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Intact phonological processing is crucial for successful literacy acquisition. While individuals with difficulties in reading and spelling (i.e., developmental dyslexia) are known to experience deficient phoneme discrimination (i.e., segmental phonology), findings concerning their prosodic processing (i.e., suprasegmental phonology) are controversial. Because there are no behavior-independent studies on the underlying neural correlates of prosodic processing in dyslexia, these controversial findings might be explained by different task demands. To provide an objective behavior-independent picture of segmental and suprasegmental phonological processing in impaired literacy acquisition, we investigated event-related brain potentials during passive listening in typically and poor-spelling German school children. For segmental phonology, we analyzed the Mismatch Negativity (MMN) during vowel length discrimination, capturing automatic auditory deviancy detection in repetitive contexts. For suprasegmental phonology, we analyzed the Closure Positive Shift (CPS) that automatically occurs in response to prosodic boundaries. Our results revealed spelling group differences for the MMN, but not for the CPS, indicating deficient segmental, but intact suprasegmental phonological processing in poor spellers. The present findings point towards a differential role of segmental and suprasegmental phonology in literacy disorders and call for interventions that invigorate impaired literacy by utilizing intact prosody in addition to training deficient phonemic awareness. [ABSTRACT FROM AUTHOR]

Language acquisition requires infants' ability to track dependencies between distant speech elements. Infants as young as 3 months have been shown to successfully identify such non-adjacent dependencies between syllables, and this ability has been related to the maturity of infants' pitch processing. The present study tested whether 8- to 10-month-old infants (N = 68) can also learn dependencies at smaller segmental levels and whether the relation between dependency and pitch processing extends to other auditory features. Infants heard either syllable sequences encoding an item-specific dependency between non-adjacent vowels or between consonants. These frequent standard sequences were interspersed with infrequent intensity deviants and dependency deviants, which violated the non-adjacent relationship. Both vowel and consonant groups showed electrophysiological evidence for detection of the intensity manipulation. However, evidence for dependency learning was only found for infants hearing the dependencies across vowels, not consonants, and only in a subgroup of infants who had an above-average language score in a behavioral test. In a correlation analysis, we found no relation between intensity and dependency processing. We conclude that item-specific, segment-based non-adjacent dependencies are not easily learned by infants and if so, vowels are more accessible to the task, but only to infants who display advanced language skills. [ABSTRACT FROM AUTHOR]

Infants rapidly advance in their speech perception, electrophysiologically reflected in the transition from an immature, positive-going to an adult-like, negative-going mismatch response (MMR) to auditory deviancy. Although the MMR is a common tool to study speech perception development, it is not yet completely understood how different speech contrasts affect the MMR's characteristics across development. Thus, a systematic longitudinal investigation of the MMR's maturation depending on speech contrast is necessary. We here longitudinally explored the maturation of the infant MMR to four critical speech contrasts: consonant , vowel , vowel-length , and pitch. MMRs were obtained when infants (n = 58) were 2, 6 and 10 months old. To evaluate the maturational trajectory of MMRs, we applied second-order latent growth curve models. Results showed positive-going MMR amplitudes to all speech contrasts across all assessment points that decreased over time towards an adult-like negativity. Notably, the developmental trajectories of speech contrasts differed, implying that infant speech perception matures with different rates and trajectories throughout the first year, depending on the studied auditory feature. Our results suggest that stimulus-dependent maturational trajectories need to be considered when drawing conclusions about infant speech perception development reflected by the infant MMR. • Understanding speech perception development requires longitudinal investigations. • The Mismatch Response (MMR) is valuable to study infants' speech perception. • We investigated the infant MMR longitudinally across three assessment points. • MMRs to different speech features became more mature during infants' first year. • Different MMR trajectories imply feature-dependent maturation of speech perception. [ABSTRACT FROM AUTHOR]

Abstract: Spoken language is hierarchically structured into prosodic units divided by prosodic breaks. The largest prosodic breaks in an utterance are intonational phrase boundaries (IPBs), which are defined by three acoustic cues, namely, pitch change, preboundary lengthening, and pausing. Previous studies have revealed that the electrophysiological marker of IPB perception, the Closure Positive Shift (CPS), is established between 2 and 3 years of age. Here, we examined the neural activity underlying IPB perception in children by targeting their reliance on pausing; hypothesized to be a key boundary cue in German. To evaluate the role of pausing, we tested IPB perception without the boundary pause, but with pitch change and preboundary lengthening. We tested children at the age of 3 years, when the CPS in response to IPBs has just emerged, and at 6 years, when language abilities are further developed. Results revealed that 6-year-olds, but not 3-year-olds, show the CPS in response to IPBs without full prosodic marking. These results indicate developmental differences with respect to the role of pausing as a prosodic boundary cue in German. The correlation of children's IPB perception and their syntactic abilities further corroborates the close prosody–syntax interaction in children's advancing ability to process phrase structure. [Copyright &y& Elsevier]

