Development

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Development
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Three Minute Review

• NONVERBAL COMMUNICATION
• eye contact
• body language
• gestures
• why do people gesture on the phone?
• interactional synchrony
• deception
• LANGUAGE DEVELOPMENT
• Skinner vs. Chomsky
• operant conditioning vs. language instinct
• childrens overgeneralization
• grammatical errors and Wug test

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• LANGUAGE DEVELOPMENT
• critical periods
• 6 months for learning phonemes
• 6 years for learning grammar
• language learning in animals
• lower larynx enables human speech
• apes have to use ASL or symbolic language
• debate about whether its really language

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Test Yourself

• A child who uses the word wawa to refer not
  only to water but to milk, juice and other drinks
  is
• overextending the word
• underextending the word
• demonstrating conditioning of the word wawa
  with any liquid
• babbling
• autistic

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Development

• Physical Development
• Cognitive Development
• Social Development

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Brain Development
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Brain Development

• during pregnancy, the brain can be highly
  susceptible to teratogens
• radiation, drugs, viruses, toxins
• explanation for morning sickness?
• fetal alcohol syndrome
• cluster of defects occurring in infants born to
  mothers that drink heavily during pregnancy
• leading cause of mental retardation
• even moderate drinking (e.g., three beers a day)
  may lead to children with a lower IQ and shorter
  attention span

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Neural Development

• Grow, then prune
• Neural Darwinism
• make too many neurons, then prune the ones youre
  not using
• use it or lose it
• there are 30-60 more neurons in the fetus than
  in the adult brain

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Myelinization

• basic sensory and motor areas become myelinated
  early
• association areas become myelinated later

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Cognitive Development

• The infants world is a blooming, buzzing
  confusion
• -- William James
• How can you study perception and cognition in a
  non-verbal being (preverbal child, animal)?
• Visual tracking
• Preferential looking
• Eye movement monitoring
• Habituation
• Sucking

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Visual Tracking

• newborns will track facelike stimuli
• innate preference for faces?

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Orienting and Habituation

• Orienting reflex
• humans, including infants, pay more attention to
  novel than familiar stimuli
• Habituation
• infants get bored with repeated presentations of
  the same thing
• Habituation paradigm
• repeat the same stimulus over and over again,
  then change it slightly
• does infant spend more time looking at new
  stimulus?

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Preferential Looking

• present two stimuli on either side of centre
• watch where infants look
• in the best studies, the mom and experimenter are
  blind to the stimuli
• spontaneous looking preferences
• e.g., infants prefer high contrast
• habituation
• familiarize infant with one stimulus, then
  present it in combination with a new stimulus
• infant looks more at new stimulus ? infant could
  tell the difference
• infant looks equally at old and new stimuli ?
  infant couldnt tell the difference

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What have we learned?

• Although newborns can see faces, faces must
  appear very blurry to them

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Eye Movements

• newborns look at outside features of faces
• older infants, like adults, spend much time
  looking at eyes and mouth

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Behavior

• Visual Cliff
• Will the baby crawl over the glass to get to mom?
• mobile infants wont
• pre-mobile infants did not appear bothered when
  placed on the glass

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Sucking Response

• newborns suck more when they hear their native
  language
• newborns suck more when they hear their moms
  voice

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Critical Periods
(See Gray, pp. 135)
Konrad Lorenz 1903-1989

• Imprinting
• baby ducks and goslings will follow on the first
  individual they encounter, even if its a human
  rather than the mother
• imprinting must happen within five days after
  hatching

Critical period A period in development during
which some event has a long-lasting influence on
the brain and behavior that it would not have if
it occurred outside that period
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Does Development Occur Continuously or in Stages?
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Jean Piaget

• Piaget, a Swiss psychologist, believed that
  children are active thinkers, constantly trying
  to construct more advanced understandings of the
  world
• These understandings are in the form of
  structures he called schemes

Jean Piaget 1896-1980
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Assimilation and Accomodation

• Schemes are frameworks that develop to help
  organize knowledge
• Assimilation - process of taking new information
  or a new experience and fitting it into an
  already existing scheme
• Accommodation - process by which existing schemes
  are changed or new schemes are created in order
  to fit new information

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Piagets Approach

• Primary method was to ask children to solve
  problems and to question them about the reasoning
  behind their solutions
• Discovered that children think in radically
  different ways than adults
• Proposed that development occurs as a series of
  stages differing in how the world is understood

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Sensorimotor Stagebirth - 2 years

• Information is gained through the senses and
  motor actions (looking, touching, mouthing)
• In this stage child perceives and manipulates but
  does not reason
• Infant gradually becomes aware of relationship
  between own actions and their effects on
  environment
• Object permanence is acquired

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Sensorimotor Development
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Object Permanence

• 8 - 10 mos. Infant begins to understand that
  objects exist even when not in view

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Preoperational Stage2 - 7 years

• Represents things with words and images but lacks
  logical reasoning
• Can think symbolically (e.g., pretending a stick
  is a gun)
• Thinking is egocentric has difficulty taking the
  viewpoint of others
• Fails to understand conservation

What does the doll see?
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Conservation of Number
Is there the same number in each row?
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Conservation of Length
Which stick is longer?
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Conservation of Volume
Which container has the most volume
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Conservation of Mass
Which is bigger?
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Concrete Operational Stage7-12 years

• Can think logically about objects and events
• Can see others perspective
• Achieves conservation of number (age 6), mass
  (age 7) and weight (age 9)

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Formal Operational Stage11 years and up

• Can think logically about abstract propositions
  and test hypotheses systematically
• Can understand hypothetical propositions
• e.g., If all animals can fly and if rhinoceroses
  are animals, then all rhinoceroses can fly.
• Becomes concerned with the the future and
  ideological problems
• Not achieved by all adults

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Critiques of Piagetian Theory

• Underestimates childrens abilities
• Overestimates age differences in thinking
• Vagueness about the process of change
• Underestimates the role of the social environment
• tests were done on Western European kids
• Vygotsky argued culture and social interaction
  were critical to development
• Lack of evidence for qualitatively different
  stages
• Not well integrated with neuroscience

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Contradictory Experiments

• In preferential looking experiments, 4 month old
  infants who did not demonstrate object permanence
  nonetheless looked longer at an unexpected
  occlusion event

• Preoperational children chose the column with
  more MMs

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Information Processing Perspective

• Focuses on the mind as a system, analogous to a
  computer, for analyzing information from the
  environment
• Developmental improvements reflect
• increased capacity of working memory
• faster speed of processing
• new algorithms (methods)
• more stored knowledge