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Purpose: General language abilities of children with cochlear implants have been thoroughly investigated, especially at young ages, but far less is known about how well they process language in real-world settings, especially in higher grades. This study addressed this gap in knowledge by examining recognition of sentences with complex syntactic structures in backgrounds of speech babble by adolescents with cochlear implants, and peers with normal hearing. Design: Two experiments were conducted. First, new materials were developed using young adults with normal hearing as the normative sample, creating a corpus of sentences with controlled, but complex syntactic structures presented in three kinds of babble that varied in voice gender and number of talkers. Second, recognition by adolescents with normal hearing or cochlear implants was examined for these new materials and for sentence materials used with these adolescents at younger ages. Analyses addressed three objectives: (1) to assess the stability of speech recognition across a multiyear age range; (2) to evaluate speech recognition of sentences with complex syntax in babble; and (3) to explore how bottom-up and top-down mechanisms account for performance under these conditions. Results: Results showed: (1) Recognition was stable across the ages of 10-14 years for both groups. (2) Adolescents with normal hearing performed similarly to young adults with normal hearing, showing effects of syntactic complexity and background babble; adolescents with cochlear implants showed poorer recognition overall, and diminished effects of both factors. (3) Top-down language and working memory primarily explained recognition for adolescents with normal hearing, but the bottom-up process of perceptual organization primarily explained recognition for adolescents with cochlear implants. Conclusions: Comprehension of language in real-world settings relies on different mechanisms for adolescents with cochlear implants than for adolescents with normal hearing. A novel finding was that perceptual organization is a critical factor.

Purpose: In spite of improvements in language outcomes for children with hearing loss (HL) arising from cochlear implants (CIs), these children can falter when it comes to academic achievement, especially in higher grades. Given that writing becomes increasingly relevant to educational pursuits as children progress through school, this study explored the hypothesis that one challenge facing students with CIs may be written language. Method: Participants were 98 eighth graders: 52 with normal hearing (NH) and 46 with severe-to-profound HL who used CIs. Oral and written narratives were elicited and analyzed for morphosyntactic complexity and global narrative features. Five additional measures were collected and analyzed as possible predictors of morphosyntactic complexity: Sentence Comprehension of Syntax, Grammaticality Judgment, Expressive Vocabulary, Forward Digit Span, and Phonological Awareness. Results: For oral narratives, groups performed similarly on both morphosyntactic complexity and global narrative features; for written narratives, critical differences were observed. Compared with adolescents with NH, adolescents with CIs used fewer markers of morphosyntactic complexity and scored lower on several global narrative features in their written narratives. Adolescents with NH outperformed those with CIs on all potential predictor measures, except for Sentence Comprehension of Syntax. Moderately strong relationships were found between predictor variables and individual measures of morphosyntactic complexity, but no comprehensive pattern explained the results. Measures of morphosyntactic complexity and global narrative features were not well correlated, suggesting these measures are assessing separate underlying constructs. Conclusions: Adolescents with CIs fail to show writing proficiency at high school entry equivalent to that of their peers with NH, which could constrain their academic achievement. Interventions for children with CIs need to target writing skills, and writing assessments should be incorporated into diagnostic assessments.

Purpose: Better auditory prostheses and earlier interventions have led to remarkable improvements in spoken language abilities for children with hearing loss (HL), but these children often still struggle academically. This study tested a hypothesis for why this may be, proposing that the language of school becomes increasingly disconnected from everyday discourse, requiring greater reliance on bottom-up phonological structure, and children with HL have difficulty recovering that structure from the speech signal. Participants: One hundred nineteen fourth graders participated--48 with normal hearing (NH), 19 with moderate losses who used hearing aids (HAs), and 52 with severe-to-profound losses who used cochlear implants (CIs). Method: Three analyses were conducted. (1) Sentences with malapropisms were created, and children's abilities to recognize them were assessed; (2) Factors contributing to those abilities were evaluated, including phonological awareness, phonological processing, vocabulary, verbal working memory, and oral narratives; and (3) Teachers' ratings of students' academic competence were obtained, and factors accounting for those ratings were evaluated, including the five listed above, along with word reading and reading comprehension. Results: (1) Children with HAs and CIs performed more poorly on malapropism recognition than children with NH, but similarly to each other; (2) All children with HL demonstrated large phonological deficits, but they were especially large for children with CIs. Phonological awareness explained the most variance in malapropism recognition for children with CIs. Vocabulary knowledge explained malapropism recognition for children with NH or HAs, but other factors also contributed; and (3) Teachers rated academic competence for children with CIs more poorly than for children with NH or HAs, and variance in those ratings for children with CIs were primarily explained by malapropism scores. Conclusion: Children with HL have difficulty recognizing acoustic--phonetic detail in the speech signal, and that constrains their abilities to follow conversations in academic settings, especially if HL is severe enough to require CIs.

