Language

Language

Uniquely human, socially shared and rule-based code used to communicate concrete and abstract meanings

·       Uses sounds, symbols and gestures

·       Allows ideas, thoughts and desires to be transmitted

·       Each language has its own rules

·       Begins in oral form, but occurs through writing, gesture, drawing, etc

Animal communication

·       Communicate through sound, sight, touch and olfaction

·       Bird calls/songs and bee dances communicate info but are restricted systems

·       Dogs can associate sound sequences with commands/objects

Language components

Producing sounds

1.        Subpharyngeal system

2.        Larynx

3.        Subglottal system

Bloom and Lahey model

Language integrates:

Language vs speech

·       Problems with speech production are not automatically a problem with language

Speech motor sequence

1.        Respiration (lungs)

2.        Phonation (larynx/vocal cords)

3.        Articulation (lips, tongue, soft palate)

Production vs comprehension

·       Producing language and understanding language are separate processes

·       In child development, comprehension can be superior to production

- Early production errors may reflect simplification rather than poor understanding

Language development stages

Meaningful speech

Achieving a critical mass of words/phrases AND learning linguistic rules (grammar, morphology, phonology)

·       Once rules are learned, children can combine words and generate language rather than only imitate

·       Errors in imitation, production, meaning, tense and plurals are error-feedback loops that contribute to development

Brain changes during language development

·       Connectivity and myelination of speech zones

·       Changes in dendritic complexity, particularly in Broca's area

·       Maturation of cortical language areas plus genetic and environmental influences

·       Developmental milestones differ for multilingual children

Left hemisphere dominance

·       Dominant for language in most people

·       Language is NOT located in only two areas

Language regions

Modern view of language

·      Language is a widely distributed network

·      All lobe regions can all activate in response to words

·      Broca's and Wernicke's areas are important specialised nodes

Brain stimulation evidence

·      Stimulating parts of motor cortex can cause speech arrest

·      Stimulating parts of Broca's area can disrupt language

Left vs right hemisphere

Aphasia

Acquired impairment/loss of language caused by brain damage

·      Can affect production, comprehension or naming

Aphasia types