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Cognitive Development in Infancy and Toddlerhood Chapter 5 Piaget’s Cognitive-Developmental Theory Children move through 4 stages of cognitive development between infancy and adolescence 1st stage – sensorimotor stage: birth-2 years Initially “think” with their eyes, ears, and hands By the end, children can solve problems and represent their experiences in speech and gesture Piaget’s Theory: Schemes Psychological structures Organized ways of making sense of experience Change with age 1st – schemes are action-based sensorimotor patterns Ex: a 6 month old drops objects in a rigid way, letting go of a rattle or teething ring and watching with interest Later move to “thinking before acting” pattern – creative and deliberate Ex. 18 month old, “dropping scheme” becomes more deliberate and creative, tossing toys down stairs, throwing them in the air, bouncing them off walls Building Schemes 2 processes account for changes in schemes, adaptation and organization Adaptation – involves building schemes through direct interaction with the environment Assimilation – use current schemes to interpret the external world Ex. When dropping objects, baby is assimilating them to his sensorimotor “dropping scheme” Accommodation – create new schemes or adjust old ones after noticing that the current ways of thinking do not capture the environment completely Ex. When a baby drops objects in different ways, it modifies its dropping scheme to take account of the varied properties of objects Linking Schemes Organization –new schemes are rearranged and linked with other schemes to create an interconnected cognitive system Internal process, apart from direct contact with the environment Ex. Baby will eventually relate “dropping” to “throwing” and to its developing understanding of “nearness” and “farness” The Sensorimotor Stage Circular reaction – stumbling onto a new experience caused by the baby’s own motor activity, then trying to repeat the event again and again A sensorimotor response that first occurred by chance becomes strengthened into a new scheme Provides basis for forming 1st schemes Ex. 2 month old accidentally makes a smacking noise after a feeding, then tries to repeat the noise until it is a little expert at lip smacking Initially centers on the infant’s own body Then turns toward manipulation of objects In the second year is aimed at producing novel outcomes Sensorimotor Substages Reflexive Schemes Birth –1 mo. Newborn reflexes Primary Circular Reactions 1–4 months Simple motor habits centered around own body Secondary Circular Reactions 4–8 months Repeat interesting effects in surroundings Coordination of Secondary Circular Reactions 8–12 months Intentional, goal-directed behavior; object permanence Tertiary Circular Reactions 12–18 months Explore properties of objects through novel actions Mental Representations 12 months – 2 years Internal depictions of objects or events; deferred imitation Sensorimotor Substages 1 – Reflexive schemes Babies suck, grasp, and look in much the same way no matter what experiences they encounter Ex. 2 week old laying in bed next to her father, begins sucking on his arm 2 – Primary circular reactions Repeat chance behaviors largely motivated by basic needs Ex. 1 month old will open its mouth differently for a nipple than for a spoon 3 – Secondary circular reactions Try to repeat interesting events in the surrounding environment that are caused by their own actions Ex. 4 month old accidentally knocks a toy hanging in front of her producing a fascinating swinging motion and attempts to repeat this effect Sensorimotor Substages 4 – Coordination of secondary circular reactions Combine schemes into new, more complex action sequences Intentional or goal directed behavior – coordinating schemes deliberately to solve simple problems Object permanence – understanding that objects continue to exist when out of sight Ex. Mother shows 11 month old a toy, then hides it under a blanket Infant coordinates two schemes, “pushing” the blanket aside and “grasping” the toy Still make the A-not-B search error If they reach several times for an object in 1st hiding place (A), then see it moved to a 2nd hiding place (B), they still search for it in the first hiding place (A) Sensorimotor Substages 5 – Teritary circular reactions Toddlers repeat behaviors with variation or experiment Ex. 16 month old figures out how to fit a shape through a hole in a container by turning and twisting it until it falls through Ex. 18 month old figures out how to use a stick to get toys that are out of reach Sensorimotor Substages 6 – Mental representations Ability to create internal depictions of information that the mind can manipulate Images – mental pictures of objects, people, and spaces Concepts – categories in which similar objects or events are grouped together Arrive at solutions suddenly rather than through trial-and-error, like they are experimenting with actions inside their heads Ex. 19 month old bumps his new push toy against a wall, pauses for a moment as if “thinking,” then immediately turns the toy in a new direction Deferred imitation – ability to remember and copy the behavior of models who are not present Make-believe play – acting out everyday and imaginary