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Zpd: Implications For Teaching Essay, Research Paper
THE ZONE OF PROXIMAL DEVELOPMENT AND ITS IMPLICATIONS FOR LEARNING AND TEACHING
There can be little doubt that, in the English-speaking world at least, it is the “zone of proximal development” that has been Vygotsky’s most important legacy to education. Indeed, it is the only aspect of Vygotsky’s genetic theory of human development that most teachers have ever heard of and, as a result, it is not infrequently cited to justify forms of teaching that seem quite incompatible with the theory as a whole. This centenary conference therefore seems an appropriate occasion to review Vygotsky’s exposition of the zpd and to consider the ways in which this seminal concept has been modified and extended in subsequent work.
Although the zpd is often said to be a central concept within his theory, its explicit formulation appeared quite late in Vygotsky’s writings and then in two rather different contexts. One version, translated into English as “Interaction between Learning and Development” (chapter 6 of Mind in Society, 1978), occurred in a posthumously published collection of essays entitled Mental Development of Children and the Processes of Learning (Vygotsky, 1935). Here, the immediate context in which the concept of the zpd is presented is that of the assessment of children’s intellectual abilities and, more specifically, as a more dynamic conception of intellectual potential than that represented by an IQ score. Vygotsky defines the zone of proximal development as “the distance between the actual developmental level as determined by independent problem solving and the level of potential development as determined through problem solving under adult guidance or in collaboration with more capable peers” (1978, p.86). In other words, operationally, it is the zone defined by the difference between a child’s test performances under two conditions: with or without assistance.
The second version occurs in Vygotsky’s last major work, Thinking and Speech (1934/1987), and is embedded in chapter 6, in which he discusses “The Development of Scientific Concepts in Childhood”. Here, the emphasis falls more heavily on instruction and, in particular, on its role in relation to the development of those higher mental functions that are characterized by conscious awareness and volition. In this context, the significance of the zpd is that it determines the lower and upper bounds of the zone within which instruction should be pitched. “Instruction is only useful when it moves ahead of development” (p.212), “leading the child to carry out activities that force him to rise above himself” (p.213). How instruction is conceived to operate in practice is briefly sketched in a description of the hypothesized processes leading to the child’s solving of a test problem involving a causal relationship in the social sciences. Vygotsky writes: “The teacher, working with the school child on a given question, explains, informs, inquires, corrects, and forces the child himself to explain. All this work on concepts, the entire process of their formation, is worked out by the child in collaboration with the adult in instruction. Now, [i.e. in the test situation] when the child solves a problem … [he] must make independent use of the results of that earlier collaboration” (pp.215-216).
Written at about the same time, these two expositions have several common features, including the emphasis on learning leading development, and on the role of adult assistance and guidance in enabling the child to do in collaboration with more expert others what he or she is not yet able to do alone. These are memorably summed up in the contrast Vygotsky makes between development in animals and humans: “animals are incapable of learning in the human sense of the term; human learning presupposes a specific social nature and a process by which children grow into the intellectual life of those around them” (1978, p.88). In this sentence, one can see how the zpd was probably destined to play a pivotal role in the larger theory that Vygotsky was constructing. Unfortunately, however, he did not live to work out the implications of what is here only sketched. Instead, what we have in the work that was completed is, on the one hand, some provocative and generative metaphors and, on the other, two rather specific applications of the concept of the zpd that may appear to be rather out of keeping with contemporary Vygotskian-inspired educational practice.
On the basis of these two texts alone, therefore, there remain a number of questions about how the concept should be understood. For example, did Vygotsky consider that, at any particular point in a child’s development, the zpd was a fixed and quantifiable attribute of that particular child? And did it apply only to intellectual development? Was the assistance that could be given by others restricted to deliberate instruction of the kind described above? And did it necessarily have to be given in face-to-face verbal interaction? And, perhaps most important, should the account he offered of learning-and-teaching in the zpd be taken as universal and normative or as merely descriptive of the practices of a particular stratum of the society in which he lived?
