Nature vs. Nurture

Nature View

The child comes heavily “wired” to perform the task of acquiring language

Nurture View

Observable, environmental factors explain language acquisition

Interactionist View

Hybrid of Nature and Nurture views

The 3 Nature Theories

Transformational Grammar, Biological Bases, Contemporary View

Transformational Grammar

Noam Chomsky described the innate knowledge that enables a native speaker to produce a potentially infinite number of novel utterances. The innate language component is called the Language Acquisition Device (LAD), armed with linguistic universals, which allows children to develop language fairly quick.

• Parents tend to correct semantic/vocabulary errors over syntax errors, and children still learn syntax

Biological Bases

Eric Lenneberg supported the view that language is biologically based with evidence of 1) all languages being characterized by the same domains, 2) the universal timeline for language acquisition, 3) heredity, 4) no evidence of primitive languages in other species

Support for Biological Bases

• cerebral assymetries

• critical period for speech and language development

• speech perception in infancy

• CNS development

• genetic evidence of language problems

Contemporary View

Pinker and Jackendoff argued that specialized language facilities trigger the development of linguistic knowledge.

• Asked question: What are the innate mechanisms necessary for language learning to take place?

  • specific cognitive skills

  • metacognitive control that monitors incoming stimuli, motor output

  • theory of mind - the ability to attribute states to others that are different from your own (beliefs, desires, knowledge of oneself)

Cognitive skills

The ability to represent objects with ideas mentally

Limitations of Nature View

• Recent evidence shows that caretakers do respond to children’s language errors

• The assumption that language acquisition is completed at ages 4-5 has not been supported

• The critical period for language acquisition has not been clearly identified

• The nature argument alone is not sufficient to explain language development based on the evidence gathered so far

• The notion that language is acquired through a species specific LAD device is controversial; it has not been found in the brain

Nature View: Implications for Assessment

• Describe children’s knowledge of morphology and syntax

• Measure progress relative to MLU

• Use of samples of spontaneous language as the data to determine children’s linguistic knowledge

Nature View: Implications for Intervention

• Goals of language are written based on inferences about what the children had to learn about their language rules, and what they were ready to learn given their stage of language acquisition

• Emphasis on expanding the child’s MLU, use of various sentence types, and the use of Brown’s 14 grammatical morphemes

MLU

Mean length of utterance

Behaviorist Approach in Nurture Theories

• Focuses on observable environmental conditions (stimuli) that co-occur and predict specific verbal behaviors (responses)

• Behaviorists focus on learning because language is seen as a skill, like any other behavior

• Speaking is assumed to be learned through reinforcement, imitation, and successive approximations to mature performance (shaping)

The 3 Nurture Theories

Classical conditioning, Operant conditioning, Imitation

Classical Conditioning

Associations formed between arbitrary verbal stimuli and internal responses are cited as the source for learning; basic pairing of words to objects

Operant Conditioning

Assumes a child’s productive speech is shaped by differential reinforcers and punishments supplied by environmental agents (caretakers)

Imitation

An important factor in language learning because it allows a shortcut to mature behavior

Evidence of Nurture Theories

• Behavioral techniques, like imitation and reinforcement, are beneficial in promoting speech skills in kids with Down Syndrome, those who stutter, and those with other developmental delays

• By responding to their infant’s babbling, mothers encourage babies to babble more using the phonemes of their language

Limitations of Nurture Theories

• Stimulus-response explanations cannot explain the development of the complex system of language knowledge that the child acquires in such a short amount of time

• Does not account for observable meaning knowledge, utterance novelty, complexity and rapidity with which language was acquired

• Does not explain how children develop language disorders

Nurture View: Implications for Assessment

• Placed emphasis on observation of behavior, data-driven descriptions, quantification, and measurement

• Supported the use of standardized tests to identify deficits in all areas of language

Nurture View: Implications for Intervention

• SLPs use of behavioral programs

• Applied behavior analysis, an outgrowth of operant conditioning, is commonly used to enhance language development - particularly in children with autism

Interactionist Theories

Cognitive-Constructivist Models, Social-Cognitive Models

Cognitive-Constructivist Model

• From a Piagetian perspective, learning is accomplished throughout the lifespan by the active participation of infants, children, and adults (such as learning through play)

• The traditional Piagetian view maintains that a direct relationship exists between cognitive achievements and later linguistic attainments

Evidence for Cognitive-Constructivist Model

• Vocabulary spurt seen at the end of the second year coincides with the last stage of sensorimotor development

• Development of disappearance words (“all gone”) is related to object permanence acquisition

• Success and failure terms (“There!” “Uh oh”) appear around the same time as means-ends understanding

• Children begin to use 2-word utterances around the same time they put two gestures together

• Children learn action words in the context of performing those actions

Social-Cognitive Perpective

• Vygotsky believed that children’s cognitive development resulted from interaction between children’s innate skills and their social experiences with peers, adults, and the culture

  • Private Speech = When a child and an adult engage in dialogue while collaborating on a task, the information can be stored for future use and be used as a tool to guide problem-solving and other cognitive abilities

  • Zone of proximal development = Area between what a child can accomplish independently and what a child can accomplish with another person of greater knowledge, experience, and skill; this is the sweet spot for goal setting

Piaget vs. Vygotsky

Piaget - Cognitive development occurred primarily through a child’s interaction with objects

Vygotsky - Cognitive development was socially mediated

Social Pragmatic Perspective

• Halliday described the functions of his son Nigel’s non-linguistic communication: satisfying needs, controlling others, interacting, and expressing emotions and interests

• John Dore identified the primitive speech acts of children at the one-word stage: labeling, answering, requesting an action/answer, calling/greeting, protesting, repeating/imitating, and practicing

Implications of these perspectives

• Observations that adults speak differently to young children

  • Child-directed speech (motherese) - contextually redundant, slower, shorter utterances, and high pitch, more stressed speech to facilitate the segmentation of speech, which in turn leads to the discovery of phonemes and words

Implications on assessment and treatment of lanuage disorders

• Theories helped SLPs understand why children with ASD have trouble learning language (intentionality) and the functions of echolalia

• Theories emphasized the importance of gestures, facial expressions, body language, eye gaze, and listener perspective for communicative competence

• New emphasis on parent-training and intervention goals

  • pre-linguistic and nonlinguistic communication

  • conversational skills, discourse genres, communication repair, listener adaptation

  • language and conversational skills needed for peer interactions

Contemporary Thoughts

• Early experiences determine whether a child’s developing brain architecture provides a strong or weak foundation for all future learning, behavior, and health. Early intervention is necessary for those at risk.

• The interactive influences of genes and experience shape the architecture of the child’s developing brain

• Brain architecture and developmental skills are built from “bottom up”. Complex skills build on simpler ones

• Cognitive, emotional, and social capabilities are inextricably intertwined throughout the life course, and their interactive relationship develops in a continuous process over time