Final Exam

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Final Exam

• Thursday
• April 15
• 830-1130
• CSE - B

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Language Development

• Language seems to be a uniquely human ability,
  suggesting an evolutionary foundation
• Arguments against a purely genetic explanation
• Productivity of novel phrases and statements
• Variety of languages and grammatical structures

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Language Development
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Auditory Processes

• Like with vision and contrast sensitivity
• Newborns hear sounds better at low frequencies
• By 6 months, higher frequency sensitivity is as
  good as adults
• Overall sensitivity increases until 10 years, but
  higher frequency sensitivity does not improve
  after 4 or 5 years

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Auditory Processes

• In fact, around 6 months can discriminate tones
  that differ only by 2 in frequency
• Even more complex sounds than simple tones, young
  infants can discriminate
• 6 months discriminate changes in the rhythm and
  melody of music and they can match melodies even
  if the key (pitch) changes
• Means that they can perceive the relations among
  the frequencies
• And they can tell the difference between a
  lullaby and an adult-directed song

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Auditory Localization

• This is important for eventually matching sounds
  to people and objects
• Even newborns will turn their heads to the left
  or right toward the source of a sound
• Human voices are particularly effective
• Requires detection of the time difference between
  sound reaching the two ears
• This a particular problem in development because
  head is constantly growing

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Preverbal Infancy

• Language acquisition works through the perception
  of speech and its sounds
• Must learn to parse the stream of sound into
  phonemes, syllables, words, and phrases.
• Phoneme - is the smallest unit of sound that when
  changed, changes meaning

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Categorical Perception

• Infants can discriminate when two sounds are the
  same or different phonemic category
• Phonemes are distinguished by their voice-onset
  time between lip opening and voicing by vocal
  cords

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Categorical Perception

• Eimas, Siqueland, Jusczyk Vigorito (1971) - 1-
  and 4-mo-olds perception of the distinction
  between /b/ and /p/
• Adults - VOT of less than 25 msec, perceive /b/

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Categorical Perception

• Eimas, Siqueland, Jusczyk Vigorito (1971) -
  familiarized infants to 20 msec VOT (/b/) and
  tested them with either 40 msec (/p/), 20, or 0
  (/b/)

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Categorical Perception

• Eimas, Siqueland, Jusczyk Vigorito (1971) -
  familiarized infants to 20 msec VOT (/b/) and
  tested them with either 40 msec (/p/), 20, or 0
  (/b/)

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Categorical Perception

• Eimas, Siqueland, Jusczyk Vigorito (1971) -
  familiarized infants to 20 msec VOT (/b/) and
  tested them with either 40 msec (/p/), 20, or 0
  (/b/)

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Phonemic Discrimination

• In the Japanese language, adults have trouble
  pronouncing and even discriminating between /r/
  and /l/
• They are not used in their language
• Young Japanese infants can discriminate between
  these sounds
• At some point they lose this ability (6-12 mos.)
• Indicates that if you do not use it or have
  exposure to it, you lose it

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Discriminating 2 Hindi syllables
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Universal Phonetic Sensitivity
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Early Baby Sounds

• 2 months - Cooing
• One syllable sounds, like ah and oo
• Associated with positive emotions
• 6 months - Reduplicated Babbling
• Strings several instances of same sound together,
  like bababa
• This babbling is similar across different
  cultures and languages

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Early Baby Sounds

• End of First Year
• Stop duplicating and begin to string different
  sounds together
• Include changing intonation and pitch
• These sounds and strings are very similar to
  their first words
• Even deaf infants display babbling
• Suggesting a biological mechanism
• But, they are delayed in duplicating and
  production of proper syllables

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Nonverbal Language

• Gestures first seem to be use around 8-10 months
• Used to indicate requests, for example, wanting a
  toy
• Might be related to physical development
• Around 11-12 months, gesture start to be used for
  referential communication
• To indicate items or events in environment
• Example, holding up a toy to show it

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Nonverbal Language

• Gestures are used to symbolize objects
• For example, talking on a phone
• Used to indicate attributes of object or events
• For example, this is big
• End of first year, get combination of gestures
  and vocalizations
• Then, gestures start to fall out and get
  transition to their first words.

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First Words

• Sounds and sound combinations get attached to
  particular objects with greater frequency
• These sounds do not correspond to words we use
• These sounds get shaped gradually and
  continuously to correspond more closely to our
  words

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First Words

• When they first appear shows considerable
  variability, from 9 months to 16 months
• First words are typically of items that are
  familiar and important in their day-to-day lives
• They appear to occur in particular contexts
• Bates (1979) and Barrett et al. (1986)
• no when rejecting an object
• bye when putting down a telephone
• papa when the doorbell rings

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First Words

• Eventually, these first words become
  decontextualized
• A shift from using a word in only one particular
  situation to using the word when its reference
  occurs in a different situation
• Requires that infants distinguish between the
  reference of a word and the context in which
  occurs

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First Words

• For example, catch
• Initially used in the context of throwing an
  object to someone else
• Decontextualized use when someone throws to
  someone else, to request someone to throw an
  object, etc.

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Lexical Development

• Once child begins to talk, its vocabulary and
  usage expands dramatically and quickly
• Acquiring words is easier than attributing them
  with the right meaning

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Lexical Development

• By 18 months, infant typically has on average 50
  words it can produce and 100 words it can
  understand

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Lexical Development

• Answering Questions
• Whats That?
• Whos That?
• Asking Questions
• What? (what is that)
• Where?
• Comments
• Gone (empty cup)
• Hot (pot on stove)
• Cut (band-aid on daddy)

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Lexical Development

• Errors in first words usage
• Overextensions
• Using Daddy for every male
• More common in production than comprehension
• Underextensions
• Using Duck for a toy duck but not a real one

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First Word Combinations

• Occurs around age 2
• Tend to leave out fillers
• Mommy apron
• Types of combination seem to be common across
  languages

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First Word Combinations

• Combination Rules
• Pivotal rules -- pivot words are combined with
  names of objects, actions, or attributes
• Allgone Juice
• More Milk
• Categorical Rules -- names from category (agents,
  actions, etc.) with names from another category
  (objects, locations, etc.)
• Mommy Sock
• Book Table

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Grammar Development

• Even the two word sentences follow certain rules
• For example, one word may always be first as the
  second word changes
• Even as sentences grow to three and four words,
  they can be characterized as telegraphic speech
• They leave out fillers (a, the, and)