It is a central tenet of cultural historical theory, however, that tools – including cognitive artifacts – are created at a particular moment in the historical trajectory of a culture, in response to the demands of the activity in which they are used, and that they continue to be modified, in use, by those who continue the activity. The concept of the zone of proximal development is just such a cognitive artifact/tool. As Wertsch (1985) suggests, it was formulated by Vygotsky to tackle two specific problems, as these were construed at a particular moment in his ongoing construction of a more general theory of development; moreover, as well as being incomplete, his exposition of the concept bears the stamp of the more general intellectual and practical concerns of his generation in post-revolutionary Russia. However, since its first formulation, the zpd has continued to serve a valuable role as a tool for thinking about human development by theorists and researchers in other cultural and historical contexts. Not surprisingly, therefore, it has itself undergone considerable modification in the process. In the remainder of this paper, I shall offer a brief overview of what I see to be the main trends in this development.
Some of the earliest attempts to apply Vygotsky’s concept occurred in the context of testing. Picking up his concern with appropriate assessment, attempts were made to use the concept of the zpd in the administration of tests under two conditions: without and with assistance. Typically, the aim of such assessment was, and continues to be, the categorization of individual students with a view to their appropriate placement in educational programs, often of a remedial kind (Campione and Brown, 1987; Feuerstein, 1979). In these applications, the tests used have typically been ’standardized’ in form and administered on a single occasion in a setting removed from ongoing classroom or home activities. However, it could be argued that, although compatible with Vygotsky’s (1978) discussion of the value of the concept of the zpd for diagnostic assessment, the practice of administering such decontextualized tests is at variance with the requirement that assessment be related to the cultural activities in which the tested subject habitually engages. Certainly, this seems to be the implication of Cole’s (1985) criticism of cross-cultural research that fails to embed testing in activity contexts familiar to those who are tested.
Since the purpose of assessment of the zpd is to enable the provision of appropriate instruction, such assessment, it might be argued, is more appropriately carried out in the context of particular students’ engagement in an educational activity (Allal and Ducrey, 1996). Here, the aim is the diagnosis of the student’s ability to cope with the specific task and of the nature of the difficulties that he or she is experiencing so that, when the teacher intervenes, the intervention is tailored to the student’s actual needs rather than to the assumed needs of students in general at that age or grade level. This mode of diagnostic assessment has been employed at two levels, corresponding to the distinction that is frequently made between summative and formative assessment. At the summative level, a student’s performance on an end-of-unit test or assignment can be made the basis on which the teacher then works with the student individually or in a small, relatively homogeneous group. The practices of “reciprocal teaching”, developed by Palincsar and Brown (1984) would seem to fit into this category. The assistance given under these conditions can be seen as ‘remedial’, designed to enable the student to master some specific skill or those parts of the unit with which he or she had not been successful under normal instruction. While such practices are certainly compatible with Vygotsky’s theory, they might in many cases equally be characterized as a regular feature of good traditional pedagogy.
A more dynamic conception of diagnostic assessment can be found in a number of pedagogical approaches that explicitly make appeal to the concept of the zpd. Here, the assessment is both formative and informal, and occurs as the teacher, either as a co-participant or as a bystander, observes how students are tackling particular tasks and, on this basis, attempts to intervene in a manner that is both responsive to the students’ needs and intended to assist them to achieve mastery of the task (Schneuwly and Bain, 1993). Although geared to the responses of a group, rather than of an individual student, this dynamic use of assessment to guide teaching is also the basis of what Tharp and Gallimore (1988) refer to as “instructional conversation”. It is this latter, situated, use of assessment that Allal and Ducrey (1996) consider best fulfills Vygotsky’s concern to use assessment to guide instruction.
All the above assessment practices are undertaken with a view to providing appropriate instruction. However, the judgments that they lead to are of quite different orders of specificity with respect to the nature of the instruction that is deemed appropriate. In introducing the notion of the zpd in relation to the assessment of children with “delayed development”, Vygotsky (1978) was essentially arguing for appropriate placement based on the child’s learning potential. His chief concern was that the placement should ensure that the child had the opportunity for “good learning”, i.e. learning that is in advance of his or her development. What form of instruction might best provide such opportunities was not addressed on that occasion.
In the chapter in Thinking and Speech in which Vygotsky focuses more directly on instruction, the emphasis is on enabling the mastery of scientific concepts, which are seen as psychological tools that mediate higher mental functioning. The zpd is used in this context to identify the window for instruction: “instruction is maximally productive when it occurs at a certain point in the zone of proximal development” (1987, p.212). However, although he emphasizes the “decisive influence” that instruction has on the course of development (p.213), Vygotsky does not treat the nature of instruction itself as problematic, seemingly accepting the current practices with which he was familiar as adequate, provided they were appropriately in advance of development.
