CHAPTER 2

Critiquing vygotskys theory

Vygotsky focused more on the processes through which children develop than on the characteristics that children of particular ages are likely to exhibit. He described stages of development, but portrayed them in only the most general terms (e.g., see Vygotsky, 1997, pp. 214-216). In addition, Vygotsky's descriptions of developmental processes were often vague and speculative (Gauvain, 2001; Haenan, 1996; Moran & John-Steiner, 2003). For such reasons, Vygotsky's theory has been difficult for researchers to test and either verify or disprove. Nevertheless, contemporary theorists and educators have found Vygotsky's ideas insightful and helpful (Portes & Salas, 2011; Smagorinski, 2013). Most significantly, his theory points out the many ways in which culture influences cognitive development. A society's culture ensures that each new generation benefits from the accumulating wisdom of preceding generations. Any culture guides children in certain directions by encouraging them to pay attention to particular stimuli (and not to others) and to engage in particular activities (and not in others). In addition, it provides a lens through which children come to view and interpret their experiences in culturally appropriate ways. We see obvious effects of culture in many of children's everyday activities—in the books they read, the roles they enact in pretend play, the extracurricular activities they pursue—but we must remember that culture permeates their unobservable thinking processes as well. When children come to school, keep in mind that from a Vygotskian perspective, their thought processes have been shaped by their cultures. Thus, some students may experience difficulties at school because their thought processes have been shaped by interactions and traditions that may not be aligned with the practices of the school in which you teach. Furthermore, some research has supported Vygotsky's views regarding the progression and role of self-talk and inner speech. The frequency of children's audible self-talk decreases during the preschool and early elementary years, but this decrease is at first accompanied by an increase in whispered mumbling and silent lip movements, presumably reflecting a transition to inner speech (Bivens & Berk, 1990; Winsler & Naglieri, 2003). Self-talk increases when children are performing more challenging tasks, at which they must exert considerable effort to be successful (Berk, 1994; Schimmoeller, 1998). As you undoubtedly know from your own experience, even adults occasionally talk to themselves when they face new challenges. Self-talk can be particularly beneficial in sports—adults and adolescents who engage in positive self-talk can actually enhance their performance! (Tod, Hardy, & Oliver, 2011)

Considering diversity from the perspective of vygotksys theory

Vygotsky's theory leads us to expect greater diversity in cognitive development among children and adolescents than Piaget's theory does. As we've seen, children in any single age group are apt to have different zones of proximal development: Tasks that are easy for some children may be quite challenging or virtually impossible for others. In addition, to the extent that specific cultural groups pass along unique concepts, ideas, and beliefs, children from different cultural backgrounds will acquire somewhat different knowledge, skills, and ways of thinking. For instance, children are more likely to acquire map-reading skills if they regularly encounter maps (e.g., of roads, subway systems, shopping malls) in their community and family life (Liben & Myers, 2007).

Language development

Acquiring the language of one's culture is an extremely complex and challenging undertaking. To understand and use a language effectively, children must master four basic components of the language. First, they must master their language's phonology: They must know how words sound and be able to produce the sequence of sounds that make up any given word. Second, they must master semantics, the meanings of many thousands of words. Third, they must have a good command of syntax, knowing how words can legitimately be combined to form understandable phrases and sentences. And finally, children must master the pragmatics of their language—the social conventions and speaking strategies that enable effective communication with others. Mastering these four components of language is a remarkable achievement for any child, yet before children reach kindergarten, most of them have acquired sufficient proficiency in language to carry on productive conversations with the people around them. Their language development continues throughout childhood and adolescence, in part as a result of informal social interactions and in part as a result of formal instruction (see Table 2.2). Some aspects of language development during the school years reflect an increasing ability to think abstractly about physical and social phenomena. For example, abstract thought enables children to reflect, deliberately and consciously, on the general nature and functions of language—an acquisition known as metalinguistic awareness (Owens, 2008; Yaden & Templeton, 1986). With such awareness comes an ability to recognize the figurative nature of words—the nonliteral meanings of proverbs, the symbolism in poems and literature, and so on. At the same time, children's ever-expanding language capabilities probably also help them think abstractly (K. Nelson, 1996; Pinker, 2007), and they become better able to write stories, poems, and nonfiction

Second language learning and english language learners

As mentioned earlier, exposure to a second language in childhood or early adolescence may be especially important for acquiring flawless pronunciation and certain aspects of syntax. Early exposure to a second language seems to be most advantageous if the second language is very different from the first. For example, a native English speaker benefits more from an early start in Arabic or Navajo than from an early start in, say, Spanish or German (Bialystok, 1994; Strozer, 1994). Aside from such caveats, there appears to be no definitive "best" time to begin studying a second language (e.g., P. K. Kuhl et al., 2005; G. Stevens, 2004). Yet beginning second-language instruction in the early years has other noteworthy advantages. For one thing, it appears that learning a second language facilitates achievement in other academic areas such as reading, vocabulary, and grammar (Diaz, 1983; Reich, 1986). Instruction in a foreign language also sensitizes young children to the international and multicultural nature of the world. Students who learn a second language during the elementary school years express more positive attitudes toward people who speak that language and are more likely to enroll in foreign language classes in high school (Reich, 1986

Piaget's proposed stages of cognitive development

As mentioned earlier, some developmental theorists argue that development occurs in predictable stages, and that these stages can be described in terms of specific developmental milestones. Piaget's theory is one such stage theory. Piaget proposed that as a result of brain maturation, experiences in children's physical and social environments, and children's natural desire to make sense of and adapt to their world, cognitive development proceeds through four distinct stages, with the last three being constructed from children's accomplishments in the preceding stages (e.g., Piaget, 1971). Thus, the stages are hierarchical—each stage provides a foundation for any subsequent ones—and so children progress through them in a specific order. Table 2.1 summarizes Piaget's four stages and presents examples of abilities acquired during each one. As you look at the table, please keep three things in mind: First, as children transition from one stage to the next, they may display characteristics of two adjacent stages at the same time. Second, as children gain abilities associated with the more advanced stages, they don't necessarily leave behind the characteristics they acquired in previous stages. Finally, many researchers—including Piaget himself—suggest that the four stages better describe how children and adolescents can think, rather than how they always do think, at any particular age (Flavell, 1994; Halford & Andrews, 2006; Klaczynski, 2001; Tanner & Inhelder, 1960). The preoperational, concrete operations, and formal operations stages all occur during the school years, and so we'll look at these three stages more closely Preoperational Stage (Age 2 Through Age 6 Or 7) In the early part of the preoperational stage, children's language skills virtually explode, and the many words in their rapidly increasing vocabularies serve as symbols that enable them to mentally represent and think about a wide variety of objects and events. However, preoperational thought has some definite limitations, especially when compared to the concrete operational thinking that emerges later. For example, Piaget described young children as exhibiting preoperational egocentrism: They don't yet have sufficient reasoning abilities to look at a situation as someone else might look at it. Thus, preschoolers might play games together without checking to be sure they're all playing by the same rules. Young children's thinking also tends to be somewhat illogical at times, at least from an adult's point of view. We've already seen how young children have difficulty with class inclusion problems (recall Brian's insistence that the brown beads outnumber the wooden ones). In addition, they're apt to have trouble with conservation: They fail to realize that if nothing is added or taken away, the amount of a substance or set of objects must stay the same regardless of changes in appearance. As illustrations, consider what happens when we present two conservation tasks to 5-year-old Nathan: Conservation of liquid: We show Nathan the three glasses in Figure 2.3. We ask him whether Glass A and B contain the same amount of water, and he replies confidently that they do. We then pour the water from Glass B into Glass C and ask him whether Glass A and Glass C have the same amount. Nathan replies, "No, that glass [pointing to Glass A] has more because it's taller." Conservation of number: We next show Nathan two rows of seven pennies each, like so: Nathan counts the pennies in each row and agrees that the two rows have the same amount. We spread the second row out, and the pennies now look like this: When we ask Nathan whether the two rows still have the same number, he replies, "No, this one [pointing to the bottom row] has more because it's longer. As children approach the later part of the preoperational stage, perhaps at around age 4 or 5, they show early signs of adult-like logic. For example, they sometimes draw correct conclusions about class inclusion and conservation problems. But they often base their reasoning on hunches and intuition, rather than on any conscious awareness of underlying logical principles, and thus they can't yet explain why their conclusions are correct.

