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Infancy Cognitive Development Truth or Fiction

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					     Infancy:
Cognitive Development
Cognitive Development

      Jean Piaget
          Cognitive Development – Jean Piaget


• Focus on development of children’s ways of perceiving and
  mentally representing the world
• Schemes
   – Concepts
• Assimilation
   – “Fit” new ideas into existing schemes
• Accommodation
   – Modify schemes to accept new ideas
            What Is the Sensorimotor Stage
             of Cognitive Development?

• Birth through 2 years

• Development through
   – sensory and
   – motor activity

• Progress from reflex responses to goal-oriented behavior
   – Form mental representations
   – Hold complex pictures of past events in mind
   – Solve problems by mental trial and error
         Substages of the Sensorimotor Stage

• Simple Reflexes
   – Birth to 1 month
   – Modify reflexes based on experience
• Primary Circular Reactions
   – 1 to 4 months
   – Primary = focus on infant’s own body
   – Circular = repeated behaviors
• Secondary Circular Reactions
   – 4 to 8 months
   – Secondary = focus on objects or environmental
     events
   – Track moving objects until they disappear from view
         Substages of the Sensorimotor Stage


• Coordination of Secondary Schemes
   – 8 to 12 months
   – Coordinate schemes to attain specific goals
   – Begin to imitate others
• Tertiary Circular Reactions
   – 12 to 18 months
   – Deliberate trial and error behaviors
• Invention of New Means Through Mental Combinations
   – 18 to 24 months
   – External exploration is replaced by mental exploration
        How Does Object Permanence Develop?


• Neonates show no response to objects not within their
  immediate grasp
• 2 month - show surprise when a screen is lifted after an
  object was placed behind a screen and now is not there
   – Child makes no effort to search for the missing object
• 6 month - try to retrieve a preferred object partially
  hidden
• 8- to 12-month - try to retrieve objects completely hidden
• More recent research – object permanence in some form
  as early as 2½ - 3½ months
         Development of Object Permanence




Figure 6.1
   Object Permanence Before 4 Months of Age?




Figure 6.2
         What Are the Strengths/Weaknesses
                of Piaget’s Theory?

• Strengths:
   – Comprehensive model
   – Confirmation from research of others
   – Pattern and sequence appear cross-culturally
• Weaknesses:
   – Stages are more gradual than discontinuous
   – Underestimate infants’ competence
      • Emergence of object permanence
      • Deferred imitation
      • Computational concepts
Counting in the Crib?
Information Processing
 What Are Infants’ Tools for Processing Information?


• Memory
   – Neonates show memory for previously exposed
     stimuli
   – By 12 months dramatic improvement in encoding and
     retrieval
• Rovee-Collier (1993) studies of infant memory
   – Given a reminder (priming), improves memory
Investigating Infant Memory
 What Are Infants’ Tools for Processing Information?


• Imitation
   – Deferred imitation – as early as 6 months
   – Neonates imitate adults who stick out their tongue
      • Not present in older infants – likely reflexive
   – Speculation on newborn’s ability to imitate
      • Aids in caregiver – infant bonding
      • Mirror neurons
             Imitation in Infants




Figure 6.5
Social Influences on Early
 Cognitive Development
         Lev Vygotsky’s Sociocultural Theory


• Sociocultural theory – emphasis on teaching and
  learning
• Zone of proximal development
   – Examples: Adult naming things; reading a picture
     book
• Scaffolding
   – Higher maternal scaffolding – better results on
     second “child-only” task
             How Well Do Infant Scales Predict
              Later Intellectual Performance?

• Overall infant scale scores do not predict school grades or IQ of
  schoolchildren
• Visual recognition memory – ability to discriminate previously
  seen objects from novel objects
   – Good predictive validity for IQ and language ability
• Infant intelligence tests best as screening and research
  instruments
Language Development
         What Are Prelinguistic Vocalizations?


• Prelinguistic vocalizations do not represent objects or
  events
• Examples of prelinguistic vocalizations
   – Crying
   – Cooing – vowel-like, linked to pleasant feelings
   – Babbling – combine vowels and consonants
   – Intonation – patterns of rising and falling melody
            How Does Vocabulary Develop?


• Receptive vocabulary outpaces expressive
• First word – typically 11 to 13 months
   – 3 or 4 months later – 10 to 30 words
• First words general nominal and specific nominal
   – General (class nouns) and specific (proper nouns)
   – Movement words represented in early speech
• 18 to 22 months - rapid increase from 50 to more than
  300 words
          How Do Infants Create Sentences?


• Holophrases
   – Single words used to express complex meanings
• Two word sentences – Telegraphic Speech
   – 18 to 24 months telegraphic two word sentences
     begin
   – Demonstrate syntax
Theories of Language
   Development
               Environmental Theories -
                  Learning Theories

• Imitation
   – Children learn from parental models
   – Does not explain uttered phrases that have not been
     observed
• Reinforcement
   – Sounds of adults’ language are reinforced
   – Foreign sounds become extinct
   – Use of shaping
   – Parents do not exclusively reinforce correct syntax
                    Environmental Theories -
                     Infant-Directed Speech

• Infant-directed speech – Motherese
   –   Spoken more slowly, briefer sentences
   –   Simple syntax
   –   Key words are at end and spoken in higher pitch
   –   Add diminutive morpheme y to nouns
   –   Repeated sentences, reduplication
   –   Focus on naming and describing objects
                     Biological Theories -
                         Nativist View

• Innate factors cause children to attend to and acquire language
  in certain ways

• Psycholinguistic Theory
   – Interaction between environmental influences and inborn tendency
     to acquire language
                Language Acquisition Device


• The inborn “prewired” tendency to acquire a language

• Evidence for LAD – Language Acquisition Devise (Chomsky)
   – Universality of language abilities
   – Regularity of early production of sounds, even among deaf children
   – Invariant sequences of language development, regardless of
     language


• Inborn tendency primes nervous system to learn grammar
                   Biological Theories -
                     Sensitive Period
                in Language Development

• Plasticity of brain provides a sensitive period of learning
  language
   – Begins about 18 to 24 months and continues through
     puberty
• Left hemisphere injuries
   – Children recover good deal of speech, utilizing right
     hemisphere
   – Case studies
       • Genie
       • Simon and ASL
           What Parts of the Brain Are Involved
              in Language Development?

• Key structures for most people are based in left hemisphere
   – Broca’s area
   – Wernicke’s area
• Aphasia – caused by damage in either area
   – Broca’s aphasia – slow laborious speech with simple sentences
   – Wernicke’s aphasia – impairment comprehending speech of others
     and expressing their own thoughts
• Angular gyrus
   – Translates visual information into auditory sounds
   – Impairment can cause reading difficulties and dyslexia
Broca’s and Wernicke’s Areas of the Cerebral Cortex




 Figure 6.7