• Social Identity
• Self Regulation
• Aggression and Prosocial Behavior
• Factors Effecting Early Development

INTRODUCTION

Developmental change evolves more slowly in early childhood, the period from 2 to 6 years of age, than in infancy. During this time, children lose their baby fat, their legs grow longer and thinner, and they move around the world with increasing dexterity. They present a bewildering patchwork of vulnerability and ability, logic and magic, insight and ignorance. Children at this age can talk in endless sentences but are keen listeners when an interesting story is being told. Their present desires can be curtailed with promises of later rewards, but they may not necessarily accept the offered terms, negotiating for an instant as well as a delayed reward. They develop theories about everything, and these are constantly measured against the world around them. However, despite their developing independence, 3- year-olds need assistance from adults and siblings. They cannot hold a pencil properly or string a loom or tie a knot. They do not have the ability to concentrate for long periods of time without a great deal of support, and they wander on tangents in their games and conversations. Preschool children's thought processes are characterized by great awareness; yet these islands of sophistication exist in a sea of uncertainty. Children during this period still understand relatively little about the world in which they live and have little or no control over it. They are prone to fears and they combat their growing self-awareness of being small by wishful, magical thinking.

Traditionally, scientists have sorted these changes into separate categories- cognitive, language, physical and social development. Development in each of these areas, however, affects and interacts with every other type. For example, cognitive development creates the need for more sophisticated speech in order to express new knowledge. Language development leads children to master new words that capture new ideas. Physical development allows them to perform more complicated tasks than they could earlier, bringing them into greater social contact with others. The information presented in the following sections discusses some of the major achievements in each of these areas of development.

PHYSICAL, MOTOR, AND PERCEPTUAL DEVELOPMENT

The preschool years are characterized by striking physical and psychological changes. The brain and nervous system grow rapidly and important parts of the brain attain their mature form. The child continues to grow, from an average height of about 33 inches at age 2, to about 45 inches at age 6. Motor skills also improve substantially. During this age children's baby fat disappears, their legs lengthen, accounting for a larger proportion of their height, and the relation of head size to body size becomes more adult-like. As will be discussed in this chapter, physical development of the young child corresponds closely to changes in cognitive, language, and social behaviors.

Physical Development

In general children during the first two years of life quadruple their weight and increase their height by two-thirds. This rate slows down between 2 and 3 years when children gain only about 4 pounds and grow only about 3.5 inches. Between the ages 4 and 6, the increase in height slows still further and children grow about 2.5 inches and gain 5 to 7 pounds on the average. As a result of the slower growth rate following age 2, most 3 and 4 year olds seem to eat less food. While causing alarm in some parents, the change in food intake is normal. Children do not eat less food but rather they eat fewer calories per pound of body weight. The decrease growth rate requires less calories to build their developing muscles, bones, and nerves. Although normal children follow the same growth pattern, there are wide individual variations. A child with a slow growth rate may continue to gain in height and weight until age 20 while a child with a fast growth rate may complete full growth by 16 years of age.

Physical development results from the interaction between individual factors of heredity and environmental forces. Abnormal growth patterns often reflect this interaction. A striking illustration of this effect is the failure to thrive syndrome in which children suffering from prolonged neglect or abuse simply stop growing. In these children, psychological stress produced by their social environment causes the pituitary gland to stop secreting growth hormones. When the environmental stress is alleviated, and the child receives care, affection, and stimulation, growth resumes often at a rate that enables catch-up growth to occur. In body growth, brain growth, and all other aspects of physical and psychological development, genes and environment collaborate to produce normal development. Physical developments are affected by the environment no less than psychological ones. A healthy environment is necessary for normal growth of the body, brain, and nervous system.

The brain continues to grow rapidly during the preschool period. At age 2, the child's brain has reached 55% of its adult size; by six years of age it has grown to more than 90% of its adult size (Tanner, 1978). While brain growth during this period is often uneven, most has occurred before 4 to 4.5 years of age. There appears to be a spurt in growth at age 2 followed by a major decrease in growth rate between 5 and 6 years of age. The increase in brain size reflects changes in the organization and size of nerve cells rather than an increase in the number of cells. The growth also reflects an increase in the number of glial cells that feed and support the nerve cells and to the increasing myelination of nerve fibers. Myelin is the coating around nerve fibers that serves to channel impulses along the fibers and to reduce the random spread of impulses between adjacent fibers, thus helping the nervous system to function quickly and accurately.

In appearance the human brain consists of two symmetrical hemispheres that specialize in different functions. The left hemisphere controls verbal, reasoning, and mathematical skills, while the right hemisphere specializes in nonverbal skills such as spatial ability, perception of patterns and melodies, and the expression and recognition of emotion.

Motor Development

There are significant advances in motor control during the preschool period. These advances depend both on physical maturation of brain and body systems and on the increasing skill that comes through practice. They involve both the large muscles such as those used in running, jumping and climbing, and the small muscles such as those used in drawing and tying a knot. Several factors contribute to the growth in motor development. In the first instance, this development reflects the gradual transition from the reflex behavior of the newborn to the voluntary actions of the preschooler. A second factor is the child's increasing ability to accurately perceive body size, shape and position of its parts. Increasing bilateral coordination, the coordination of the two halves of the body, also contributes to increased motor performance. Virtually every motor skill requires some sort of cooperation between the two sides of the body, moving in some kind of alternatively timed relationship.

