The modern cochlear implant (CI) is the most successful neural prosthesis developed to date. CIs provide hearing to the profoundly hearing impaired and allow the acquisition of spoken language in ...children born deaf. Results from studies enabled by the CI have provided new insights into (
a
) minimal representations at the periphery for speech reception, (
b
) brain mechanisms for decoding speech presented in quiet and in acoustically adverse conditions, (
c
) the developmental neuroscience of language and hearing, and (
d
) the mechanisms and time courses of intramodal and cross-modal plasticity. Additionally, the results have underscored the interconnectedness of brain functions and the importance of top-down processes in perception and learning. The findings are described in this review with emphasis on the developing brain and the acquisition of hearing and spoken language.
Background
There is wide variation in language abilities among young children with autism spectrum disorders (ASD), with some toddlers developing age‐appropriate language while others remain ...minimally verbal after age 5. Conflicting findings exist regarding predictors of language outcomes in ASD and various methodological issues limit the conclusions that can be drawn about factors associated with positive language growth that could provide insights into more effective intervention approaches for increasing communication skills.
Methods
Language development was investigated in 129 children with ASD participating in four assessments from mean age 2½ years (Visit 1) through 5½ years (Visit 4). Language ability was measured by a clinician‐administered test of comprehension and production. Hierarchical linear modeling was used to identify predictors of language ability. Stability of language status was examined in subgroups of Preverbal versus Verbal children identified at Visit 1. Discriminant function analysis was used to classify another subset of cases according to Low Language (minimally verbal) versus High Language outcome at Visit 4.
Results
ASD severity was a significant predictor of growth in both language comprehension and production during the preschool period, while cognition predicted growth in production. For the highest and lowest language performers at Visit 4, cognition, maternal education, and response to joint attention correctly classified over 80% of total cases. The vast majority of children who were preverbal at 2½ years attained some level of verbal skills by 5½ years.
Conclusions
Findings indicate that it is possible, by 2½ years, to predict language growth for children with ASD across the preschool years and identify factors that discriminate between children who remain minimally verbal at 5½ years from those with high language proficiency. Results suggest that early intervention focused on reducing core ASD symptoms may also be important for facilitating language development in young children with ASD.
For generations the study of vocal development and its role in language has been conducted laboriously, with human transcribers and analysts coding and taking measurements from small recorded ...samples. Our research illustrates a method to obtain measures of early speech development through automated analysis of massive quantities of day-long audio recordings collected naturalistically in children's homes. A primary goal is to provide insights into the development of infant control over infrastructural characteristics of speech through large-scale statistical analysis of strategically selected acoustic parameters. In pursuit of this goal we have discovered that the first automated approach we implemented is not only able to track children's development on acoustic parameters known to play key roles in speech, but also is able to differentiate vocalizations from typically developing children and children with autism or language delay. The method is totally automated, with no human intervention, allowing efficient sampling and analysis at unprecedented scales. The work shows the potential to fundamentally enhance research in vocal development and to add a fully objective measure to the battery used to detect speech-related disorders in early childhood. Thus, automated analysis should soon be able to contribute to screening and diagnosis procedures for early disorders, and more generally, the findings suggest fundamental methods for the study of language in natural environments.
Young children with autism spectrum disorder (ASD) present with a broad range of spoken language abilities, as well as delays in precursor skills such as gesture production and joint attention ...skills. While standardized assessments describe language strengths, the
Communication and Symbolic Behavior Scales
(CSBS-DP) is a particularly robust measure as it additionally characterizes precise aspects of social communication. This study provides a unique contribution by assessing the interactional effects of CSBS-DP Social Composite performance with early language samples on later language outcomes. Our results indicate that multiple social communication elements significantly interact with early spoken language to predict later language. Our findings also highlight the transactional relationship between early spoken vocabulary and social communication skills that bolster language development growth.
To determine the association between maternal serum 25(OH)-vitamin D concentrations during a critical window of fetal neurodevelopment and behavioral, emotional, and language outcomes of offspring.
...Serum 25(OH)-vitamin D concentrations of 743 Caucasian women in Perth, Western Australia (32°S) were measured at 18 weeks pregnancy and grouped into quartiles. Offspring behavior was measured with the Child Behavior Checklist at 2, 5, 8, 10, 14, and 17 years of age (n range = 412-652). Receptive language was assessed with the Peabody Picture Vocabulary Test-Revised at ages 5 (n = 534) and 10 (n = 474) years. Raw scores were converted to standardized scores, incorporating cutoffs for clinically significant levels of difficulty.
χ(2) analyses revealed no significant associations between maternal 25(OH)-vitamin D serum quartiles and offspring behavioral/emotional problems at any age. In contrast, there were significant linear trends between quartiles of maternal vitamin D levels and language impairment at 5 and 10 years of age. Multivariate regression analyses, incorporating a range of confounding variables, found that the risk of women with vitamin D insufficiency (≤46 nmol/L) during pregnancy having a child with clinically significant language difficulties was increased close to twofold compared with women with vitamin D levels >70 nmol/L.
Maternal vitamin D insufficiency during pregnancy is significantly associated with offspring language impairment. Maternal vitamin D supplementation during pregnancy may reduce the risk of developmental language difficulties among their children.
