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Purpose: We aimed to develop a noninvasive neural test of language comprehension to use with nonspeaking children for whom standard behavioral testing is unreliable (e.g., minimally verbal autism). Our aims were threefold. First, we sought to establish the sensitivity of two auditory paradigms to elicit neural responses in individual neurotypical children. Second, we aimed to validate the use of a portable and accessible electroencephalography (EEG) system, by comparing its recordings to those of a research-grade system. Third, in light of substantial interindividual variability in individuals' neural responses, we assessed whether multivariate decoding methods could improve sensitivity. Method: We tested the sensitivity of two child-friendly covert N400 paradigms. Thirty-one typically developing children listened to identical spoken words that were either strongly predicted by the preceding context or violated lexical-semantic expectations. Context was given by a cue word (Experiment 1) or sentence frame (Experiment 2), and participants either made an overall judgment on word relatedness or counted lexical-semantic violations. We measured EEG concurrently from a research-grade system, Neuroscan's SynAmps2, and an adapted gaming system, Emotiv's EPOC+. Results: We found substantial interindividual variability in the timing and topology of N400-like effects. For both paradigms and EEG systems, traditional N400 effects at the expected sensors and time points were statistically significant in around 50% of individuals. Using multivariate analyses, detection rate increased to 88% of individuals for the research-grade system in the sentences paradigm, illustrating the robustness of this method in the face of interindividual variations in topography. Conclusions: There was large interindividual variability in neural responses, suggesting interindividual variation in either the cognitive response to lexical--semantic violations and/or the neural substrate of that response. Around half of our neurotypical participants showed the expected N400 effect at the expected location and time points. A low-cost, accessible EEG system provided comparable data for univariate analysis but was not well suited to multivariate decoding. However, multivariate analyses with a research-grade EEG system increased our detection rate to 88% of individuals. This approach provides a strong foundation to establish a neural index of language comprehension in children with limited communication.

Prosody is crucial for language comprehension because it highlights underlying structures. This study explores whether prosody facilitates "memory recall" to the same extent in L1 and L2, and whether memory recall is poorer in L2 or whether language-specific differences can mitigate L2 processing difficulties. Nineteen Greek learners of English, and a monolingual English baseline, repeated three-digit chunks with and without prosodic cues in L1 and L2. Prosody was a major facilitator of memory recall only in L1 despite the high proficiency of learners. This indicates that L2 mastery of prosody perception is hard to attain, mirroring production studies. However, when prosodic boundary cues were absent, memory recall in L2 was comparable to L1. This demonstrates that language-specific differences can attenuate more general processing difficulties in L2. This study is the first to demonstrate differences in prosodic processing in L1 and L2 resulting in poorer memory recall in L2.

Purpose: We aimed to develop a noninvasive neural test of language comprehension to use with nonspeaking children for whom standard behavioral testing is unreliable (e.g., minimally verbal autism). Our aims were threefold. First, we sought to establish the sensitivity of two auditory paradigms to elicit neural responses in individual neurotypical children. Second, we aimed to validate the use of a portable and accessible electroencephalography (EEG) system, by comparing its recordings to those of a researchgrade system. Third, in light of substantial interindividual variability in individuals' neural responses, we assessed whether multivariate decoding methods could improve sensitivity. Method: We tested the sensitivity of two child-friendly covert N400 paradigms. Thirty-one typically developing children listened to identical spoken words that were either strongly predicted by the preceding context or violated lexicalsemantic expectations. Context was given by a cue word (Experiment 1) or sentence frame (Experiment 2), and participants either made an overall judgment on word relatedness or counted lexical-semantic violations. We measured EEG concurrently from a research-grade system, Neuroscan's SynAmps2, and an adapted gaming system, Emotiv's EPOC+. Results: We found substantial interindividual variability in the timing and topology of N400-like effects. For both paradigms and EEG systems, traditional N400 effects at the expected sensors and time points were statistically significant in around 50% of individuals. Using multivariate analyses, detection rate increased to 88% of individuals for the research-grade system in the sentences paradigm, illustrating the robustness of this method in the face of interindividual variations in topography. Conclusions: There was large interindividual variability in neural responses, suggesting interindividual variation in either the cognitive response to lexical-semantic violations and/or the neural substrate of that response. Around half of our neurotypical participants showed the expected N400 effect at the expected location and time points. A low-cost, accessible EEG system provided comparable data for univariate analysis but was not well suited to multivariate decoding. However, multivariate analyses with a researchgrade EEG system increased our detection rate to 88% of individuals. This approach provides a strong foundation to establish a neural index of language comprehension in children with limited communication. Supplemental Material: https://doi.org/10.23641/asha. 12606311, Language is a crucial part of everyday life and something we often take for granted. In cases where people cannot speak or reliably communicate, it can be difficult to assess [...]

To design and evaluate the effectiveness of a stimulus material in eliciting the N400 event related potential (ERP). A set of 700 semantically congruent and incongruent sentences was developed in accordance with current linguistic norms, and validated with an electroencephalography (EEG) study, in which the influence of age and gender on the N400 ERP magnitude was analysed. Forty-five normal-hearing subjects (19–57 years, 21 females) participated in the EEG study. The stimulus material used in the EEG study elicited a robust N400 ERP, with a morphology consistent with the literature. Results also showed no statistically significant effect of age or gender on the N400 magnitude. The material presented in this paper constitutes the largest complete stimulus set suitable for both auditory and text-based N400 experiments. This material may help facilitate the efficient implementation of future N400 ERP studies, as well as promote standardisation and consistency across studies. [ABSTRACT FROM AUTHOR]

Although previous research has indicated that five-year-olds can use acoustic cues to disambiguate compounds (N1 + N2) from lists (N1, N2) (e.g., 'ice-cream' vs. 'ice, cream') (Yoshida & Katz, 2004, 2006), their productions are not yet fully adult-like (Wells, Peppé & Goulandris, 2004). The goal of this study was to examine this issue in Australian English-speaking children, with a focus on their use of F0, word duration, and pauses. Twenty-four five-year-olds and 20 adults participated in an elicited production experiment. Like adults, children produced distinct F0 patterns for the two structures. They also used longer word durations and more pauses in lists compared to compounds, indicating the presence of a boundary in lists. However, unlike adults, they also inappropriately inserted more pauses within the compound, suggesting the presence of a boundary in compounds as well. The implications for understanding children's developing knowledge of how to map acoustic cues to prosodic structures are discussed. [ABSTRACT FROM AUTHOR]

Prosody is crucial for language comprehension because it highlights underlying structures. This study explores whether prosody facilitates memory recall to the same extent in L1 and L2, and whether memory recall is poorer in L2 or whether language-specific differences can mitigate L2 processing difficulties. Nineteen Greek learners of English, and a monolingual English baseline, repeated three-digit chunks with and without prosodic cues in L1 and L2. Prosody was a major facilitator of memory recall only in L1 despite the high proficiency of learners. This indicates that L2 mastery of prosody perception is hard to attain, mirroring production studies. However, when prosodic boundary cues were absent, memory recall in L2 was comparable to L1. This demonstrates that language-specific differences can attenuate more general processing difficulties in L2. This study is the first to demonstrate differences in prosodic processing in L1 and L2 resulting in poorer memory recall in L2. [ABSTRACT FROM AUTHOR]