Infancy 2022 PDF - Past Paper

CHAPTER 4: INFANCY Neonatal period The first four weeks of life, the neonatal period, is a time of transition from the uterus, where a fetus is supported entirely by the mother, to an independent existence. What are the physical characteristics of newborn babies, and how are they equipped for this...

CHAPTER 4: INFANCY Neonatal period The first four weeks of life, the neonatal period, is a time of transition from the uterus, where a fetus is supported entirely by the mother, to an independent existence. What are the physical characteristics of newborn babies, and how are they equipped for this crucial transition? Size and Appearance: An average newborn, or neonate, in the US is about 20 inches long and weighs about 71/2 pounds. At birth, 95% of full term babies weigh between 51/2 and 10 pounds and are between 18 and 22 inches long. Boys tend to be slightly longer and heavier than girls, A first born is likely to weigh less at birth than later borns. In their first few days, neonates lose as much as 10% of their body weight, primarily because of a loss of fluids. They begin to gain weight again at about the 5th day and are generally back to birthweight by the 10th to the 14th day. New babies have distinctive features: a. Large head (1/4th of body length) b. Receding chin (which makes it easier to nurse) c. Long and misshapen head (because of the ‘molding’ that eased its passage through the mother’s pelvis): This temporary molding was possible because an infant’s skull bones are not yet fused; they will not be completely joined for 18 months. The places on the head where the bones have not yet grown together - he soft spots, or fontanels – are covered by a tough membrane. d. Pinkish cast (this is because their skin is so thin that it barely covers the capillaries through which blood flows) e. Lanugo: Many neonates are very hairy because of the lanugo (fuzzy prenatal hair) which has not yet fallen off. f. Vernix caseosa: All neonates are covered with vernix caseosa (cheesy varnish), an oily protection against infection that dries within the first few days. g. Witch’s milk: This is a secretion that sometimes issues from the swollen breasts of both female and male newborns. This was believed to have special healing powers in the Middle Ages. Like the blood tinged vaginal discharge of some baby girls, this fluid emission results from high levels of the hormone estrogen, which is secreted by the placenta just before birth. Body Systems: Before birth, the fetus’s blood circulation, respiration, nourishment, elimination, and temperature regulation are all accomplished through its connection with the mother’s body. After birth, infants must perform these functions on their own. The transition from intrauterine life to life on the outside makes major demands on all body systems.  1. Circulatory System: Before birth, mother and baby have independent circulatory systems and separate heartbeats; but the fetus’s blood is cleansed through the umbilical cord, which carries blood to and from the placenta. At birth, the bay’s own circulatory system must operate on its own. A neonate’s heartbeat is still fast and irregular, and blood pressure does not stabilize till about the tenth day of life. 2. Respiratory System: The fetus gets oxygen through the umbilical cord, which also carries away carbon dioxide. The newborn, who needs much more oxygen, must now get it independently. Most infants start to breathe as soon as they emerge into the air. A baby who is not breathing within 2 minutes after birth is in trouble; if breathing has not begun in 5 minutes or so, some degree of brain injury from anoxia (lack of oxygen) may result. Infants’ lungs have only 1/10th as may air sacs as adults; thus infants are susceptible to respiratory problems. 3. Gastrointestinal System: The fetus relies on the umbilical cord to bring food and carry body wastes away. The newborn has a strong sucking reflex to take in milk and has gastrointestinal secretions to digest it. Meconium (stringy, greenish black waste matter formed in the fetal intestinal tract) is excreted during the first two days or so after birth. When the neonate’s bowels and bladder are full, the sphincter muscles open automatically. Many months will pass before the baby can control these muscles. Three or four days after birth, about half of all babies – and a larger proportion of babies born prematurely – develop physiological or neonatal jaundice: their skin and eyeballs look yellow. This kind of jaundice is caused by the immaturity of the liver; usually it is not serious and has no long-term side effects. In some cases it is treated by putting the baby under fluorescent lights. 