Purpose: It is well recognized that adding the visual to the acoustic speech signal improves recognition when the acoustic signal is degraded, but how that visual signal affects postrecognition processes is not so well understood. This study was designed to further elucidate the relationships among auditory and visual codes in working memory, a postrecognition process. Design: In a main experiment, 80 young adults with normal hearing were tested using an immediate serial recall paradigm. Three types of signals were presented (unprocessed speech, vocoded speech, and environmental sounds) in three conditions (audio-only, audio-video with dynamic visual signals, and audio-picture with static visual signals). Three dependent measures were analyzed: (a) magnitude of the recency effect, (b) overall recall accuracy, and (c) response times, to assess cognitive effort. In a follow-up experiment, 30 young adults with normal hearing were tested largely using the same procedures, but with a slight change in order of stimulus presentation. Results: The main experiment produced three major findings: (a) unprocessed speech evoked a recency effect of consistent magnitude across conditions; vocoded speech evoked a recency effect of similar magnitude to unprocessed speech only with dynamic visual (lipread) signals; environmental sounds never showed a recency effect. (b) Dynamic and static visual signals enhanced overall recall accuracy to a similar extent, and this enhancement was greater for vocoded speech and environmental sounds than for unprocessed speech. (c) All visual signals reduced cognitive load, except for dynamic visual signals with environmental sounds. The follow-up experiment revealed that dynamic visual (lipread) signals exerted their effect on the vocoded stimuli by enhancing phonological quality. Conclusions: Acoustic and visual signals can combine to enhance working memory operations, but the source of these effects differs for phonological and nonphonological signals. Nonetheless, visual information can support better postrecognition processes for patients with hearing loss., By now, it is quite apparent that the visual speech signal can support the detection of acoustic speech signals at poorer signal-to-noise levels than is possible when it is not [...]

Purpose: Parental language input (PLI) has reliably been found to influence child language development for children at risk of language delay, but previous work has generally restricted observations to the preschool years. The current study examined whether PLI during the early years explains variability in the spoken language abilities of children with hearing loss at those young ages, as well as later in childhood. Participants: One hundred children participated: 34 with normal hearing, 24 with moderate losses who used hearing aids (HAs), and 42 with severe-to-profound losses who used cochlear implants (CIs). Mean socioeconomic status was middle class for all groups. Children with CIs generally received them early. Method: Samples of parent--child interactions were analyzed to characterize PLI during the preschool years. Child language abilities (CLAs) were assessed at 48 months and 10 years of age. Results: No differences were observed across groups in how parents interacted with their children. Nonetheless, strong differences across groups were observed in the effects of PLI on CLAs at 48 months of age: Children with normal hearing were largely resilient to their parents' language styles. Children with HAs were most influenced by the amount of PLI. Children with CIs were most influenced by PLI that evoked child language and modeled more complex versions. When potential influences of preschool PLI on CLAs at 10 years of age were examined, those effects at preschool were replicated. When mediation analyses were performed, however, it was found that the influences of preschool PLI on CLAs at 10 years of age were partially mediated by CLAs at preschool. Conclusion: PLI is critical to the long-term spoken language abilities of children with hearing loss, but the style of input that is most effective varies depending on the severity of risk for delay.

Purpose: Child phonologists have long been interested in how tightly speech input constrains the speech production capacities of young children, and the question acquires clinical significance when children with hearing loss are considered. Children with sensorineural hearing loss often show differences in the spectral and temporal structures of their speech production, compared to children with normal hearing. The current study was designed to investigate the extent to which this problem can be explained by signal degradation. Method: Ten 5-year-olds with normal hearing were recorded imitating 120 three-syllable nonwords presented in unprocessed form and as noise-vocoded signals. Target segments consisted of fricatives, stops, and vowels. Several measures were made: 2 duration measures (voice onset time and fricative length) and 4 spectral measures involving 2 segments (1st and 3rd moments of fricatives and 1st and 2nd formant frequencies for the point vowels). Results: All spectral measures were affected by signal degradation, with vowel production showing the largest effects. Although a change in voice onset time was observed with vocoded signals for /d/, voicing category was not affected. Fricative duration remained constant. Conclusions: Results support the hypothesis that quality of the input signal constrains the speech production capacities of young children. Consequently, it can be concluded that the production problems of children with hearing loss--including those with cochlear implants--can be explained to some extent by the degradation in the signal they hear. However, experience with both speech perception and production likely plays a role as well.

