more skilled? Werker and Tees (1984) tested infants who were being raised in an English-speaking environment. Impressively, infants could distinguish between these two Hindi phonemes with about 95% accuracy when they are 6–8 months old. Their accuracy drops to about 70% at 8–10 months of age, and to about 20% at 10 to 12 months of age. In contrast, consider 10- to 12-month-old infants who have been raised in a Hindi-speaking environment. These infants distinguish between these two phonemes with close to 100% accuracy (Werker &Tees, 1984). Apparently, young infants can appreciate numerous phonetic distinctions in every language. Later, however, they reorganize their perceptual categories so that they focus on the important distinctions from their own language environment (Curtin & Werker, 2009; Lany & Saffran, 2010; MacWhinney, 2011; Todd et al., 2006). According to other research on speech perception, newborns can discriminate between two languages that have different rhythms, such as English and Italian (Saffran et al., 2006). Furthermore, research by Bosch and Sebastián-Gallés (2001) focused on children being raised in bilingual homes where the parents spoke two rhythmically similar languages, Spanish and Catalan (Catalan is a language spoken in Barce- lona, Spain, and the surrounding region). Impressively, 4-month-olds could discriminate between these two languages! These discrimination skills help infants to keep these two languages from being confused with each other (Curtin & Werker, 2009; Saffran et al., 2006). Language Comprehension during Infancy The research about speech perception in infancy has been active for several decades. In contrast, researchers have been slower to explore how infants master the more complex aspects of language comprehension, beyond the level of the phoneme. However, we now have information about young infants’ comprehension skills in several areas: (1) recognizing important words, (2) understanding the correspondence between a speaker’s facial expression and the emotional tone of the speaker’s voice, and (3) appreciating semantic concepts. 1. Recognizing important words. Interestingly, infants between the ages of four and five months can already recognize the sound patterns in their own name. Specifically, Mandel and her colleagues (1995) found that infants are likely to turn their heads to look at a location from which their own name is spoken. In contrast, they seldom turn their heads when a different name is spoken that is similar in length and accented syllable (e.g., Megan for an infant named Rachel). Young infants can also understand a few selected words (Curtin & Werker, 2009; Piotroski & Naigles, 2012; Saffran et al., 2006). For example, Tincoff and Jusczyk (1999) showed each 6-month-old two videos placed next to each other. One video showed the infant’s mother, and the other showed the infant’s father. Meanwhile, the infants heard either the word mommy or the word daddy. When mommy was presented, the infants preferred to look at the video of their mother. When daddy was presented, they preferred to look at the video of their father. 2. Understanding the correspondence between sound and sight. Infants also appreciate another component of language comprehension: the emotional tone of spoken language (Flavell et al., 2002). For example, Walker-Andrews (1986) played recordings of either a happy voice or an angry voice to seven-month-old infants. Meanwhile, the infants saw a pair of films—one of a happy speaker and one of an angry speaker—projected side-by-side. The mouth region of each face was covered so that the infants could not rely on lip movements to match the voice with the film. Therefore, the infants had to look for emotional cues only in the speaker’s cheeks and eyes, rather than in the most obvious location, the speaker’s mouth. The results of Walker-Andrews’s (1986) study showed that infants who heard a happy voice watched the happy face more often. In contrast, the infants who heard an angry voice watched the angry face more often. In other words, even young infants appreciate that facial expression must correspond with vocal intonation. The Development of Language 307 3. Appreciating semantic concepts. So far, we’ve seen that infants respond when they hear their own names. They also link the words “mommy” and “daddy” with the visual image of the appropriate parent. In addition, they know that sight and sound must be linked together. According to research by Jean Mandler and her colleagues, infants also show remarkable skills when we consider their concepts about objects. For example, by about nine months of age, infants can distin- guish between animate objects, which move by themselves, and inanimate objects, which cannot move independently (Mandler, 2003, 2004a, 2007). In another study, McDonough and Mandler (1998) showed nine-month-old infants a dog drinking from a cup and a car giving a doll a ride. The researchers then handed the infants some new objects from two categories—such as a cat and an anteater for the animal category and a truck and a forklift for the vehicle category. The infants showed the appropriate imitation patterns for the new objects, even for the relatively unfamiliar ones. For example, they showed the anteater drinking, whereas they showed the forklift giving the doll a ride. Infants therefore have the ability to generalize across a category such as “animal” or “vehi- cle” (Mandler, 2003, 2004a). In other words, children can understand concepts before they are 1-year old (Mandler, 2007). As children mature, their categories become more refined. For example, 14-month-old children watched a researcher give a toy dog a drink from a cup. Then, the researcher handed the cup to a child, together with a different dog, a cat, an unfamiliar mammal, and a bird. Children typically gave the cup to all three mammals, but not to the bird (Mandler, 2004a, 2004b). By their actions, young children reveal their sophisticated knowledge about categories: “Land animals can drink from a cup, but birds cannot” (Mandler, 2007). Chapter 8 emphasized that your conceptual ability allows you to categorize similar objects together and to make inferences based on these categories. As we’ve just seen, this skill begins to develop before a child’s first birthday. The word “infant” originally meant “not capable of speech” (Pan, 2012). In a moment, you will see that the language production of young infants is definitely limited. However, their speech per- ception and language comprehension are impressively sophisticated, even when they are only a few months old. Language Production during Infancy The early vocalizations of infants pass through a series of stages. By about two months of age, infants begin to make cooing noises, sounds that involve vowels such as oo. By about six months th