Language DevelopmentLecture Notes: 11/11/14The Role of SES in Language Development● Children from disadvantaged families start kindergarten with lower language and cognitive skills than those from more advantaged families● 65% of low-SES preschoolers in Head Start programs have clinically significant language delays● What is it about low SES that is so bad for language development?○ Physical conditions?○ Access to resources?○ Quality of input?Types of Hearing Loss● Prelingual/Postlingual○ Prelingual = typically occurs congenitally (from birth) or before the child has learned language○ Postlingual= occurs after the child has acquired language■ Common in elderly people● Mild/Moderate/ProfoundPhonological Development and Hearing Loss● Babbling○ Around 6-7 months, when hearing babies start vocal play, and start babbling, deaf children will stop vocalizing● Articulation difficulties○ Especially for high-frequency sounds (e.g., s and z)○ Sounds that are difficult to hear get omitted (e.g., word-final consonants; individual consonants in consonant clusters)● Prosody (intonation is very distinctive = speech sounds “choppy”, not fluid○ Likely due to difficulty with co-articulating words and soundsLexical Development and Hearing Loss● Words are learned through exposure● If limit exposure, limit the vocabulary● Children who are deaf cannot learn vocabulary by “overhearing” it in the context it is used● Instead, have to be taught words explicitly, in the classroom/instructionalGrammatical Development and Hearing Loss● Difficulty hearing makes it difficult to parse words into their morphological components● Difficulty with auxiliaries, infinitives, and gerunds● Typically, use very simple syntax (SVO)Reading Development and Hearing Loss● Remember the two key skills to reading development?○ Phonological awareness○ Vocabulary knowledge● Both are difficult for children who are deaf● By some estimates, reading abilities of deaf students do not rise beyond third-grade level● Made more difficult by emphasis on very simple grammar in school, but reading at 4th grade level requires comprehension of complex, long sentences Management of Hearing Impairment● Early identification● Assistive technology● Therapy and schoolingAssistive Technology● Assistive Listening Devices○ Amplify the environment input (used with phones, in movie theatres, etc.)● Hearing aides○ Amplify the environmental input and send the signal to the ear● Cochlear implants○ Implantable electrode arrays that stimulate the auditory nerve directly○ Implanted very early (as early as 12 months)○ Not a panacea = there is great variability in success rates (due to many factors, such as age at implantation, unilater/bilater implantation, exposure to sign, educational support, etc…)Speechreading● = lipreading● Figuring out sounds based on the speaker’s mouth movements● In hearing children and adults, being able to combine visual (mouth) and auditory (sound) cues helps in recognizing speech● McGurk Effect● Difficult to do without the auditory information: some sounds look the same, but sound different (e.g., p vs m); some sounds are not visible (velar k and g)Acquisition of ASL as the Native Language● ASL is processed by the same brain regions as oral language (vs. gestures)● Same developmental stages as with oral languages● Deaf babies of deaf parents babble with their hands in the same rhythmic, repetitive fashion as hearing infants who babble with their voices● Exposure to ASL early on facilitates acquisition of oral language later on○ Hearing children born to deaf parents○ Children exposed to ASL from birth were better able to acquire oral language than children not exposed to ASL from birth● Language is language● Exposure to a symbolic system facilitates subsequent acquisition of another symbolic systemManual English vs. Sign Language● Manual English was developed to help in acquisition of an oral language● Translates English construction word-for-word● Adapts ASL signs for vocabulary, and uses invented signs for English grammatical components not encoded by ASL (e.g. articles)● Duplicates English syntax, instead of using ASL word order● Is being weaned out in most educational