The capacity to perform activities as walking, running, and jumping does not necessarily imply the ability to perform them skillfully or smoothly. For example, the young toddler's steps are awkward. Yet by the end of toddlerhood, walking becomes a skilled activity. The stride lengthens, speed increases, balance stabilizes, and the child can walk for long periods without resting. By the age of 4, the child's walk is essentially the same as the adult's. In most cases the development of a motor skill involves the gradual integration of existing movements into a smooth, continuous pattern. In other cases new movements must be acquired. For example learning to throw a ball skillfully involves the integration of existing movements and the acquisition of new ones.

In contrast to large muscle skills, small or fine muscle skills refer to the use of hands and fingers in the manipulation of objects. Also known as eye-hand coordination, fine motor control is the ability to coordinate or regulate the use of the eyes and the hands together in efficient, precise, and adaptive movements. This coordination enables the development of a wide variety of skills including writing, drawing, and the manipulation of small objects and or instruments. Preschool children learn to manipulate objects through visual feedback which indicate whether or not they are doing what the child wants the objects to be doing. Thus the preschool period is an important time for the development of manipulation skills which in turn prepare children to deal successfully with the challenges of primary school.

Differences in motor development are striking and some children are simply better coordinated, stronger and more athletic than others. What accounts for these individual differences which tend to persist throughout the life-span? Genes unquestionably play a role and evidence suggests that identical twins are more alike than fraternal twins in their performance of motor skills during the preschool years. Nutrition is also critical and children who have been undernourished for long period of time are likely to be retarded in their motor development. The capacity to catch up with their better nourished agemates depends on the duration, severity, and timing of the nutritional deficiency. Experience and opportunities to practice both the large muscle and fine muscle skills also contributes to differences in the development and functioning of these skills.

In addition to these factors, there appear to be consistent gender differences in physical development throughout the early childhood period. On the average, girls are physically more mature while boys are physically more muscular. Motor differences are also apparent and boys on the average have larger muscles than girls which enables them to run faster, jump farther, and climb higher. Girls seem to be more advanced in other aspects of motor development particularly in manipulation skills such as using scissors and fastening buttons. They are also ahead in large muscle activities that require coordination rather than strength such as skipping, hopping, and balancing on one foot. Despite these gender differences, there is a striking similarity in the overall pattern of children's physical and psychological development during the preschool years.

Perceptual Development

While the ability to see, hear, and integrate sensory information is well established by six months of age, more complex and less obvious perceptual abilities develop throughout early childhood. For example, precision of visual concepts such as shape and size increases. As a results of these evolving perceptual mechanisms, a child correctly observes an object's size and shape regardless of the angle at which it is perceived. While such mechanisms are present in infancy, they lack accuracy. Infants may know that a distant object takes up less visual field than a closer object, they must learn how much less. This type of learning occurs through active and lively exploration of the environment and is critical in the development of accurate size, shape, and distance perception.

Another aspect of perception often taken for granted is the ability to interpret pictorial representations of objects and people in the environment. Research indicates that 3 year olds respond appropriately to depth cues such as shading and the convergence of lines. Sensitivity to such cues, however, improves with age. The ability to obtain accurate information from pictures reflects children's eye movements fixation patterns. Adults use only leaping eye movements to sweep around the picture as a whole, and short eye movements when concentrating on particular details. By contrast, young preschool children tend to have shorter eye movements and focus their gaze to small areas near the middle or edge thus ignoring or missing much of the information available.

The study of children's art provides some insight into the integration of their growing perceptual, cognitive and motor abilities. The 2.5 year old grasps a crayon in his hand and scribbles while the 4 year old can draw a recognizable human form know as the "tadpole person." The tadpole person is characterized by a big head, sticks for legs, and no body. The transition from drawing scribbles to the tadpole person usually occurs sometime between the 3rd and 4th year. Increased motor control and eye-hand coordination is one of the factors involved in this achievement. Drawing skills undergo a second transition sometime between the 4th and 5th year and the tadpole person is transformed into a complete person with a body as well as a head. Like the preschool child themselves, their art is delightfully full of life, energy, and creativity. According to one psychologist's review

A summit of artistry is achieved at the end of the preschool period... Drawings by youngsters of this age are characteristically colorful, balanced, rhythmic, and expressive, conveying something of the range and the vitality associated with artistic mastery... And the often striking products reinforce a general notion of the child as a young artist--an individual participating in a meaningful way in processes of creation, elaboration, and self-expression. (Gardner, 1980, pg. 11)

COGNITIVE DEVELOPMENT: PARADOXES OF THE PRESCHOOL MIND

For decades, Piaget's descriptions of young children's thinking dominated exploration of the preschooler's mental development. According to Piaget, children's language acquisition reflects their emerging capacity for representational thought. The ways in which children think about the world, however, are still primitive -- dreams come from street lamps, we think with our ears, clouds are alive, and the sun follows us when we move. Piaget proposed that 3-, 4-, and 5- year old children make errors because they are still unable to engage in true mental operations. This type of thinking therefore was termed "preoperational." According to Piaget, the key feature of preschool thinking is that children can only focus their attention on one salient aspect at a time. This limitation is overcome at 6 or 7 years of age, when the transition to concrete operational thinking emerges. When this occurs, children are able to combine, separate, and transform information mentally in a logical manner. They know that the sun does not follow them and dreams do not come from street lamps.