Purpose: This study assessed phonological, lexical, and morphosyntactic abilities at 6th grade for a group of children previously tested at 2nd grade to address 4 questions: (a) Do children with cochlear implants (CIs) demonstrate deficits at 6th grade? (b) Are those deficits greater, the same, or lesser in magnitude than those observed at 2nd grade? (c) How do the measured skills relate to each other? and (d) How do treatment variables affect outcome measures? Participants: Sixty-two 6th graders (29 with normal hearing, 33 with CIs) participated, all of whom had their language assessed at 2nd grade. Method: Data are reported for 12 measures obtained at 6th grade, assessing phonological, lexical, and morphosyntactic abilities. Between-groups analyses were conducted on 6th-grade measures and the magnitude of observed effects compared with those observed at 2nd grade. Correlational analyses were performed among the measures at 6th grade. Cross-lagged analyses were performed on specific 2nd- and 6th-grade measures of phonological awareness, vocabulary, and literacy to assess factors promoting phonological and lexical development. Treatment effects of age of 1st CI, preimplant thresholds, and bimodal experience were evaluated. Results: Deficits remained fairly consistent in type and magnitude across elementary school. The largest deficits were found for phonological skills and the least for morphosyntactic skills, with lexical skills intermediate. Phonological and morphosyntactic skills were largely independent of each other; lexical skills were moderately related to phonological skills but not morphosyntactic skills. Literacy acquisition strongly promoted both phonological and lexical development. Of the treatment variables, only bimodal experience affected outcomes and did so positively. Conclusions: Congenital hearing loss puts children at continued risk of language deficits, especially for phonologically based skills. Two interventions that appear to ameliorate that risk are providing a period of bimodal stimulation and strong literacy instruction.

Purpose: Verbal working memory in children with cochlear implants and children with normal hearing was examined. Participants: Ninety-three fourth graders (47 with normal hearing, 46 with cochlear implants) participated, all of whom were in a longitudinal study and had working memory assessed 2 years earlier. Method: A dual-component model of working memory was adopted, and a serial recall task measured storage and processing. Potential predictor variables were phonological awareness, vocabulary knowledge, nonverbal IQ, and several treatment variables. Potential dependent functions were literacy, expressive language, and speech-in-noise recognition. Results: Children with cochlear implants showed deficits in storage and processing, similar in size to those at second grade. Predictors of verbal working memory differed across groups: Phonological awareness explained the most variance in children with normal hearing; vocabulary explained the most variance in children with cochlear implants. Treatment variables explained little of the variance. Where potentially dependent functions were concerned, verbal working memory accounted for little variance once the variance explained by other predictors was removed. Conclusions: The verbal working memory deficits of children with cochlear implants arise due to signal degradation, which limits their abilities to acquire phonological awareness. That hinders their abilities to store items using a phonological code.

Purpose: For half a century, psycholinguists have been exploring the idea that developmental language disorders may have their roots in suprathreshold auditory dysfunctions, but results are inconclusive. Typical studies focus on relationships between temporal processing abilities and measures of various language skills at the time of testing, a proximal account. This study expanded that focus by testing three novel hypotheses: (a) Spectral processing impairments may be more responsible for language-learning deficits than temporal processing impairments. (b) Phonological sensitivity is likely the specific language skill most strongly affected by auditory (dys)functions. (c) Poor auditory functioning observed at young ages may wholly or partly recover, reducing the magnitude of relationship between those recovered functions and persistent language skills at older ages. Method: Sixty-six children (31 boys, 35 girls) 7-10 years of age participated: 36 with typical language and 30 with reading or speech disorder; from this sample two subsamples were designated: younger (7-8 years) and older (9-10 years) children. Four auditory measures were obtained of spectral modulation detection (0.5 and 2.0 cycles per octave) and temporal modulation detection (16 and 64 Hz). Four language measures were obtained, two lexicosyntactic and two phonological. Results: Younger children showed deficits in all auditory skills, but most strongly for spectral modulation detection at 0.5 cycles per octave; that measure was the only one for which older children showed deficits. Spectral modulation detection was the auditory function most strongly correlated with a language skill, and that language skill was phonological sensitivity. Conclusions: Early impairments in suprathreshold auditory functions, especially spectral processing, interfere with language acquisition at early stages, especially phonological sensitivity. Although auditory functions can recover to some extent, impairments in language skills persist, indicating that a distal account may more appropriately explain the relationship. [ABSTRACT FROM AUTHOR]

