PSY2001 Lecture 4 - A/Typical Language Development

Communication

• The transmission of information between the source and a receiver using a signalling system

• Not exclusive to humans

Language

• The comprehension and use of words and sentences to convey ideas and information, which can be spoken, written or signed.

• Exclusive to humans (mostly)

Communication in non-human species

Birds, bees, apes & monkeys, dolphins & whales

Language in non-human species

Kanzi the bonobo

• Taught sign language

• Can understand English

Faculty of Language

Fitch (2010)

Among all mechanisms involved in language, there is a subset unique to humans

Faculty of Language in the Broad Sense (FLB)

• Speech perception,

• Vision

• Facial and manual control

• Memory

• Navigation

• EF

• ToM

Faculty of Language in the Narrow Sense (FLN)

• Speech and verbal production

• Hierarchical syntax

• Syntax

• Pragmatics

• Mitteilungsbedurnis

Structural aspects of language

• Phonology

• Syntax

• Semantics

• Pragmatics

Phonology

Interpretation of speech sounds in a particular language

• Phoneme - smallest unit that can change the meaning of a word

Semantics

Concerned with meaning

• Includes words (lexical knowledge) and word combinations

Pragmatics

Appropriate and effective communication

• Knowing how to use language appropriately in social situations

Syntax

The structure of sentences

• Function words: (and, the, in, of, from) aid understanding of sentence

Phonetics

The production and perception of speech sounds in any language, concerned with the acoustics and articulation of those sounds

• Phone: Speech sound

Phonology of English

Modern English alphabet has 26 letters but many more sounds

Examples:

• /t/ + /h/ = th

• Three vs there

• This vs thin

Word

• An arbitrary signal that refers to a particular concept

• Contains form and meaning

• Types of words: nouns, verbs, adjectives etc.

• Probably the primary object of speech perception

Morphology

Structure of a given language's morphemes

Morpheme: smallest unit of linguistic meaning or function

Example:

• Sheep and dog

• Sheepdog

• Sheepdogs

Word learning biases - whole object constraint

Words refer to whole object rather than parts of object

Word learning biases - Shape bias

• Generalise to other objects that are the same shape rather than other attributes (texture, colour, material etc.)

• Aids early noun learning

Barrett’s Multi-Route Model

• Referential words: used in a veriety of contexts

  • Mapped on to a mental representation of objects or actions

• Context-bound words: only specific content

  • Mapped onto global construction of the event

  • Gradually analyse into individual categories (people, objects, actions, relations)

Gleitman’s syntactic boot-strapping hypothesis

Sensitive to syntactic and semantic correspondences from early age

• Extract meanings of new words from syntactic clues

  • # of “noun phrase” arguments or participants

    • Mary kicked the ball (transitive: subject + object)

    • Tom is sleeping (intransitive: subject, no object)

Studying semantic development

Observational studies of spontaneous speech

Look for particular patterns or structures (“sheeps”)

Artificial language in experiments

• Look! Cookie monster is “gorping” at Big Bird

• Look! Cookie monster and Big Bird are “gorping”

• Measure looking times at 2 different videos

• Children look longer at appropriate video.

Three key aspects of pragmatics

• Using language for different purposes

  • E.g. requesting vs demanding

• Changing language according to the needs of a listener or situations

  • E.g. Adult vs child, friend vs the King

• Following rules for conversations and storytelling

  • E.g. Staying on topic and turn-taking

Semantic development - receptive knowledge

Comprehension

• 6+ months

• 4+ years: understand jokes, riddles, double meanings etc

Semantic development - expressive knowledge

Production

• 10-12 months: first word – usually nouns

• 12-18 months: one-word stage

• ~18 months: approx. 50 words

• 18-22 months: vocabulary spurt - 50-300 words

  • Largely nouns and adjectives e.g. teddy dancing, but function words omitted e.g. my teddy is dancing

• 2-6 years: vocabulary continues to increase

Syntactical development - grammar (18-24 months)

2-word stage

• Move from word-gesture combinations to word-word combinations

• Telegraphic Speech: Only elements needed to get message across

Syntactical development - grammar (24 months+)

Longer utterances & increasing grammar,

• 3-word sentences: subject-verb-object

• ~2-3 years grammar is OK

Syntactical development - grammar (4 years)

Increasing complex grammar

• Plural = add s

• Past tense = add ed

  • Over-regularization - Applying regular rules to irregular words (Kemp & Bryant, 2003)

• Passive Voice

Development of attention, listening and understanding

• 4/5 - Understands 2-3 part spoken instructions

• 5/7 - Is aware when a message is unclear and comments or asks for explanation

• 7/9 - Identifies clearly when they haven’t understood

• 9/11 - Follows longer, unfamiliar instructions.

Three types of atypical development

Bishop & Norbury

Speech, language and communication difficulties

Speech, language and communication needs (SLCN)

• Wide age range; wide range of severity

• Mild delay in one or more areas; short-term

  • Support – catch up with peers

• Long-term and persistent

  • Direct and specific intervention (SLT)

• Pattern and impact changes over time

Devlopmental language disorder

• Difficulty in one or many of the language areas (Leonard, 1998; van der Lely, 1996; van der Lely & Battell, 2003; van der Lely & Christian, 2000).

• The most prevalent type of Special Educational Need (SEN).

St Clair et al

• Children with DLD/SLI assessed at multiple times between age 7 and 16

• Reading accuracy in individuals with DLD/ SLI develops in parallel to TD children.

  • But ability is consistently lower than TD peers.

Impacts of DLD on social relationships

• Social problems - the importance of pragmatics and turn-taking.

• Poor emotional wellbeing - loneliness.