Preoperational intelligence differs in many ways from the thinking of older children and adults and is sometimes puzzling and confusing to parents and caregivers. According to Piaget, preoperational thinking not only lacks logic but it is also egocentric. This kind of self-centeredness is characterized by a 4 year-old's statement; "Look Mommy, the moon follows me wherever I go." Another characteristic is known as complexive thinking, a chaining of ideas in which each is linked to the preceding or following one but the whole is not organized into a unified concept. A third characteristic of preoperational thought is the capacity for deferred imitation which allows children to engage in pretend games.

Representation

The ability to pretend is linked to the capacity for representation-the ability to think about the property of things without having to act on them directly. The development of representation is the cornerstone of all cognitive development during the preoperational period. Recent research suggests that preoperational intelligence develops through at least two distinct levels, single representations which occur between the ages of 2 and 4, and the second between 4 and 6 years when children are capable of combining two or more representations (Case and Khanna, 1981; Gelman 1978; Kenny 1983). The transition from one of these levels to the next corresponds to a spurt in brain development.

Observation of children in pretend play indicates that children at 2 years of age can control only one representation at a time. For example, in making a doll act as a person the child can represent the person doing only one thing at a time- a child walking, a man eating, a woman washing her hands. As the child matures single representations begin to include a set of related characteristics or actions. Children combine characteristics into concrete social categories. For example, the child can make a doctor doll perform a series of doctor activities such as putting on a white coat, washing its hands, taking a temperature and giving an injection.

At about 4 years of age children begin to understand some of the interrelationships and complexities of social behavior. For example, the category man includes as part of its meaning the relation between men and women. Similarly they begin to understand other social relationships such as husband-wife, mother-father, mother-child and so forth. By relating various representations the child now begins to understand relationships in which variation in one facet of development depends upon variation in another. This ability is reflected in the child's new attempts to influence behavior. Strategies such as; "If you let me play with your box, I'll let you play with my bucket," are quite common among 4.5 year olds. The preschool child is concerned with making sense of the people around them and how they relate to each other.

Imitation

Imitation is one of the most important ways children learn about the social world. During the sensorimotor period, before the capacity for representation develops, infants can imitate an action only at the moment it is observed. One result of representation skills is the capacity for deferred imitation-the process by which a child observes represented to themselves, and then at a later time called up from memory and actively imitated. Imitation also requires the ability to take another's point of view. Piaget pointed out that children often make serious mistakes by assuming that another person shares their own view of things. Everyone who has spent time with young children is aware of this egocentrism or the inability to take another's point of view. Even when preschool children are shown another person's perspective, they cannot keep it in mind and coordinate it with their own. They are not selfish but simply captives of their own viewpoint.

As cognitive skills increase, perspective-taking skills improve. At 2 and 3 years of age, children can take someone else's perspective only in the sense that they can understand a characteristic. By 4 and 5 years, children are able to understand the difference between another person's perspective and their own as long as they need to keep track of only one or two simple concrete factors. Thus, by 4 or 5 years of age, most children have taken a major step away from egocentrism.

Memory

In order to understand another's perspective, the child must be able to remember. Memory is the ability to encode information, store it, and retrieve it. There are two kinds of memory, namely short-term and long-term. Short-term, or the working memory, processes information retrieved within a few seconds or minutes of its being encoded. Preschoolers can use both short-term and long-term memory. For example when they have heard a brief list of words or seen a small group of pictures presented by an experimenter, 4-and 5-year-olds can often recall them immediately after presentation as well as older children can. Their long-term memory is often quite amazing.

Early development is characterized by changes in memory that are related to changes in cognitive development including; the increasing ability to focus attention, the ability to connect ideas with each other in a more logical way, and the ability to devise strategies for remembering. Although memory improves throughout childhood, important developmental changes take place during the preschool years. Just as with perspective taking, a major advance in memory abilities seems to begin at about 4 or 5 years when children start to recall items of some complexity and when they begin to monitor and manipulate them own memories.

Play

Preschool children love to play and they spend hours building and knocking down towers, they play house, and act out stories with their playmates. Play in infancy consists mainly of imitations of repeated actions sometimes with variations. In the preschool years, play expands into much of the child's life. Preschoolers love to play games that test and fine-tune their mastery of their bodies-running, climbing, swinging, throwing. They like to build things with mud, sand or blocks and they love to pretend. They make believe about all kinds of things everyday concerns, new things they have learned, and imagined adventure.

During the preschool years, children gradually play less by themselves and more with other children. At 2 years of age, solitary play is common and social interaction with other children remains simple. Parallel play is often observed in 2 year olds and becomes common by age 3. In parallel play a child is influenced by the activities of other children but they do not actually cooperate in accomplishing a task. Both children may be playing with sand and imitating one another's activities, but they are unlikely to work together to build the same castle.