General principles of huamn development

As teachers, we need to always be aware that although the students in our classrooms may be similar to each other in age, they nevertheless can be at very different places in terms of their readiness to learn and their skills at interacting with others. This chapter focuses on cognitive development, and the next chapter focuses on social aspects of development. There are actually four general principles that characterize all aspects of children's development (i.e., physical, cognitive, personal, and social development). • The sequence of development is somewhat predictable. Children tend to develop in predictable ways. Although children live in diverse environments and cultures, the order in which they demonstrate developmental accomplishments generally will be the same. As children grow older, they reach various developmental milestones— new, developmentally more advanced behaviors—in predictable sequences. For example, children must be able to walk before they can run and jump, and they must be able to count and work with whole numbers before they become capable of understanding fractions. • Children develop at different rates. Not all children reach particular milestones at the same age; some reach them earlier, some later. Accordingly, we are likely to see considerable diversity in students' developmental accomplishments at any single grade level. As teachers, we should never jump to conclusions about what individual students can and cannot do based on age alone. For example, some students in Mrs. Bennington's class appear to be able to understand that objects can sometimes be classified in several ways (e.g., as both a plant and a food), whereas this concept may be a bit too advanced for other students. • Development is often marked by periods of relatively rapid growth (spurts) between periods of slower growth (plateaus). Development doesn't necessarily proceed at a constant rate. For example, toddlers may speak with a limited vocabulary and one-word "sentences" for several months, yet sometime around their second birthday their vocabulary expands rapidly and their sentences become increasingly longer within just a few weeks. And after seemingly stalling out height-wise, many young adolescents undergo a growth spurt, shooting up several inches within a year or so. Occasionally, children even take a temporary step backward in development, apparently because they're in the process of revamping a particular physical or cognitive skill and are about to make a major leap forward (Gershkoff-Stowe & Thelen, 2004; Morra, Gobbo, Marini, & Sheese, 2008). • Some researchers have suggested that such patterns of uneven growth reflect distinctly different periods, or stages, in development; you'll see an example in the discussion of Piaget's theory later in this chapter. Other researchers believe that most aspects of development can best be characterized as reflecting general trends that can't really be broken into discrete stages. Either way, early developmental advancements almost certainly provide a foundation on which later advancements can build—hence the predictable this-before-that nature of many developmental progressions. • Heredity and environment interact in their effects on development. Many aspects of development are influenced either directly or indirectly by a child's genetic makeup. For example, soon after birth, children begin to show genetic inclinations, or temperaments, that predispose them to respond to physical and social events in certain ways—perhaps to be calm or irritable, outgoing or shy, cheerful or fearful. Not all inherited characteristics appear so early, however. Heredity continues to guide a child's growth through maturation—a gradual, genetically driven acquisition of more advanced physical and neurological capabilities that affect both cognitive and social aspects of development over the course of childhood and adolescence. For example, motor skills, such as walking, running, and jumping, develop primarily as a result of neurological development, increased strength, and increased muscular control—changes that are largely determined by inherited biological "instructions." Yet environmental factors also make substantial contributions to development. For example, although height and body build are primarily inherited characteristics, good nutrition and regular physical exercise also make a difference. And although children's behaviors and social interactions are partly the result of inherited temperaments, the ways in which their environment encourages them to behave are just as influential; sometimes even more so. For example, research clearly indicates that the quality of both in-home and preschool experiences can affect children's language and cognitive development (Hall et al., 2013; Justice, Jiang, Khan, & Dynia, 2017; Lin, Justice, Paul, & Mashburn, 2016; Logan, Piasta, Justice, Schatschneider, & Petrill, 2011; Votruba-Drzal, Coley, Koury, & Miller, 2013). When children attend high-quality preschools (e.g., schools in which the teachers actively use strategies that promote children's conceptual and linguistic development), language and literacy skills in particular increase.

Multiple layers of enviornmnet influnce: Bioecological systems and the importance of culture

As we consider the various ways in which the environment might influence children's development, we must be careful that we don't limit our thinking only to children's immediate surroundings. In fact, as developmental theorist Urie Bronfenbrenner has pointed out in his bioecological systems theory, any large society encompasses several "layers" of environment that all have significant impacts on children's development and are, in turn, either directly or indirectly influenced by the other layers and by the children themselves (Bronfenbrenner, 2005; Bronfenbrenner & Ceci, 1994; Bronfenbrenner & Morris, 1998). Figure 2.1 depicts the various layers of influence that Bronfenbrenner has proposed. More specifically: 1. The child brings certain characteristics (e.g., unique temperaments and physiological features) and age-related developmental acquisitions (e.g., cognitive abilities and interpersonal skills) that influence the child's behaviors in any given situation. 2. The child is regularly immersed in certain microsystems—everyday contexts (e.g., family, school, friendships) that both influence and are influenced by the child's characteristics and behaviors. 3. The microsystems in which a child lives and grows influence one another in what Bronfenbrenner has called a mesosystem. For example, a temperamentally hyperactive child might initially elicit stringent disciplinary actions at school (one microsystem), but concerned parents (another microsystem) might actively seek out the child's teachers and suggest alternative strategies that can channel the child's behaviors into productive activities. 4. Encompassing the day-to-day contexts in which a child lives, works, and plays is a broader exosystem, which includes people and institutions that indirectly affect the child's development through their influences on various microsystems. For example, the nature of parents' employment can affect their ability to provide adequate living quarters, nutrition, and health care for their family, and a good social support network can provide parents with advice, assistance, and emotional support in challenging circumstances. Meanwhile, local and federal agencies and policies may influence teachers' and schools' ability to nurture children's cognitive development and social well-being. 5. A child's exosystem is enmeshed within an even broader macrosystem, which includes a society's general beliefs, ideological perspectives, and behavior patterns, as well as far-reaching current events (e.g., war, migration patterns, ongoing social or political strife). 6. Children and the systems in which they grow up all change over time—in part because they influence one another—in what Bronfenbrenner has called a chronosystem (see the bottom set of arrows in Figure 2.1). For example, teachers' instructional practices might change as academic researchers report new research findings, government agencies might provide websites that help parents and teachers more effectively foster children's cognitive development, and society's general beliefs and practices can change as two or more subgroups regularly interact. In general, children's environments are dynamic systems encompassing mutually influencing variables that are in constant flux (also see C. D. Lee, 2010; Perone & Simmering, 2017; Thelen & Smith, 1998). It has become increasingly clear that a key factor affecting all of these systems is a child's culture—the behaviors and belief systems that characterize any longstanding social group of which the child is a member. Culture is pervasive in many aspects of a child's home environment—for instance, in the behaviors parents and other family members encourage, the disciplinary practices parents use, the books children have access to, the television shows they watch, the social media that they engage with, and so on. Culture influences broader environmental contexts as well—for instance, by offering certain outlets for leisure time (e.g., basketball courts, cultural celebrations such as Cinco de Mayo or Chinese New Year celebrations), and by advocating or discouraging certain activities (e.g., seeking a college degree, getting a part-time job, participating in school athletic teams). Ultimately, culture is an inside-the-head thing as well as an out-there-in-the-world thing: It provides an overall framework by which a child comes to determine what things are normal and abnormal, true and not true, rational and irrational, good and bad (M. Cole, 2006; Shweder et al., 1998).

