"At the beginning of development there stands the act, independent of the word, then at the end of it there stands the word which becomes the act, the word makes man’s action free. ” (Vygotsky & Luria 1994 p.170)
This chapter is an interpretation of Vygotsky's theoretical explanations of the path of cognitive development. It aims to describe the main influences upon cognitive development, and the main causes of differential development. In so doing it also aims to draw implications for the design and implementation of the current study.
Stages of development
In Vygotskian theory change can be characterised as occurring in stages. The early stages being dominated by natural processes and elementary mental functions. The later stages are dominated by social processes and higher mental functions (Wertsch 1985). The passage from one stage to another is accounted for not by quantitative differences, but by qualitative shifts (Vygotsky 1966/1991 ) \ Take for example the development of memory, this does not develop simply by being able to remember ever increasing amounts, but by becoming "logical memory", guided by meaning and deliberately applied by the child. In a series of experiments described by Leont’ev (1932/1994) the memory functions of young children were found to depend upon direct memory, that is memory functioning which is not organised with the use of memory aids (mnemonic devices). Changes with age were not caused by merely a quantitative increase in capacity. Rather the integration of mnemonic devices into memory function, that is the integration of thought with memory, appeared to create a qualitatively different form of memory, mediated memory. The use of mnemonic devices was found to dominate in the performance of adults on memory tasks (Leont'ev 1932/1994).
' F o r re fe re n c e s w ith tw o d a te s the firs t is th at o f p u b lic a tio n in the o riginal R ussian. The se c o n d is the date o f p u b lica tio n o f the E nglish translation
In the case of attention, change is said to be from behaviour which functions by being attracted by an external source, to becoming dependent upon the child's own thinking, that is 'selective attention' (Leont'ev 1932/1994). The theory suggests, as the example of memory given above also illustrates, that the end point is the development of conscious activity and deliberate mastery, where consciousness is defined as the state of awareness and understanding (Vygotsky 1934/1986).
Functional Systems
Describing development purely in terms of individual functions, such as memory, perception and attention, is inappropriate within the Vygotskian framework, as mental functions are seen to be combined in a highly complex inter-relationship. Individual functions do not develop separately because they do not operate in isolation from other mental functions. Rather, successful completion of any psychological activity depends upon their operating together. In Vygotsky's words,
"the fate of each functional ingredient of consciousness thus depends upon the deveiopment of the entire system." (Vygotsky 1934/1986 p 167).
This was illustrated in a lecture given by Vygotsky on the development of perception (Vygotsky 1960/1987). A series of experiments was described which investigated the processes involved in the perception of magnitude. Of particular interest was how compensation for changes in distance was achieved, when judging relative size. For example how are two pencils of identical length, one close and one far, perceived as being equal in size, even though on a sensory level the retinal image of the further pencil is smaller? These experiments involved judgements of relative size being made for different combinations of: objects, projected images, and the dependence upon memory of an object (eidetic memory). The results indicated that the eidetic image of the object was found to help compensate for the difference in distance when the real size of the object was being perceived. These experiments indicated that the stability and
constancy of perceptions are closely inter-linked with memory functions (Vygotsky 1960/1987).
Each level of maturity is characterised by a different relationship between mental functions. In the course of development behaviour becomes governed by increasingly more complex, and inter-related systems of functions (Vygotsky & Luria 1994). However regression to earlier less complex and more independent functioning can happen when damage or decay affects the physiological structure of the brain (Vygotsky 1966/1991).
Agents of Change
A common thread underlying change and development across all functions and domains, though not necessarily occurring simultaneously in each domain, is the mastery and use of tools and signs. Tools (also referred to as technical tools) are objects used to complete a task, such as a stick for digging. Vygotsky differentiated between human tools and animal tools. The differences between the ape and the young child lie primarily in the different combinations of psychological functions that guide the use of the tool (Vygotsky & Luria 1994). The behaviour of the ape takes place within a narrow time frame. A problem is encountered, e.g. termites are found down a narrow hole, a stick is seen and used to solve the problem by digging the termites out. Visual perception therefore dominates the process (Kohler cited in Vygotsky 1960/1987). Human activity is not so dependent upon visual perception, but is guided by a combination which includes memory functions. For example, a stick may be specifically sought from another location, or, later in development, it may be carried in anticipation of its use. Human activity is therefore more purposeful and directive.
Signs and symbols (psychological tools) are also important in distinguishing between animal and human intellect. They are central to the development of higher mental functions, through the assignation of meaning to acts and objects, and the ability they give to internalise that meaning (Vygotsky 1934/1986). The term signs, which have also been referred to as "mediational means", includes:
speech; counting systems; mnemonic techniques/devices; art; writing; maps etc. (Wertsch 1985). Since, as stated earlier, development is a process of qualitative change, the process of learning these mediational means will facilitate both the specific psychological activity to which they are being applied, and change the very nature of thought, of psychological activity in general (Vygotsky 1934/1986).
