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Purpose: As a class, fricatives are more 'resistant' to consonant-vowel coarticulation than other English sounds. This study investigates the relative coarticulatory resistance of /0, s, /[??] in child and adult speech to better understand the acquisition of individuated speech sounds. Method: Ten 5-year-old children, seven 8-year-old children, and nine college-age adults produced [eFV] sequences in carrier phrases, where F was /0/, /s/, or /[??]/ and V was /ae/, /i/, or /u/. In Experiment 1, coarticulation was perceptually indexed: 65 adults predicted the target stressed vowel based on forward-gated audiovisual speech samples for a subset of four speakers from each age group. In Experiment 2, dynamic spectral measures of the /eFV/ sequences were analyzed using smoothing spline analysis of variance to again test for vowel effects on fricative articulation across age groups. Results: The perceptual results indicated that fricatives blocked vowel-vowel coarticulation across speaker age groups. Contrary to expectation, vowels were most accurately predicted when F was /s/ and not when it was /[??]/ or /0/ across age groups. Acoustic results indicated the expected biomechanically motivated /[??]/ > /s/ > /0/ coarticulatory resistance hierarchy in adults' speech. By contrast, /[??]/ > /s/ were similarly influenced by context in 8-year-olds' speech, and the results from 5-year-olds' speech suggested an influence of order of acquisition in that /0/ was surprisingly resistant to coarticulation. Conclusion: The study results are taken to suggest that a temporal constraint on fricative articulation interacts with biomechanical constraints during development to influence patterns of coarticulation in school-age children's speech., Speech sound acquisition is typically approached from a phonemic perspective (e.g., Dodd et al., 2003; Prather et al., 1975; Smit et al., 1990). Studies focus on how children do or [...]

: Introduction: The population of 16 million children exposed to HIV and uninfected (CHEU) under 15 years of age continues to expand rapidly, and the estimated prevalence of CHEU exceeds 20% in several countries in sub‐Saharan Africa with high HIV prevalence. Some evidence suggests that CHEU experience suboptimal neurodevelopmental outcomes compared to children born to women without HIV. In this commentary, we discuss the latest research on biologic and socio‐behavioural factors associated with neurodevelopmental outcomes among CHEU. Discussion: Some but not all studies have noted that CHEU are at risk of poorer neurodevelopment across multiple cognitive domains, most notably in language and motor skills, in diverse settings, ages and using varied assessment tools. Foetal HIV exposure can adversely influence infant immune function, structural brain integrity and growth trajectories. Foetal exposure to antiretrovirals may also influence outcomes. Moreover, general, non‐CHEU‐specific risk factors for poor neurodevelopment, such as preterm birth, food insecurity, growth faltering and household violence, are amplified among CHEU; addressing these factors will require multi‐factorial solutions. There is a need for rigorous harmonised approaches to identify children at the highest risk of delay. In high‐burden HIV settings, existing maternal child health programmes serving the general population could adopt structured early child development programmes that educate healthcare workers on CHEU‐specific risk factors and train them to conduct rapid neurodevelopmental screening tests. Community‐based interventions targeting parent knowledge of optimal caregiving practices have shown to be successful in improving neurodevelopmental outcomes in children and should be adapted for CHEU. Conclusions: CHEU in sub‐Saharan Africa have biologic and socio‐behavioural factors that may influence their neurodevelopment, brain maturation, immune system and overall health and wellbeing. Multidisciplinary research is needed to disentangle complex interactions between contributing factors. Common environmental and social risk factors for suboptimal neurodevelopment in the general population are disproportionately magnified within the CHEU population, and it is, therefore, important to draw on existing knowledge when considering the socio‐behavioural pathways through which HIV exposure could impact CHEU neurodevelopment. Approaches to identify children at greatest risk for poor outcomes and multisectoral interventions are needed to ensure optimal outcomes for CHEU in sub‐Saharan Africa., INTRODUCTION Successful prevention of vertical infant HIV acquisition has resulted in an expanding population of 16 million children exposed to HIV and uninfected (CHEU) under 15 years of age, according [...]

Introduction: Predictors of neurodevelopment among children who are HIV‐exposed uninfected (CHEU) are poorly understood. Methods: Mothers with and without HIV and their children were enrolled during 6‐week postnatal care visits across seven sites in Kenya between March 2021 and June 2022. Infant neurodevelopment was assessed using the Malawi Developmental Assessment Tool, including social, language, fine motor and gross motor domains. We used multivariate linear mixed effects models to identify associations between 1‐year neurodevelopment scores, HIV and antiretroviral therapy (ART) exposures, and household factors, adjusted for potential confounders and clustered by the site. Results: At 1‐year evaluation, CHEU (n = 709) and children who are HIV‐unexposed uninfected (CHUU) (n = 715) had comparable median age (52 weeks) and sex distribution (49% vs. 52% female). Mothers living with HIV were older (31 vs. 27 years), had lower education (50% vs. 26% primary) and were more likely to be report moderate‐to‐severe food insecurity (26% vs. 9%) (p < 0.01 for all). Compared to CHUU, CHEU had higher language scores (adjusted coeff: 0.23, 95% CI: 0.06, 0.39) and comparable social, fine and gross motor scores. Among all children, preterm birth was associated with lower gross motor scores (adjusted coeff: −1.38, 95% CI: −2.05, −0.71), food insecurity was associated with lower social scores (adjusted coeff: −0.37, 95% CI: −0.73, −0.01) and maternal report of intimate partner violence (IPV) was associated with lower fine motor (adjusted coeff: −0.76, 95% CI: −1.40, −0.13) and gross motor scores (adjusted coeff: −1.07, 95% CI: −1.81, −0.33). Among CHEU, in utero efavirenz (EFV) exposure during pregnancy was associated with lower gross motor scores compared to dolutegravir (DTG) exposure (adjusted coeff: −0.51, 95% CI: −1.01, −0.03). Lower fine and gross motor scores were also associated with having a single or widowed mother (adjusted coeff: −0.45, 95% CI: −0.87, −0.03) or a deceased or absent father (adjusted coeff: −0.81, 95% CI: −1.58, −0.05), respectively. Conclusions: Biologic and social factors were associated with child neurodevelopment. Despite socio‐demographic differences between CHEU and CHUU, 1‐year neurodevelopment was similar. Addressing IPV and food insecurity may provide benefits regardless of maternal HIV status. DTG use was associated with higher neurodevelopmental scores in CHEU, compared to EFV regimens, potentially contributing to a lack of neurodevelopmental difference between CHEU and CHUU., INTRODUCTION Successful prevention of vertical transmission programmes over the last decade has contributed to a rapidly growing population of almost 16 million children who are HIV‐exposed uninfected (CHEU) around the [...]