Contempory extensions and applications of vygotksys theory

The Into the Classroom feature "Applying Vygotsky's Theory" presents concrete examples of how teachers might make use of Vygotsky's ideas. In the upcoming sections, we'll consider several ways in which contemporary theorists and educators have built on the foundations that Vygotsky laid. Social Construction of Meaning Contemporary psychologists have elaborated on Vygotsky's proposal that adults help children attach meanings to the objects and events around them. Often, an adult will help a child make sense of the world through a joint discussion of a phenomenon or event they are both experiencing (Feuerstein, Feuerstein, & Falik, 2010; P. K. Murphy, Wilkinson, & Soter, 2011). Such an interaction, sometimes called a mediated learning experience, encourages the child to think about the phenomenon or event in particular ways—to attach labels to it, recognize principles that underlie it, draw certain conclusions from it, and so on. As an example, consider the following exchange, in which a 5-year-old boy and his mother are talking about a prehistoric animal exhibit at a natural history museum. Even without his mother's assistance, the boy would almost certainly have learned something about saber-tooth tigers from his museum visit. Yet Mom helps him make better sense of what he is looking at than he might have done on his own—for instance, by using the label saber tooth and helping him connect tooth characteristics to eating preferences. Notice how persistent Mom is in asking her son to make the tooth-food connection: She continues to ask him about meat versus plants until the boy finally correctly infers that the tigers must have been meat eaters. In addition to co-constructing meanings with adults, children and adolescents often talk among themselves to make sense of their experiences. School provides an ideal setting in which young people can toss around ideas and perhaps reach consensus about how best to interpret and understand a complex issue or problem—perhaps about a challenging math problem, troubling interpersonal dynamics with peers, or about moral dilemmas with no easy right or wrong answers. Interacting with adults and interacting with peers possibly play somewhat different roles in children's development. Adults usually have more experience and expertise than age-mates do, and they tend to be more skillful teachers. Accordingly, adults are often the partners of choice when children are trying to master complex new tasks and procedures (Gauvain, 2001; Radziszewska & Rogoff, 1988). Working with peers has a different set of advantages. First, as mentioned in the earlier discussion of Piaget's theory, children who hear age-mates express perspectives quite different from their own may experience sociocognitive conflict that motivates them to reassess their own understandings. Second, as Vygotsky suggested, peer interactions provide a social context in which children practice and eventually internalize complex cognitive processes, such as effective reading comprehension and argumentation skills (Andriessen, 2006; Chinn, Anderson, & Waggoner, 2001; P. K. Murphy et al., 2011). A third benefit is that children learn valuable social behaviors—including how to plan a collaborative project and how to coordinate differing roles—when they work on cognitive tasks with their peers (Gauvain, 2001).