The one place in which Vygotsky gives a clearer indication of the form that “good instruction” might take is in his discussion of the Montessori approach to the early stages of literacy learning. The passage is worth quoting at some length.
… teaching should be organized in such a way that reading and writing are necessary for something. If they are used only to write official greetings to the staff or whatever the teacher thinks up (and clearly suggests to them), then the exercise will be purely mechanical and may soon bore the child; his activity will not be manifest in his writing and his budding personality will not grow. Reading and writing must be something the child needs … writing must be “relevant to life” – in the same way that we require a “relevant” arithmetic. .A second conclusion, then, is that writing should be meaningful for children, that an intrinsic need should be aroused in them, and that writing should be incorporated into a task that is necesssary and relevant for life. (1978, pp.117-8)
Vygotsky is here writing about children of preschool age and, as he says elsewhere, “instruction takes on forms that are specific to each age level” (1987, p.213). We cannot be certain, therefore, whether he considered that the meaningfulness of educational activities to the learner and their relevance to life were essential characteristics of instruction at all ages and stages of development. However, recent commentators have for the most part assumed that this is what is implied by his theory as a whole.
As a result of Vygotsky’s lack of specificity about the nature of instruction – at least in the context of his discussion of the zpd – there is considerable diversity in the instructional approaches that have been developed on the basis of his ideas. One crucial difference is in the role that students are given in shaping the goals of learning activities. On the one hand, there are approaches in which the zpd is appealed to only in determining the level at which instruction is pitched. Here, it is assumed that it is possible to establish the zpd of the class as a whole and to modify instructional input and task demands accordingly (Hedegaard, 1990). A further refinement might involve the formation of groups within the class, with tasks of different levels of difficulty being assigned according to the group’s zpd. In neither case, however, would the students’ interests and goals typically play a significant role in determining the teacher’s pre-established instructional plans.
An alternative view places much greater emphasis on the importance of educational activities being meaningful and relevant to students at the time that they engage in them (Wells, 1995). Adopting this approach involves the teacher in negotiating the curriculum and in accepting that the most valuable learning opportunities are often those that emerge when students are encouraged to share the initiative in deciding which aspects of a class topic they wish to focus on and how they intend to do so. In such a context, the concept of the zpd is interpreted very differently. Not only is it assumed that the zpd applies to individuals rather than to collectives, such as a group or class, but, more importantly, it is treated as an attribute, not of the student alone, but of the student in relation to the specifics of a particular activity setting. In other words, the zone of proximal development is created in the interaction between the student and the co-participants in an activity, including the available tools and the selected practices, and depends on the nature and quality of that interaction as much as on the upper limit of the learner’s capability. A corollary of this view is that, while it may be possible to determine, in general terms, what activity settings and modes of interaction are likely to be conducive to effective learning and, on that basis, to propose the goals for class or group activities, the teacher always has to be responsive to the students’ goals, as these emerge in the course of activity, and by collaborating with them in the achievement of their individual goals, to enable them to extend their mastery and at the same time their potential for further development. From a teacher s perspective, therefore, one is always aiming at a moving target.
Learning and teaching in the zpd is clearly dependent on social interaction and, in educational settings, this most typically involves face-to-face interaction mediated by speech. The development of the higher mental functions, as envisaged by Vygotsky, is largely achieved through the construction on the intramental plane of the discourse practices that are first encountered on the intermental plane of activity-related social interaction. As Leont’ev puts it, summarizing Vygotsky’s fundamental insight:
higher psychological processes unique to humans can be acquired only through interaction with others, that is, through interpsychological processes that only later will begin to be carried out independently by the individual. When this happens, some of these proceses lose their initial, external form and are converted into intrapsychological processes.” (1981, p.56)
Indeed, the final chapter of Thinking and Speech is essentially an expansion of this last sentence as, tracing the differentiation of the child’s initial “social speech” into speech for others and “egocentric” speech for self which, in turn, becomes converted into the intrapsychological activity of “inner speech”, Vygotsky charts the development of the medium in which individual thinking is realized. As he puts it, “thought is born through words” (1987, p. 282).
