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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., Supplemental Material: https://doi.org/10.23641/asha.21965228.

Human language is unique among animal communication systems, in part because of its dual patterning in which meaningless phonological units combine to form meaningful words (phonological structure) and words combine to form sentences (lexicosyntactic structure). Although dual patterning is well recognized, its emergence in language development has been scarcely investigated. Chief among questions still unanswered is the extent to which development of these separate structures is independent or interdependent, and what supports acquisition of each level of structure. We explored these questions by examining growth of lexicosyntactic and phonological structure in children with normal hearing ( n = 49) and children with hearing loss who use cochlear implants ( n = 56). Multiple measures of each kind of structure were collected at 2-year intervals (kindergarten through eighth grade), and used to construct latent scores for each type of structure. Growth curve analysis assessed (a) the relative independence of development for each level of structure; (b) interactions between these two levels of structure in real-time language processing; and (c) contributions to growth of each level of structure made by auditory input, socioeconomic status (as proxy for linguistic experience), and speech motor control. Findings suggested that phonological and lexicosyntactic structure develop largely independently. Auditory input, socioeconomic status, and speech motor control help shape these language structures, with the last two factors exerting stronger effects for children with cochlear implants. Only for children with cochlear implants were interdependencies in real-time processing observed, reflecting compensatory mechanisms likely present to help them handle the disproportionately large phonological deficit they exhibit. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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.

This study tested the hypotheses that (1) adolescents with cochlear implants (CIs) experience impaired spectral processing abilities, and (2) those impaired spectral processing abilities constrain acquisition of skills based on sensitivity to phonological structure but not those based on lexical or syntactic (lexicosyntactic) knowledge. To test these hypotheses, spectral modulation detection (SMD) thresholds were measured for 14-year-olds with normal hearing (NH) or CIs. Three measures each of phonological and lexicosyntactic skills were obtained and used to generate latent scores of each kind of skill. Relationships between SMD thresholds and both latent scores were assessed. Mean SMD threshold was poorer for adolescents with CIs than for adolescents with NH. Both latent lexicosyntactic and phonological scores were poorer for the adolescents with CIs, but the latent phonological score was disproportionately so. SMD thresholds were significantly associated with phonological but not lexicosyntactic skill for both groups. The only audiologic factor that also correlated with phonological latent scores for adolescents with CIs was the aided threshold, but it did not explain the observed relationship between SMD thresholds and phonological latent scores. Continued research is required to find ways of enhancing spectral processing for children with CIs to support their acquisition of phonological sensitivity.

Background: In spite of recent gains in language development made by children with hearing loss (HL) as a result of improved auditory prostheses and earlier starts to intervention, these children continue to struggle academically at higher grade levels. We hypothesize that one reason for these incongruent outcomes for language and academics may be that the language demands of school escalate as grade level increases, outstripping the language abilities of children with HL. We tested that hypothesis by examining a higher level skill that is essential for success with academic language, the ability to access multiple interpretations for a sentence., Method: 122 children participated at the end of middle school: 56 with normal hearing (NH), 15 with moderate HL who used hearing aids (HAs), and 51 with severe-to-profound HL who used cochlear implants (CIs). Children's abilities to provide more than one interpretation for an ambiguous sentence were assessed. These sentences were ambiguous due either to words having multiple meanings or to syntactic structure that could evoke more than one interpretation. Potential predictors of those abilities were evaluated, including expressive vocabulary, comprehension of syntactic structures, grammaticality judgments, forward digit span, and several audiologic factors., Results: Children with NH performed best, children with CIs performed poorest, and children with HAs performed intermediately to those groups. Children in all groups achieved higher scores on the multiple meanings than on the syntactic structure items. The variables that were associated with performance varied across groups. Audiologic factors did not explain any variability in performance on the ambiguous sentences task for children with HL., Conclusions: The kind of linguistic flexibility needed to consider more than one interpretation for sentences lacking immediate, real-world context is essential to processing academic language. Children with HL - especially those with severe-to-profound HL who required CIs - showed deficits in this skill, which could contribute to their ongoing academic struggles. Continued language support is needed for these children to allow them to acquire the higher level language skills necessary for success through all of their years in school., (Copyright © 2020 Elsevier B.V. All rights reserved.)

