Who proposed the input hypothesis in language acquisition?

The input hypothesis is a key concept in second language acquisition proposed by Stephen Krashen. Krashen's theory posits that language learners acquire language most effectively when they are exposed to language input that is slightly beyond their current proficiency level, a concept he refers to as "i+1." This idea emphasizes the importance of comprehensible input for language acquisition, suggesting that learners need to understand some of the language they hear or read in order to internalize it effectively. This hypothesis has had a significant influence on language teaching methodologies, highlighting the essential role of meaningful interaction in language learning.

The other individuals listed have made important contributions to the fields of linguistics and psychology, but they are not associated with the input hypothesis. Noam Chomsky is known for his theories on universal grammar and the innate aspects of language acquisition. Lev Vygotsky focused on social interaction and the role of culture in cognitive development, particularly through his concepts of the zone of proximal development. James Asher is known for the Total Physical Response method in language learning but did not propose the input hypothesis.