Role of the brain in learning and development

One key player in children's cognitive development is, of course, the brain. The human brain is an incredibly complicated organ that includes several trillion cells. About 100 billion of them are nerve cells, or neurons, that are microscopic in size and interconnected. Some neurons receive information from the rest of the body, others synthesize and interpret that information, and still others send messages that tell the body how to respond to its present circumstances. Accompanying neurons are perhaps 1 trillion to 5 trillion glial cells, which serve a variety of specialized functions and surround the neurons. Every neuron has numerous branchlike structures, called dendrites, that receive messages from other neurons (see Figure 2.2). Every neuron also has an axon, a long, armlike structure that transmits information on to still other neurons. The axon may branch out many times, and the ends of its branches have terminal buttons that contain certain chemical substances. For some (but not all) neurons, much of the axon has a white, fatty coating called a myelin sheath. When a neuron's dendrites are stimulated by other neurons—which might also be in the brain or, instead, might extend from other parts of the body—the dendrites become electrically charged. If the charge reaches a certain level, the neuron fires, sending an electrical impulse along its axon to the terminal buttons. If the axon has a myelin sheath, the impulse travels quite rapidly because it leaps from one gap in the myelin to the next, almost as if it were playing leapfrog. If the axon doesn't have a myelin sheath, the impulse travels more slowly. Neurons don't actually touch one another. Instead, they send chemical messages to their neighbors across tiny spaces known as synapses. When an electrical impulse moves along a neuron's axon, it signals the terminal buttons to release chemicals known as neurotransmitters that travel across the synapses and stimulate neighboring neurons. Any single neuron may have synaptic connections with hundreds or even thousands of other neurons (Goodman & Tessier-Lavigne, 1997; Lichtman, 2001). With these basics in mind, let's consider four key points about the brain and its role in cognitive development. • Different parts of the brain have different specialties, but they all work closely with one another. Brain structures in the lower and middle parts of the brain specialize in essential physiological processes (e.g., breathing), habitual body movements (e.g., riding a bicycle), and basic perceptual skills (e.g., diverting attention to potentially life-threatening stimuli). Complex, conscious thinking takes place primarily in the cortex, which rests on the top and sides of the brain like a thick, lumpy toupee. The part of the cortex located just behind the forehead, known as the prefrontal cortex, is largely responsible for a wide variety of very human activities, including sustained attention, planning, reasoning, decision making, coordination of complex activities, creativity, and inhibition of nonproductive thoughts and behaviors. Other areas of the cortex are actively involved in interpreting visual and auditory information, identifying the spatial characteristics of objects and events, and retaining general knowledge about the world. To some degree, the left and right halves of the cortex—its two hemispheres— also have somewhat distinct specialties. For most people, the left hemisphere takes primary responsibility for language and logical thinking, whereas the right hemisphere is more dominant in visual and spatial tasks (Byrnes, 2001; Ornstein, 1997; Siegel, 2012). Yet contrary to a popular belief, people rarely, if ever, think exclusively in one hemisphere. There's really no such thing as "left-brain" or "right-brain" thinking: The two hemispheres constantly collaborate in day-to-day tasks. In fact, learning or thinking about virtually anything, even a fairly simple idea, tends to be distributed across many parts of the brain (Bressler, 2002; Gonsalves & Cohen, 2010; Haxby et al., 2001). • Learning and cognitive development involve changes in synapses, neurons, and glial cells. Much of human learning involves strengthening existing synapses between neurons, or forming new ones. Sometimes, however, making progress actually involves eliminating synapses. Effective learning requires not only that people think and do certain things but also that they not think and do other things—in other words, that they inhibit tendencies to think or behave in particular ways (C. N. Davidson, 2011; Lichtman, 2001; Merzenich, 2001). In addition, a good deal of learning seems to involve the formation of new neurons or glial cells (Koob, 2009; Spalding et al., 2013). Brain-imaging studies suggest that there is a positive correlation between the density of connections between various brain regions and traditionally measured intelligence (Seidlitz et al., 2017). • Developmental changes in the brain enable increasingly complex and efficient thought. Neurons begin to form synapses long before a child is born. But shortly after birth, the rate of synapse formation increases dramatically. Neurons sprout new dendrites in many directions, and so they come into contact with a lot of their neighbors, especially in the first 2 or 3 years of life. Much of this early synaptogenesis appears to be driven primarily by genetic programming rather than by learning experiences. Thanks to synaptogenesis, children in the elementary grades have many more synapses than adults do (Bruer, 1999; C. A. Nelson, Thomas, & de Haan, 2006). As children encounter different stimuli and experiences in their daily lives, some synapses come in quite handy and are used repeatedly; others are largely useless, and these gradually fade away through another genetically driven process known as synaptic pruning. This process continues throughout the elementary and secondary school years and into adulthood. Most synaptic pruning is a good thing— not a bad one—because it eliminates "nuisance" synapses that are inconsistent MyLab Education Video Explanation 2.1 In this short video, you can learn a little more about basic structures in the brain. M02_ORMR6478_10_SE_C02.indd 26 07/11/2018 12:09 Cognitive and Linguistic Development 27 with typical environmental events and appropriate responses. Synaptic pruning, then, may be Mother Nature's way of making the brain more efficient (Bruer & Greenough, 2001; Bryck & Fisher, 2012; Huttenlocher & Dabholkar, 1997). Another important developmental process in the brain is myelination. When neurons first develop, their axons have no myelin sheath. As they acquire this myelin over time, they fire much more quickly, greatly enhancing the brain's overall efficiency. Myelination continues throughout childhood, adolescence, and early adulthood, especially in the cortex (Giedd et al., 2012; Merzenich, 2001; Paus et al., 1999). In addition, the onset of puberty is marked by significant changes in hormone levels, which affect the continuing maturation of brain structures and possibly also affect the production and effectiveness of neurotransmitters (Kolb, Gibb, & Robinson, 2003; Shen et al., 2010; E. F. Walker, 2002). Such changes can have an effect on adolescents' functioning in a variety of areas, including attention, planning, and impulse control. To some degree, adolescents' abilities to learn and respond appropriately may temporarily decrease until brain functioning restabilizes (McGivern, Andersen, Byrd, Mutter, & Reilly, 2002; Shen et al., 2010; Steinberg, 2009). • The brain remains adaptable throughout life. Some aspects of cognitive development appear to have sensitive periods in which certain kinds of environmental stimulation are crucial. For example, if infants don't have normal exposure to patterns of light (e.g., if congenital cataracts make them functionally blind), they may soon lose the ability to see normally. And if children don't hear spoken language in the first few years of life, they're apt to have trouble mastering some of its complexities once they do begin to hear it (more about this point later in the chapter). However, seeing patterned light and hearing spoken language are normal experiences, not exceptional ones. There is no evidence to indicate that sensitive periods exist for traditional academic subjects such as reading and mathematics From a physiological standpoint, the brain's ability to reorganize itself in order to adapt to changing circumstances—that is, its plasticity—persists throughout the lifespan (Chein & Schneider, 2012; Kolb et al., 2003; C. A. Nelson et al., 2006). The early years are important for development, to be sure, but so are the later years. For most topics and skills, there isn't a single "best" or "only" time to learn (Bruer, 1999; Byrnes & Fox, 1998; Geary, 1998, 2008). The human brain never goes into lockdown mode. As researchers gradually pin down how the brain works and develops, they're also beginning to get clues about how we can best foster children's and adolescents' cognitive development; three research-based recommendations are presented in the Applying Brain Research feature "Taking Developmental Changes in the Brain into Account." Even so, current knowledge of brain physiology doesn't yield many specifics about how best to foster students' learning and cognitive development (Anderson, 2014; Byrnes, 2007; G. A. Miller, 2010; Varma, McCandliss, & Schwartz, 2008). If we want to understand the nature of human learning and cognitive development, we must look primarily at what psychologists, rather than neurologists, have discovered. Two early theories—those of Jean Piaget and Lev Vygotsky—have been especially influential in molding contemporary views of how children learn and develop

Considering diversity from the perspective of piaget's theory

As a researcher working in Switzerland, Piaget conducted his studies with a particular population: Swiss children. However, the course of cognitive development appears to vary somewhat from one cultural group to another, probably because different cultures provide somewhat different experiences (Liu, Wellman, Tardiff, & Sabbagh, 2008). For example, Mexican children who have had considerable experience in hand-weaving complex flower, animal, and geometric designs show preoperational and concrete operational abilities in new weaving problems sooner than do their same-age counterparts in the United States; the difference remains even if the U.S. children are given explicit training in the Mexican weaving techniques (Maynard & Greenfield, 2003). And Mexican children whose families make pottery for a living acquire conservation skills earlier than their peers in other Mexican families, probably because making pottery requires children to make frequent judgments about needed quantities of clay regardless of the clay's shape (Price-Williams, Gordon, & Ramirez, 1969). Formal operational reasoning skills—for example, reasoning about hypothetical ideas and separating and controlling variables—also vary from culture to culture (Flieller, 1999; Norenzayan, Choi, & Peng, 2007; Rogoff, 2003). Mainstream Western culture actively nurtures these skills through formal instruction in such academic content domains as science, mathematics, literature, and social studies. In some other cultures, however, such skills may have little relevance to people's daily lives (M. Cole, 1990; J. G. Miller, 1997; Norenzayan et al., 2007). Even within a single cultural group, logical reasoning abilities vary considerably from one individual to another, in part as a result of differences in background knowledge about particular topics. For example, adolescents (adults, too) often apply formal operational thought to topics about which they know a great deal, yet think concretely about topics with which they're unfamiliar (Girotto & Light, 1993; M. C. Linn, Clement, Pulos, & Sullivan, 1989; Schliemann & Carraher, 1993). As an illustration, in a study by Pulos and Linn (1981), 13-year-olds were shown a picture similar to the one in Figure 2.6 and told, "These four children go fishing every week, and one child, Herb, always catches the most fish. The other children wonder why." If you look at the picture, you can see that Herb differs from the other children in several ways, including his location, the bait he uses, and the length of his fishing rod. Students who had fished a great deal separated and controlled variables more effectively for this situation than they did for the pendulum problem presented earlier, whereas the reverse was true for students with little or no fishing experience. Moreover, experiences with diversity can enhance cognitive development, particularly among older adolescents. Many colleges offer coursework and workshops focusing on diversity, and these do promote critical, abstract thinking; however, social interactions among students with racially diverse peers may be particularly helpful in this regard (Bowman, 2010; Page, 2017).