The essential difference between technical and psychological tools is that the former are external and act externally to the person to change the object of the activity being undertaken, whilst signs and symbols are psychological, in that they alter mental functioning internally. Psychological tools act more as a catalyst to activity, not altering the external object directly, but influencing the ability of
internal mental processes to complete the activity (Vygotsky and Luria 1994).
The Socio-Historical Context Of Learning
The tools available to the individual have been referred to as "socio-cultural technologies" (Rogoff 1989/1991), the selection being largely determined by those used in the immediate cultural environment. In Vygotskian theory learning and development occur within the social context, which is also referred to as the historical domain (Wertsch 1985). The young child experiences acts outside of itself, which are often being carried out in relation to itself. It is the process of assigning meaning to this activity, and of bringing it into voluntary control, which is central to the development of higher mental functions (Vygotsky & Luria 1994). The action is given meaning by the 'adult' involved, (not necessarily an adult per se, but at least a person operating at a higher level of mental functioning). The child does not need to understand the purpose of the activity, or share a common goal with the adult, to take an active part. S/he eventually acquires that meaning as his/her own, but not necessarily in the same form as it was presented. The process of the internalisation of meaning is not one of passive acquisition, of a straightforward transferral of knowledge. Rather it is a process of transformation, with the child being actively involved in re-organising and reconstructing his/her own experiences. An example is provided by the investigations of Vygotsky and colleagues into the contribution of the use of signs to memory tasks (Zankov;
Yssevich; Leont'ev; cited in Vygotsky & Luria 1994). Zankov's tests required the subjects to memorise word lists, with abstract figures provided as potential memory aids. Young children ignored the aids. Older children did use them, but only after transforming the figures into meaningful symbols. Thus if a symbol presented could, through rotation or inversion, be made to resemble the object to which it was attached, only then would it be used. (E.g. a triangle might be used to remember ice-cream cone, but a square would not).
This description of the child as an active learner is similar to that supplied by Piaget in relation to the concepts of assimilation and accommodation (Vygotsky 1934/1986). The difference between the two theoretical approaches arises in the importance attached to the context in which psychological activity occurs. From the Vygotskian perspective child development is a social activity, s/he is not the Piagetian solitary thinker. Thinking develops through social guidance, and is thus moulded and developed, and may even be constrained, by it. That is not to say that the child is only a product of his/her environment. Vygotsky described two equally important roots of development, the natural/biological, and the social/historical. They begin independently, with biological development pre dating the social. As internalisation of the social experiences increases they do not supplant the biological processes. Rather the two become interdependent, creating a qualitatively different potential from that to be expected if they should act independently. The biological influence upon development is not expanded upon in the same detail as the social-historical by Vygotsky himself. It is to the closely related work of his colleague, Luria, that one must turn for a working model of brain functions and the brain - behaviour link.
The Process Of Development
To complete this summary of the Vygotskian description of the social-historical stages of development, it is appropriate to look next at the concept of the Zone of Proximal Development, which, in the words of Minick is;
"the primary locus of change in human psychological development”.
The Zone of Proximal Development, or ZPD, has been defined by Vygotsky as the distance between a child's
"actual developmental level as determined by independent problem solving" and the higher level of " potential development as determined through problem solving under guidance or in collaboration with more capable peers."(Vygotsky cited in Wertsch 1985 p.67).
As an example, take two children whose test performance places them both at the 6 year level. With careful prompting one child succeeds at tasks at the 7 year level, and the other, with the same prompts, at a 9 year level. Their understanding is not therefore at the same level, as was suggested by the first measure.
Tharp and Gallimore presented a four stage model which clearly illustrates transition through the ZPD (Tharp and Gallimore 1988). During Stage 1 performance is assisted by more capable others. Instruction at this stage is characterised by the manipulation of a number of features of the activity by the adult even before the interaction with the child begins. The adult anticipates the level of functioning of the child by adjusting: the choice of the tasks to be given; the selection of tools and materials; and the form of instructions. To solve the problem of finding a missing shoe, for example, the adult may ask the older child "Where did you last remember having it ?". Task analysis would be applied for a younger child, with a series of more directed questions such as " Did you have it in the kitchen?..in the bedroom? etc.". A younger child still would be accompanied on the hunt, with appropriate verbal labels being attached to define the activity being carried out. "Let's look in the kitchen, is it here? etc.".
Modifications and reductions occur in the quantity and quality of help the child requires in order to complete a task, up until the point where, in that domain. Stage 2 in reached. At this point performance has begun to be assisted by the self. The assistance is still external, in that it is accompanied by external verbalisation, such as the child saying to him/herself "Mustn't touch". In support
of the importance of this stage are several sources, many cited in Tharp and Gallimore, indicating that teaching overt self-instruction improves performance particularly in 'impulsive' children (Gaddes & Edgell 1994).