activities Follow-Up Research Many studies show that infants display certain understandings earlier than Piaget believed Ex. Even newborns try to explore and control the external world Violation-of-expectation method Used to explore what infants know about hidden objects and other aspects of physical reality Can habituate babies to a physical event (expose them to the event until their looking declines) Familiarize them with a situation in which their knowledge will be tested Can also show babies an expected event (one that follows physical laws) and an unexpected event (a variation of the first event that violates physical laws) Heightened attention to the unexpected event suggests that the infant is “surprised” by a deviation from physical reality and therefore, is aware of that aspect of the physical world Object Permanence Infants young as 2.5 to 3.5 months old show indications of object permanence, Piaget believed this didn’t occur until 8-12 months look longer at the unexpected event Suggests that they had some awareness that an object moved behind the screen would continue to exist Object Permanence Investigators measuring ERP brain-wave activity of 6 month olds found brain-wave patterns the same as those of adults told to sustain a mental image of an object Deferred Imitation Piaget: said doesn’t occur until 18 months Newer research 6 weeks old – facial imitation Infants who watched an unfamiliar adult’s facial expression imitated it when exposed to the same adult making a neutral expression the next day 6-9 months – copy actions with objects Infants who watched an adult perform specific actions with a puppet, reenacted those actions a day later when given the puppet 12-14 months – imitate rationally Infer others’ intentions More likely to imitate purposeful behaviors than accidental behaviors 18 months – imitate intended but not completed actions Ex. 18 month old watches mother try to pour cereal into a bowl but she misses and spills some on the counter, the child then starts picking up the cereal and dropping it into the bowl, indicating he knew what her intentions were Problem Solving Develop intentional action sequences around 7-8 months Piaget was right! BUT… representational skills soon permit more effective problem solving than Piaget’s theory suggests 10-12 months – solve problems by analogy Can take a solution strategy from one problem and apply it to other relevant problems Ex. 11 month old uses a stick to knock down a toy that is out of reach. Later, she uses her toy rake to knock her juice bottle off the table. Evaluation of Sensorimotor Stage Develop when • Object search • A-not-B Piaget • Make-believe play suggested • Object permanence Develop earlier • Deferred imitation than Piaget • Categorization suggested • Problem solving by analogy Some suggest infants are born with core knowledge in several domains of thought Alternative Explanations Most researchers now believe infants have some built-in cognitive equipment for making sense of experience But there is intense disagreement over the extent of this initial understanding Some researchers believe babies’ cognitive starting point is limited to a set of biases for attending to certain information and general-purpose techniques for analyzing perceptual information Others support the core knowledge perspective Acknowledges that experience is essential for children to extend their initial knowledge but does not identify which experiences are most important Core Knowledge Perspective Babies are born with a set of innate knowledge systems, or core domains of thought, that support early, rapid development Argues that infants could not make sense of the complex stimulation around them without having been genetically “set up” to do so Acknowledges that experience is essential for children to extend their initial knowledge but does not identify which experiences are most important In the first few months of life infants already have some physical knowledge Awareness of basic object properties such as permanence, solidity, and gravity An inherited foundation of linguistic knowledge enables rapid language acquisition Infants’ early orientation toward people initiates rapid development of psychological knowledge Understanding of mental states, intentions, emotions, desires, and beliefs Information Processing Contrasts Piaget’s unified theory of cognitive development Focuses on various aspects of thinking, including attention, memory, categorization skills, and problem solving Remember the flow charts for problem solving? Structure of the Information-Processing System Assumes that we hold information in 3 parts of the mental system Sensory register, working or short-term memory, and long-term memory Assumes we use mental strategies to operate on information so that we will retain it, use it efficiently, and adapt it to changing circumstances Believe the basic structure of the system remains similar throughout life But, capacity (amount of information that can be retained and processed at once) and the speed of processing information increases, making more complex forms of thinking possible with age Structure of the Information-Processing System Sensory register – where information enters, sights and sounds are represented directly and stored briefly