Contrasting piaget's and vygotsky's theories

Both Piaget and Vygotsky have had a profound influence on contemporary views of learning, thinking, and cognitive development. If we look beyond their differing terminologies, we can see some common themes in the two perspectives. First, both theorists suggested that children acquire increasingly complex thinking processes with age and experience. Second, both argued for the importance of challenge, perhaps in the form of puzzling new information (Piaget's disequilibrium) or perhaps in the form of tasks that can be completed only with another person's support (Vygotsky's zone of proximal development). And third, at any given point in development, children are cognitively ready for some experiences but not for others. In Piaget's view, a child can accommodate to new objects and events only when the child can, to some degree, also assimilate them into existing schemes—that is, there must be some overlap between the "new" and the "old." From Vygotsky's perspective, some challenging new tasks may fall within a child's ZPD—and thus be accomplishable with guidance and support—but other tasks are likely to be out of reach for the time being. Nevertheless, Piaget's and Vygotsky's theories differ in significant ways. For one thing, Piaget maintained that children's cognitive development is largely the result of their own efforts—for instance, their informal experiments with physical objects and their attempts to restore equilibrium in the face of puzzling events. In contrast, Vygotsky placed considerable emphasis on the role of adults and other, more advanced individuals, who can mediate new experiences and provide needed support during challenging activities. The difference, then, is one of self-exploration and discovery (Piaget) versus guided exploration and instruction (Vygotsky). A second key difference lies in the potential influence of the culture in which children grow up. Piaget recognized that cultural differences might have an effect, but he didn't systematically consider them in children's thinking processes. In Vygotsky's theory, however, culture is of paramount importance in molding the specific thinking skills children acquire—a perspective that Bronfenbrenner echoed in describing the multiple layers of environmental influence on children's development. Increasingly, contemporary researchers have come to the same conclusion: Children's cultural environments can have a huge influence on what children learn and how they develop. Finally, the two theorists offer differing perspectives on how language enters into the picture. For Piaget, language certainly enhances cognitive development: It provides many labels (symbols) that help children mentally represent their world, and it's the primary means through which children gain knowledge of other people's diverse perspectives on various situations and topics. For Vygotsky, however, language is absolutely essential for cognitive growth. Children's thought processes are internalized versions of social interactions that are largely verbal in nature. Furthermore, in their conversations with adults, children learn the meanings their culture ascribes to particular events and gradually begin to interpret the world in culture-specific ways. In addition, through two language-based phenomena—self-talk and inner speech—children begin to guide their own behaviors in ways that others have previously guided them. With such benefits in mind, many contemporary theorists share Piaget's and Vygotsky's belief that acquiring language is an important—perhaps the most important—factor in cognitive development (e.g., Newcombe, 2017; Pinker, 2007; Premack, 2004; Spelke, 2003). We can better understand cognitive development, then, when we also know something about language development

theoretical issues regarding language development

Children's immediate environments play a significant role in their language development. The richer the language that children hear—that is, the greater the variety of words and the greater the complexity of syntactic structures to which other people expose them—the faster their vocabulary develops (Hoff, 2003; Jones & Rowland, 2017; Raikes et al., 2006; Risley & Hart, 2006). Yet children don't simply absorb the language spoken around them; instead, they appear to use what they hear to construct their own understandings of the language, including knowledge about word meanings, rules governing how words can be combined into sentences, and so on (Cairns, 1996; Cromer, 1987; Karmiloff-Smith, 1993). Thus, we see in language development some of the knowledge construction of which Piaget spoke. Most developmental theorists agree that heredity is also involved in language development to some degree. Human beings have the capacity to acquire a far more complex language than any other species on the planet. Exactly what human beings inherit that enables them to learn language is a matter of considerable controversy, however. At a minimum, infants inherit a few key predispositions—for instance, a preference for human voices over other sounds and an ability to hear very subtle differences among speech sounds—that make language learning possible (DeCasper & Fifer, 1980; Jusczyk, 1995; P. K. Kuhl, 2004; J. L. Locke, 1993). In addition, some theorists believe that part of our genetic heritage is a language acquisition device, a language-specific learning mechanism (also referred to as universal grammar), that enables infants and toddlers to acquire many intricacies of language in an amazingly short amount of time (Chomsky, 1972, 2006; M. Gopnik, 1997; Karmiloff-Smith, 1993; Yang, Crain, Berwick, Chomsky, & Bolhuis, 2017). Other theorists believe instead that children learn language in much the same way they learn other things about their environment and culture: through detecting and making use of regular patterns of input from their social environment (Gentner & Namy, 2006; Pelucchi, Hay, & Saffran, 2009; Saffran, 2003). Some research evidence does point to a language-specific developmental mechanism for at least some aspects of language learning (Lai, Fisher, Hurst, Vargha-Khadem, & Monaco, 2001; Maratsos, 1998; Trout, 2003). Children of all cultures learn language very quickly and acquire complex syntactic structures even when those structures aren't necessary for effective communication. In addition, brain research reveals that certain parts of the left hemisphere seem to be biologically predisposed to specialize in either understanding or producing speech (Aitchison, 1996; J. L. Locke, 1993). Additional evidence for heredity's influence comes from research findings suggesting that there may be sensitive periods in some aspects of language development. Children who have little or no exposure to any language in the early years often have trouble acquiring complex language later on, even with intensive language instruction (Curtiss, 1977; Newport, 1990). Furthermore, when learning a second language, people have an easier time mastering correct pronunciations, various verb tenses, and complex grammatical structures if they're immersed in the language during childhood or early adolescence (Bialystok, 1994; Bortfeld & Whitehurst, 2001; Bruer, 1999; Norman & Bylund, 2016; M. S. C. Thomas & Johnson, 2008). Possibly such sensitive periods reflect biologically built-in time frames for learning language. Alternatively, perhaps what appear to be predetermined "best" times for learning particular aspects of language are simply the result of the brain's tendency to adapt fairly quickly to whatever forms its early auditory environment takes (P. K. Kuhl, 2004; P. K. Kuhl, Conboy, Padden, Nelson, & Pruitt, 2005)

