* The Innateness Hypothesis: This theory suggests that humans are born with an innate capacity for language. It argues that the brain has specific structures and mechanisms that are pre-wired for language acquisition.
* Deaf Children and Sign Language: Deaf children who are exposed to sign language from a young age often develop fluency and mastery of the language similar to hearing children learning spoken languages. This is significant because:
* No Exposure to Spoken Language: Deaf children learning sign language have no exposure to spoken language, demonstrating that the ability to learn language isn't tied to auditory input alone.
* Similar Development: Their language acquisition follows similar stages and patterns observed in hearing children learning spoken language, suggesting an underlying universal mechanism for language development.
* Complex Linguistic Structures: Sign languages, like spoken languages, have complex grammatical structures, syntax, and semantics. Deaf children's mastery of these features further supports the idea of an innate language faculty.
Evidence for Innateness:
The fact that deaf children can become fluent sign language users despite having no exposure to spoken language provides strong support for the innateness hypothesis. It suggests that:
* The brain is not simply a blank slate: It has a pre-existing capacity for language that can be activated by different input modalities (spoken language vs. sign language).
* Language is a core human ability: The capacity for language is not dependent on specific sensory inputs but rather on a more fundamental cognitive structure.
It's important to note:
* The nature vs. nurture debate: While the innateness hypothesis acknowledges the importance of input, it doesn't negate the role of experience. Early exposure to language, whether spoken or signed, is still crucial for language development.
* Variations in language acquisition: While deaf children learning sign language provides strong support, the innateness hypothesis is a complex topic with ongoing research and debate. There are variations in language acquisition among children, influenced by factors like socio-economic background, access to language, and individual learning styles.
In conclusion, deaf children's fluency in sign language strongly supports the innateness hypothesis by demonstrating that the human capacity for language is not tied to a specific sensory modality and may be guided by an innate, pre-wired mechanism within the brain.