4. Temperature Regulation: The layers of fat that develop during the last months of fetal life enable healthy full-term infants to keep their body temperature constant despite changes in air temperature. Newborn babies also maintain body temperature by increasing their activity in response to a drop in air temperature. A comparison of Prenatal and Postnatal life Characteristic Prenatal life Postnatal life Environment Amniotic fluid Air Temperature Relatively constant Fluctuates with atmosphere Stimulation Minimal All senses stimulated by various stimuli Nutrition Dependent on mother’s blood Dependent on external food and functioning of digestive system Oxygen supply Passed from maternal blood Passed from neonate’s lungs to stream via placenta pulmonary blood vessels Metabolic elimination Passed into maternal Discharged by skin, kidneys, bloodstream via placenta lungs and gastrointestinal tract. States of Arousal: Throughout the day and night, newborn infants move in and out of six different states of arousal, or degrees of sleep and wakefulness which are described below: Daily States Description Duration in Newborns Regular sleep The infant is at full rest and shows little or no body 8 – 9 hours activity. The eyelids are closed, no eye movements occur, the face is relaxed, and breathing is slow and regular. Irregular sleep Gentle limb movements, occasional stirring, and facial 8 – 9 hours grimacing occur. Although the eyelids are closed, occasional rapid eye movements can be seen beneath them. Breathing is irregular. Drowsiness The infant is either falling asleep or waking up. The body Varies is less active than in irregular sleep but more active than in regular sleep. The eyes open and close; when open, they have a glazed look. Breathing is even but somewhat faster than in regular sleep. Quiet alertness The infant’s body is relatively inactive. The eyes are open 2 – 3 hours and attentive. Breathing is even. Stretching. Active The infant shows frequent bursts of uncoordinated motor 2 – 3 hours alertness activity. Breathing is very irregular. The face may be relaxed or tense and wrinkled. Leg cycling Crying Waking activity often involves crying, which is 1 – 2 hours accompanied by diffuse, vigorous motor activity. Sudden Infant Death Syndrome (SIDS): Sudden Infant Death Syndrome (SIDS), sometimes called ‘crib death’, is the sudden death of an infant under 1 year of age in which the death remains unexplained after a thorough investigation that includes an autopsy. It is the leading cause of death in infants after the neonatal period; it occurs most often between 1 and 4 months of age. Causes of SIDS: An underlying biological defect may make some infants vulnerable, during a critical period in their development, to certain contributing or triggering experiences, such as exposure to smoke, prenatal exposure to caffeine, or sleeping on the stomach. A gene that helps regulate heart rhythm, and a defect in liver enzymes have been linked with small percentages of SIDS cases. There are certain chemical receptors, or nerve endings, in the brain stem, which receive and send messages that regulate breathing, heartbeat, body temperature, and arousal. Defects in these receptors (which may originate in fetal life) may prevent SIDS babies from awakening when they are breathing too much stale air containing carbon dioxide trapped under their blankets. This is more likely to happen when the baby is sleeping face down.  Many SIDS babies may be deficient in a protective mechanism that allows an infant to become aroused enough to turn the head when breathing is restricted. Risk factors in SIDS: There is a strong relationship between SIDS and sleeping on the stomach. Side sleeping is not safe either, as infants put to bed on their sides often turn onto their stomachs. Infants should not sleep on soft surfaces, such as pillows, quilts, sheepskin, or under loose covers, which, especially when the infant is face down, may increase the risk of overheating or rebreathing (breathing the infant’s own waste products). Urban African American babies are more at risk for SIDS as they were less likely to be correctly advised about sleeping position in the hospital after delivery. In cultures where bed sharing is a common practice, its possible role in preventing (Those who sleep together tend to wake each other up during the night. This may prevent the baby from sleeping too long and too deeply and having long breathing pauses that might be fatal. Also by snuggling up together, mother and baby stay oriented toward each other’s subtle bodily signals or promoting SIDS (Maternal smoking or drug use, or rolling over of the mother onto the infant promotes SIDS) is controversial. Medical and behavioural assessment: The first few minutes, days, and weeks after birth are crucial for development. It is important to know as soon as possible whether a baby has any problem that needs special care. The Apgar Scale: One minute after delivery, and then again five minutes after birth, most babies are assessed using the Apgar Scale. The Apgar Scale: Sign 0 1 2 Appearance Blue, pale Body pink, Entirely pink (color) extremities blue Pulse