Children’s Neural Sensitivity to Prosodic Features of Natural Speech and Its Significance to Speech Development in Cochlear Implanted Children

Abstract

Catchy utterances, such as proverbs, verses, and nursery rhymes (i.e., “No pain, no gain” in English), contain strong-prosodic (SP) features and are child-friendly in repeating and memorizing; yet the way those prosodic features encoded by neural activity and their influence on speech development in children are still largely unknown. Using functional near-infrared spectroscopy (fNIRS), this study investigated the cortical responses to the perception of natural speech sentences with strong/weak-prosodic (SP/WP) features and evaluated the speech communication ability in 21 pre-lingually deaf children with cochlear implantation (CI) and 25 normal hearing (NH) children. A comprehensive evaluation of speech communication ability was conducted on all the participants to explore the potential correlations between neural activities and children’s speech development. The SP information evoked right-lateralized cortical responses across a broad brain network in NH children and facilitated the early integration of linguistic information, highlighting children’s neural sensitivity to natural SP sentences. In contrast, children with CI showed significantly weaker cortical activation and characteristic deficits in speech perception with SP features, suggesting hearing loss at the early age of life, causing significantly impaired sensitivity to prosodic features of sentences. Importantly, the level of neural sensitivity to SP sentences was significantly related to the speech behaviors of all children participants. These findings demonstrate the significance of speech prosodic features in children’s speech development.

Reduction of right-hemispheric auditory cortex activity in response to speech in more experienced paediatric cochlear implant users

“…Although there was a small trend in this direction, no such effect was observed in both CI groups and no differences between the FIXED and VARIABLE PROSODY conditions were evident. This finding is in line with two recent cross-sectional fNIRS studies (Chen et al, 2022;Wang et al, 2021) that also did not report right-lateralised processing of prosodic features in paediatric CI users. In addition to those two studies, the current results…”

“…For the NH controls, the fNIRS data showed right-lateralised responses to vowel sequences with prosodic variations, in agreement with our previous results obtained from NH adults (Steinmetzger et al, 2022a) and fNIRS data recorded from NH infants and children (Chen et al, 2022;Telkemeyer et al, 2011;Wartenburger et al, 2007) showing that prosodic variations elicit stronger activity in the right hemisphere. This lateralisation is thought to reflect that slow pitch changes, as found in speech and music, are preferentially processed by neural populations in the anterior part of the right superior temporal cortex (Johnsrude et al, 2000;Patterson et al, 2002;Zatorre & Belin, 2001).…”

“…This suggests that prior experience with normal acoustic hearing might be required to perceive these stimulus features. However, it should also be noted that both in the present experiment and the two other fNIRS studies that investigated the cortical processing of prosody in paediatric CI users (Chen et al, 2022;Wang et al, 2021), response amplitudes were very small in comparison to the respective NH control groups. The low signal-to-noise ratio of the data therefore made it difficult to reveal differences between experimental conditions as well as the two CI groups.…”

“…Furthermore, changes in speech-evoked cortical activity were so far only assessed during the first few months after implantation (Petersen et al, 2013; Sevy et al, 2010; Wang et al, 2022) and it thus remains unclear if left-lateralised activity in pre-lingually deafened paediatric CI users might emerge with more CI experience. Additionally, only two fNIRS studies to date investigated the cortical processing of prosodic features in paediatric CI users (Chen et al, 2022; Wang et al, 2021) and neither of them reported the right-lateralisation of activity in response to prosodic modulations typically observed in NH infants (Homae et al, 2006; Homae et al, 2012; Telkemeyer et al, 2011) and children (Wartenburger et al, 2007). Yet, both of them were cross-sectional studies and provide no information regarding neuroplastic changes following implantation.…”

Gemination in Child Egyptian Arabic: A Corpus-Based Study

“…This research demonstrates that children acquiring Egyptian Arabic are attuned to the moraic structure of their language from an early age and actively employ gemination to maintain this structure in their speech. These findings contribute to the growing body of evidence suggesting that children are sensitive to the prosodic features of their native language (Everhardt et al 2022;Chen et al 2022) and actively use this knowledge to navigate the challenges of speech production. By highlighting the specific ways in which Egyptian Arabic-speaking children utilize gemination in their early speech, this study paves the way for further research into the acquisition of language-specific phonological features and their role in shaping children's communicative competence.…”