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. #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. #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. Supplemental Material https://doi.org/10.23641/asha.13133018.

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: Developmental dyslexia is commonly viewed as a phonological deficit that makes it difficult to decode written language. But children with dyslexia typically exhibit other problems, as well, including poor speech recognition in noise. The purpose of this study was to examine whether the speech-in-noise problems of children with dyslexia are related to their reading problems, and if so, if a common underlying factor might explain both. The specific hypothesis examined was that a spectral processing disorder results in these children receiving smeared signals, which could explain both the diminished sensitivity to phonological structure - leading to reading problems - and the speech recognition in noise difficulties. The alternative hypothesis tested in this study was that children with dyslexia simply have broadly based language deficits., Participants: Ninety-seven children between the ages of 7 years; 10 months and 12 years; 9 months participated: 46 with dyslexia and 51 without dyslexia., Methods: Children were tested on two dependent measures: word reading and recognition in noise with two types of sentence materials: as unprocessed (UP) signals, and as spectrally smeared (SM) signals. Data were collected for four predictor variables: phonological awareness, vocabulary, grammatical knowledge, and digit span., Results: Children with dyslexia showed deficits on both dependent and all predictor variables. Their scores for speech recognition in noise were poorer than those of children without dyslexia for both the UP and SM signals, but by equivalent amounts across signal conditions indicating that they were not disproportionately hindered by spectral distortion. Correlation analyses on scores from children with dyslexia showed that reading ability and speech-in-noise recognition were only mildly correlated, and each skill was related to different underlying abilities., Conclusions: No substantial evidence was found to support the suggestion that the reading and speech recognition in noise problems of children with dyslexia arise from a single factor that could be defined as a spectral processing disorder. The reading and speech recognition in noise deficits of these children appeared to be largely independent., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

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: 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.

Objective: Cochlear implants (CIs) do not automatically restore speech recognition for postlingually deafened adults. Average word recognition remains at 60%, and enormous variability exists. Understanding speech requires knowledge of phonemic codes, the basic sound units of language. Hearing loss may result in degeneration of these long-term mental representations (i.e., "phonemic sensitivity"), and CI use may not adequately restore those representations. This investigation examined whether phonemic sensitivity is degraded for CI users, and whether this degradation results in poorer word recognition., Study Design: Thirty adults with CIs and 20 normal-hearing controls underwent testing., Methods: Participants were assessed for word recognition in quiet, along with tasks of phonemic sensitivity using an audiovisual format to maximize recognition: initial consonant choice (ICC), in which they selected the word with the same starting sound as a target word, final consonant choice (FCC), in which they selected the word with the same ending sound, and backwards words, in which they repeated phonemes comprising words in backwards order., Results: Phonemic sensitivity was poorer for CI users than for normal-hearing controls for ICC and FCC. For CI users, ICC and FCC predicted 25% and 40% of variance in word recognition, respectively. Longer duration of CI use did not lead to greater restoration in phonemic sensitivity., Conclusion: Even for adults who presumably had developed refined phonemic representations, hearing loss can degrade those representations, which results in poorer word recognition. Cochlear implants do not adequately restore those representations. Findings suggest the need for rehabilitative efforts to improve CI users' phonemic sensitivity.

Objectives: Cochlear implantation does not automatically result in robust spoken language understanding for postlingually deafened adults. Enormous outcome variability exists, related to the complexity of understanding spoken language through cochlear implants (CIs), which deliver degraded speech representations. This investigation examined variability in word recognition as explained by "perceptual attention" and "auditory sensitivity" to acoustic cues underlying speech perception., Design: Thirty postlingually deafened adults with CIs and 20 age-matched controls with normal hearing (NH) were tested. Participants underwent assessment of word recognition in quiet and perceptual attention (cue-weighting strategies) based on labeling tasks for two phonemic contrasts: (1) "cop"-"cob," based on a duration cue (easily accessible through CIs) or a dynamic spectral cue (less accessible through CIs), and (2) "sa"-"sha," based on static or dynamic spectral cues (both potentially poorly accessible through CIs). Participants were also assessed for auditory sensitivity to the speech cues underlying those labeling decisions., Results: Word recognition varied widely among CI users (20 to 96%), but it was generally poorer than for NH participants. Implant users and NH controls showed similar perceptual attention and auditory sensitivity to the duration cue, while CI users showed poorer attention and sensitivity to all spectral cues. Both attention and sensitivity to spectral cues predicted variability in word recognition., Conclusions: For CI users, both perceptual attention and auditory sensitivity are important in word recognition. Efforts should be made to better represent spectral cues through implants, while also facilitating attention to these cues through auditory training.

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 /bɑ/-to-/wɑ/ 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.

Children need to discover linguistically meaningful structures in the acoustic speech signal. Being attentive to recurring, time-varying formant patterns helps in that process. However, that kind of acoustic structure may not be available to children with cochlear implants (CIs), thus hindering development. The major goal of this study was to examine whether children with CIs are as sensitive to time-varying formant structure as children with normal hearing (NH) by asking them to recognize sine-wave speech. The same materials were presented as speech in noise, as well, to evaluate whether any group differences might simply reflect general perceptual deficits on the part of children with CIs. Vocabulary knowledge, phonemic awareness, and "top-down" language effects were all also assessed. Finally, treatment factors were examined as possible predictors of outcomes. Results showed that children with CIs were as accurate as children with NH at recognizing sine-wave speech, but poorer at recognizing speech in noise. Phonemic awareness was related to that recognition. Top-down effects were similar across groups. Having had a period of bimodal stimulation near the time of receiving a first CI facilitated these effects. Results suggest that children with CIs have access to the important time-varying structure of vocal-tract formants.

Broadened auditory filters associated with sensorineural hearing loss have clearly been shown to diminish speech recognition in noise for adults, but far less is known about potential effects for children. This study examined speech recognition in noise for adults and children using simulated auditory filters of different widths. Specifically, 5 groups (20 listeners each) of adults or children (5 and 7 yrs), were asked to recognize sentences in speech-shaped noise. Seven-year-olds listened at 0 dB signal-to-noise ratio (SNR) only; 5-yr-olds listened at +3 or 0 dB SNR; and adults listened at 0 or -3 dB SNR. Sentence materials were processed both to smear the speech spectrum (i.e., simulate broadened filters), and to enhance the spectrum (i.e., simulate narrowed filters). Results showed: (1) Spectral smearing diminished recognition for listeners of all ages; (2) spectral enhancement did not improve recognition, and in fact diminished it somewhat; and (3) interactions were observed between smearing and SNR, but only for adults. That interaction made age effects difficult to gauge. Nonetheless, it was concluded that efforts to diagnose the extent of broadening of auditory filters and to develop techniques to correct this condition could benefit patients with hearing loss, especially children.

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 /bɑ/-to-/wɑ/ 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.

The dynamic specification account of vowel recognition suggests that formant movement between vowel targets and consonant margins is used by listeners to recognize vowels. This study tested that account by measuring contributions to vowel recognition of dynamic (i.e., time-varying) spectral structure and coarticulatory effects on stationary structure. Adults and children (four- and seven-year-olds) were tested with three kinds of consonant-vowel-consonant syllables: (I) unprocessed; (2) sine waves that preserved both stationary coarticulated and dynamic spectral structure; and (3) vocoded signals that primarily preserved that stationary, but not dynamic structure. Sections of two lengths were removed from syllable middles: (I) half the vocalic portion; and (2) all but the first and last three pitch periods. Adults performed accurately with unprocessed and sine-wave signals, as long as half the syllable remained; their recognition was poorer for vocoded signals, but above chance. Seven-year-olds performed more poorly than adults with both sorts of processed signals, but disproportionately worse with vocoded than sine-wave signals. Most four-year-olds were unable to recognize vowels at all with vocoded signals. Conclusions were that both dynamic and stationary coarticulated structures support vowel recognition for adults, but children attend to dynamic spectral structure more strongly because early phonological organization favors whole words.

Purpose: This study compared perceptual weighting strategies of children with cochlear implants (CIs) and children with normal hearing (NH), and asked if strategies are explained solely by degraded spectral representations, or if diminished language experience accounts for some of the effect. Relationships between weighting strategies and other language skills were examined., Method: One hundred 8-year-olds (49 with NH and 51 with CIs) were tested on four measures: (1) labeling of cop-cob and sa-sha stimuli; (2) discrimination of the acoustic cues to the cop-cob decision; (3) phonemic awareness; and (4) word recognition., Results: No differences in weighting of cues to the cop-cob decision were observed between children with CIs and NH, suggesting that language experience was sufficient for the children with CIs. Differences in weighting of cues to the sa-sha decision were found, but were not entirely explained by auditory sensitivity. Weighting strategies were related to phonemic awareness and word recognition., Conclusions: More salient cues facilitate stronger weighting of those cues. Nonetheless, individuals differ in how salient cues need to be to capture perceptual attention. Familiarity with stimuli also affects how reliably children attend to acoustic cues. Training should help children with CIs learn to categorize speech sounds with less-salient cues., Learning Outcomes: After reading this article, the learner should be able to: (1) recognize methods and motivations for studying perceptual weighting strategies in speech perception; (2) explain how signal quality and language experience affect the development of weighting strategies for children with cochlear implants and children with normal hearing; and (3) summarize the importance of perceptual weighting strategies for other aspects of language functioning., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Cochlear implants have improved speech recognition for deaf individuals, but further modifications are required before performance will match that of normal-hearing listeners. In this study, the hypotheses were tested that (1) implant processing would benefit from efforts to preserve the structure of the low-frequency formants and (2) time-varying aspects of that structure would be especially beneficial. Using noise-vocoded and sine-wave stimuli with normal-hearing listeners, two experiments examined placing boundaries between static spectral channels to optimize representation of the first two formants and preserving time-varying formant structure. Another hypothesis tested in this study was that children might benefit more than adults from strategies that preserve formant structure, especially time-varying structure. Sixty listeners provided data to each experiment: 20 adults and 20 children at each of 5 and 7 years old. Materials were consonant-vowel-consonant words, four-word syntactically correct, meaningless sentences, and five-word syntactically correct, meaningful sentences. Results showed that listeners of all ages benefited from having channel boundaries placed to optimize information about the first two formants, and benefited even more from having time-varying structure. Children showed greater gains than adults only for time-varying formant structure. Results suggest that efforts would be well spent trying to design processing strategies that preserve formant structure.

Objective: Using signals processed to simulate speech received through cochlear implants and low-frequency extended hearing aids, this study examined the proposal that low-frequency signals facilitate the perceptual organization of broader, spectrally degraded signals., Design: In two experiments, words and sentences were presented in diotic and dichotic configurations as four-channel noise-vocoded signals (VOC-only), and as those signals combined with the acoustic signal below 0.25 kHz (LOW-plus). Dependent measures were percent correct recognition, and the difference between scores for the two processing conditions given as proportions of recognition scores for VOC-only. The influence of linguistic context was also examined., Study Sample: Participants had normal hearing. In all, 40 adults, 40 seven-year-olds, and 20 five-year-olds participated., Results: Participants of all ages showed benefits of adding the low-frequency signal. The effect was greater for sentences than words, but no effect of diotic versus dichotic presentation was found. The influence of linguistic context was similar across age groups, and did not contribute to the low-frequency effect. Listeners who had poorer VOC-only scores showed greater low-frequency effects., Conclusion: The benefit of adding a low-frequency signal to a broader, spectrally degraded signal derives in some part from its facilitative influence on perceptual organization of the sensory input.

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 /bɑ/-/wɑ/ 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.

Objective: This study examined speech recognition in noise for children with hearing loss, compared it to recognition for children with normal hearing, and examined mechanisms that might explain variance in children's abilities to recognize speech in noise., Design: Word recognition was measured in two levels of noise, both when the speech and noise were co-located in front and when the noise came separately from one side. Four mechanisms were examined as factors possibly explaining variance: vocabulary knowledge, sensitivity to phonological structure, binaural summation, and head shadow., Study Sample: Participants were 113 eight-year-old children. Forty-eight had normal hearing (NH) and 65 had hearing loss: 18 with hearing aids (HAs), 19 with one cochlear implant (CI), and 28 with two CIs., Results: Phonological sensitivity explained a significant amount of between-groups variance in speech-in-noise recognition. Little evidence of binaural summation was found. Head shadow was similar in magnitude for children with NH and with CIs, regardless of whether they wore one or two CIs. Children with HAs showed reduced head shadow effects., Conclusion: These outcomes suggest that in order to improve speech-in-noise recognition for children with hearing loss, intervention needs to be comprehensive, focusing on both language abilities and auditory mechanisms.

Developmental dyslexia is a condition in which children encounter difficulty learning to read in spite of adequate instruction. Although considerable effort has been expended trying to identify the source of the problem, no single solution has been agreed upon. The current study explored a new hypothesis, that developmental dyslexia may be due to faulty perceptual organization of linguistically relevant sensory input. To test that idea, sentence-length speech signals were processed to create either sine-wave or noise-vocoded analogs. Seventy children between 8 and 11 years of age, with and without dyslexia participated. Children with dyslexia were selected to have phonological awareness deficits, although those without such deficits were retained in the study. The processed sentences were presented for recognition, and measures of reading, phonological awareness, and expressive vocabulary were collected. Results showed that children with dyslexia, regardless of phonological subtype, had poorer recognition scores than children without dyslexia for both kinds of degraded sentences. Older children with dyslexia recognized the sine-wave sentences better than younger children with dyslexia, but no such effect of age was found for the vocoded materials. Recognition scores were used as predictor variables in regression analyses with reading, phonological awareness, and vocabulary measures used as dependent variables. Scores for both sorts of sentence materials were strong predictors of performance on all three dependent measures when all children were included, but only performance for the sine-wave materials explained significant proportions of variance when only children with dyslexia were included. Finally, matching young, typical readers with older children with dyslexia on reading abilities did not mitigate the group difference in recognition of vocoded sentences. Conclusions were that children with dyslexia have difficulty organizing linguistically relevant sensory input, but learn to do so for the structure preserved by sine-wave signals before they do so for other sorts of signal structure. These perceptual organization deficits could account for difficulties acquiring refined linguistic representations, including those of a phonological nature, although ramifications are different across affected children., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

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 /b/-/w/ 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.

Earlier work using sine-wave and noise-vocoded signals suggests that dynamic spectral structure plays a greater role in speech recognition for children than adults [Nittrouer and Lowenstein. (2010). J. Acoust. Soc. Am. 127, 1624-1635], but questions arise concerning whether outcomes can be compared because sine waves and wide noise bands are different in nature. The current study addressed that question using narrow noise bands for both signals, and applying a difference ratio to index the contribution made by dynamic spectral structure. Results replicated earlier findings, supporting the idea that dynamic spectral structure plays a critical role in speech recognition, especially for children.

Purpose: Children with speech sound disorder (SSD) and reading disability (RD) have poor phonological awareness, a problem believed to arise largely from deficits in processing the sensory information in speech, specifically individual acoustic cues. However, such cues are details of acoustic structure. Recent theories suggest that listeners also need to be able to integrate those details to perceive linguistically relevant form. This study examined abilities of children with SSD, RD, and SSD+RD not only to process acoustic cues but also to recover linguistically relevant form from the speech signal., Method: Ten- to 11-year-olds with SSD (n=17), RD (n=16), SSD+RD (n=17), and Controls (n=16) were tested to examine their sensitivity to (1) voice onset times (VOT); (2) spectral structure in fricative-vowel syllables; and (3) vocoded sentences., Results: Children in all groups performed similarly with VOT stimuli, but children with disorders showed delays on other tasks, although the specifics of their performance varied., Conclusion: Children with poor phonemic awareness not only lack sensitivity to acoustic details, but are also less able to recover linguistically relevant forms. This is contrary to one of the main current theories of the relation between spoken and written language development., Learning Outcomes: Readers will be able to (1) understand the role speech perception plays in phonological awareness, (2) distinguish between segmental and global structure analysis of speech perception, (3) describe differences and similarities in speech perception among children with speech sound disorder and/or reading disability, and (4) recognize the importance of broadening clinical interventions to focus on recognizing structure at all levels of speech analysis., (Copyright © 2011 Elsevier Inc. All rights reserved.)

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., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The ability to recognize speech involves sensory, perceptual, and cognitive processes. For much of the history of speech perception research, investigators have focused on the first and third of these, asking how much and what kinds of sensory information are used by normal and impaired listeners, as well as how effective amounts of that information are altered by "top-down" cognitive processes. This experiment focused on perceptual processes, asking what accounts for how the sensory information in the speech signal gets organized. Two types of speech signals processed to remove properties that could be considered traditional acoustic cues (amplitude envelopes and sine wave replicas) were presented to 100 listeners in five groups: native English-speaking (L1) adults, 7-, 5-, and 3-year-olds, and native Mandarin-speaking adults who were excellent second-language (L2) users of English. The L2 adults performed more poorly than L1 adults with both kinds of signals. Children performed more poorly than L1 adults but showed disproportionately better performance for the sine waves than for the amplitude envelopes compared to both groups of adults. Sentence context had similar effects across groups, so variability in recognition was attributed to differences in perceptual organization of the sensory information, presumed to arise from native language experience.

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.

When labeling syllable-initial fricatives, children have been found to weight formant transitions more and fricative-noise spectra less than adults, prompting the suggestion that children attend more to the slow vocal-tract movements that create syllabic structure than to the rapid gestures more closely aligned with individual phonetic segments. That explanation fits well with linguistic theories, but an alternative explanation emerges from auditory science: Perhaps children attend to formant transitions because they are found in voiced signal portions, and so formants share a common harmonic structure. This work tested that hypothesis by using two kinds of stimuli lacking harmonicity: sine-wave and whispered speech. Adults and children under 7 years of age were asked to label fricative-vowel syllables in each of those conditions, as well as natural speech. Results showed that children did not change their weighting strategies from those used with natural speech when listening to sine-wave stimuli, but weighted formant transitions less when listening to whispered stimuli. These findings showed that it is not the harmonicity principle that explains children's preference for formant transitions in phonetic decisions. It is further suggested that children are unable to recover formant structure when those formants are not spectrally prominent and/or are noisy.

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.

Cochlear implants allow many individuals with profound hearing loss to understand spoken language, even though the impoverished signals provided by these devices poorly preserve acoustic attributes long believed to support recovery of phonetic structure. Consequently, questions may be raised regarding whether traditional psycholinguistic theories rely too heavily on phonetic segments to explain linguistic processing while ignoring potential roles of other forms of acoustic structure. This study tested that possibility. Adults and children (8 years old) performed two tasks: one involving explicit segmentation, phonemic awareness, and one involving a linguistic task thought to operate more efficiently with well-defined phonetic segments, short-term memory. Stimuli were unprocessed (UP) signals, amplitude envelopes (AE) analogous to implant signals, and unprocessed signals in noise (NOI) that provided a degraded signal for comparison. Adults’ results for short-term recall were similar for UP and NOI, but worse for AE stimuli. The phonemic awareness task revealed the opposite pattern across AE and NOI. Children's results for short-term recall showed similar decrements in performance for AE and NOI compared to UP, even though only NOI stimuli showed diminished results for segmentation. Conclusions were that perhaps traditional accounts are too focused on phonetic segments, something implant designers and clinicians need to consider. [ABSTRACT FROM PUBLISHER]

Traditional accounts of speech perception generally hold that listeners use isolable acoustic “cues” to label phonemes. For syllable-final stops, duration of the preceding vocalic portion and formant transitions at syllable’s end have been considered the primary cues to voicing decisions. The current experiment tried to extend traditional accounts by asking two questions concerning voicing decisions by adults and children: (1) What weight is given to vocalic duration versus spectral structure, both at syllable’s end and across the syllable? (2) Does the naturalness of stimuli affect labeling? Adults and children (4, 6, and 8 years old) labeled synthetic stimuli that varied in vocalic duration and spectral structure, either at syllable’s end or earlier in the syllable. Results showed that all listeners weighted dynamic spectral structure, both at syllable’s end and earlier in the syllable, more than vocalic duration, and listeners performed with these synthetic stimuli as listeners had performed previously with natural stimuli. The conclusion for accounts of human speech perception is that rather than simply gathering acoustic cues and summing them to derive strings of phonemic segments, listeners are able to attend to global spectral structure, and use it to help recover explicitly phonetic structure. [ABSTRACT FROM AUTHOR]