During Stage 3 performance is "developed, automatised and fossilized"
(Tharp and Gallimore 1988). It no longer requires external assistance, and in fact at this stage assistance might even be considered to be disruptive. For example early counting at Stage 2 may be aided by the use of external aids such as fingers or beads. At Stage 3 counting skills will have been internalised to the point where such external aids are longer used. Indeed the imposition of an external system at this level can actually slow down the completion of the activity.
The achievement of independent internally controlled performance is not the final stage however. Learning and development continue in other domains, and during Stage 4 the learner will revert to earlier stages, actively seeking assistance where necessary to master new skills. Although placed later than Stage 3, performance at Stage 4 is characterised by performance at earlier levels. Returning to the example of counting activities, and mental arithmetic, at Stage 4 the child who can now count internally will probably need to return to earlier stages when the problems involve either larger numbers, or other processes, such as subtraction, as well.
What is highlighted by the Tharp and Gallimore model is the dynamic nature of cognitive ability, a concept central to the Vygotskian approach. This has important implications for the assessment of cognitive abilities, and the measurement of levels of development. The concept of the ZPD provides a framework for developing informative assessment tools. In support of its importance and value Vygotsky found through investigation,
"... that the child with the larger zone of proximal development will do much better in school."(Vygotsky 1934/1986 p.187).
Indeed he stated the measurement of the ZPD had more pedagogical value than one session, test only, measures of ability. The measurement of the ZPD will be discussed in more detail in Chapter 10.
Another important theme to be touched on above is the role of instruction in cognitive development. Whilst it is of major importance in guiding development, the reference to the child being actively involved in the internalisation of the use of signs must not be forgotten. It would be erroneous therefore to see the role of instruction as exclusively to pull development behind it, although this may be the case at times.
Thought And Speech
Amongst the signs involved in the development of higher mental functions, language is the most important (Vygotsky 1934/1986). At the point in development where the external operations mediated by language turn inwards, the specific language environment becomes an integral part of the thought processes. A comparison was made between the conceptual categorisation of Native and Anglo Americans by Carrol and Casagrande (1958), which clearly illustrates this. Subjects were required to select the two, out of three, pictures which they judged to be illustrating the same concept. It was hypothesised that the two groups would differ in the pairings made, and that these differences would be attributable to differences in linguistic structure between Hopi and English, the two languages involved. Results supported these hypotheses. For example, where the three pictures portrayed pouring, spilling and dropping, Hopi speakers classified the first two together, and English speakers the last two. In Hopi a distinction is made between dropping objects and liquid, but not between intentional and accidental pouring. Whilst to English speakers the more salient dimension seemed to be the intentionality of the act.
After studying the results of research on apes and humans (Kohler cited in Vygotsky 1934/1986, Vygotsky & Luria 1994), Vygotsky came to the following conclusions about the link between thought and speech/language. Firstly,
thought and speech have different genetic routes, initially developing independently, upon different lines. Early thought is pre-linguistic, and early speech is at a pre-intellectual level. At a later point in development thought becomes verbal and speech rational. When the two lines of development do meet "the nature o f the development Itself changes" (Vygotsky 1934/1986 p.94). One aspect of this relationship can be illustrated by the example of studies of aphasies, carried out by Vygotsky and colleagues (cited in Vygotsky & Luria 1994). The loss of language abilities was found to be associated with fundamental changes in behaviour, particularly evident in an inability to organise and co-ordinate functions in the completion of a task. Language appears to have been an integral part of thought processes, guiding planning and strategies. The impairment of language left the functions required to complete the tasks unimpaired, but the implementation of activity severely disrupted.
The Development of Concepts
Another perspective on the relationship between language/speech and thought, and the changing relationship between the two throughout development, comes from the study of the development of concepts. Vygotsky's description of the development of concepts was based upon experiments carried out in collaboration with Sakharov (cited in Sakharov 1930/1994 and Vygotsky 1934/1986). These experiments consisted of categorisation tasks requiring that wooden blocks, varying in size, colour and shape, be sorted according to concepts fabricated for the study, and labelled with nonsense words. The process by which solutions were sought by adults, adolescents and children was compared. Qualitative differences emerged between children and the other two age groups, in the way objects were categorised, and the way relationships between objects were perceived. In childhood the focus was upon concrete and perceptual similarities between objects. In adolescence, continuing into adulthood, concepts emerged which were abstract and logical. In childhood the process of selection for inclusion into a category was often done on an item by item basis, with each successive item only being compared to the one immediately preceding it. At the earliest stages of development this could lead to
groups of objects where the first and last item possessed no common feature. In early childhood then the nonsense words merely provided a label, but the child's behaviour was not directly guided by any specific meaning attached to that label. Later in development the labels were assigned broad and flexible meaning which directly guided behaviour. Children were thus said to possess "complexes" rather than "concepts", the latter developing only when a more rigid meaning, representing a true understanding of the label, was assigned.