This project focuses on the link between speech perception and language acquisition. It will explore the efficiency of the phonological learning mechanisms in hard of hearing children. Current research in psycholinguistics shows that normal-hearing young children are born with extraordinary speech perception capacities. They learn an astonishing number of sound regularities in their native language within the first year of life. These regularities, in turn, facilitate the acquisition of other, more abstract aspects of language, like vocabulary and syntax, a process called “phonological bootstrapping”. For example, in order to segment the continuous speech stream into word units and to learn a first vocabulary, English infants use the predominant word stress pattern of English (the initial syllable of English words is often stressed, as in ‘WINdow’) to determine word boundaries from the age of 7 ½ months. We will study the phonological bootstrapping mechanism in the children with various hearing disorders, who have reduced speech perception capacities, to determine if impairments in their linguistic development, which often are considerable, can be explained by a failure in phonological bootstrapping. We will adapt a certain number of existing psycholinguistic experiments for hearing impaired children and create new ones. We will also include speech perception experiments and standardized language tests, in order to create a test battery allowing the establishment of a phonological bootstrapping profile for children with various hearing disorders. Their performances will be compared to those of their normal-hearing peers and to those of younger children, in order to determine if the linguistic development of hard of hearing children is only delayed or qualitatively different. This new phonological bootstrapping profile will also be useful for other populations with linguistic difficulties, like children with specific language impairment or autism.