Working, or short-term memory – 2nd part of the mind, where we actively apply mental strategies as we “work” on a limited amount of information As we connect separate pieces of information into a single representation, we make more room in working memory for more information The central executive, a special part of working memory, is the conscious, reflective part of our mental system Decides what to attend to and coordinates incoming information with information already in the system Long-term memory – 3rd and largest storage area, our permanent knowledge base, unlimited The longer we hold information in working memory, the more likely it will be transferred to long-term memory Retrieval – getting information back from the system, aided by categorization (like a library arranged by subject) Attention Infants gradually attend to more aspects of the environment, taking in information more quickly Ex. Newborns require 3-4 minutes to habituate and recover to novel visual stimuli By 4-5 months old habituation to complex visual stimulus takes about 5- 10 seconds With the transition to toddlerhood, sustained attention improves Ability to keep attention focused Ex. A toddler who stacks blocks or puts them in a container must sustain attention long enough to reach the goal Memory Retention of visual events increases dramatically over infancy and toddlerhood 3 month olds – remember habituated action for 1 week 6 month olds - remember habituated action for 2 weeks Continues to increase with age Recognition – noticing when a stimulus is identical or similar to one previously experienced Simplest form of memory: all babies have to do is indicate that a new stimulus is identical or similar to a previous one Recall – more challenging because it involves remembering something not present Emerges by 12 months of age Indicated by ability to find hidden objects and imitate others’ actions long after observing the behavior Categorization Even young infants can categorize Grouping similar objects and events into a single representation Helps infants learn and remember new information Earliest categories are perceptual Based on appearance (shape, size, color, and other physical properties) By end of 1st year of life are conceptual Based on common functions (food items, furniture, animals, plants, vehicles, kitchen utensils and spatial location) In the 2nd year toddlers become active categorizers Play behaviors (such as touching and sorting) reveal the meaning they have attached to categories Ex. 14 month olds shown a rabbit and a motorcycle usually offer a drink only to the rabbit, indicating they understand that certain actions are appropriate for some categories but not for others Exploration of objects and expanding knowledge of the world, as well as advancing vocabulary, contribute to the capacity to group objects by functions and behaviors Evaluation of Information-Processing Findings Emphasized the continuity of human thinking from infancy into adulthood Challenging Piaget’s stage view of early cognitive development Ex. If 3 month olds can remember events over a period of time and can categorize stimuli, then they must have some ability to mentally represent their experiences Piaget believed mental representation did not occur until 18 months Major strength: analyzing cognition into its components Also its major weakness: hasn’t yet put these components together into a comprehensive theory How to overcome this weakness Combine Piaget’s theory with the information-processing approach Apply a dynamic systems view Analyze each cognitive attainment to see how it results from a complex system of prior accomplishments and the child’s current goals Social Context of Early Cognitive Development Vygotsky’s sociocultural theory: complex mental activities are based in social interaction Through joint activities with more mature members of their society, children master activities and think in ways that are meaningful in their specific culture Zone of proximal development – a range of tasks that a child cannot yet handle alone but can do with the help of more skilled partners Ex. Adult introduces child to a new activity the child is capable of mastering but is challenging enough that the child cannot do it alone As the adult guides and supports, the child joins in the interaction and picks up mental strategies As the child’s competence increases, the adult steps back, permitting the child to take more responsibility for the task Social Context of Early Cognitive Development Vygotsky’s idea have been applied mostly to older children, who are more skilled in language and social communication Recently, these ideas have been extended into infancy and toddlerhood Babies are equipped with capacities that ensure that caregivers will interact with them Then adults adjust the environment and their communication in ways that promote learning adapted to their cultural circumstances Vygotsky shows how cultural variations in social experiences affect the development of mental strategies Individual Differences in Early Mental Development Mental tests measure cognitive products that reflect mental development and predict future performance Contrasts cognitive theories which are concerned with the process of development Goal of mental tests: measure