Accessing, integrating and inhibiting word meaning in poor comprehenders

This study examined three processes crucial to reading comprehension (semantic access, integration, and inhibition) to identify causes of comprehension impairment. Poor comprehenders were compared to chronological-age controls and vocabulary-age (VA) controls. When listening to homonym primes (“bank”) versus unrelated primes, controls were faster to name pictures related to dominant (money) and subordinate (river) meanings at 250 ms interstimulus interval (ISI) but only showed dominant priming at 1,000 ms ISI, whereas poor comprehenders only showed dominant priming. When listening to subordinately biased sentences ending in homonyms (“John fished from the bank”) versus control sentences, all groups showed priming when naming subordinate (appropriate) pictures at 250 ms ISI: VA controls and poor comprehenders also showed priming when naming dominant (inappropriate) pictures. At 1,000 ms ISI, controls showed appropriate priming, whereas poor comprehenders only showed inappropriate priming. These findings suggest that poor comprehenders have difficulties accessing subordinate word meanings, which can manifest as a failure to inhibit irrelevant information

Consolidation of vocabulary during sleep : the rich get richer?

Sleep plays a role in strengthening new words and integrating them with existing vocabulary knowledge, consistent with neural models of learning in which sleep supports hippocampal transfer to neocortical memory. Such models are based on adult research, yet neural maturation may mean that the mechanisms supporting word learning vary across development. Here, we propose a model in which children may capitalise on larger amounts of slow-wave sleep to support a greater demand on learning and neural reorganisation, whereas adults may benefit from a richer knowledge base to support consolidation. Such an argument is reinforced by the well-reported “Matthew effect”, whereby rich vocabulary knowledge is associated with better acquisition of new vocabulary. We present a meta-analysis that supports this association between children’s existing vocabulary knowledge and their integration of new words overnight. Whilst multiple mechanisms likely contribute to vocabulary consolidation and neural reorganisation across the lifespan, we propose that contributions of existing knowledge should be rigorously examined in developmental studies. Such research has potential to greatly enhance neural models of learning

Retrieval practice transfer effects for multielement event triplets

Retrieval practice (RP) leads to improved retention relative to re-exposure and is considered a robust phenomenon when the final test conditions are identical to RP conditions. However, the extent to which RP ‘transfers' to related material is less clear. Here, we tested for RP transfer effects under conditions known to induce integration of associated material at encoding, which may make transfer more likely. Participants learned multielement triplets (locations, animals and objects) and one pairwise association from each triplet was tested through RP, re-exposed, or not re-exposed (control). Two days later participants completed a final test of all pairwise associations. We found no evidence for an RP effect compared to re-exposure, but both tested/re-exposed pairs were better remembered than the not re-exposed control condition. We also found that transfer occurred from both tested to untested and re-exposed to not re-exposed pairs. Our results highlight that RP and re-exposure can boost retention for directly tested/re-exposed event pairs and associated but untested/not re-exposed event pairs, suggesting re-exposure of integrated information can be of pedagogical value. The results also question the boundary conditions for an increase in retention for RP relative to re-exposure, highlighting the need for a better theoretical understanding of RP effects

Stronger Associations Between Sleep and Mental Health in Adults with Autism: A UK Biobank Study

This study examined sleep and its cognitive and affective correlates in adults with and without autism spectrum disorder (ASD), utilizing UK Biobank data. There were no group differences in subjective sleep duration [n = 220 ASD; n = 2200 general population (GP)]. Accelerometer measures of sleep duration or nighttime activity did not differ by group, but sleep efficiency was marginally lower in ASD (n = 83 ASD; n = 824 GP). Sleep efficiency was associated with wellbeing and mental health, and pathways between accelerometer sleep measures and wellbeing and mental health were significantly stronger for adults with ASD (who also reported substantially poorer wellbeing and > 5 × likelihood of experiencing mental distress). These findings highlight the need to monitor sleep to maintain good mental health in adult ASD

Does the maturation of early sleep patterns predict language ability at school entry? : A Born in Bradford study

Children's vocabulary ability at school entry is highly variable and predictive of later language and literacy outcomes. Sleep is potentially useful in understanding and explaining that variability, with sleep patterns being predictive of global trajectories of language acquisition. Here, we looked to replicate and extend these findings. Data from 354 children (without English as an additional language) in the Born in Bradford study were analysed, describing the mean intercepts and linear trends in parent-reported day-time and night-time sleep duration over five time points between 6 and 36 months-of-age. The mean difference between night-time and day-time sleep was predictive of receptive vocabulary at age five, with more night-time sleep relative to day-time sleep predicting better language. An exploratory analysis suggested that socioeconomic status was predictive of vocabulary outcomes, with sleep patterns partially mediating this relationship. We suggest that the consolidation of sleep patterns acts as a driver of early language development

Neural Responses to Novel and Existing Words in Children with Autism Spectrum and Developmental Language Disorder

The formation of new phonological representations is key in establishing items in the mental lexicon. Phonological forms become stable with repetition, time and sleep. Atypicality in the establishment of new word forms is characteristic of children with developmental language disorder (DLD) and autism spectrum disorder (ASD), yet neural changes in response to novel word forms over time have not yet been directly compared in these groups. This study measured habituation of event-related-potentials (ERPs) to novel and known words within and between two sessions spaced 24 hours apart in typically developing (TD) children, and their peers with DLD or ASD. We hypothesised that modulation of the auditory N400 amplitude would mark real-time changes in lexical processing with habituation evident within and across sessions in the TD group, while the DLD group would show attenuated habituation within sessions, and the ASD group attenuated habituation between sessions. Twenty-one typically developing children, 19 children with ASD, and 16 children with DLD listened passively to known and novel words on two consecutive days, while ERPs were recorded using dry electrodes. Counter to our hypotheses, no habituation effect emerged within sessions. However, responses did habituate between sessions, with this effect being reduced in the DLD group, indicating less pre-activation of lexical representations in response to words encountered the previous day. No differences in change over time were observed between the TD and ASD groups. These data are in keeping with theories stressing the importance of sleep-related consolidation in word learning

Training semantic long-term memory retrieval transfers to executive function and reading fluency

The retrieval of information from long-term memory is a fundamental cognitive ability, crucial for most aspects of successful human functioning. Whether and how long-term memory retrieval (LTMR) can be improved with training has clear societal importance but also theoretical value for furthering our understanding of underlying mechanisms. Here, we provide electrophysiological evidence for the plasticity of semantic LTMR. Thirty-five university students were randomly assigned to adaptive semantic LTMR training (using a Posner task) or to a non-adaptive version of the training. Before and after training they were assessed on measures of semantic LTMR, working memory, central executive function (interference control, switching), reading fluency, and fluid intelligence. Adaptive LTMR training (relative to non-adaptive training) led to significant improvements in semantic LTMR. The intervention group (in contrast to the control group) also showed a significant reduction in the mean amplitude of the N400 ERP component and 700–1000 ms measured during a semantic LTMR task, suggesting that changes in retrieval occurred at an early/automatic point and retrieval processing in semantic processing. Moreover, transfer effects were observed for switching, working memory and reading fluency, but not for interference control or fluid intelligence. These results point to the plasticity of semantic LTMR, and suggest that improvement in this ability can transfer to other domains for which LTMR is key