With an increase in thinking abilities, the complexity of children's solitary and social play also increases. At about 4 years of age cooperative play begins to predominate. During this form of play several children will create a city of blocks or play a game in which each child takes the role of a family member and together they act out the daily events. The content of play assumes a new level of understanding and the child begins to play games with simple rules. At any age, children's problems and concerns are reflected in their play. Play provides a time when children can control things themselves.

Piaget's perspective on the preschool child's development places the child at the centre of his or her universe. Through active interaction, exploration, and observation of the environment, the child actively creates his or her own learning. Play facilitates the transition to higher levels of cognitive development; the "as if" nature of play allows children to perform actions that are more developmentally advanced than those they can realistically achieve. Play fosters a sense of self-esteem and competence, supporting and reinforcing the child's capacity for effective action. As a consequence, in play a child is always above daily behaviour; in play "it is as though he were a head taller than himself."

Complex Thinking

Because play is mostly under the child's control, it clearly indicates some of the paradoxes in children's thinking processes. Preschool children usually have difficulty controlling or coordinating their thoughts. Even when they are capable of representational relations, they can deal with only simple, crude connections between ideas, so their thoughts tend to wander. One result of these difficulties is a thought pattern known as complexive thinking--the stringing together of ideas without a unifying concept or system. While there are connections between ideas, a single concept that ties them all together is lacking.

Personification, the attribution of human characteristics to inanimate objects, is often characteristic of children's thinking. Having only recently learned to separate their own actions from those of other people or objects, preschool children are not yet able to distinguish clearly between properties of objects and characteristic of people.

In summary, during the preschool years, many cognitive-developmental changes take place. Before this period, infants do not distinguish between themselves and their actions on the world. Objects exist only when the baby is acting on them or perceiving them. At about age 2 children become capable of representation, of thinking about the properties of things without having to act on them directly. This capacity marks the first level of the preoperational period. At this level, the child can deal with only one representation-one idea or thought at a time. At the second level of the preoperational period, beginning at about age 4, children develop the ability to deal mentally with more complex things. During the preschool years the child moves through these two levels, building increasingly complex and sophisticated schemes. The egocentric, complexive, magical thinking of infancy gradually gives way to more logical thinking-perspective taking, a better memory, and an ability to separate oneself mentally from one's immediate surroundings.

LANGUAGE ACQUISITION

A dramatic accomplishment during this period is the acquisition of language. In late infancy children learn to say a few individual words and, by paying attention to context, they can also understand some of the language used around them. At approximately 2 years of age, their ability to use language suddenly increases rapidly. The size of the vocabulary increases and they begin to string words together in short sentences. The ability to represent objects, people and events through language, develops at about the same time as representation in children's imitation, play and other actions. While representation is not required in uttering simple individual words, it is neccessary for organizing words into simple statements.

Despite intensive research, the process of language acquisition remains elusive, and no single theory has sufficiently uncovered its mystery. What is evident is that the growth of children's vocabulary and their increased ability to use complex sentence structures accompanied by a corresponding growth in their ability to engage in conversation appropriately tailored to the listener's needs, requires both participation in responsive human interactions and exposure to a rich language environment (Bruner, J. 1983). Most research on language development has focused on how children acquire the rules that govern our use of language.

The two types of rules that have been most investigated are pragmatics, rules for communicating in social contexts, and grammatical rules for combining words. Many of the language rules that children learn amount to social conventions and are so automatic for adults that we are not even aware of them. In adult speech, for instance, expressive devices, such as sarcasm, tell the listener not to take what is being said literally. Another device is the use of a question as an indirect request. Because of egocentric thought and social inexperience, young children do not fully understand the indirect requests. For children, the simple pragmatic functions of language are often more important than the specific meanings of sentences. When English speaking preschool children meet in small groups with preschool children who speak another language, they may play together for days without seeming to notice their language differences. An English speaking 4 year old walked up to a French speaking 3 year old and spoke in English. The 3 year old answered in French and they proceeded to play, acting as if they both understood, taking turns, nodding in agreement, and so forth. This interaction emphasized the similarity of pragmatic rules between languages while the meaning of words is generally obvious from the context and from other nonverbal cues such as tone of voice.

Another conversation convention that is beyond the ability of a young preschool child is the rule that what is being said should be interesting to the listener as well as to the speaker. Because children in the early preoperational period are prisoners of their own viewpoint, they think that what interests them interests everyone. This egocentrism leads children to endless self-reporting and the assumption that other people know what they themselves know. They frequently conduct a conversation as though it were a monologue, changing the subject without seeming to be aware of the listener's response. At about 4 years of age, children begin to master some of the more complex pragmatic rules that were so difficult when they were younger. For example, a well-documented developmental change takes place in pragmatic skill with the rules for polite forms of request. To understand what is polite, a child must have the cognitive ability to consider the other person's viewpoint.

Children must also learn the grammar and the rules for forming words, phrases, and sentences. They must be able to express such states and relations as possession, negation, past action and conditional action. One of the most basic concepts is organization of words into sentences. In order to distinguish one sentence from another, each group of words in a sentence has a certain pitch, and stress, so that listeners can distinguish one sentence from the next. English speakers generally drop the pitch at the end of a statement and raise it at the end of questions. Most children recognize and can infer meaning from intonation patterns sometime in the first year of life. This enormous accomplishment reflects the special adaptation of the human species for acquiring language.