behaviors that reflect development and arrive at scores that predict future performance Such as later intelligence, school achievement, and adult vocational success Infant and Toddler Intelligence Tests Challenging because babies cannot answer questions or follow directions Simply present stimuli and observe the babies’ responses Most tests emphasize perceptual and motor responses Some new tests focus on early language, cognition, and social behavior Bayley Scales of Infant and Toddler Development Used with children from 1 month to 3.5 years old Most recent edition: Baley-III, 3 main subtests Cognitive scale Includes items regarding attention to familiar and unfamiliar objects, looking for a fallen object, and pretend play Language scale Assesses understanding and expression of language Ex. Recognition of objects and people, following simple directions, and naming objects and pictures Motor scale Includes gross and fine motor skills, such as grasping, sitting, stacking blocks, and climbing stairs 2 additional scales depend on parental report Social-emotional scale: asks caregivers about behaviors such as ease of calming, social responsiveness, and imitation in play Adaptive behavior scale: asks about adaptation to the demands of daily life, including communication, self-control, following rules, and getting along with others Computing Intelligence Test Scores Intelligence tests for infants, children, and adults are scored in much the same way Intelligence Quotient (IQ) – indicates the extent to which the raw score (# of items passed) deviates from the typical performance of same-aged individuals To make this comparison possible test designers engage in standardization Standardization – giving the test to a large, representative sample and using the results as the standard for interpreting scores Within the standardization sample, results at each age level form a normal distribution Normal distribution – a bell-shaped curve in which most scores fall near the mean, or average, with progressively fewer towards the extremes Computing Intelligence Test Scores When intelligence tests are standardized, the mean IQ is set at 100 An individual’s IQ is higher or lower than 100 by an amount that reflects how much his or her test performance deviates from the standardization-sample mean IQ offers a way of finding out whether an individual is ahead, behind, or on time in mental development compared with others of the same age Predicting Later Performance from Infant Tests Infant tests are poor predictors of later intelligence Infants and toddlers easily become distracted, fatigued, or bored during testing, so their scores often do not reflect their true abilities However, Bayley-III cognitive and language scales are good predictors of pre-school mental test performance Because items on infant tests do not tap the same dimensions of intelligence measured at older ages, they are labeled developmental quotients, or DQs (not to be confused with Dairy Queen) Infant test scores are somewhat better at making long-term predictions for extremely low-scoring babies Thus are largely used to help identify babies who are at-risk for developmental problems Early Environment and Mental Development Home environment Home Observation for Measurement of the Environment (HOME) – checklist for gathering information about the quality of children’s home lives through observation and parental interviews Regardless of SES and ethnicity an organized, simulating physical setting and parental affection, involvement, and encouragement of new skills repeatedly predict better language and IQ scores in toddlerhood and early childhood Especially the extent to which parents talk to infants and toddlers When parents interact intrusively, bombarding young children with instructions, infants and toddlers are likely to play immaturely and do poorly on mental tests Infant and Toddler Child Care Today, more than 60% of U.S. mothers with a child under age 2 are employed Quality of child care for infants and toddlers has an impact on development of cognitive and social skills regardless of SES or ethnicity Poor-quality child care: score lower on measures of cognitive and social skills Good child care: can reduce the negative impact of a stressed, poverty-stricken home life can sustain the benefits of growing up in an economically advantaged family Infant and Toddler Child care Many U.S children from low-income families have inadequate child care Worst child care: middle-SES families Especially likely to place children in for-profit centers where quality tends to be the lowest Low-SES children more often attend publicly subsidized, nonprofit centers, which have smaller group sizes and better child-teacher ratios Signs of Developmentally Appropriate Infant and Toddler Child Care Physical setting Environment is clean, in good repair, well-lit, and well-ventilated, not overcrowded Toys and equipment Appropriate for infants and toddlers, stored on low shelves within easy reach; cribs, high-chairs, infant seats, and child-sized tables and chairs are available Caregiver-child ratio No greater than one to three for infants and one to six for toddlers; staffing is consistent, so infants and toddlers can form relationships with particular caregivers Daily activities Times for