There is no doubt that, in Vygotsky’s view, speech played a critical role in the child’s learning in the zpd and, hence, in the associated processes of instruction and collaborative assistance. However, as is increasingly being recognized, to focus exclusively on face-to-face interaction mediated by speech is seriously to limit our understanding of the range of modes of semiotic mediation that play a role in both interpersonal and intrapersonal thinking and problem solving; it also limits our understanding of the variety of ways in which learning in the zpd is facilitated (Smagorinsky, 1995).
In his exposition of the concept of psychological tools, Vygotsky himself made clear that the means of semiotic mediation are not limited to speech. He also included: “various systems for counting; mnemonic techniques; algebraic symbol systems; works of art; writing; schemes, diagrams, maps and mechanical drawings; all sorts of conventional signs; and so on” (1981, p.137). To these, we might also wish to add the various modes of artistic expression, such as dance, drama and musical performance. All these modes of representation are simultaneously means of communication and tools for thinking with, both when with others and when alone (John-Steiner, 1987). To recognize this is to enlarge considerably the range of applicability of the concept of learning and teaching in the zpd.
Broadening the range of modes of semiotic mediation considered also leads to the recognition that there are other sources from which learners can receive assistance in the zpd, in addition to deliberate instruction or the assistance of others who are physically present in the situation. As has been pointed out, all artifacts – both material and symbolic – are embodiments of the knowing that was involved in their production (Wartofsky, 1979) and can thus, in appropriate circumstances, make that knowing available to others, provided that the learning that is required is within the potential user’s zpd. While this is certainly the case with material artifacts, as when a new and more efficient tool becomes available for carrying out a familiar task, it is even more true of symbolic artifacts, such as written texts, charts and mathematical formulae. For those who are able to read them, such texts can provide a powerful means of self-instruction, as the reader appropriates the thoughts of others and makes them his or her own. However, as Lotman (1988) makes clear, texts are not only valuable when read “univocally”, in an attempt to reconstruct the author’s intended meaning; treating the text “dialogically” can be even more productive, as the reader uses it as “a thinking device” to develop meanings that are new not only for the reader but perhaps also for the culture as a whole. By the same token, it is probably through the dialoguing with real or imagined others that is an essential part of the process of textual composition that even the most knowledgeable others are able to continue to learn in the zpd.
Internalization: From Intermental to Intramental
The concept of “internalization” played a central role in Vygotsky’s theory of learning and development; in fact, it might be said to be the end for which interaction in the zpd was conceived as the means. As he put it: “all higher mental functions are internalized social relationships” (1981, p.164). Yet, central though the concept is, it is probably the aspect of his theory that has been the most hotly contested. For some, the concept simply lacks explanatory power; for others, it is the implied mind/body dualism that is unacceptable. But whatever the specific objection, the general thrust of this line of argument has been to question, and even to reject, the sharp distinction that Vygotsky seems to draw between internal and external, and between social (intermental) and individual (intramental) functioning.
It is not that individuals do not develop more complex (higher) modes of functioning with respect to the activities in which they engage, as they increasingly bring their actions under semioticized self-control, but that these modes of functioning are not independent of the social practices in and for which they develop. Neither in learning nor in use after mastery does it therefore seem appropiate to talk of a movement between inner and outer, such as is implied by the terms ‘internalization’ and ‘externalization’. This position is forcibly stated by Lave and Wenger in setting out their alternative theory of “legitimate peripheral participation”:
In a theory of practice, cognition and communication in, and with, the social world are situated in the historical development of ongoing activity. … First, the historicizing of the processes of learning gives the lie to ahistorical views of “internalization” as a universal process. Further, given a relational understanding of person, world, and activity, participation, at the core of our theory of learning, can be neither fully internalized as knowledge structures nor fully externalized as instrumental artifacts or overarching activity structures. Participation is always based on situated negotiation and renegotiation of meaning in the world. (1991, p.51)
More will be said below about Vygotsky’s ahistorical universalizing tendencies but, in the present context, the issue that most needs to be addressed is the sharp distinction that he appears to draw between social and individual and, perhaps even more important, the temporal sequence in which functions are said to appear on the two planes.
- СОДЕРЖАНИЕ 1. Введение 2. Составление логической модели диагностирования управляемого однофазного мостового выпрямителя 2. Структурный синтез контроллера 3. Разработка электрической принципиальной схемы контроллера 3.1 Разработка блока сбора информации ...
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