Lecture 5 - Theories & Diversity of Language Development Flashcards
What are the internal and external factors involved in language development?
- Internal: Biological and cognitive factors (e.g., genes, brain development)
- External: Environmental input and social context (Bronfenbrenner’s Bioecological Model, 1979)
- Language development is shaped by their interaction over time
What is Bronfenbrenner’s Bioecological Model (1979) in relation to language development?
- This model views development as influenced by multiple environmental systems interacting with biology over time
- It highlights that language development depends not only on genetics but also on the quality of linguistic and social input
What is the significance of the FOXP2 gene in language research?
- Discovered through the KE family with speech and language impairments (Fisher et al.)
FOXP2 is a transcription factor, affecting 1000 other genes - It is not a “language gene” but is crucial for motor sequencing (e.g., coordinating speech movements)
- Found in birds (linked to song learning), mice (motor control), and humans (speech deficits in KE family)
What does FOZP2 research suggest about language development?
- Supports nature (innate ability) view (Pinker), but..
- Also shows domain-general functions (e.g., rhythm perception, fine motor control), supporting a broader learning model (Gopnik)
What did the research on Kanzi and Chaser reveal about animal communication?
- Kanzi the bonobo: Used symbols and gestures to communicate; showed some understanding of grammar
- Chaser the border collie (Kaminski et al., 2004): Learned >1000 object names but lacked categorical generalisation (treated each word as a unique label)
- Highlights key differences between human and non-human language learning (e.g., abstraction, generativity)
What does the Swiss army knife metaphor (Cosmides & Tooby, 1994) represent in developmental psychology? What idea does it support?
- It illustrates the idea of domain-specific cognitive modules, each adapted for a particular function
- In language, it supports the idea that the infant brain may be pre-specified for language processing
How do adult neuropsychological models support modularity?
- Adults: Specific deficits (e.g., agrammatism, prosopagnosia) support brain modularity
- Children: Dissociations in genetic disorders (e.g., SLI vs. Williams Syndrome) suggest innate, distinct modules for language and other abilites
What was revealed in the case of the man with hydrocephalus (Feuillet et al., 2007)?
- Despite having severely reduced brain tissue, he had a functional life and verbal IQ of 85
- Suggests neuroplasticity and the brain’s ability to adapt functionally over time
What are the major stages of brain development? (Thompson. & Nelson, 2001)?
- Neurulation: 18-24 prenatal days
- Cell migration: Birth to 2 years
- Myelination: Begins prenatally (-2 months). and continues until 10 years
- Synaptogenesis: Begins prenatally, peaks at 2 years, continues into adolescence
- Neurogenesis in hippocampus: From conception to adulthood
What are the language and cognitive profiles of individuals with Williams Syndrome (WS)?
- Caused by the deletion of 26 genes at 7q11.23
- Language abilities: Relatively proficient
- Visuospatial, numerical, and problem-solving abilities: Significantly impaired
- Social cognition: Often relatively strong
- Demonstrates genetic dissociation: Language may be spared despite global cognitive impairment (pinker, 1999)
What does the dynamic developmental approach suggest about WS? (Karmiloff-Smith, 1998)
- Development in WS is atypical from the outset, with brain volume, structure, and chemistry all altered
- It is not a normal system with isolated defects: developmental pathways are different, leading to cascading effects.
How can non-linguistic factors impact language development?
- Includes: Motor skills, memory, attention, intention understanding, pattern recognition
- Bradshaw et al. (2022): Example of motor-sitting cascade - motor milestones affect caregiver interaction, which affects language
What are some examples of environmental effects on language development?
- Genie (severe deprivation)
- Deaf children of hearing parents not exposed to sign language
- 30 million word gap by age 3 (Hart & Ridley, 1995): High-income children hear 2x more words than low-income peers
What did Johnson & Newport (1989) find about second language acquisition? How did they do it?
- Studied Korean/Chinese speakers who learned English at different ages
- Before age 7: Native-like grammar
- After age 11: Gradual decline in grammatical accuracy
- Supports the Sensitive Period Hypothesis (biological window for optimal language learning)
What is the language profile of children with Down syndrome?
- Lower MLU (mean length of utterance) than typically developing peers
- D’Souza et al.: Deficits in expressive/receptive language relative to motor and visual skills
- Often have greater difficulty with syntax and morphology
How does parental mental health impact with language development in children with Down syndrome?
- D’Souza et al., 2020: Higher parental depression correlates with lower expressive vocabulary in children
- Highlights interaction of internal and external factors
