Lecture 4: Language Acquisition + Development

• What is a unique characteristic of human language?

  Language is specific to humans
• Why can't chimpanzees develop human-like language?


  They cannot develop a language like human language
• What is the generative power of language?


  Using a finite set of words to create an infinite number of sentences
• What are the components of language development?

  • Phonological Development
  • Semantic Development
  • Syntactic Development
  • Pragmatic Development
• What does phonological development involve?


  Acquisition of the sound system of the language
• What are phonemes?


  Individual elements of sound that make up words
• How do phonemes distinguish meaning in words?


  By changing the initial sound, as in 'pot' vs 'cot'
• How many phonemes does English use?


  Around 40 different phonemes
• Why do Japanese speakers not distinguish between /l/ and /r/?


  These phonemes do not carry different meanings in Japanese
• What is prosody in language?


  The rhythm, tempo, cadence, melody, and intonation pattern used in speech
• What does semantic development involve?


  Acquisition of meaning in a language, including word learning
• What is a morpheme?


  The smallest part of a word with meaning
• How many morphemes are in the word 'chairs'?


  Two morphemes
• What are morphological rules?


  A set of rules that specifies how morphemes combine to form words
• What does syntactic development involve?


  Acquisition of the grammar of a language
• What is syntax?


  A set of rules that specifies how words can be combined to form sentences
• How does word order affect meaning in English?


  It determines meaning, as in 'Jan saw Peter' vs 'Peter saw Jan'
• How is word order different in German compared to English?


  German word order is free
• What does pragmatic development involve?


  Acquisition of how a language is used in a particular society
• How can the phrase "Can you open the window?" be interpreted?

  As a request or as a question about ability
• What are the stages of language development?


  • 0 months: Cry
  • 1-5 months: Early perception
  • 5-8 months: Early sounds - babbling
  • 10 months: Understand about 30 words
  • 14-16 months: One word stage
  • 18-24 months: Two word stage
  • 36 months onwards: Grammar explosion
• What can babies do at 1-5 months?


  Discriminate between sounds
• What is the first stage of language development?

  Crying
• What happens during the babbling stage (5-8 months)?


  The child starts producing the sounds of language
• At what age do babies understand about 30 words?


  10 months
• What is the spoken vocabulary of a child at 14-16 months?


  Around 50 words
• What is the spoken vocabulary of a child at 24 months?


  Around 320 words
• What happens during the grammar explosion stage (36 months onwards)?


  Children rapidly add inflections and use function words
• How many words do educated adults have in their vocabulary?

  Around 40,000 to 50,000 words
• What are the sources of individual differences in language development?


  • Differing rates of development
  • Late talkers
  • Developmental language disorder
  • Hearing impairments
  • Psychosocial deprivation
  • Brain injury/trauma
  • Genetic/neurodevelopmental disorders
• What characterizes the linguistic and cognitive profile in Down syndrome?


  It is often characterized as 'uneven'
• What is the typical delay in babbling for children with Down syndrome?


  Slight delay in babbling
• At what age do children with Down syndrome typically say their first words?


  About 21 months
• How does expressive language in Down syndrome compare to receptive language?


  Expressive language lags behind receptive language
• What are the developmental trajectories in language development debates?

  • Nativist view (Chomsky, Pinker, Fodor)
  • Neuroconstructivist view (Karmiloff-Smith)
• What is the role of Infant-Directed Talk/Speech (IDT/IDS)?


  • Used by adults and children when speaking to babies
  • Helps emphasize word and phrase boundaries
  • Not used in all cultures
• What are the characteristics of Infant-Directed Speech/Talk (IDT/IDS)?


  Warm emotional tone, exaggeration, higher voice, slow talk, longer pauses, exaggerated facial expressions
• What is the preference of infants regarding speech types?

  Infants prefer IDT/IDS over other types of speech
• What did Werker et al. (1994) study about infants?


  Infants prefer to listen to a mother talking to her baby
• What was the age range of participants in Werker et al. (1994) study?


  1. 5 and 9.0 months