Purpose: This study examined the potential roles of phonological sensitivity and processing speed in age-related declines of verbal working memory. Method: Twenty younger and 25 older adults with age-normal hearing participated. Two measures of verbal working memory were collected: digit span and serial recall of words. Processing speed was indexed using response times during those tasks. Three other measures were also obtained, assessing phonological awareness, processing, and recoding. Results: Forward and reverse digit spans were similar across groups. Accuracy on the serial recall task was poorer for older than for younger adults, and response times were slower. When response time served as a covariate, the age effect for accuracy was reduced. Phonological capacities were equivalent across age groups, so we were unable to account for differences across age groups in verbal working memory. Nonetheless, when outcomes for only older adults were considered, phonological awareness and processing speed explained significant proportions of variance in serial recall accuracy. Conclusion: Slowing in processing abilities accounts for the primary trajectory of age-related declines in verbal working memory. However, individual differences in phonological capacities explain variability among individual older adults.

Purpose: Children must develop optimal perceptual weighting strategies for processing speech in their first language. Hearing loss can interfere with that development, especially if cochlear implants are required. The three goals of this study were to measure, for children with and without hearing loss: (a) cue weighting for a manner distinction, (b) sensitivity to those cues, and (c) real-world communication functions. Method: One hundred and seven children (43 with normal hearing [NH], 17 with hearing aids [HAs], and 47 with cochlear implants [CIs]) performed several tasks: labeling of stimuli from /b?/-to-/w?/ continua varying in formant and amplitude rise time (FRT and ART), discrimination of ART, word recognition, and phonemic awareness. Results: Children with hearing loss were less attentive overall to acoustic structure than children with NH. Children with CIs, but not those with HAs, weighted FRT less and ART more than children with NH. Sensitivity could not explain cue weighting. FRT cue weighting explained significant amounts of variability in word recognition and phonemic awareness; ART cue weighting did not. Conclusion: Signal degradation inhibits access to spectral structure for children with CIs, but cannot explain their delayed development of optimal weighting strategies. Auditory training could strengthen the weighting of spectral cues for children with CIs, thus aiding spoken language acquisition.

Purpose: One task of childhood involves learning to optimally weight acoustic cues in the speech signal in order to recover phonemic categories. This study examined the extent to which spectral degradation, as associated with cochlear implants, might interfere. The 3 goals were to measure, for adults and children, (a) cue weighting with spectrally degraded signals, (b) sensitivity to degraded cues, and (c) word recognition for degraded signals. Method: Twenty-three adults and 36 children (10 and 8 years old) labeled spectrally degraded stimuli from /b?/-to-/w?/ continua varying in formant and amplitude rise time (FRT and ART). They also discriminated degraded stimuli from FRT and ART continua, and recognized words. Results: A developmental increase in the weight assigned to FRT in labeling was clearly observed, with a slight decrease in weight assigned to ART. Sensitivity to these degraded cues measured by the discrimination task could not explain variability in cue weighting. FRT cue weighting explained significant variability in word recognition; ART cue weighting did not. Conclusion: Spectral degradation affects children more than adults, but that degradation cannot explain the greater diminishment in children's weighting of FRT. It is suggested that auditory training could strengthen the weighting of spectral cues for implant recipients.

Purpose: Several acoustic cues specify any single phonemic contrast. Nonetheless, adult, native speakers of a language share weighting strategies, showing preferential attention to some properties over others. Cochlear implant (CI) signal processing disrupts the salience of some cues: In general, amplitude structure remains readily available, but spectral structure less so. This study asked how well speech recognition is supported if CI users shift attention to salient cues not weighted strongly by native speakers. Method: Twenty adults with CIs participated. The /b?/-/w?/ contrast was used because spectral and amplitude structure varies in correlated fashion for this contrast. Adults with normal hearing weight the spectral cue strongly but the amplitude cue negligibly. Three measurements were made: labeling decisions, spectral and amplitude discrimination, and word recognition. Results: Outcomes varied across listeners: Some weighted the spectral cue strongly, some weighted the amplitude cue, and some weighted neither. Spectral discrimination predicted spectral weighting. Spectral weighting explained the most variance in word recognition. Age of onset of hearing loss predicted spectral weighting but not unique variance in word recognition. Conclusion: The weighting strategies of listeners with normal hearing likely support speech recognition best, so efforts in implant design, fitting, and training should focus on developing those strategies.