Creatine is physiologically provided equally by diet and by endogenous synthesis from arginine and glycine with successive involvements of arginine glycine amidinotransferase AGAT and ...guanidinoacetate methyl transferase GAMT. A specific plasma membrane transporter, creatine transporter CRTR (SLC6A8), further enables cells to incorporate creatine and through uptake of its precursor, guanidinoacetate, also directly contributes to creatine biosynthesis. Breakthrough in the role of creatine has arisen from studies on creatine deficiency disorders. Primary creatine disorders are inherited as autosomal recessive (mutations affecting GATM for glycine-amidinotransferase, mitochondrial) and GAMT genes) or X-linked (SLC6A8 gene) traits. They have highlighted the role of creatine in brain functions altered in patients (global developmental delay, intellectual disability, behavioral disorders). Creatine modulates GABAergic and glutamatergic cerebral pathways, presynaptic CRTR (SLC6A8) ensuring re-uptake of synaptic creatine. Secondary creatine disorders, addressing other genes, have stressed the extraordinary imbrication of creatine metabolism with many other cellular pathways. This high dependence on multiple pathways supports creatine as a cellular sensor, to cell methylation and energy status. Creatine biosynthesis consumes 40% of methyl groups produced as S-adenosylmethionine, and creatine uptake is controlled by AMP activated protein kinase, a ubiquitous sensor of energy depletion. Today, creatine is considered as a potential sensor of cell methylation and energy status, a neurotransmitter influencing key (GABAergic and glutamatergic) CNS neurotransmission, therapeutic agent with anaplerotic properties (towards creatine kinases creatine–creatine phosphate cycle and creatine neurotransmission), energetic and antioxidant compound (benefits in degenerative diseases through protection against energy depletion and oxidant species) with osmolyte behavior (retention of water by muscle). This review encompasses all these aspects by providing an illustrated metabolic account for brain and body creatine in health and disease, an algorithm to diagnose metabolic and gene bases of primary and secondary creatine deficiencies, and a metabolic exploration by 1H-MRS assessment of cerebral creatine levels and response to therapeutic measures.
•Primary creatine disorders highlight a role of creatine in brain physiology.•SLC6A8 takes part in creatine transport and re-uptake but also in biosynthesis.•Secondary creatine defects stress dependence of creatine metabolism on many pathways.•The high dependence on multiple metabolic pathways supports creatine as a cell sensor.•Creatine is a potential sensor of cell methylation and energy status.
Abstract A clear understanding of how to best provide clinical serves to bilingual children with suspected or confirmed primary language impairment (PLI) is predicated on understanding typical ...development in dual-language learners as well as the PLI profile. This article reviews general characteristics of children learning two languages, including three that challenge the diagnosis and treatment of PLI; uneven distribution of abilities in the child's two languages, cross-linguistic associations within bilingual learners, and individual variation in response to similar social circumstances. The diagnostic category of PLI (also referred to in the literature as specific language impairment or SLI) is described with attention to how language impairment, in the face of otherwise typical development, manifests in children learning two languages. Empirical evidence related to differential diagnosis of PLI in bilingual children is then reviewed and issues related to the generalization of treatment gains in dual-language learners with PLI are introduced. Learning outcomes: As a result of this activity, the careful reader will be able to (1) describe general characteristics of typically developing dual-language learners, (2) explain how primary language impairment (PLI) manifests in bilingual children, and (3) identify key clinical issues and approaches to assessment and treatment on bilingual PLI.
Background
Little is known about the nature, range and prevalence of different subgroups in language trajectories extant in a population from 4 to 11 years. This hinders strategic targeting and ...design of interventions, particularly targeting those whose difficulties will likely persist.
Methods
Children's language abilities from 4 to 11 years were investigated in a specialist language longitudinal community cohort (N = 1,910). Longitudinal trajectory latent class modelling was used to characterise trajectories and identify subgroups. Multinomial logistic regression was used to identify predictors associated with the language trajectories children followed.
Results
Three language trajectory groups were identified: ‘stable’ (94% of participants), ‘low‐decreasing’ (4%) and ‘low‐improving’ (2%). A range of child and family factors were identified that were associated with following either the low‐improving or low‐increasing language trajectory; many of them shared. The low‐improving group was associated with mostly environmental risks: non‐English‐speaking background, social disadvantage and few children's books in the home. The low‐decreasing group was associated with mainly biological risks: low birth weight, socioemotional problems, lower family literacy and learning disability.
Conclusions
By 4 years, services can be confident that most children with low language will remain low to 11 years. Using rigid cut‐points in language ability to target interventions is not recommended due to continued individual variability in language development. Service delivery models should incorporate monitoring over time, targeting according to language abilities and associated risks and delivery of a continuum of interventions across the continuum of need.
Primary care pediatricians and a variety of specialist physicians strive to define an accurate diagnosis for children presenting with impairment of expressive speech and delay in achieving ...developmental milestones. Within the past two decades, a group of disorders featuring this presentation have been identified as cerebral creatine deficiency syndromes (CCDS). Patients with these disorders were initially discerned using proton magnetic resonance spectroscopy of the brain within a magnetic resonance imaging (MRI) examination. The objective of this review is to provide the clinician with an overview of the current information available on identifying and treating these conditions. We explain the salient features of creatine metabolism, synthesis, and transport required for normal development. We propose diagnostic approaches for confirming a CCDS diagnosis. Finally, we describe treatment approaches for managing patients with these conditions.
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