active play, quiet play, naps, snacks, and meals; schedule is flexible rather than rigid Interactions among adults and children Caregivers respond promptly to infants’ and toddlers’ distress; hold, talk to, sing to, and read to them Caregiver qualifications Some training in child development, first aid, and safety Relationships with parents Parents welcome anytime; caregivers talk frequently with parents Licensing and accreditation Licensed by the state Early Intervention for At-Risk Infants and Toddlers Studies indicate that poverty-stricken children are likely to show gradual declines in intelligence test scores and to achieve poorly when they reach school age Due to stressful home environment that undermines children’s ability to learn and that increase their likelihood of remaining poor throughout their lives Center based – children attend an organized child-care or preschool program where they receive educational, nutritional, and health services, and parents receive child-rearing and other social-service supports Home based – skilled adult visits the home and works with parents, teaching them how to stimulate young children’s development Early Intervention for At-Risk Infants and Toddlers Children participating in interventions, both center and home based, score higher than untreated controls on mental tests by age 2 The earlier and longer the intervention, the better the cognitive and academic performance in childhood and adolescence In one research project, the treatment group of children who participated in year-round full time child care program showed greater academic achievements throughout the school years as well as higher rates of college enrollment Sad reality: without some form of early intervention, many children born into economically disadvantaged families will not reach their potential Language Development In the 1950s researchers did not take seriously the idea that very young children might be able to figure out important properties of language As a result the first two theories of language development were extreme views Behaviorism – regards language development as entirely due to environmental influences Nativism – assumes that children are “pre-wired” to master the intricate rules of their language Behaviorist Perspective B.F. Skinner proposed that language, like all behaviors, is acquired through operant conditioning When parents reinforce their baby’s sounds that most sound like words Ex. Baby babbles “book-a-book-a-dook-a-nook-a” While baby is babbling, parents show it a book and say “book” Soon after, baby will say “book-aaa” when it sees a book Imitation combines with reinforcement to promote language development But, both are viewed as supporting language rather than fully explaining it Nativist Perspective Linguist Noam Chomsky’s theory regards young childrens’ language skill as innate Children are born with a language acquisition device (LAD) containing a set of rules common to all languages Permits children to understand and speak whichever language they hear in a rule-oriented fashion, as soon as they learn enough words Nativist perspective is consistent with evidence that childhood is a sensitive period for language acquisition Challenges to Nativism suggest that it is not a complete account of language acquisition Children do not acquire language as quickly as nativist theory suggests They refine grammatical forms more gradually than Chomsky assumed For most people, language is housed largely in the left hemisphere of the cerebral cortex, but language areas in the cortex also develop as children acquire language Interactionist Perspective Emphasizes interactions between inner capacities and environmental influences Some interactionists apply information-processing theory to language development Believe that children use powerful general cognitive capacities to make sense of their complex language environment Other interactionists emphasize that children’s social skills and language experiences are centrally involved in language development An active child, well-endowed for making sense of language, strives to communicate In doing so, the child cues her caregivers to provide appropriate language experiences, which help relate the content and structure of language to its social meaning http://www.youtube.com/watch?v=KfOlPK2P_G8 Getting Ready to Talk Cooing and babbling Around 2 months – babies begin to make vowel-like noises (called cooing) Around 6 months – babbling appears: infants repeat consonant-vowel combinations in long strings Ex. “bababababa” or “nanananana” By around 7 months – babbling includes many sounds common in spoken languages By 10 months – babbling reflects the sound and intonation patterns of the infant’s language community Babies everywhere, even those who are deaf, start babbling at about the same age and produce a similar range of early sounds But for speech to develop further, infants must be able to hear human speech and if a deaf infant is not exposed to sign-language babbling will stop entirely Deaf infants exposed to sign-language from birth babble with their hands Getting Ready to Talk Becoming a communicator At birth, infants initiate interaction through eye contact and end it by looking away Preparation for some aspects of conversational behavior