Absent Slow (below 100) Rapid (over 100) (heart rate) Grimace No response Grimace Coughing, sneezing, (reflex irritability) crying Activity Limp Weak, inactive Strong, active (muscle tone) Respiration Absent Irregular, slow Good, crying (breathing) Each sign is rated in terms of absence or presence from 0 to 2; highest overall score is 10. Its name, after its developer, Dr. Virginia Apgar (1953), helps us to remember its five subtests: 1. Appearance (color) 2. Pulse (heart rate) 3. Grimace (reflex irritability) 4. Activity (muscle tone) 5. Respiration (breathing) In non-white children, color is assessed by examining the inside of the mouth, the whites of the eyes, the lips, palms, hands, and soles of the feet. The newborn is rated 0, 1, or 2 on each measure, for a maximum score of 10. A 5 minute score of 7 to 10 (achieved by approximately 98.6% of babies born in the US in 2000) indicates that the baby is in good to excellent condition. A score below 7 means the baby needs help to establish breathing A score below 4 means the baby needs immediate life saving treatment. If resuscitation is successful, bringing the baby’s score to 4 or more at 10 minutes, no long term damage is likely to result In general, Apgar scores reliably predict survival during the first month of life. However, care must be taken in interpreting the results. A low Apgar score does not necessarily indicate anoxia. Prematurity, medication given to the mother, and other conditions may affect the results. Newborn Reflexes: A reflex is an inborn, automatic response to a particular form of stimulation. Reflexes are the neonate’s most obvious organized patterns of behaviour. Some newborn reflexes: Age of Adaptive Reflex Stimulation Response Disappearance Function Stroke cheek near Head turns 3 weeks (becomes Helps infant find corner of mouth towards voluntary head the nipple Rooting stimulation turning at this time) Place finger in infant’s Infant sucks Permanent Permits feeding Sucking mouth finger rhythmically Place infant face down Baby paddles and 4-6 months Helps infant Swimming in pool of water kicks in survive if dropped swimming motion into body of water Shine bright light at Infant closes Permanent Protects infant Eye blink infant’s eyes or clap eyelids quickly from strong hands near head stimulation Prick sole of foot with Foot withdraws, Weakens after ten Protects infant Withdrawal pin with flexion of days from unpleasant knee and hip tactile stimulation Stroke sole of foot Toes fan out and 8-12 months Unknown Babinski from toe toward heel curl as foot twist in Hold infant Infant makes an 6 months In human horizontally on back ‘embracing’ evolutionary past, and let head drop motion by arching may have helped slightly, or produce a back, extending infant cling to Moro sudden loud sound legs, throwing mother against surface arms outwards, supporting infant and bringing them in toward the body Place finger in infant’s Infant grasps 3-4 months Prepares infant Palmar grasp hand and press against adult’s finger for voluntary palm grasping While baby lies on Infant assumes a 4 months May prepare back, turn head to one ‘fencing’ position; infant for side onearm is voluntary extended in front reaching Tonic neck of eyes on side to which head is turned, other arm is flexed Body Rotate shoulder or hips Rest of body turns 12 months Supports postural Righting in same direction control Hold infant under arms Infant lifts one 2 months Prepares infant and permit bare feet to foot after another for voluntary Stepping touch a flat surface in stepping walking response Adaptive value of Reflexes: Like breathing and swallowing, some newborn reflexes have survival value. These are called primitive reflexes such as sucking, rooting for the nipple and the Morro reflex. For example, the rooting reflex helps the infant find the mother’s nipple. Imagine if sucking was not automatic, it is unlikely that our species would have survived a single generation. The swimming reflex helps a baby who is accidentally dropped into a body of water stay afloat, increasing the chances of retrieval by the caregiver. Some primitive reflexes may be part of humanity’s evolutionary legacy. One example is the grasping reflex, by which infant monkeys hold on to the hair of their mother’s bodies. A few reflexes probably were adaptive during our evolutionary past but no longer serve any special purpose. For example, the Moro or ‘embracing’ reflex is believed to have helped infants cling to their mothers during the time when babies were carried about all day. As the higher brain centers become active during the first two to four months, infants begin to show postural reflexes: reactions to changes in position or balance. For example, infants who are tilted downward extend their arms in the parachute reflex, an instinctive attempt to break a fall. Locomotor reflexes, such as the walking and swimming reflexes, resemble voluntary movements that