How do children learn these complicated rules which are unique for each language? Some psycho-linguistic researchers believe that we inherit species-specific strategies, or operating principles, for perceiving speech. These language operating principles are similar to the newborn's rule for visual scanning. In a similar fashion, young children listen to the language in ways that help to discover its meaning. These strategies for perceiving speech make it easier to understand the rules of speech production. Three important operating principles have helped to explain two of the best known characteristic of children's early speech- telegraphic speech and overregulation (Slobin,1973, 1979). These operating principles include paying attention to the endings of words, paying attention to the order of words and word segments, and avoiding exceptions to language rules.

Telegraphic speech refers to a child's tendency to use only the two or three most important words to express meaning. For example, a child says; "Mommy rice," rather than "Mommy, I would like to have some rice." The average length of sentences steadily increase during the period from 2 to 6 years. Telegraphic speech in different languages has many differences as well as similarities. For example in virtually all languages, children's telegraphic speech is characterized by deletions of certain kinds of words such as articles ("the, a, an), prepositions (in, on, under, through), conjunctions (and, but, because, when) and parts of nouns and verbs that indicate relatively subtle changes in meaning. Since telegraphic sentences are often ambiguous, interpretation often relies on contextual information.

The operating principle of avoiding exceptions to language rules, results in overregularization as children apply a language rule to a word or phrase that does not follow the rule. Statements such as "I goed out and throwed my ball at those gooses" are common from English speaking children at this stage of language development.

Children speaking the same language seem to acquire rules in a similar order. Rules that are simple and used often are acquired first followed by an understanding of and an ability to combine more complex rules. Because the complexity of a given grammatical form differs from one language to another, the age at which children master the rule for a particular form depends partly on the complexity of the language. Some grammatical forms that are not particularly difficult to understand may enter a child's speech late because they are difficult to hear. Because young children can only listen to language, they often make mistakes due to the way a word or phrase sounds.

Preschool children are obsessed with language. They listen to it carefully and chatter away for hours on end. By the age of six or seven they have acquired and mastered most of the rules for speaking in their native language. This amazing feat suggests that there is a critical time, or sensitive period for acquiring language that begins at one or two years of age, peaks in the later preschool years, and continues to some degree until 13 to 15 years of age. This special human sensitivity for learning language in the preschool years seems to correspond to certain systematic changes in the brain and in the rest of the nervous system at about this time, which are closely related to speech. The best documented of these changes are called myelogenetic cycles. Each cycle is a period in which myelin forms in a particular system within the brain. There are three myelogenetic cycles in the system that are important to language (Lecours, 1975). The first cycle, which occurs in the primitive brain (the brain stem and the limbic system) starts before birth and ends early in infancy. It seems to be associated with the development of babbling. The second cycle, which begins around birth and continues until 3.5 to 4.5 years of age, takes place in a more advanced part of the brain. This cycle appears to accompany the development of speech in infancy and the early preschool years. The third cycle takes place in the association areas of the cortex of the brain, which play a central role in intelligence. Although myelination of these areas begins at birth, it is not fully completed until age 15 or later.

Language develops very efficiently for the great majority of children. Parents and caregivers can help sustain natural language development by providing environments full of language development opportunities. With young children, for example, one helpful style of interaction is a highly responsive one, in which the adult lets the child decide what to talk about, expands on that topic, works hard to figure out what the child means, suggests new activities, and pays more attention to what the child wants to say than whether it is being said correctly. An optimal language teacher assumes the role of a cooperative conversational partner rather than taking an explicitly didactic or directive role.

The studies on which this picture is based have mostly been carried out in middle-class, English speaking families, a cultural group within which responsive, nondirective, child centered parenting is considered desirable. In this group children and adults have relatively equal social status, and children are expected from a very early age to function as conversational partners (Cazden, 1988; Snow, 1989).

In other cultures, the rules governing parent-child interaction and parental roles are quite different. In Samoa, for example, social status is closely connected to age, and the idea of engaging a child in conversation as a social equal would seem unnatural. Among the Kaluli of Papua, New Guinea, it is considered better to ask children to talk as adults about adult matters than to "descend to their level" in talking to them. In these cultures we would not expect the responsive style of talk that facilitates language acquisition for American children to function similarly.

Language teaching is most useful to young children when it is presented in the context of their own activities and attempts at expression. Older preschool children, however, can use language to learn language and they no longer need to encounter each new language skill within a meaningful context. Furthermore, they become increasingly capable of learning intentionally, of attending to and benefitting from explicit instruction, and of using models as sources of learning. At this stage simply responding to the child's interests might not be sufficient to stimulate optimal language development. Talking about a wide variety of topics, modelling an enriched vocabulary, engaging in talk about talk itself, discussing word meanings, challenging children to explain themselves and to justify their own thinking, setting higher standards for comprehensibility, and explicitly correcting errors: all these are important in the language development of 4, 5, and 6 year old children. Children at this age range are also expected to control certain language-related literacy skills that probably emerge from being read to, from experience in looking at books with adults, and from experience with letters, with pencils and paper, and with observation of adult literacy activities. Parents and other caregivers foster such skills when they can organize the environment to provide and encourage the use of pre-literacy learning materials.