contemporary extensions and applications of piaget's theory

Despite its shortcomings, Piaget's theory has had considerable influence on present-day thinking about cognitive development and classroom practice. A few contemporary neo-Piagetian theories integrate elements of Piaget's theory with current theories of thinking and learning. Furthermore, educators have found many of Piaget's ideas quite useful in instructional settings. We'll examine three of his ideas—his clinical method, his emphasis on the importance of hands-on experiences, and his concept of disequilibrium—in upcoming sections. The Into the Classroom feature "Applying Piaget's Theory" offers additional suggestions for translating Piaget's ideas into classroom practice Neo-Piagetian Theories Neo-Piagetian theories echo Piaget's belief that cognitive development depends somewhat on brain maturation. For instance, some neo-Piagetian theorists suggest that a component of the human memory system known as working memory is especially important for cognitive development. In particular, working memory is a brain-based mechanism that enables people to temporarily hold and think about a small amount of new information. Children's working memory capacity increases with age, and thus their ability to think about several things at the same time also increases (Case & Mueller, 2001; Fischer & Bidell, 2006; Lautrey, 1993). Neo-Piagetian theorists reject Piaget's notion that a single series of stages characterizes children's overall cognitive development. However, they speculate that cognitive development in specific content domains—for example, in understanding numbers or spatial relationships—often has a stagelike nature (e.g., Case, 1985; Case & Okamoto, 1996; Fischer & Immordino-Yang, 2002). Children's entry into a particular stage is marked by the acquisition of new abilities that children practice and gradually master over time. Eventually, they integrate these abilities into more complex structures that mark their transition into a subsequent stage. Thus, as is true in Piaget's theory, the stages are hierarchical, with each one being constructed out of abilities acquired in the preceding stage. Even in a particular subject area, however, cognitive development isn't necessarily a single series of stages through which children progress as if they were climbing rungs on a ladder. In some cases, development might be better characterized as progression along "multiple strands" of skills that occasionally interconnect, consolidate, or separate in a weblike fashion (Fischer & Daley, 2007; Fischer & Immordino-Yang, 2002). From this perspective, children may acquire more advanced levels of competence in a particular area through any one of several pathways. For instance, as they become increasingly proficient in reading, children may gradually develop various word decoding and reading comprehension skills, and they draw on all of these skills when reading a book. However, the rate at which each skill is mastered varies from one child to the next Piaget's Clinical Method as an Assessment Tool Earlier we considered Piaget's clinical method, in which an adult probes children's thoughts about a particular task or problem through a sequence of individually tailored questions (recall the dialogue with Brian about the wooden beads). By presenting a variety of Piagetian tasks involving either concrete or formal operational thinking skills (e.g., conservation or separation and control of variables) and asking students to explain what they're thinking, we can gain valuable insights into their logical reasoning abilities (e.g., diSessa, 2007). We need not stick to traditional Piagetian reasoning tasks, however. To illustrate, a teacher might present various kinds of maps (e.g., a road map of Spain, an aerial map of Los Angeles, a three-dimensional relief map of a mountainous area) and ask students to interpret what they see. Children in the early elementary grades are apt to interpret maps very concretely, perhaps thinking that lines separating states and countries are actually painted on the Earth. They might also have difficulty with the scale of a map, perhaps thinking that a line can't be a road because "it's not fat enough for two cars to go on" or that a mountain depicted by a bump on a relief map isn't really a mountain because "it's not high enough" (Liben & Myers, 2007, p. 202). Understanding the concept of scale in a map requires proportional reasoning—an ability that doesn't fully emerge until after puberty—and thus it's hardly surprising that young children will be confused by it. Hands-on Experiences Piaget suggested that exploration of the physical environment should be largely a child-initiated and child-directed effort. Young children can certainly learn a great deal from their informal interactions with sand, water, and other natural substances (Hutt, Tyler, Hutt, & Christopherson, 1989). And in the elementary and secondary school grades, opportunities to manipulate physical objects—or their virtual equivalents on a computer screen—can enhance students' understanding of basic mathematical and scientific concepts (M. C. Brown, McNeil, & Glenberg, 2009; Lorch et al., 2010; Sarama & Clements, 2009; Sherman & Bisanz, 2009). Researchers are finding, however, that hands-on experiences are typically more effective when combined with instruction that helps students draw appropriate conclusions from what they observe (Fujimura, 2001; Hardy, Jonen, Möller, & Stern, 2006; R. E. Mayer, 2004). In the absence of teacher guidance and directive questions, students may draw inferences based solely on what they see and feel—for instance, erroneously concluding that a very small piece of Styrofoam must have no weight whatsoever—and they may fail to separate and control variables in their experimentation (M. C. Brown et al., 2009; Lorch et al., 2014; C. L. Smith, 2007). In addition, it can be tempting to utilize readily available technological resources (e.g., websites or videos) to provide students with virtual hands-on experiences; these can be powerful educational tools, but teachers need to keep in mind that students may not have acquired necessary cognitive skills to take full advantage of the technology. For example, a teacher may discover a website that relates to their current science topic; nevertheless, some students may still require hands-on experiences with concrete examples, rather than abstract representations from a website. Creating Disequilibrium: The Value of Sociocognitive Conflict As noted earlier, interaction with peers helps children realize that others often view the world differently than they do and that their own ideas aren't always completely logical or accurate. Furthermore, interactions with age-mates that involve wrestling with contradictory viewpoints—interactions that involve sociocognitive conflict—create disequilibrium that may spur children to reevaluate and possibly revise their current understandings. Whereas children may accept an adult's ideas without argument, some may be quite willing to disagree with and challenge the ideas of their peers (D. W. Johnson & Johnson, 2009b; Lampert, Rittenhouse, & Crumbaugh, 1996; M. C. Linn, 2008). Ultimately, social interaction—not only with peers but also with adults—is probably even more important for children's cognitive development than Piaget realized. Lev Vygotsky's theory, which we turn to now, describes additional ways in which interactions with fellow human beings promote cognitive growth.

Piaget theory of cognitive development

Do you think of yourself as a logical person? Just how logical are you? Try out your logical reasoning abilities in the following exercise. You undoubtedly found the first problem quite easy; there are, of course, more wooden beads than brown beads. And when you read the second problem, you probably concluded fairly quickly that, yes, all children must be mammals. The third problem is a bit tricky: It follows the same line of reasoning as the second, but the logical conclusion—all children must be candy—contradicts what is true in reality. In the early 1920s, Swiss biologist Jean Piaget began studying children's responses to problems of this nature. He used an approach he called the clinical method, in which an adult presents a task or a problem and asks a child a series of questions about it, modifying later questions to the child's responses to previous ones. For example, let's look at what happened when a researcher in Piaget's laboratory presented the wooden beads problem to a 6-year-old, whom we'll call Brian1 : Adult: Are there more wooden beads or more brown beads? Brian: More brown ones, because there are two white ones. Adult: Are the white ones made of wood? Brian: Yes. Adult: And the brown ones? Brian: Yes. Adult: Then are there more brown ones or more wooden ones? Brian: More brown ones. (Dialogue from Piaget, 1952a, pp. 163-164) During further questioning, Brian continued to assert that the brown beads outnumbered the wooden beads. In an effort to help him see otherwise, the adult asked him to draw two necklaces, one made of the brown beads and another made of the wooden beads. Brian drew a series of black rings for the brown-beads necklace; he drew a series of black rings plus two white rings for the wooden-beads necklace. Adult: Good. Now which will be longer, the one with the brown beads or the one with the wooden beads? Brian: The one with the brown beads. (Dialogue from Piaget, 1952a, p. 164) Piaget suggested that young children such as Brian have trouble with class inclusion tasks in which they must think of an object as simultaneously belonging to a category and to one of its subcategories—in this case, thinking of a bead as being both brown and wooden at the same time. Piaget found that many 4- and 5-year-olds have difficulty with class inclusion tasks such as the beads problem, but that 7- and 8-year-olds almost always respond to such tasks correctly. He also found that 10-year-olds have an easier time with logic problems that involve real-world phenomena (such as categories and subcategories of living creatures) than with problems involving hypothetical and contrary-to-fact ideas (such as candy children), whereas many adolescents can effectively deal with both kinds of problems. These observations, which we will discuss in greater detail, have obvious implications for the education of children. Through a wide variety of thought-provoking questions and tasks, Piaget and his colleagues discovered a great deal about what and how children think about the world around them (e.g., Inhelder & Piaget, 1958; Piaget, 1929, 1952b, 1959, 1970, 1980). Piaget integrated his findings into a theory of cognitive development that has made major contributions to contemporary understandings of children's learning and development

vygotskys theory theory of cognitive development

In Piaget's view, children are largely in control of their own cognitive development; for example, they initiate interactions with objects in their environment and develop self-constructed understandings of what they observe. In contrast, an early Russian developmentalist, Lev Vygotsky, believed that the adults in any society intentionally foster children's cognitive development in a somewhat systematic manner. Because Vygotsky emphasized the importance of adult instruction and guidance for promoting cognitive development— and more generally because he emphasized the influence of social and cultural factors on children's cognitive growth—his perspective is known as a sociocultural theory. Vygotsky and his students conducted many studies of children's thinking from the 1920s until Vygotsky's early death from tuberculosis in 1934. Instead of determining the kinds of tasks children could successfully perform on their own (as Piaget did), Vygotsky often examined the kinds of tasks children could complete only with adult assistance. For example, he described two hypothetical children who could, without help, do things that a typical 8-year-old might be able to do. He would give each of the children progressively more difficult tasks and offer a little bit of assistance, perhaps by asking a leading question or suggesting a reasonable first step. With such help, both children could almost invariably tackle more difficult tasks than they could handle on their own. However, the range of tasks that the two children could complete with assistance might be quite different, with one child stretching his or her abilities to succeed at typical 12-year-old-level tasks and the other succeeding only with typical 9-year-old-level tasks (Vygotsky, 1934/1986, p. 187). Western educators were largely unfamiliar with Vygotsky's work until the last few decades of the 20th century, when his major writings were translated from Russian into English (e.g., Vygotsky, 1934/1986, 1978, 1997). Although Vygotsky never had the chance to develop his theory fully, his views are clearly evident in many contemporary theorists' discussions of learning and development and have become increasingly influential in guiding teachers' classroom practices (Jovanović, 2015). As you will see, Vygotsky's theory provides a rationale for teachers being actively involved in supporting students' learning and development, thus fostering the enhancement of cognitive abilities