do not appear until months after the reflexes have disappeared. Other reflexes protect infants from unwanted stimulation. For example, the eye blink reflex helps shield the baby from intense bright light. At times, reflexive behaviour can reduce infant distress. As any new mother who remembers to bring a pacifier on an outing with her young baby knows, sucking will reduce the mass, uncoordinated activity of a fussy neonate almost immediately. Finally, several reflexes help parents and babies establish gratifying interaction as soon as possible. An infant who searches for and successfully finds the nipple, sucks easily during feedings, and grasps when her hand is touched encourages parents to respond lovingly and increases their sense of competence as caregivers. Most of the early reflexes disappear during the first six months to one year. Reflexes that continue to serve protective functions – such as blinking, yawning, coughing, gagging, sneezing, shivering, and the pupillary reflex (dilation of the pupils in the dark) - remain. Disappearance of unheeded reflexes on schedule is a sign that motor pathways in the cortex have been partially myelinated, enabling a shift to voluntary behaviour. Thus we can evaluate a baby’s neurological development by seeing whether certain reflexes are present or absent. Reflexes and the Development of Motor skills: Most newborn reflexes disappear during the first 6 months of life, due to a gradual increase in voluntary control over behaviour as brain matures. The fact that babies adapt their reflex actions to changes in stimulation immediately after birth suggests that many reflexes form the basis of purposeful behaviours. For example, different finger movements appear in the palmar grasp reflex, depending on how the palm of the hand is stimulated. Similarly, newborn infants quickly adjust the force with which they suck on a nipple, based on how much pressure is required to get the milk. Certain reflexes drop out in early infancy, but the motor functions involved seem to be renewed later in development. Examples are the palmar grasp, swimming, and the stepping responses. In a well known experiment, babies given daily stimulation of the stepping reflex during the first two months not only retained the reflex, but walked on their own several weeks earlier than infants not given this practice. The importance of assessing newborn reflexes: Paediatricians test infant reflexes carefully, especially if the infant has experienced birth trauma, because reflexes provide one way of assessing the health of the baby’s nervous system. In brain damaged infants, reflexes may be weak or absent, or in some cases exaggerated and overly rigid. Brain damage may also be indicated when reflexes persist past the point in development when they should normally disappear. However, individual differences in reflexive responses exist that are not cause for concern. Assessment of newborn reflexes must be combined with other observations of the baby to accurately distinguish normal from abnormal central nervous system functioning. Moulding the Brain: The Role of Experience The brain growth spurt that begins at about the third trimester of gestation and continues until atleast the fourth year of life is important to the development of neurological functioning. Smiling, babbling, crawling, walking, and talking – all the major sensory, motor, and cognitive milestones of infancy and toddlerhood – are made possible by the rapid development of the brain, particularly the cerebral cortex. Until the middle of the twentieth century, scientists believed that the brain grew in an unchangeable, genetically determined pattern. This does seem to be largely true before birth. But it is now widely believed that the postnatal brain is ‘molded’ by experience. This is so especially during the early months of life, when the cortex is still growing rapidly and organizing itself. The technical term for this malleability, or modifiability, of the brain is plasticity. Early synaptic connections, some of which depend on sensory stimulation, refine and stabilize the brain’s genetically ‘wiring’. Thus early experience can have lasting effects on the capacity of the CNS to learn and store information. Early abuse or sensory impoverishment may leave an imprint on the brain. In one classic experiment, kittens fitted with goggles that allowed them to see only vertical lines grew up unable to see horizontal lines and bumped into horizontal boards in front of them. This did not happen when the same procedure was carried out with adult cats. Apparently, neurons in the visual cortex became programmed to respond only to lines running in the directions the kittens were permitted to see. Thus, if certain cortical connections are not made early in life, and if no further interventions occur, these circuits may ‘shut down’ forever. Early emotional development, too, may depend on experience. Infants whose