SOCIAL AND EMOTIONAL DEVELOPMENT

Social development is a two-sided process in which children become increasingly integrated into the larger social community as distinct individuals. The process of acquiring the standards, values, and knowledge of communities and society is known as socialization. The way in which individual children develop a characteristic sense of themselves and a unique way to think and feel is known as personality formation (Damon, 1983). Socialization which begins as soon as a child is born is especially important during early childhood as the first understanding of the child's community is constructed. It is a process that requires the active participation of both adults and children. Caregivers set expectations for children's proper behavior as well as the rewards or punishments for their conduct. Caregivers also select and create the social contexts within which children experience their environments and learn the rules of behavior. Children are active participants in this process. What they learn depends in part on their interpretation of their environments and on what they select as important from the barrage of available information.

Children need to understand the social categories, roles, rules and expectations of their families and communities in order to function in a social world. Effective socialization assures that if a child comes to consider herself a girl, she will acquire the appropriate behavior for girls as defined by a particular social group. In order to understand the requirements of this role, however, she must have certain skills and abilities.

For each child, the combination of characteristics that shape personality is unique since the particular mix of genetic endowment and personal experience is never completely shared with another human being. Some elements of personality are obvious immediately after birth as when infants display a particular temperament. Personality is more than individual temperament as it includes the way people conceive of themselves and their characteristic style of interacting with others.

Thus individual personality development and socialization are two sides of a single developmental coin. Social development during the preschool years is closely linked to achievements in cognitive and linguistic skills. All the feedback received from the social environment is crucial to development of a sense of self. One of the most remarkable facts about social development is the extent to which children adopt as necessary the rules defined by their social group. By the time children reach their 6th birthday a great deal has been learned about the roles they are expected to play and how to behave in accordance with them, how to control anger and aggressive feelings, and how to respect the rights of others. How does all this learning take place and what are the elements that enter into it?

Social Identity

While psychologists agree that socialization occurs by identification -- a psychological process that contributes to a sense of who one is and who one wants to be -- they disagree about the mechanisms by which it is achieved. Four proposed mechanisms have figured most prominently in our understanding of this basic process: differentiation, affiliation, imitation and social learning, and cognition. According to Freud, children recognize that some objects in the external world are like themselves and they therefore "endeavor to mold the ego after one that had been taken as a model." In other words, having noticed that a particular adult or older child is somehow similar to themselves, children "identify with" that person and strive to acquire his or her qualities. Identification follows a different course for males and females. Male identification requires differentiation from the mother, while female identification requires continued affiliation with the mother.

Social learning theorists have a different perspective on how children identify and adopt adult roles. According to their beliefs, the process of identification is not driven by inner conflict but occurs through observation and imitation. Behavior in their view is shaped by the environment and children observe that male and female behavior is different. Further, children learn that boys and girls are rewarded differently and choose to behave in sex-appropriate behaviors that will lead to rewards. Thus the basic assumption of social-learning theorists is that sex-appropriate behaviors are shaped by the distribution of rewards and punishments in the environment.

The belief that a child's ability to perceive the world is central to socialization is the basis of the cognitive-developmental approach to sex-role acquisition proposed by Lawrence Kohlberg (1966). In this view the crucial factor in sex-role identification is the child's developing ability to categorize themselves as "boys" or "girls." This process begins at about 2 years of age as children acquire a distinctive sense of self and the beginning of complex concepts. According to this viewpoint, once formed, children's conceptions of their own sex are difficult to reverse and are maintained regardless of their social environments.

In an attempt to address these conflicting theories about sex-role identification, psychologists have sought to trace the developing relationship between the earliest signs of sex-typed behavior and children's earliest concepts of what adults mean when the label "girl" or "boy" is applied. The existing evidence suggests that during the preschool years children gradually develop a well-articulated concept of what it means to be a boy or girl in their culture and their behavior is shaped by this knowledge. Between 2 and 6 years children are still piecing this conceptual structure together. Both biological and social factors seem to play important roles in promoting both sex-appropriate behaviors and the development of basic sex-role categories themselves.

While developmental theorists disagree about the caregivers's power to shape final outcomes, they do agree on two points concerning the children's discovery of social categories and initial mastery of behavior appropriate to their sex and include: (1) children conduct some kind of mental "matching" operation that allows them to isolate key features that they share with others; (2) later ideas of sex-appropriate behavior are closely tied to children's ability to categorize, observe, and imitate. By whatever route, children of 5 or 6 have acquired the idea that they are members of one sex or the other. Children use these abilities to learn a vast array of other roles and about the possible roles they may play in the future.

Self Regulation

In the process of acquiring a basic sense of identity, children also learn which behaviors are considered good and those that are considered bad. They are expected not only to learn and adopt the rules of proper behavior, but also to follow these rules without constant supervision. Piaget proposed that children's beliefs grow out of their experience of the restriction placed on them by powerful adults. From the child's perspective, older people announce the rule, compel conformity, and decide what is right and wrong. According to Piaget as children enter middle childhood and begin to interact with their peers outside of situations directly controlled by adults, the morality of constraint gives way to a more autonomous morality--one that is based on an understanding that rules are arbitrary agreements to be challenged and even changed, if those governed by them agree.