• Transition between developmental stages of non-adjacent dependency (NAD) learning. • Children between 1 and 3 years of age showed learning of NADs in a foreign language. • Brain responses revealed associative NAD learning, triggered by passive listening. • Gradual decrease of the strength of associative non-adjacent dependency learning. In order to become proficient native speakers, children have to learn the morpho-syntactic relations between distant elements in a sentence, so-called non-adjacent dependencies (NADs). Previous research suggests that NAD learning in children comprises different developmental stages, where until 2 years of age children are able to learn NADs associatively under passive listening conditions, while starting around the age of 3–4 years children fail to learn NADs during passive listening. To test whether the transition between these developmental stages occurs gradually, we tested children's NAD learning in a foreign language using event-related potentials (ERPs). We found ERP evidence of NAD learning across the ages of 1, 2 and 3 years. The amplitude of the ERP effect indexing NAD learning, however, decreased with age. These findings might indicate a gradual transition in children's ability to learn NADs associatively. Cognitively, this transition might be driven by children's increasing knowledge of their native language, hindering NAD learning in novel contexts. Neuroanatomically, maturation of the prefrontal cortex might play a crucial role, promoting top-down learning, affecting bottom-up, associative learning. In sum, our study suggests that NAD learning under passive listening conditions undergoes a gradual transition between different developmental stages during early childhood. [ABSTRACT FROM AUTHOR]

• ERPs during training showed a word-form familiarity effect over time. • ERPs at training showed a pairing consistency effect over time. • ERPs at test showed lateralized N400-like responses to violated sound-word pairs. • Infants can learn novel words for sounds in a similar way as for visual objects. Despite the prominence of non-visual semantic features for some words (e.g., siren or thunder), little is known about when and how the meanings of those words that refer to auditory objects can be acquired in early infancy. With associative learning being an important mechanism of word learning, we ask the question whether associations between sounds and words lead to similar learning effects as associations between visual objects and words. In an event-related potential (ERP) study, 10- to 12-month-old infants were presented with pairs of environmental sounds and pseudowords in either a consistent (where sound-word mapping can occur) or inconsistent manner. Subsequently, the infants were presented with sound-pseudoword combinations either matching or violating the consistent pairs from the training phase. In the training phase, we observed word-form familiarity effects and pairing consistency effects for ERPs time-locked to the onset of the word. The test phase revealed N400-like effects for violated pairs as compared to matching pairs. These results indicate that associative word learning is also possible for auditory objects before infants' first birthday. The specific temporal occurrence of the N400-like effect and topological distribution of the ERPs suggests that the object's modality has an impact on how novel words are processed. [ABSTRACT FROM AUTHOR]

• Non-adjacent dependency learning shows a developmental shift during the third year of life. • 2-year-old children can learn non-adjacent dependencies in linguistic material from passive listening, while 3-year-old children cannot. • Non-adjacent dependency learning in 2-year-olds is subserved by left-hemisphere temporal, inferior frontal and parietal brain regions. • The developmental trajectory for non-adjacent dependency learning differs between the linguistic and the non-linguistic domain. Non-adjacent dependencies (NADs) are important building blocks for language and extracting them from the input is a fundamental part of language acquisition. Prior event-related potential (ERP) studies revealed changes in the neural signature of NAD learning between infancy and adulthood, suggesting a developmental shift in the learning route for NADs. The present study aimed to specify which brain regions are involved in this developmental shift and whether this shift extends to NAD learning in the non-linguistic domain. In two experiments, 2- and 3-year-old German-learning children were familiarized with either Italian sentences or tone sequences containing NADs and subsequently tested with NAD violations, while functional near-infrared spectroscopy (fNIRS) data were recorded. Results showed increased hemodynamic responses related to the detection of linguistic NAD violations in the left temporal, inferior frontal, and parietal regions in 2-year-old children, but not in 3-year-old children. A different developmental trajectory was found for non-linguistic NADs, where 3-year-old, but not 2-year-old children showed evidence for the detection of non-linguistic NAD violations. These results confirm a developmental shift in the NAD learning route and point to distinct mechanisms underlying NAD learning in the linguistic and the non-linguistic domain. [ABSTRACT FROM AUTHOR]