By 4 months – infants start to display joint attention: gazing in the same direction adults are looking in Joint attention becomes more accurate around 10-11 months Adults also follow the baby’s gaze and label what is seen Around 4-6 months – caregiver-infant interaction begins to include give-and-take, as in pat-a-cake and peek-a-boo games At the end of the 1st year infants use preverbal gestures to influence the behavior of others Parents responsiveness teaches them that using language leads to desired results Ex. Pointing at the refrigerator when hungry, mother then feeds the child First Words 2nd half of the 1st year – infants begin to understand word meanings Utter 1st words around 1 year This achievement builds on the sensorimotor foundations Piaget described and on categories that children form during the 1st 2 years Usually they refer to important people (“mama,” “dada”), animals (“doggie,” “kitty”), objects that move (“ball,” “car”), foods (“milk,” “apple”), familiar actions (“bye-bye,” “more”), or outcomes of familiar actions (“wet,” “hot”) In their 1st 50 words, toddlers rarely name things that just sit there, like “table” or “vase” First Words When toddlers first learn words, they often apply them too narrowly, an error called underextention Ex. 16 month old only uses the word “doggie” to refer to her stuffed dog As vocabulary expands, a more common error is overextention – applying a word to a wider collection of objects and events than is appropriate Ex. Using the word “car” for buses, trains, trucks, and fire engines Overextentions reflect toddlers’ sensitivity to categories, as in use of “car” for all wheeled objects Overextentions illustrate the distinction between language production (the words children use) and language comprehension (the words they understand) At all ages language comprehension develops before language production Ex. A 2 year old who refers to trucks, trains, and bikes as “car” may look at or point to these objects correctly when given their names The 2-Word Utterance Phase Young toddlers add 2 to 3 words per week to their spoken vocabularies But between 18 and 24 months, children may add 1 to 2 words per day Once toddlers can produce about 200 words, they begin to form 2-word utterances called telegraphic speech “go car,” “mommy shoe,” “door open” 2-word speech consists largely of simple formulas “more + X,” “eat + X” with different words inserted in the X position Toddlers rarely make gross grammatical errors Saying “chair my” instead of “my chair” Word-order regularities are usually copies of adult word-pairings ex. “would you like some more sandwich,” toddler will learn to repeat “more sandwich” Indicates toddlers first acquire “concrete pieces of language” from frequent word parings they hear and they gradually generalize from those pieces to construct word order and other grammatical rules Individual Differences On average, children produce 1st word around their 1st birthday But the range is large, from 8-18 months Studies show that girls are slightly ahead of boys in early vocabulary growth Personality is also a factor, with shy toddlers slightly behind their agemates Shy toddlers often wait until they understand a great deal before trying to speak, but once they do speak their vocabularies increase rapidly The more words caregivers use the more children learn 2 distinct styles of early language learning Referential style – vocabularies consist mainly of words that refer to objects (most common style) Expressive style – learn to produce many more pronouns and social formulas (“thank you”) Because they believe words are for talking about people’s feelings and needs Supporting Early Language Infants Respond to coos and babbles with speech sounds and words Encourages experimentation with sounds that can later be blended into first words Provides experience with turn-taking pattern of human conversation Establish joint attention and comment on what child sees Predicts earlier onset of language and faster vocabulary development Play social games, such as pat-a-cake and peekaboo Provides experience with turn-taking pattern of human conversation Supporting Early Language Toddlers Engage in joint make-believe play Promotes all aspects of conversational dialogue Engage in frequent conversations Predicts faster early language development and academic success during school years Read to child often, engaging them in dialogues about picture books Provides exposure to many aspects of language including vocabulary, grammar, communication skills, and information about written symbols and story structures Supporting Early Language Adults also unconsciously support early language learning through child-directed speech (CDS) CDS – form of communication made up of short sentences with high-pitched, exaggerated expression, clear pronunciation, distinct pauses between speech segments, and repetition of new words in a variety of contexts Fosters development of joint attention, turn-taking, and caregivers’ sensitivity to toddlers’ preverbal gestures Ex. Toddler: “go car” Mother: “Yes, time to go in the car. Where is your jacket?” Toddler: [looks around, walks to the closet.] “Dacket!” Mother: “There’s that jacket! [helps toddler the jacket] On it goes! Let’s zip up. [Zips up the jacket]