By the end of infancy children are sensitive to society's standards of good and bad and can begin to anticipate adults' reactions and plan their own actions accordingly. Internalization of adult standards occurs when children both want to conform to adult standards and can anticipate their reactions. In order to behave according to social standards, children must acquire the capacity to control their own behavior. Self-control includes both the ability to inhibit action and to carry through actions according to preestablished rules even when one does not wish to do so. Preschoolers are well known for their lack of self-control and the consequent need for supervision. In so far as behavior is simply a direct response to the environment, they are being controlled "from the outside." The direct response to being hit is to be angry and hit back. Children who inhibit the impulse to hit back and seek an alternative response are displaying a degree of self-control. Young children's growing ability to estimate the tradeoffs implied by a change from direct, immediate reactions to indirect, mediated, thoughtful ones is made possible in part by their expanding time frame and their increased understanding of the proper forms of behavior. Children who do not understand short-term versus long-term cannot measure "short-term" versus "long-term" gain.

During the preschool period children begin to spend significant amounts of time interacting with their peers. Through this process children must learn to be accepted by their social group. In so doing they must at times inhibit their anger when their goals are thwarted; at other times their personal desires will be subordinated for the good of the group. Learning to control aggression and to help others are two of the central processes in preschool social development.

Aggression and Prosocial Behavior

Shortly after birth, children begin to display the beginnings of both aggression and socially constructive behavior. The earliest signs of aggression are the angry responses of newborns when their rhythmic sucking has been interrupted. The first signs of helpful social behavior appear just as early when newborns reacting to the cries of other babies start to cry themselves. It is believed that this contagious crying is the earliest form of empathy, sharing of another's feelings which is the foundation for a variety of helpful or prosocial behaviors.

Although aggression is a behavior difficult to define, it generally refers to situations where one person commits an action that hurts another. As children mature, two forms of aggression are apparent, namely instrumental aggression and hostile aggression. Instrumental aggression is directed at obtaining something desirable, such as threatening or hitting another child to obtain a wanted object. Hostile aggression is more specifically aimed at hurting another, either for revenge or as a way of establishing dominance. Observations across a variety of cultural settings suggest that by 2 years of age children are concerned with ownership rights. The possession itself as well as the possibility of winning were new elements in their interactions. Between 3 and 6 years, the expression of aggression undergoes several other related changes. While physical tussles over possessions decrease, the amount of verbal aggression such as threats or insults increases. During this stage, person-oriented or hostile aggression where one child attempts to hurt another also appears.

It is a commonly held assumption that punishment suppresses children's aggressive behavior. Some child development specialists argue that parents who control children's behavior through physical punishment or threats of raw power actually create more aggressive children. Others have suggested that when punishment is used as a means of socialization, it is most likely to suppress aggressive behavior when the child identifies strongly with the person who does the punishing and when it is employed consistently. If punishment is used inconsistently, it may provoke children to further aggression. Since young children use aggression to gain attention, one strategy is to ignore the aggression or to pay attention to children only when they are engaged in cooperative behavior. Another strategy is engage children in a rational discussion making them aware of the feelings of the aggressed. In spite of the diversity of these strategies, the most successful techniques for teaching self-control of aggression go beyond mere suppression of aggressive impulses. Rather, children are requested to stop their direct attacks and consider other ways to behave.

In addition to aggressive behaviors, prosocial behaviors such as altruism, cooperation, and empathy are common among preschool children. A major stimulus for prosocial behavior is empathy, the sharing of another's emotional response. Although infants seem to be born with an ability to empathize, like other developmental tasks, this capacity increases with age. Preschool children become skilled at interpreting and responding appropriately to the distress of others. Research seems to suggest that the development of empathy in the preschool period results from the child's increasing command of language and other symbols (Hoffman, 1975). Language allows children to empathize with a wider range of feelings that are more subtly expressed, as well as with people who are not present. Indirect information gained through stories and pictures enables children to empathize with people they have never met.

Caregivers, anxious to encourage prosocial behavior, have developed many commonly used strategies to promote this goal. Two methods that seem to be helpful include explicit modeling in which adults behave in ways they desire the child to imitate, and induction, giving explanations that appeal to children's pride, their desire to be grownup and their concern for others. In reality, strategies to increase prosocial behavior do not occur in isolation from efforts to decrease aggressive behavior. Rather a great variety of techniques are likely to occur in combination with each other, and in the process a diversity of socialization patterns is created.

Factors Effecting Early Development

Theories of child development are challenged by the variation in preschool children's thinking. For some, the unevenness can be explained by differences in children's familiarity with specific task settings. Biologically oriented theorists argue that changes in the brain's structure are the major cause of unevenness in preschool thought. At the start of the preschool period, the brain has achieved 50 percent of its adult weight. By the age of 6, the brain will have grown to 90 percent of its weight. Within this overall process of growth, myelination -- the process by which neurons become covered by myelin, which is a sheath of fatty cells that stabilizes the neurons -- appears to play a particularly important role in preschoolers' cognitive development.