mothers are severely depressed show less activity in the left frontal lobe, the part of the brain that is involved in positive emotions such as happiness and joy, and more activity in the right frontal lobe, which is associated with negative emotions. Plasticity continues throughout life as neurons change in size and shape in response to environmental experience. Sometimes corrective experience can make up for past deprivation. Brain-damaged rats, when raised in an enriched setting, grow more dendritic connections. Such findings have sparked successful efforts to stimulate the physical and mental development of children with Down syndrome and to help victims of brain damage recover function. (Read Pg 136 Papalia, natural experiment on the effects of environmental deprivation or enrichment of human infants) Language Development Although both maturation and environment are important in the development of language, different linguists assign major importance to one or the other of these factors. Learning theory holds that learning (including learning of language) is based on experience Nativism maintains that there is an inborn capacity for learning language. Learning theory: According to learning theory, children learn language in the same way that they learn other kinds of behaviour – through reinforcement. Parents reinforce children for making sounds that resemble adult speech, and so children make more of these sounds, generalizing and abstracting as they go along. Behaviourists believe that children utter sounds at random, and that those which sounds like adult speech are then reinforced. Social learning theorists maintain that children imitate the sounds they hear adults making and then are reinforced for doing so. Thus children in English speaking countries learn English rather than any other language. Imitation may explain why children generally outgrow incorrect usages even when their parents do not correct their grammar. Learning theorists point to the fact that children at home, who presumably hear more adult speech and get more attention and more reinforcement than those who grow up in institutions, do babble more. Limitation of learning theory: Learning theory does not account for children’s marvellously imaginative ways of saying things that they have never heard, like one girl’s description of walking on her heels as ‘tip-heeling’. Nativism: According to nativism, human beings have an inborn capacity for acquiring language and learn to talk as naturally as they learn to walk. Evidence for this viewpoint comes from several facts: Almost all children learn their native language, no matter how complex, mastering the basics in the same age-related sequence without formal teaching. Human beings, the only animals that have a spoken language, are also the only species in which the brain is larger on one side that the other, and seems to have an inborn mechanism for language localized in the larger hemisphere(for most people, the left hemisphere). Newborns respond to language in sophisticated ways. o They move their bodies in the rhythm of adult speech they hear, o They can tell their mother’s voices from those of strangers, o In the first month of life; they can distinguish very similar sounds. One researcher suggests that neonates can put sounds into categories because all human beings are ‘born with perceptual mechanisms that are tuned to the properties of speech,. Contact with the sounds of a particular language leads children to ‘tune in’ the corresponding present ‘channels’ and ‘tune out’ unused channels. These perceptual mechanisms, along with the vocal cords and the specialized speech centers of the brain, let a child ‘join the community of language’ quickly. How, after starting with simple recognition of sounds, do babies create complex utterances that follow the specific rules of language in their society? Noam Chomsky (1972) proposes one answer to this question: that an inborn language acquisition device (LAD) programs children’s brains to analyse the language they hear and to extract from it the rules of grammar. Using these rules, children can then make up original sentences. Deaf children make up their own sign language when they do not have models to follow – and this is more evidence that internal mechanisms play a large role in a young child’s growing linguistic capacity. Limitations of the Nativism theory: This approach does not explain why children differ so much in grammatical skill and fluency. The theory does not explain how they come to understand the meaning of words. Theory does not explain why speech development depends on having someone to talk with. Most developmentalists today draw on both nativism and learning theory; they believe that children enter the world with an inborn capacity to acquire a language, which is then activated and enhanced by learning through experience. Stages in Language Development: The following table