Sleep Promotes Phonological Learning in Children Across Language and Autism Spectra

Abstract

Purpose Establishing stable and flexible phonological representations is a key component of language development and one which is thought to vary across children with neurodevelopmental disorders affecting language acquisition. Sleep is understood to support the learning and generalization of new phonological mappings in adults, but this remains to be examined in children. This study therefore explored the time course of phonological learning in childhood and how it varies by structural language and autism symptomatology. Method Seventy-seven 7- to 13-year-old children, 30 with high autism symptomatology, were included in the study; structural language ability varied across the sample. Children learned new phonological mappings based on synthesized speech tokens in the morning; performance was then charted via repetition (without feedback) over 24 hr and followed up 4 weeks later. On the night following learning, children's sleep was monitored with polysomnography. Results A period of sleep but not wake was associated with improvement on the phonological learning task in childhood. Sleep was associated with improved performance for both trained items and novel items. Structural language ability predicted overall task performance, though language ability did not predict degree of change from one session to the next. By contrast, autism symptomatology did not explain task performance. With respect to sleep architecture, rapid eye movement features were associated with greater phonological generalization. Conclusions Children's sleep was associated with improvement in performance on both trained and novel items. Phonological generalization was associated with brain activity during rapid eye movement sleep. This study furthers our understanding of individual differences in the acquisition of new phonological mappings and the role of sleep in this process over childhood. Supplemental Material https://doi.org/10.23641/asha.11126732

The Engage with Developmental Language Disorder (E‐DLD) project: Cohort profile

“…The literature indicates that children with language difficulties may have more sleep difficulties (Botting & Baraka, 2018). We have replicated previous research showing increased rates of caregiver reported sleep problems in children with DLD (Botting & Baraka, 2018; Knowland et al., 2021). However, research objectively measuring sleep behaviour in children with DLD has not found worse sleep outcomes or sleep efficiency (Knowland et al., 2021).…”

Sleep in Children with Autism Spectrum Disorder: A Narrative Review and Systematic Update

“…Sleep in autism is associated with (1) demographic factors [ 75 – 77 ], (2) challenging behaviors [ 36 , 78 – 87 ], (3) core ASD symptoms [ 38 , 65 , 77 ], and (4) other psychiatric symptoms [ 84 , 88 , 89 ]. Studies with a developmental focus also document correlations with executive functioning [ 88 , 90 ], memory [ 91 – 93 ], attention [ 79 , 94 ], and phonological learning [ 95 ].…”

Sleep problems effect on developmental trajectories in children with autism

“…The This data also adds to the research of how language acquisition is affected by sleep problems in ASD. Few studies focused on this topic and all of them used vocabulary to assess the effect of sleep problems on language (Botting & Baraka, 2018;Fletcher et al, 2020;Knowland et al, 2019). Going forward, one would suggest shifting focus toward receptive and expressive language.…”

“…Sleep problems have also been reported to affect children’s cognitive development and language acquisition. Multiple studies have shown that improved retention of vocabulary, phonological learning, and language comprehension skills are associated with greater amounts of sleep both in neurotypical children (Axelsson et al, 2016; Henderson et al, 2012) and in children with various developmental disorders (Axelsson et al, 2013; Edgin et al, 2015; Fletcher et al, 2020; Greiner de Magalhães et al, 2020; Knowland et al, 2019). Conversely, it has been shown that children who sleep less have more trouble with consolidation of different elements of memory associated with speech, such as phoneme recognition, vocabulary, and semantic knowledge (Axelsson et al, 2016; Bonuck et al, 2021; Henderson et al, 2012).…”