In light of these varying perspectives, the position most reasonable to accept, however, is that the context-specific organization of the child's environment is constantly interacting with the biological properties of the child, which themselves develop at different rates. Appreciating the immense variation of these two diverse sources, one from the social world of human existence and one from biology, we can begin to understand the range and variability that characterizes development of the preschool child. In this ecological view of development, the child's environment consists of four interrelated systems which include the nuclear and extended family; the immediate community of peers and neighbors; the institutional community of schools and other social service facilities; and a cultural ethos consisting of values, beliefs, and rituals. The child's development is conditioned by the frequency and complexity of interactions within each one of these systems. For example, cognitive and social development seem to be most affected by factors of the home environment, including the caregivers' self-image, self-esteem, confidence, and emotional responsivity; the restrictions and types of discipline imposed on the child; the language stimulation provided; and the child's opportunities for exploratory play and appropriate play materials. Factors in the immediate community impacting on the child's development may consist of community attitudes, beliefs, and perceptions regarding the ideal child and childrearing patterns that foster such development.

Until recently, emphasis was placed on identifying and overcoming deficiencies of the "deprived" environments that characterized the rural and urban poor. Disadvantaged environments have been thought to lack the necessary variety and quality of human interactions as well as the necessary objects and events for fostering a child's early development. Poor quality verbal interaction and absence of toys and were frequently cited as detrimental to a child's language abilities and visual-discrimination. More recently, however, the strengths of the environments characterizing the poor which are capable of fostering and promoting early development have been appreciated. Such features include, for example,

• Opportunities for play with peers and older children with minimal adult interference enhancing the development of self-reliance, self-control, cooperation, empathy and a sense of belonging.
• Exposure to multiple teaching styles, with emphasis on modeling, observation, and imitation.
• Presence of a rich cultural tradition of games, toys, songs, and stories that provide a culture-specific context for language acquisition.

Realization is growing that within so-called deprived environments, children learn a different set of skills that are functional in their home environments but that may not be valued by formal institutions such as the school system. In the design of culturally appropriate, community-based early intervention programmes, it is critical therefore, to explore, mobilize, and build on these inherent strengths. The recognition of strengths within "deprived" environments sheds light on the factors giving rise to "invulnerable," or stress-resistant, children.

Past investigations that focused only on vulnerabilities and sources of failure prevented an understanding of the ways in which protective mechanisms shield children from risk. In the past decade, efforts to understand "invulnerable" children have begun. Garmezey has proposed three categories of protective factors, which include (1) personality characteristics of the child; (2) a supportive, stable, and cohesive family unit; and (3) external support systems that enhance coping skills and project positive values.

Recently, investigators have identified the child's "sense of self" as a key determinant of successful outcomes. It is suggested that children with positive feelings of self-esteem, mastery, and control can more easily negotiate stressful experiences. These children in turn elicit more positive experiences from their environment. They show initiative in task accomplishment and relationship formation. Even in stressed families, the presence of one good relationship with a parent reduces psychosocial risk for children. For older children, the presence of a close, enduring relationship with an external support figure may likewise provide a protective function. A child with a positive self-concept seeks, establishes, and maintains the kinds of supportive relationships and experiences that promote successful outcomes. These successes enhance the child's self-esteem and sense of mastery, which leads to further positive experiences and relationships. The cycle of success can be as self-perpetuating as the cycle of failure.

In spite of these strengths, it is clear that the developmental costs of poverty are high and that poverty is a marker for potential psychosocial risk factors. Children in poverty are exposed more frequently to a clustering of such risk factors as medical illness, poor nutrition, family stress, low education levels, inadequate social-service support, and nonstimulating social environments. The costs can be measured in terms of school drop-out, unemployment, delinquency, and the intergenerational perpetuation of failure and poverty.

These stress factors additionally or "synergistically" interact with the child's inherent strengths and vulnerabilities to shape outcomes. A transactional model developed by Sameroff and Chandler has become widely used to help define developmental outcomes. According to this framework, child outcomes can only be interpreted by considering the transaction between the content of the child's behaviour and the context in which the behaviours are manifested. Characteristics of the child shape its response to the environment. These interactions in turn transform environmental responsivity. Just as the child is shaped by the environment, so is the environment modified by the child. The child brings a host of attributes to the interaction, including; health and nutritional status; temperament; and cognitive, language, and social skills. The environment in turn brings specific attributes. In an environment of poverty, more risk factors are likely to be present. While adding considerable complexity to the determinates of child outcomes, such a model also suggests an opportunity for practical intervention strategies. Change in any aspect of the child's differing environments can create positive transformations in another.

The period of early childhood ends at the age of 6 or 7 years, when children pass through the next biobehavioural shift and assume the accompanying social roles and demands. Generally by this age, children's brains have achieved a level of complexity similar to adults. It is the age of formal schooling, and children also gather with friends and peers beyond the family. Developments in early childhood provide the essential preparation for the new demands and opportunities to come.

In bringing this theoretical discussion to a close, it is perhaps useful to conclude with the insight of a proverb, "As the twig is bent, so grows the tree." If forces in the environment bend a sapling long enough, the tree may become so bent that its leaves cannot receive the sun's light, and it will not flower and reproduce. Yet, if the forces bending the tree cease or if a gardener stakes the tree upright, the only lasting effect may be a slight bend in the trunk. The tree will prosper and make a genuine contribution to its environment.