lists language milestones during the first 3 years of life. Language Milestones from Birth to 3 Years Age Development Birth Babies can perceive speech, cry, make some response to sound 1 ½ to 3 months Coos and laughs 3 months Plays with speech sounds 5 to 6 months Makes constant sounds, trying to match what she or he hears 6 to 10 months Babbles in strings of consonants and vowels 9 months Begins to understand words (usually ‘no’ and baby’s own name), imitates sounds 10 months Loses ability to discriminate sounds not in own language 10 to 14 months Says first words (usually a label for something), imitates sounds 13 months Understands symbolic function of naming 14 months Uses symbolic gesturing 16 to 24 months Learns many new words, expanding vocabulary rapidly, going from about 50 words to up to 400; uses verbs and adjectives; speaks two word sentences 18 to 24 months Says first sentence 20 months Uses fewer gestures; names more things 24 months Uses many two-word phrases; no longer babbles; wants to talk. 30 months Learns new words almost every day; speaks in combination of 3 or more words; understands very well; makes many grammatical mistakes. 36 months Says up to 1000 words, 80% intelligible; makes few mistakes in syntax; grammar is close to informal adult speech. Prespeech: The word infant is based on the Latin word for ‘without speech’. Before an infant learns to say his or her first word like ‘dada’ or ‘hi’, all normal infants, make a variety of sounds from crying to cooing and babbling, accidental imitation, and then deliberate imitation. These sounds are known as pre-linguistic speech. Babies can distinguish between sounds long before they can utter anything but a cry. In the first few months of life, they can tell apart similar sounds like ‘bah’ and ‘pah’. This ability to differentiate sounds seems to be an inborn capacity that people lose as they hear the language spoken around them. Babies seem to lose this ability at about 9 or 10 months of age, when they begin to understand meaningful speech, but before they are physically mature enough to produce their own. Crying is the newborn’s first and only means of communication. To a stranger, a baby’s cries may sound alike, but the baby’s parents can often tell, for example, the cry for food from the cry of pain. Different pitches, patterns, and intensities signal hunger, sleepiness, or anger. At anywhere from 6 weeks to 3 months of age, babies start to laugh and coo when they are happy, making squeals, gurgles, and vowels like ‘ah’. A kind of ‘vocal tennis’ begins at 3 months, when they begin to play with speech sounds, producing a variety of sounds that seem to match the ones they hear from the people around them. Cross-cultural studies – on French, Chinese and Arabic speaking families – found that babies do not, as was once believed, ‘try out’ all speech sounds in all human languages, but instead move in the direction of their own language. Babbling – repeating consonant-vowel strings like ma-ma-ma-ma – occurs rather suddenly between 6 and 10 months of age, and these strings are often mistaken for the baby’s first words. Early babbling is not real language, since it does not seem to have meaning for the baby. But it becomes more word-like, leading into early speech. In this stage one kind of difference shows up between babies: o Word babies seem to understand words earlier and produce word sounds in their babbling. o Intonation babies babble in sentence like patterns and tend not to break their babbling strings down into individual words. At first babies accidentally imitate sounds they hear. Then they imitate themselves making these sounds. At about 9 to 10 months of age they deliberately imitate other sounds, without understanding them. Once they have this basic repertoire of sounds, they string them together in patterns that sound like language, but seem to have no meaning. This prelinguistic speech can be rich in emotional expression. Starting at about 2 months, when infants’ cooing begins to express contentment, the range of emotional tone increases steadily. Long before children can express any ideas in words, parents become attuned to their babies’ feelings through the sounds they make. Babies understand many words before they can say them. The first words most babies understand are either their own names or the word ‘no’ – which is not surprising,  considering the fact that these are the two words an active baby is likely to hear most often. They also pick up other words with special meaning for them, and parents sometimes have to start spelling words in front of 14 month olds if it is not time yet to give them their b-a-n-a-n-a. Throughout the prespeech period, parents and other caregivers have been actively communicating with a baby in many different ways. By the end of the first year the baby has: Some sense of intentional communication A primitive idea of reference And a set of signals that serve to communicate with the baby’s familiar caregivers. The linguistic stage is now set for speech. First words: The average baby says his or her first word sometime between 10 and 14 months, initiating linguistic speech – the use of spoken language to convey meaning. Before long, the baby will use many words and will also show some understanding of grammar, pronunciation, intonation, and rhythm. At this point, though, the sum total of infant’s repertoire is likely to be ‘mama’ or ‘dada’. Or it may be a simple syllable that has more than one meaning, depending on what is on the baby’s mind at the moment. For example, ‘da’ may mean ‘I want that’, ‘I want to go out’, and ‘Where is daddy?’ and so forth. A word like this is called a holophrase, because it expresses a complete thought in a single word. Growth of vocabulary: Typically, by 15 months of age a child of either sex has spoken 10 different words or names. Vocabulary continues to grow throughout the single-word stage (which tends to last until the age of about 18). There is also an increasing reliance on words. More and more occasions inspire the child to speak a word or a name. The sounds and rhythms of speech grow more elaborate, and even if much of the child’s speech is still babbling, it does seem quite expressive. In studying the first 50 words by a group of 1 and 2 year olds, Nelson found that the most common were names of things, either in the general sense (‘oof-oof’ for dog) or the specific (‘unga’ for one particular dog). Others were action words (‘bye-bye’), modifiers (‘hot’), words that express feelings or relationships (the ever popular ‘no’), and a few grammatical words (‘for’). By 13 months most children seem to understand the symbolic function of naming; that is, they realize that words stand for a specific thing or event. They add words slowly to their vocabulary until a ‘naming explosion’ occurs somewhere between 16 and 24 months, and the baby goes from saying about 50 words to saying about 400 within a few weeks. Symbolic Gesturing: Just before or at about the same time that babies say their first words, they often develop a repertoire of nonverbal gestures. ‘Symbolic gestures’ go beyond pointing and games like ‘pat-a-cake’, to represent specific objects, wants, desires, and conditions. Not all children use such gestures. Those who do typically start to use them at about 14 months to make requests, at about 15 months to describe attributes (like blowing to mean ‘hot’), and about 2 weeks later to ‘name’ objects. Symbolic gestures usually appear before children have a vocabulary of 25 words and drop out when the children learn the words for the ideas they were expressing in gestures. More than half the children developed gestures as a result of routines with their parents. (For example, ‘horsie’ gesture’). It takes two to communicate, and if parents do not interpret and respond to the gestures, children are likely to drop them and try to get adults’ attention in other ways – like grabbing or making sounds. These gestures show that even before children can talk, they understand that objects and concepts have names and that they can use symbols to refer to the things and happenings in their everyday life. Language and cognition in the first-word stage During the one-word period, cognitive and linguistic achievements seem very closely related. Within a few weeks of learning complex object permanence tasks, babies tend to acquire words for disappearance (like ‘gone’); and after they learn how to solve problems (using a stick to obtain an object, or putting necklace into a bottle), they often use words associated with success or failure (like ‘there’, ‘did it’). Babies are motivated to learn words that are important to them at the time. First sentences At 18 months, children generally speak two words to express one idea. This age at which children begin combining words varies, although the range is similar for children who learn spoken language and children of deaf parents who learn sign language. Generally they put words together between 18 and 24 months of age, about 8 to 12 months after the first word, but this is very variable. Although prelinguistic speech is fairly closely tied to chronological age, linguistic speech is not. Children’s first sentences generally deal with everyday events, things, people or activities. This early speech described as ‘telegraphic’, was once thought to be universal, but now we know that children vary individually in the extent to which they use telegraphic speech and that the form itself varies depending on the language being learned. Early syntax Children’s speech becomes increasingly complex. First, tense and case endings, articles, and prepositions are missing (‘shoe fall’); and frequently, so are subjects or verbs (‘mommy sock’). Next the child may string two basic relationships together (‘Adam hit’ and ‘hit ball’) to get a more complicated relationship (‘Adam