Piaget basic assumptions

Piaget introduced a number of ideas and concepts to describe and explain the changes in logical thinking he observed in children and adolescents. • Children are active and motivated learners. Piaget noticed that children want to learn! They are naturally curious, and they actively seek out new information so that they can make sense of their worlds. They love to play and experiment with new objects and try out new ideas. • Children construct rather than absorb knowledge. As a prospective teacher, you may think about learning as a one-way process: the teacher "teaches" the students. However, as Piaget observed, children don't just passively soak up a collection of isolated facts. Instead, they pull their experiences together into an integrated view of how the world operates. Although teachers may provide students with wonderful experiences and information, students construct their own knowledge by synthesizing these various experiences. For example, by observing that objects always fall down (never up) when dropped, children begin to construct a basic understanding of gravity. As they interact with family pets, visit farms and zoos, and look at picture books, they develop more complex understandings of animals. Because Piaget proposed that children construct their own beliefs and understandings from their experiences, his theory is sometimes called a constructivist theory or, more generally, constructivism. In Piaget's terminology, the things children do and know are organized as schemes—groups of similar actions or thoughts that are used repeatedly in response to the environment. Initially, children's schemes are largely behavioral in nature, but over time they become increasingly mental and, eventually, abstract. For example, an infant may have a putting-things-in-mouth behavioral scheme that she applies to a variety of objects, including her thumb, cookies, and toys. A 7-yearold may have a mental scheme for identifying snakes that includes their long, thin bodies; lack of legs; and slithery nature. A 13-year-old may have an abstract scheme for what constitutes fashion, allowing him to classify certain peers as being either really cool or "total losers." Over time, children's schemes are modified with experience, and many become integrated with one another. For instance, children begin to take hierarchical interrelationships into account: They learn that poodles, golden retrievers, and German shepherds are all dogs; that dogs, snakes, and birds are all animals; and that both animals and plants are living organisms. A progressively more organized body of knowledge and thought processes allows children to think in increasingly intricate and logical ways, and to learn increasingly complex information as they progress through school. • Children continually learn new things through two complementary processes: assimilation and accommodation. Assimilation involves responding to or thinking about an object or event in a way that's consistent with one's current way of thinking (i.e., with one's existing scheme). For example, an infant may assimilate a new teddy bear into her putting-things-in-mouth scheme. A 7-year-old may quickly identify a new slithery creature in the garden as a snake. A 13-year-old may readily label a classmate's clothing or hairstyle as being either quite fashionable or "soooo yesterday." But sometimes children can't easily interpret and respond to a new object or event using their existing schemes. In these situations, children need to adjust their current ways of thinking to make better sense of this newly learned information. This process is referred to as accommodation. Accommodation can occur in two ways: Children either (1) modify an existing scheme to account for the new object or event or (2) form a new scheme in order to make sense of the new object or event. For example, an infant may have to open her mouth wider than usual to accommodate a teddy bear's fat paw. A 13-year-old may have to revise his existingscheme of fashion according to changes in what's hot and what's not. A 7-year-old who encounters a long, slithery creature with four legs may realize that she can't apply the snake scheme (snakes don't have legs) and thus, after some consideration, may acquire a new scheme—salamander. Assimilation and accommodation typically work hand in hand as children develop their knowledge and understanding of the world. Children interpret each new event within the context of their existing knowledge (assimilation), but at the same time may modify their knowledge as a result of the new event (accommodation). Accommodation rarely happens without assimilation: children can benefit from, or accommodate to, new experiences only when they can relate those experiences to their current knowledge and beliefs. As assimilation and accommodation occur, these adjustments in children's thinking result in cognitive development (Miller, 2011). Interactions with one's physical and social environments are essential for cognitive development. According to Piaget, active experimentation with the physical world is critical for cognitive development. By exploring and manipulating physical objects—for instance, fiddling with sand and water, playing games with balls and bats, and conducting science experiments—children come to understand more complex and abstract concepts (e.g., Sim & Xu, 2017). For example, playing with sand and water ultimately can help children to see the effects of erosion, which is a rather complex concept; playing with balls and bats helps children discover principles related to force and gravity. In Piaget's view, interaction with other people is equally important. Frequent social interactions—both pleasant (e.g., normal conversations with friends) and unpleasant (e.g., conflicts about sharing and fair play)—help young children come to realize that different people see things differently, and that their own view of the world isn't necessarily completely accurate, logical, or shared by others. As children get older, discussions and disagreements about complex issues and problems can help them recognize and reexamine inconsistencies in their own reasoning. • A process of equilibration promotes progression toward increasingly complex thought. Piaget suggested that children are often in a state of equilibrium: They can comfortably interpret and respond to new events using existing schemes. But as children grow older and expand their horizons, they sometimes encounter situations for which their current knowledge and skills are inadequate. Such situations create disequilibrium, a sort of mental discomfort that stimulates them to try to make sense of what they're observing. By replacing, reorganizing, or better integrating certain schemes (i.e., through accommodation), children can better understand and address previously puzzling events. The process of moving from equilibrium to disequilibrium and back to equilibrium again is known as equilibration. In Piaget's view, equilibration, along with children's intrinsic desire to achieve equilibrium, promote the development of more complex levels of thought and knowledge. As an example, let's return to Brian's responses to the beads problem. Recall that the adult asked Brian to draw two necklaces, one made with the brown beads and one made with the wooden beads. The adult presumably hoped that after Brian drew a brown-and-white necklace that was longer than an all-brown necklace, he would notice that his drawings were inconsistent with his statement that there were more brown beads. The inconsistency might have led Brian to experience disequilibrium, perhaps to the point where he would revise his conclusion. In this case, however, Brian was apparently oblivious to the inconsistency, remained in equilibrium, and thus had no need to revise his thinking. • In part as a result of maturational changes in the brain, children think in qualitatively different ways at different ages. Long before researchers knew much about how the brain changes with age, Piaget speculated that it does change in significant ways, and that such changes enable more complex thought processes. He suggested that major neurological changes take place throughout childhood. These changes allow new abilities to emerge, such that children progress through a sequence of stages that reflect increasingly sophisticated thought. As you've already learned, the brain does, in fact, continue to develop throughout childhood and adolescence, but whether some of its changes enable the cognitive advancements Piaget described is still an open question.