Purpose: Previous research has demonstrated that children weight the acoustic cues to many phonemic decisions differently than do adults and gradually shift those strategies as they gain language experience. However, that research has focused on spectral and duration cues rather than on amplitude cues. In the current study, the authors examined "amplitude rise time" (ART; an amplitude cue) and "formant rise time" (FRT; a spectral cue) in the /"ba"/--/"wa"/ manner contrast for adults and children, and related those speech decisions to outcomes of nonspeech discrimination tasks. Method: Twenty adults and 30 children (ages 4--5 years) labeled natural and synthetic speech stimuli manipulated to vary ARTs and FRTs, and discriminated nonspeech analogs that varied only by ART in an AX paradigm. Results: Three primary results were obtained. First, listeners in both age groups based speech labeling judgments on FRT, not on ART. Second, the fundamental frequency of the natural speech samples did not influence labeling judgments. Third, discrimination performance for the nonspeech stimuli did not predict how listeners would perform with the speech stimuli. Conclusion: Even though both adults and children are sensitive to ART, it was not weighted in phonemic judgments by these typical listeners. (Contains 5 figures and 2 tables.)

Although children with language impairments, including those associated with reading, usually demonstrate deficits in phonological processing, there is minimal agreement as to the source of those deficits. This study examined two problems hypothesized to be possible sources: either poor auditory sensitivity to speech-relevant acoustic properties, mainly formant transitions, or enhanced masking of those properties. Adults and 8-year-olds with and without phonological processing deficits (PPD) participated. Children with PPD demonstrated weaker abilities than children with typical language development (TLD) in reading, sentence recall, and phonological awareness. Dependent measures were word recognition, discrimination of spectral glides, and phonetic judgments based on spectral and temporal cues. All tasks were conducted in quiet and in noise. Children with PPD showed neither poorer auditory sensitivity nor greater masking than adults and children with TLD, but they did demonstrate an unanticipated deficit in category formation for nonspeech sounds. These results suggest that these children may have an underlying deficit in perceptually organizing sensory information to form coherent categories. (Contains 8 tables and 3 figures.)

Research Design;Intervention;Biology;Biotechnology;Teaching Methods;Hands on Science;Professional Development;Comparative Analysis;Genetics;Evaluation;Pretests Posttests;Control Groups;Science Education;Science Instruction;Pedagogical Content Knowledge

Much of speech perception research has focused on brief spectro-temporal properties in the signal, but some studies have shown that adults can recover linguistic form when those properties are absent. In this experiment, 7-year-old English-speaking children demonstrated adultlike abilities to understand speech when only sine waves (SWs) replicating the 3 lowest resonances of the vocal tract were presented, but they failed to demonstrate comparable abilities when noise bands amplitude-modulated with envelopes derived from the same signals were presented. In contrast, adults who were not native English speakers but who were competent 2nd-language learners were worse at understanding both kinds of stimuli than native English-speaking adults. Results showed that children learn to extract linguistic form from signals that preserve some spectral structure, even if degraded, before they learn to do so for signals that preserve only amplitude structure. The authors hypothesize that children's early sensitivity to global spectral structure reflects the role that it may play in language learning. (Contains 3 tables and 3 figures.)

Purpose: It has been reported that children and adults weight differently the various acoustic properties of the speech signal that support phonetic decisions. This finding is generally attributed to the fact that the amount of weight assigned to various acoustic properties by adults varies across languages, and that children have not yet discovered the mature weighting strategies of their own native languages. But an alternative explanation exists: Perhaps children's auditory sensitivities for some acoustic properties of speech are poorer than those of adults, and children cannot categorize stimuli based on properties to which they are not keenly sensitive. The purpose of the current study was to test that hypothesis. Method: Edited-natural, synthetic-formant, and sine wave stimuli were all used, and all were modeled after words with voiced and voiceless final stops. Adults and children (5 and 7 years of age) listened to pairs of stimuli in 5 conditions: 2 involving a temporal property (1 with speech and 1 with nonspeech stimuli) and 3 involving a spectral property (1 with speech and 2 with nonspeech stimuli). An AX discrimination task was used in which a standard stimulus (A) was compared with all other stimuli (X) equal numbers of times (method of constant stimuli). Results: Adults and children had similar difference thresholds (i.e., 50% point on the discrimination function) for 2 of the 3 sets of nonspeech stimuli (1 temporal and 1 spectral), but children's thresholds were greater for both sets of speech stimuli. Conclusion: Results are interpreted as evidence that children's auditory sensitivities are adequate to support weighting strategies similar to those of adults, and so observed differences between children and adults in speech perception cannot be explained by differences in auditory perception. Furthermore, it is concluded that listeners bring expectations to the listening task about the nature of the signals they are hearing based on their experiences with those signals.