hit ball’). Sometime between the ages of 20 and 30 months, children acquire the fundamentals of syntax. They begin to use articles (a, the), prepositions (in, on), plurals, verb endings, and forms of the verb ‘to be’ (am, are, is). By 3 years of age, their speech becomes longer and more complex; although they omit many parts of speech, they get their meaning across, and they are fluent speakers. Characteristics of Early Speech Children’s speech is not just an immature version of adult speech, it has a character all of its own. These are some of the characteristics of early speech: Children simplify: They say just enough to get their message across. ‘No drink milk’. Children overregularize rules: They apply the rules of grammar rigidly without knowing that some rules have exceptions. Having learned grammatical rules for plurals and past tense, they say ‘mouses’ and ‘goed’ instead of ‘mice’ and ‘went’. Children understand grammatical relationships that they cannot yet express: A child may understand that a dog is chasing a cat, but cannot string together enough words to express the complete action. The sentence comes out as ‘Puppy chase’ rather than ‘Puppy chase kitty’. Most children do something called ‘overgeneralizing concepts’ in early speech. For example, a child may call all four-legged animals ‘woof-woof’, and all grey haired men ‘grandpa’. Children underextend word meanings: Children tend to restrict the meaning of words. For example a child may call the toy car her father gave her as ‘kooka’, but may not accept that her friend’s car is also a ‘kooka’. Influences on language acquisition: What determines how quickly and how well a baby learns to speak? Again we see nature and nurture. Heredity: A genetic influence is apparent in the moderate relationship between parents’ intelligence and the rate at which their biological children develop communication skills during the first year of life. Such a relationship has been found for adopted children and their biological parents but not their adoptive parents. It also seems likely, however, that environmental factors, like parents’ imitation of the sounds infants make, also affect the pace of linguistic learning. Environment: Other research attributes many, if not most, of the marked differences in language abilities that surface by the end of a child’s second year to differences in children’s surroundings. One important environmental influence, of course, is how much and what kind of speech babies hear. A study in Bermuda found that 2 year olds in day care centers where caregivers speak to them often (especially to give or ask for information rather than to control their behaviour) are more advanced in language development than children who do not have such conversations with adults. Conversely, when children with normal hearing grow up in homes with deaf parents who communicate only through sign language, the children’s speech development is slowed. In order to speak and communicate, children need practice and interaction. Hearing speech on television is not enough; for example, Dutch children who watch German television everyday do not learn German. Language is a social act. By talking to babies parents and other caregivers teach them to use new words, structure phrases etc. They give children a basic sense of how to carry on a conversation – how to introduce a topic, comment and add on it, and take turns talking. Unquestionably, conversation with babies is important. The question is ‘what sort of conversation?’ Too much direction – commands, requests and instructions – is not helpful. Amongst the most helpful things adults can do is to: Paraphrase what the child says, Expand on it, Talk about what interest the child, Remain quiet too long to give the child a chance to respond, And use reading-aloud sessions Delayed Language Development: Albert Einstein did not start to speak until he was 3 years old, a fact that heartens the parents of other children, whose speech develops later than usual about 40% o late-talkers have other problems like hearing impairment or mental retardation. But there are many children with delayed language skills whose sensory, motor, cognitive and emotional abilities are on a par with or above those of their peers. It is still unclear why these children speak later than others. They are not necessarily from homes where they do not get enough linguistic input. Even though some of their parents may be talking to them, more in terms of what the children can say rather than in terms of what they can understand, this may be more the result than the cause of the delay. Current investigations focus on problems in information-processing, or ‘fast mapping’ new words, that is, absorbing the meaning of a new word on the basis of having heard it in conversation. In any case, these children can often benefit from special teaching programs at home, at pre- school and from a qualified professional.