Diversity in language development

Some diversity in language development seems to be the result of biology. For instance, children with a specific language impairment develop normally in all respects except for language. These children have trouble perceiving and mentally processing particular aspects of spoken language—perhaps the quality, pitch, duration, or intensity of specific speech sounds. Often, although not always, the source of the impairment can be traced to heredity or a specific brain abnormality (Bishop, 2006; Bishop, McDonald, Bird, & Hayiou-Thomas, 2009; Corriveau, Pasquini, & Goswami, 2007; Spinath, Price, Dale, & Plomin, 2004). Cultural factors play a role in linguistic diversity as well. For example, different cultural groups may nurture different dialects—distinct forms of a language that characterize particular ethnic groups or geographic regions—and different social conventions for human conversation (i.e., different pragmatic skills; Adger et al., 2007; Kitayama & Cohen, 2007; Tyler, Uqdah, et al., 2008). Culture also is related to exposure to language— in some cultures, linguistic interactions with young children may be less common than in others (e.g., Weber, Fernald, & Diop, 2017). Occasionally, a cultural or ethnic group specifically nurtures certain aspects of language development. For example, many inner-city African American communities make heavy use of figurative language—such as similes, metaphors, and hyperbole (intentional exaggeration)—in their day-to-day conversations, jokes, and stories (C. D. Lee, 2005; H. L. Smith, 1998; Smitherman, 2007). The following anecdote illustrates this point: I once asked my mother, upon her arrival from church, "Mom, was it a good sermon?" To which she replied, "Son, by the time the minister finished preaching, the men were crying and the women had passed out on the floor." (H. L. Smith, 1998, p. 202) With such a rich oral tradition, it isn't surprising that many inner-city African American youth are especially advanced in their use and understanding of figurative language (Ortony, Turner, & Larson-Shapiro, 1985; H. L. Smith, 1998; Smitherman, 2007)

CRITIQUING PIAGETS THEORY

Some of Piaget's key ideas have stood the test of time, including his ideas that children construct their own knowledge about the world, that they must relate new experiences to what they already know, and that encountering puzzling phenomena can sometimes spur them to revise their understandings. Piaget's descriptions of processes that propel development—especially assimilation, accommodation, and equilibration—can be frustratingly vague, however (M. Chapman, 1988; diSessa, 2006; Klahr, 2001). And interaction with one's physical environment, although certainly valuable, may be less critical than Piaget believed. For instance, children with significant physical disabilities, who can't actively experiment with physical objects, learn a great deal about the world simply by observing what happens around them (Bebko, Burke, Craven, & Sarlo, 1992; Brainerd, 2003). A Second Look at Piaget's Stages Piaget's proposal that cognitive development progresses in stages has sparked a great deal of follow-up research. In general, this research supports Piaget's proposed sequence in which different abilities emerge, but not necessarily the ages at which they emerge. Piaget probably underestimated the thinking capabilities of preschoolers and elementary school students. For example, under some circumstances, preschoolers are capable of class inclusion and conservation, and they have some ability to comprehend abstract and contrary-to-fact ideas (S. R. Beck, Robinson, Carroll, & Apperly, 2006; Goswami & Pauen, 2005; McNeil & Uttal, 2009; Rosser, 1994). Many first and second graders can understand and use simple proportions (e.g., ½, 1⁄3, ¼) if they can relate the proportions to everyday objects and situations (Empson, 1999; Van Dooren, De Bock, Hessels, Janssens, & Verschaffel, 2005). And some older elementary school children can separate and control variables if a task is simplified in some way (Lorch et al., 2010; Metz, 1995; Ruffman, Perner, Olson, & Doherty, 1993). Yet Piaget seems to have overestimated what adolescents can do. Formal operational thinking processes emerge more gradually than he suggested, and even high school students and adults don't necessarily use them regularly (Flieller, 1999; Kuhn & Franklin, 2006; Morra et al., 2008; Tourniaire & Pulos, 1985). Many adolescents seem to better understand abstract ideas when those ideas are accompanied by concrete examples and materials (Blair & Schwartz, 2012; Kaminski & Sloutsky, 2012). Furthermore, students may demonstrate formal operational thought in one content domain while thinking concretely in another (Lovell, 1979; Tamburrini, 1982). Figure 2.5 is an example of a language arts activity that probably could be accurately completed by students who have acquired concrete operations; however, it also requires some logical deduction that might benefit from the use of some formal operational processes. Thus a sixth grade teacher using this activity might have some students who can complete it more readily than others. Explicit training and other structured experiences can sometimes help children acquire reasoning abilities sooner than Piaget thought was possible (Brainerd, 2003;Kuhn, 2006; Lutz & Sternberg, 1999; Protzco, Aronson, & Blair, 2013). For example, children as young as age 4 or 5 begin to show conservation after having experience with conservation tasks, especially if they can actively manipulate the task materials and discuss their reasoning with someone who already exhibits conservation (Halford & Andrews, 2006; Siegler & Chen, 2008; Siegler & Lin, 2010). Similarly, instruction with concrete or graphic materials can help children and adolescents better understand how to work with fractions and other proportions (Fujimura, 2001; Jitendra, Star, Rodrigues, Lindell, & Someki, 2011; Sarama & Clements, 2009). And in the upper elementary grades, children become increasingly able to separate and control variables when they have many experiences that require them to do so, and they can more easily solve logical problems involving hypothetical ideas if they're taught relevant problem-solving strategies (Kuhn & Pease, 2008; S. Lee, 1985; Lorch et al., 2014; Schauble, 1990). Thus, whereas Piaget proposed a fairly structured, universal ordering to cognitive development, more recent research suggests that there is more variation in children's thinking skills develop over time, and that this variation is attributable in some ways to context. For example, recent research indicates that cognitive development is affected in particular by diet of pregnant mothers and newborn babies (i.e., cognitive abilities in children seem to be positively affected by specific dietary supplements), exposure of children to early educational interventions, interactively reading with children, and attendance at a preschool (Protzco et al., 2013). In light of such evidence, most researchers believe that the logical thinking abilities Piaget described emerge in gradual, trend-like ways rather than in discrete stages. Nevertheless, as you'll see shortly, some theorists have offered stage-based theories that might account for children's logical reasoning in specific skill areas or content domains.

CASE STUDY

The situation in Mrs. Bennington's classroom is actually quite typical of a first-grade classroom. Some children will understand seemingly obvious things, whereas others may not. There are several strategies that Mrs. Bennington can use with Ben. She might decide that this is too confusing for Ben right now, and not try to push this topic. However, she also might decide to break her students into small groups and help them explore plants that produce food. As you consider this scenario, you can probably see that Keisha is able to understand that a carrot can be considered both a plant and a food; she can see that the same object can be classified in two different ways. However, Ben does not seem to be able to understand yet that a carrot can be both a plant and a food. Mrs. Bennington is faced with the very typical situation of having students in the same classroom who are at different levels of cognitive development. Classroom instruction must take into account the physical, cognitive, personal, and social characteristics and abilities that students at a particular age are likely to have, as well as differences between students. In this chapter, we'll look at general principles of development and then zero in on children's cognitive development—that is, developmental changes in thinking, reasoning, and language. As we look at these topics in the pages ahead, we'll be better able to understand Mrs. Bennington's dilemma

Vygotsky's basic assumptions

Vygotsky acknowledged that biological factors—such as maturational processes in the brain—play a role in cognitive development (Ghassemzadeh, Posner, & Rothbart, 2013). Children bring certain characteristics and dispositions to the situations they encounter, and their responses vary accordingly. Furthermore, children's behaviors, which are influenced in part by inherited traits, affect the particular experiences children have (Vygotsky, 1997). However, Vygotsky's primary focus was on the role of children's social and cultural environments in fostering cognitive growth—and especially in fostering those complex mental abilities that are unique to human beings as a species. Following are central ideas and concepts in Vygotsky's theory: