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Purpose to investigate prosodic boundary effects on the comprehension of attachment ambiguities in Brazilian Portuguese and to test two hypotheses relying on the notion of boundary strength: the absolute boundary hypothesis (ABH) and the relative boundary hypothesis (RBH). Manipulations of prosodic structure influence how listeners interpret syntactically ambiguous sentences. However, the role of prosody in spoken language comprehension of sentences has received limited attention in languages other than English, particularly from a developmental perspective. Methods Twenty-three adults and 15 children participated in a computerized sentence comprehension task involving syntactically ambiguous sentences. Each sentence was recorded in eight different prosodic forms with acoustic manipulations of F0, duration and pause varying the boundary size to reflect predictions of the ABH and RBH. Results Children and adults differed in how prosody influenced their syntactic processing and children were significantly slower than adults. Results indicated that interpretation of sentences varied according to their prosodic forms. Conclusion Neither the ABH or the RBH explained how children and adults who speak Brazilian Portuguese use prosodic boundaries to disambiguate sentences. There is evidence that the way prosodic boundaries influence disambiguation varies cross-linguistically. RESUMO Objetivo investigar os efeitos de fronteiras prosódicas na compreensão de ambiguidades sintáticas no português brasileiro além de testar duas hipóteses baseadas na noção de intensidade de fronteira: a hipótese de fronteira absoluta (ABH) e a hipótese de fronteira relativa (RBH). Manipulações da estrutura prosódica influenciam como os ouvintes interpretam frases sintaticamente ambíguas. No entanto, o papel da prosódia na compreensão da linguagem oral tem recebido atenção limitada em línguas além do inglês, particularmente do ponto de vista do desenvolvimento. Método Vinte e três adultos e 15 crianças participaram de uma tarefa computadorizada de compreensão de frases envolvendo frases sintaticamente ambíguas. Cada frase foi gravada em oito formas prosódicas diferentes com manipulações acústicas de F0, duração, e pausa, variando o tamanho da fronteira prosódica de modo a transparecer as previsões da ABH e RBH. Resultados Crianças e adultos diferiram em como a prosódia influenciou o processamento sintático; as crianças foram significativamente mais lentas que os adultos. Os resultados indicaram que a interpretação das frases variou de acordo com suas formas prosódicas. Conclusão Nenhuma das hipóteses (ABH ou RBH) explica como crianças e adultos falantes do Português brasileiro utilizam as fronteiras prosódicas para desambiguar frases. Há evidências de que a maneira com a qual os limites prosódicos influenciam a desambiguação de frases varia entre os idiomas.

The present study investigated the comprehension of subject and objectGrowth Curve Analysis (GCA) was used to compare eye gaze fixations and gaze patterns to the appropriate subject or object nouns within a four-picture array between 16 children with CI and 31 children with typical hearing (aged 7;0-12;0) on wh-questions with and without added adjectives to increase length. Offline accuracy was also compared.Findings indicated children with typical hearing exhibited more fixations to the target noun across all conditions, supporting higher comprehension accuracy. Both groups of children demonstrated more fixations to the target noun in object questions and questions without added length. Patterns of eye movement were significantly different between groups, suggesting different patterns of eye gaze across the array before fixation on the target noun. Children with CI exhibited fewer fixations, slower speed to fixation, and differences in gaze patterns that may imply the presence of processing limitations. Error analyses also suggested that children with CI frequently fixated on a picture similar to the target noun.Results indicate children with CI comprehend questions more slowly than their hearing peers, which may be related to limitations in working memory.

Purpose This study investigated the auditory comprehension of Japanese sentences including relative clauses (RCs) by 52 Japanese-speaking children with typical development (TD) and 16 children with specific language impairment (SLI). Method A picture-pointing task measured RC and main clause (MC) comprehension for object and subject relatives in sentences with varying lengths. The accuracy of RC only, MC only, and combined comprehension (RC and MC) was analyzed with linear mixed-effects (logistic) models to examine accuracy and the effects of the deep gap–filler distance (structural complexity), the surface linear distance, and sentence length for the two participant groups. Six language tests and two working memory tests were administered to determine language and working memory status. A factor analysis grouped them into two factors that were examined as predictors of comprehension performance. Results Initial models indicated that children with SLI performed more poorly than their peers with TD. Working memory abilities predicted the comprehension of subject and object relative sentences, but language abilities other than a general measure of sentence comprehension were only limited predictors. In a series of pairwise comparisons, children with SLI did not exhibit comprehension facilitation for RC sentences with lower structural complexity, nor did they exhibit comprehension facilitation when the linear distance between the gap and the filler was shorter, perhaps because of their overall lower performance. Children with TD made more errors on sentences with higher structural complexity but did not exhibit any linear distance effects. Neither group exhibited effects of noun phrase or sentence length. Conclusions Japanese-speaking children with TD exhibited negative comprehension effects of increased deep structure complexity, but not of linear surface distance or sentence noun phrase length. The children with SLI face challenges in comprehending both subject and object relative sentences compared to their typically developing peers. Their poorer working memory abilities are the primary factor that constrains their performance.

Purpose Previous studies with children and adults have demonstrated a familiar talker advantage —better word recognition for familiar talkers. The goal of the current study was to test whether this phenomenon is modulated by a child's language ability. Method Sixty children with a range of language ability were trained to learn the voices of 3 foreign-accented, German–English bilingual talkers and received feedback about their performance. Both before and after this talker voice training, children completed a spoken word recognition task in which they heard consonant–vowel–consonant words mixed with noise that were spoken by the 3 familiarized talkers and by 3 unfamiliar German–English bilinguals. Results Two findings emerged from this study: First, children with both higher and lower language ability performed similarly on the familiarized talkers. Second, children with higher language scores performed similarly on both the familiarized and unfamiliar talkers, whereas children with lower language scores performed worse on the unfamiliar talkers compared to familiar talkers, suggesting an inability to generalize to novel, unfamiliar talkers who spoke with a similar accent. Discussion Together, these findings indicate that children with higher language scores are able to generalize knowledge about foreign-accented talkers to help spoken word recognition for novel talkers with the same accent. In contrast, children with lower language skills did not exhibit the same magnitude of generalization. This lack of generalization to similar talkers may mean that children with lower language skills are at a disadvantage in spoken language tasks because they are unable to process speech as well when listening to unfamiliar talkers.

Several aspects of early language skills, including parent-report measures of vocabulary, phoneme discrimination, speech segmentation, and speed of lexical access predict later childhood language outcomes. To date, no studies have examined the long-term predictive validity of novel word learning. We examined whether individual differences in novel word learning at 21 months predict later childhood receptive vocabulary outcomes rather than generalized cognitive abilities. Twenty-eight 21-month-olds were taught novel words using a modified version of the Intermodal Preferential Looking Paradigm. Seventeen children (range 7–10 years) returned to participate in a longitudinal follow-up. Novel word learning in infancy uniquely accounted for 22% of the variance in childhood receptive vocabulary but did not predict later childhood visuospatial ability or non-verbal IQ. These results suggest that the ability to associate novel sound patterns to novel objects, an index of the process of word learning, may be especially important for long-term language mastery.

This study examined the linguistic and individual-level factors that render case marking a vulnerable domain in English-dominant Greek heritage children. We also investigated whether heritage language (HL) children can use case-marking cues to interpret (non-)canonical sentences in Greek similarly to their monolingual peers. A group of six- to twelve-year-old Greek heritage children in New York City and a control group of age-matched monolingual children living in Greece participated in a production and a picture verification task targeting case marking and (non-)canonical word order in Greek. HL children produced syncretic inflectional errors, also found in preschool monolingual children. In the comprehension task, HL children showed variable performance on the non-canonical OVS but ceiling performance on the SVO conditions, which suggests influence from English. Linguistic factors such as case transparency affected comprehension, whereas child-level factors such as proficiency and degree of (early) use of Greek influenced performance on both modalities.

Purpose This sentence processing experiment examined the abilities of children with specific language impairment (SLI) and children with typical language development (TD) to establish relations between pronouns or reflexives and their antecedents in real time. Method Twenty-two children with SLI and 24 age-matched children with TD (7;3–10;11 [years;months]) participated in a cross-modal picture priming experiment to determine whether they selectively activated the correct referent at the pronoun or reflexive in sentences. Triplets of auditory sentences, identical except for the presence of a pronoun, a reflexive, or a noun phrase along with a picture probe were used. Results The children with TD were slightly more accurate in their animacy judgments of pictures, but the groups exhibited the same reaction time (RT) pattern. Both groups were slower for sentences with pronouns than with reflexives or noun phrases. The children with SLI had longer RTs than their peers with TD. Conclusions Children with SLI activated only the appropriate antecedent at the pronoun or reflexive, reflecting intact core knowledge of binding as was true for their TD peers. The overall slower RT for children with SLI suggests that any deficit may be the result of processing deficits, perhaps attributable to interference effects.

Comprehension of predicates and reflexives was examined in children who stutter (CWS) and children who do not stutter (CWNS) who were between 9 years, 7 months and 10 years, 2 months. Demands on working memory and manual reaction time were also assessed in two experiments that employed a four-choice picture-selection sentence comprehension task. CWS were less accurate than CWNS on the attachment of predicates. For reflexives, there was no between-group difference in accuracy, but there was a difference in speed. The two constructions induced processing at different points on a speed–accuracy continuum with CWS sacrificing accuracy to respond fast with predicates, while they maintained accuracy of reflexives by responding slower relative to CWNS. Predicates made more demands on language than nonspeech motor reaction time, whereas the reverse was the case with reflexives for CWS compared to CWNS.

Background: Frequency discrimination is often impaired in children developing language atypically. However, findings in the detection of small frequency changes in these children are conflicting. Previous studies on children’s auditory perceptual abilities usually involved establishing differential sensitivity thresholds in sample populations who were not tested for auditory deficits. To date, there are no data comparing suprathreshold frequency discrimination ability in children tested for both auditory processing and language skills. Purpose: : This study examined the perception of small frequency differences (Δf) in children with auditory processing disorder (APD) and/or specific language impairment (SLI). The aim was to determine whether children with APD and children with SLI showed differences in their behavioral responses to frequency changes. Results were expected to identify different degrees of impairment and shed some light on the auditory perceptual overlap between pediatric APD and SLI. Research Design: An experimental group design using a two-alternative forced-choice procedure was used to determine frequency discrimination ability for three magnitudes of Δf from the 1000-Hz base frequency. Study Sample: Thirty children between 10 years of age and 12 years, 11 months of age: 17 children with APD and/or SLI, and 13 typically developing (TD) peers participated. The clinical groups included four children with APD only, four children with SLI only, and nine children with both APD and SLI. Data Collection and Analysis: Behavioral data collected using headphone delivery were analyzed using the sensitivity index d′, calculated for three Δf was 2%, 5%, and 15% of the base frequency or 20, 50, and 150 Hz. Correlations between the dependent variable d′ and the independent variables measuring auditory processing and language skills were also obtained. A stepwise regression analysis was then performed. Results: TD children and children with APD and/or SLI differed in the detection of small-tone Δf. In addition, APD or SLI status affected behavioral results differently. Comparisons between auditory processing test scores or language test scores and the sensitivity index d′ showed different strengths of correlation based on the magnitudes of the Δf. Auditory processing scores showed stronger correlation to the sensitivity index d′ for the small Δf, while language scores showed stronger correlation to the sensitivity index d′ for the large Δf. Conclusion: Although children with APD and/or SLI have difficulty with behavioral frequency discrimination, this difficulty may stem from two different levels: a basic auditory level for children with APD and a higher language processing level for children with SLI; the frequency discrimination performance seemed to be affected by the labeling demands of the same versus different frequency discrimination task for the children with SLI.

Purpose In the present study, the authors examined lexical naming in children with cochlear implants (CIs). The goal was to determine whether children with CIs have deficits in lexical access and organization as revealed through reaction time in picture-naming and verbal fluency (VF) experiments. Method Children with CIs ( n = 20, ages 7–10) were compared with 20 children with normal hearing (NH) matched for age and nonverbal IQ. Lexical abilities were examined using two naming tasks: a timed picture-naming task and a phonological and semantic VF naming task. Picture naming taps into lexical access capabilities and the VF task elucidates lexical organization. Results No group differences were found between children with CIs and children with NH on the timed picture-naming task. Children with CIs generated significantly fewer words than the children with NH on the VF tasks. Larger group differences were found for the phonological VF task compared with the semantic VF task. Conclusions Limited early linguistic and auditory experiences may affect lexical representations and organization (lexical-semantic connections) in school-age children with hearing loss who use CIs. Further analyses and studies should continue to examine these underlying linguistic deficits. The present results suggest a need to emphasize not only increasing the size of children's vocabularies during therapy, but also expanding and increasing the semantic and phonological richness of their lexical representations.

This study examined the influence of phonotactic probability on word recognition in English-speaking toddlers. Typically developing toddlers completed a preferential looking paradigm using familiar words, which consisted of either high or low phonotactic probability sound sequences. The participants’ looking behavior was recorded in response to correctly-produced and incorrectly-produced forms of familiar words. Results indicate that toddlers were more sensitive to mispronunciations of high probability words as compared to low probability words. Toddlers’ word recognition skills were more closely related to the frequency with which they have heard and produced phonological sequences, rather than word familiarity. These findings are discussed in terms of toddlers with expressive language delay.

Using an identification task, we examined lexical effects on the perception of vowel duration as a cue to final consonant voicing in 12 children with specific language impairment (SLI) and 13 age-matched (6;6-9;6) peers with typical language development (TLD). Naturally recorded CV/t/sets [word-word (WW), nonword-nonword (NN), word-nonword (WN) and nonword-word (NW)] were edited to create four 12-step continua. Both groups used duration as an identification cue but it was a weaker cue for children with SLI. For NN, WN and NW continua, children with SLI demonstrated certainty at shorter vowel durations than their TLD peers. Except for the WN continuum, children with SLI demonstrated category boundaries at shorter vowel durations. Both groups exhibited lexical effects, but they were stronger in the SLI group. Performance on the WW continuum indicated adequate perception of fine-grained duration differences. Strong lexical effects indicated reliance on familiar words in speech perception.

Background Children with specific language impairment (SLI) show particular difficulty comprehending and producing object (Who did the bear follow?) relative to subject (Who followed the tiger?) wh-questions. Aims To determine if school-age children with SLI, relative to children with typical development (TD), show a more distinct unevenness, or asymmetry, in the comprehension of these questions. In addition, this study examined whether the sustained left-anterior negativity (LAN) in event-related potentials (ERP) could be used as a marker for atypical processing of these questions in children with SLI. The LAN effect signals the greater working memory processes for maintaining in memory the dislocated object in object wh-questions and reflects working memory capacity in adults. It was predicted that the amplitude of the LAN would be greater in children with SLI, reflecting the characteristic low working memory capacity in this population. The concomitance of these behavioural and electrophysiological effects would suggest that the subject–object asymmetry in SLI should be investigated in relation to poor working memory skills. Methods & Procedures Groups including 13 children with SLI, 17 same-age TD children and 18 normal adults completed an auditory sentence comprehension task requiring button responses while continuous electroencephalography (EEG) was collected. Accuracy for subject and object questions was calculated. The mean amplitude values of the ERP data for the wh-questions were examined to identify differential processing of subject and object questions. Outcomes & Results TD children demonstrated asymmetrical comprehension of subject and object wh-questions, whereas children with SLI comprehended both question types poorly and adults did not show subject–object asymmetry. ERP waveforms spanning the wh-dependency revealed a large and widespread sustained anterior positivity for object relative to subject questions in the TD group, indicating differential processing of these questions. This effect was attenuated and non-significant in the SLI group. The adults’ grand average waveforms showed the expected LAN effect, which was opposite in polarity relative to the children, although it only approached significance. Conclusions & Implications The finding of less differential processing of subject and object wh-questions in SLI relative to TD children suggests inefficient maintenance of sentential information in working memory for object questions in SLI. Whereas behavioural methods did not identify subject–object asymmetry in SLI, the more fine-grained method of ERPs elucidated this effect. Further analysis of working memory as the basis for the subject–object asymmetry in SLI is critical for identifying appropriate intervention targets for this population.

In this plenary paper we present a review of language research in children with cochlear implants along with at outline of a five-year project designed to examine lexical access for production and recognition. The project will use auditory priming, picture naming with auditory or visual interfering stimuli (Picture-Word Interference and Picture-Picture Interference, respectively) and eye tracking paradigms to examine the role of semantic and various phonological factors. Preliminary data are presented from auditory priming, the picture-word interference, and picture-picture interference tasks. The emergence of group difference is briefly discussed.

Traditional linguistics described inventories of sounds, words, and sentences observed in a language. Morphology is the branch of linguistics concerned with the smallest meaningful units of language including words, which are free-standing morphemes, as well as inflectional affixes and derivational affixes, which are bound morphemes. Pragmatic deficits occur across populations of children with language disorders. Syntax examines the formation of sentences across languages, defining the workings of the Computational System. Pragmatics is concerned with language usage in context and the contribution of context to meaning. Semantics is concerned with meaning in language at various levels including words, phrases, sentence, or discourse. Phonology is concerned with the sounds of language and the knowledge that underlies their systematic occurrence. The notion of critical period is rejected because of a lack of compelling evidence, and in light of evidence that under non-clinical circumstances languages can be learned across the lifespan, given adequate input.

Roger Brown considered how children come to attach a word to things and categories of things in the world. Attaching words or names to things and categories is basic to human language—the label Specific Language Impairment(SLI) is one example. Children with SLI have deficits in working memory that may underlie their language deficits. Children with phonological disorders are routinely excluded from studies of SLI in order to avoid including children whose speech production limitations might be the result of apparent nonlinguistic limitations in language production. Pragmatics is a heterogeneous category of language abilities including presuppositions about the knowledge and social status of the listener, the communicative intent or function of utterances, the structure of narratives and discourse and conversation, as well as the more global use of language and nonlinguistic means of communication. Children with SLI also have deficits in conversation that may reflect either social deficits or structural language deficits.

PurposeThis study investigated prosodic boundary effects on the comprehension of attachment ambiguities in children with cochlear implants (CIs) and normal hearing (NH) and tested the absolute boundary hypothesis and the relative boundary hypothesis. Processing speed was also investigated.MethodFifteen children with NH and 13 children with CIs (ages 8–12 years) who are monolingual speakers of Brazilian Portuguese participated in a computerized comprehension task with sentences containing prepositional phrase attachment ambiguity and manipulations of prosodic boundaries.ResultsChildren with NH and children with CIs differed in how they used prosodic forms to disambiguate sentences. Children in both groups provided responses consistent with half of the predictions of the relative boundary hypothesis. The absolute boundary hypothesis did not characterize the syntactic disambiguation of children with CIs. Processing speed was similar in both groups.ConclusionsChildren with CIs do not use prosodic information to disambiguate sentences or to facilitate comprehension of unambiguous sentences similarly to children with NH. The results suggest that cross-linguistic differences may interact with syntactic disambiguation. Prosodic contrasts that affect sentence comprehension need to be addressed directly in intervention with children with CIs.

Background Toddlers who are late talkers demonstrate delays in phonological and lexical skills. However, the influence of phonological factors on lexical acquisition in toddlers who are late talkers has not been examined directly. Aims To examine the influence of phonotactic probability/neighbourhood density on word learning in toddlers who were late talkers using comprehension, production and word recognition tasks. Methods & Procedures Two-year-olds who were late talkers (n = 12) and typically developing toddlers (n = 12) were exposed to 12 novel pseudo-words for unfamiliar objects in ten training sessions. Pseudo-words contained high or low phonotactic probability English sound sequences. The toddlers’ comprehension, speech production and detection of mispronunciation of the newly learned words were examined using a preferential looking paradigm. Outcomes & Results Late talkers showed poorer performance than toddlers with typical language development in all three tasks: comprehension, production and detection of mispronunciations. The toddlers with typical language development showed better speech production and more sensitivity to mispronunciations for high than low phonotactic probability/neighbourhood density sequences. Phonotactic probability/neighbourhood density did not influence the late talkers’ speech production or sensitivity to mispronunciations; they performed similarly for pseudo-words with high and low phonotactic probability/neighbourhood density sound sequences. Conclusions & Implications The results indicate that some late talkers do not recognize statistical properties of their language, which may contribute to their slower lexical learning.

Purpose In this study, the authors examined the comprehension of sentences with predicates and reflexives that are linked to a nonadjacent noun as a test of the hierarchical ordering deficit (HOD) hypothesis. That hypothesis and more modern versions posit that children with specific language impairment (SLI) have difficulty in establishing nonadjacent (hierarchical) relations among elements of a sentence. The authors also tested whether additional working memory demands in constructions containing reflexives affected the extent to which children with SLI incorrectly structure sentences as indicated by their picture-pointing comprehension responses. Method Sixteen Brazilian Portuguese-speaking children (8;4–10;6 [years;months]) with SLI and 16 children with typical language development (TLD) matched for age (±3 months), gender, and socioeconomic status participated in 2 experiments (predicate and reflexive interpretation). In the reflexive experiment, the authors also manipulated working memory demands. Each experiment involved a 4-choice picture selection sentence comprehension task. Results Children with SLI were significantly less accurate on all conditions. Both groups made more hierarchical syntactic construction errors in the long working memory condition than in the short working memory condition. Conclusion The HOD hypothesis was not confirmed. For both groups, syntactic factors (structural assignment) were more vulnerable than lexical factors (prepositions) to working memory effects in sentence miscomprehension.

This paper examined neurophysiological correlates of speech in children with language impairment (LI) and typical language development (TLD) across four experiments using different speech stimuli and tasks.The T-complex event-related potential (ERP) components and other ERP components (e.g., mismatch negativity [MMN]; N400) were examined. A subset of the children participated in more than one of the experiments.73% of the children with LI had poor T-complex measures compared to only 13% of children with TLD. The T-complex measures were more comparable, in terms of indicating typical versus deviant processing, to neurophysiological measures of language processing, such as lexical discrimination, than to other measures of auditory and speech processing, such as the MMN. Only one LI child showed no poor measures and 64% showed three or more poor neurophysiological measures. However, 50% of children with TLD showed no poor neurophysiological measures, and 82% of the TLD children showed no more than two poor measures.These results suggest that poor auditory processing, as measured by the T-complex, is a marker for LI and that multiple deficits serve to mark LI.The T-complex measures, indexing secondary auditory cortex, reflect an important aspect of processing in speech and language development.

Purpose The purpose of this study was to contribute to the current understanding of how children with specific language impairment (SLI) organize their mental lexicons. The study examined semantic and phonological priming in children with and without SLI. Method Thirteen children (7;0–11;3 [years;months]) with SLI and 13 age-matched children with typical language development participated in this study. Prime–target pairs (semantic, phonological, and repetition) were embedded within a running list of words so that the actual pairs were imperceptible. Reaction times to an animacy judgment (alive vs. not alive) were analyzed. The experiment featured 500-ms and 1,000-ms interstimulus intervals (ISIs) between primes and targets. Results Children with SLI exhibited priming effects in the repetition condition at both ISIs; however, phonological and semantic effects were absent. Typically developing children exhibited effects in the repetition at both ISIs. Semantic and phonological effects were absent at 500 ms ISIs, but present at 1,000 ms ISIs. Conclusions Although children with SLI have priming mechanisms similar to those of their age-matched peers, the absence of semantic and phonological priming suggests that these connections are not strong enough by themselves to yield priming effects. These findings are discussed in the context of semantic and phonological priming, representation, and generalized slowing.

Purpose The authors investigated the neurophysiological bases of vowel perception in children with specific language impairment (SLI) compared with typical language development (TLD) controls using 250-ms phonetically similar vowels. In a previous study, children with SLI showed a poor neurophysiological response (the mismatch negativity [MMN]) to 50-ms versions of these vowels, regardless of whether attention was directed to (attend) or away (passive) from the auditory modality (V. Shafer, M. Morr, H. Datta, D. Kurtzberg, & R. Schwartz, 2005). They hypothesized that longer vowels would allow for improved speech perception. Method Brain responses were elicited to the vowel contrast in 2 conditions: (a) attend and (b) passive. Behavioral discrimination and identification responses were also examined. Results Both SLI and TLD groups showed evidence of discrimination (MMN) of the vowels in the attend and passive conditions. Only subtle differences in the scalp topography of a late negative (LN) brain component were observed between groups. The SLI compared with the TLD group showed significantly poorer identification of these long vowels, as found previously with the shorter vowels. Conclusions Increased vowel duration can improve discrimination in children with SLI. However, poor identification of these longer vowels by some children with SLI suggests a deficit in long-term phonological representations or accessing these representations.

The Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system–PV modules for portable applications that operate at greater than 50% efficiency. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space. Our approach is driven by proven quantitative models for the solar cell design, the optical design, and the integration of these designs. Optical systems efficiency with an optical efficiency of 93% and solar cell device results under ideal dichroic splitting optics summing to 42·7 ± 2·5% are described. Copyright © 2008 John Wiley & Sons, Ltd.

Two experiments examined the time course of lexical information availability in 20 adults, 20 children (8;0-10;0) with typical language development, and in 20 children (8;0-10;0) with specific language impairment. A cross-modal picture-word interference paradigm was used in which participants named the pictures as quickly as possible while ignoring the phonologically and semantically related interfering words. A novel early phonological interference effect appeared in all groups. Similar temporal patterns were revealed for the adults and the typical language development group, supporting the notion of similar underlying lexicalization mechanisms. Parametric differences were found in overall response times and errors, with children responding slower and producing more errors than adults. The presence of a phonological facilitation effect suggests that children with specific language impairment utilize phonological primes to ease lexical access. Children with specific language impairment exhibited lingering semantic inhibition and a late semantic inhibition effect suggesting difficulty in processing semantic information. Data from all participants support the cascaded processing model of lexical access.

This study examines electrocortical activity associated with visual and auditory sensory perception and lexical-semantic processing in nonverbal (NV) or minimally-verbal (MV) children with Autism Spectrum Disorder (ASD). Currently, there is no agreement on whether these children comprehend incoming linguistic information and whether their perception is comparable to that of typically developing children. Event-related potentials (ERPs) of 10 NV/MV children with ASD and 10 neurotypical children were recorded during a picture-word matching paradigm. Atypical ERP responses were evident at all levels of processing in children with ASD. Basic perceptual processing was delayed in both visual and auditory domains but overall was similar in amplitude to typically-developing children. However, significant differences between groups were found at the lexical-semantic level, suggesting more atypical higher-order processes. The results suggest that although basic perception is relatively preserved in NV/MV children with ASD, higher levels of processing, including lexical- semantic functions, are impaired. The use of passive ERP paradigms that do not require active participant response shows significant potential for assessment of non-compliant populations such as NV/MV children with ASD.

Purpose The present study examined whether engaging working memory in a secondary task benefits speech fluency. Effects of dual-task conditions on speech fluency, rate, and errors were examined with respect to predictions derived from three related theoretical accounts of disfluencies. Method Nineteen adults who stutter and twenty adults who do not stutter participated in the study. All participants completed 2 baseline tasks: a continuous-speaking task and a working-memory (WM) task involving manipulations of domain, load, and interstimulus interval. In the dual-task portion of the experiment, participants simultaneously performed the speaking task with each unique combination of WM conditions. Results All speakers showed similar fluency benefits and decrements in WM accuracy as a result of dual-task conditions. Fluency effects were specific to atypical forms of disfluency and were comparable across WM-task manipulations. Changes in fluency were accompanied by reductions in speaking rate but not by corresponding changes in overt errors. Conclusions Findings suggest that WM contributes to disfluencies regardless of stuttering status and that engaging WM resources while speaking enhances fluency. Further research is needed to verify the cognitive mechanism involved in this effect and to determine how these findings can best inform clinical intervention. Supplemental Material https://doi.org/10.23641/asha.14963808

English-speaking children with specific language impairment (SLI) perform more poorly than their typically developing peers in verbal working memory tasks where processing and storage are simultaneously required. Hungarian is a language with a relatively free word order and a rich agglutinative morphology.To examine the effect of linguistic structure on working memory performance. It was examined whether syntactic complexity has a larger impact on working memory performance than sentence length in Hungarian-speaking children, similar to the findings in English speaking children.In Experiment 1, performance accuracy was measured with two linguistic span tasks that included stimuli with varying sentence length and syntactic complexity. Experiment 2 examined the impact of sentence length and morphological complexity on working memory performance.Children with SLI performed more poorly than their age-matched peers in all working memory tasks. Their error patterns differed from those of children with typical language development. Children with SLI produced a high number of interference errors that indicate poor executive functions. The findings were compared with previous results of English-speaking children. Complexity affected working memory performance accuracy differently across languages. In English, it was the increase of syntactic complexity that resulted in a decrease in performance accuracy, whereas in Hungarian, it was the morphological complexity that had a large impact on working memory performance.Working memory performance depends on the linguistic characteristics of the language tested. In both English- and Hungarian-speaking children, complexity has a larger effect on verbal working memory performance than the length of the stimuli. However, complexity affects working memory performance accuracy differently across languages.

The present study investigated 3-year-old children's perception and production of Mandarin lexical tones in monosyllabic words. Thirteen 3-year-old, Mandarin-speaking children participated in the study. Tone perception was examined by a picture-pointing task, and tone production was investigated by picture naming. To compare children's productions with the adult forms, 4 mothers of the children were asked to say the same set of words to their children in a picture-reading activity. The children's and mothers' productions were low-pass filtered at 500 Hz and 400 Hz, respectively, to eliminate segmental information. Ten Mandarin-speaking judges identified the productions of tones from the filtered speech. Adult productions were more accurately identified than productions of the children. The children perceived the level, rising, and falling tones with relatively high accuracy. The dipping tone posed the greatest difficulty for the children in both perception and production.

In a first experiment, we recorded event-related-potentials (ERPs) to “the” followed by meaningful words (Story) versus “the” followed by nonsense syllables (Nonse). Left and right lateral anterior positivities (LAPs) were seen from the onset of “the” up to 200 ms in both conditions. Later than 200 ms following the onset of “the,” the left and right LAPs continued for “the” in the Story, but were replaced by a negativity in the Nonse Condition. In a second experiment, ERPs were recorded to “the” in the Story and Nonse contexts mixed together under two different task instructions (Attend to the auditory stimuli versus ignore the auditory stimuli). The same pattern of findings as Experiment 1 were observed for the Story and Nonse contexts when the participants attended to the auditory stimuli. Ignoring the auditory stimuli led to an attenuation of the right LAP, supporting the hypothesis that it is an index of discourse processing.

An eye-gaze and production probe examined the ability of 2-year-old children to perceive and produce minimal pairs of novel trisyllabic words with primary stress on the first or second syllables. The syllables contained dissimilar or similar vowel contrasts to determine if segments affected omission. The results supported a prosodic model, with the children's bias toward a strong-weak-weak prosodic structure and omission more frequent for the first syllable of the weak-strong-weak word pairs. Syllable omission was less frequent for strong-weak-weak word pairs that contained dissimilar vowels, suggesting that segments play a role in syllable omission.

This study examined the use of clitic pronouns by incipient bilingual Spanish-speaking 4- and 5-year-old children with and without language impairments. Incipient bilingualism refers to the initial stages of contact between two languages, when an individual still has only passive knowledge of a second language. The participants included 10 children with typical language development and 10 children with specific language impairment (SLI). The experimental task elicited clitic pronouns serving as direct objects with finite verbs (lo, la, los, and las). The children who had SLI used clitic pronouns less frequently than their age-matched peers and were less accurate in their use of gender agreement for clitics. No group differences were found for third person singular and plural verb inflections in the preterite tense. These results were compared to previous studies of Spanish- and Italian-speaking children with SLI.

Purpose Children with specific language impairment (SLI) appear to demonstrate deficits in attention and its control. Selective attention involves the cognitive control of attention directed toward a relevant stimulus and simultaneous inhibition of attention toward irrelevant stimuli. The current study examined attention control during a cross-modal word recognition task. Method Twenty participants with SLI (ages 9–12 years) and 20 age-matched peers with typical language development (TLD) listened to words through headphones and were instructed to attend to the words in 1 ear while ignoring the words in the other ear. They were simultaneously presented with pictures and asked to make a lexical decision about whether the pictures and auditory words were the same or different. Accuracy and reaction time were measured in 5 conditions, in which the stimulus in the unattended channel was manipulated. Results The groups performed with similar accuracy. Compared with their peers with TLD, children with SLI had slower reaction times overall and different within-group patterns of performance by condition. Conclusions Children with TLD showed efficient inhibitory control in conditions that required active suppression of competing stimuli. Participants with SLI had difficulty exerting control over their auditory attention in all conditions, with particular difficulty inhibiting distractors of all types.