Is that a pibu or a pibo? Children with reading and language deficits show difficulties in learning and overnight consolidation of phonologically similar pseudowords.

Word learning is critical for the development of reading and language comprehension skills. Although previous studies have indicated that word learning is compromised in children with reading disability (RD) or developmental language disorder (DLD), it is less clear how word learning difficulties manifest in children with comorbid RD and DLD. Furthermore, it is unclear whether word learning deficits in RD or DLD include difficulties with offline consolidation of newly learned words. In the current study, we employed an artificial lexicon learning paradigm with an overnight design to investigate how typically developing (TD) children (N = 25), children with only RD (N = 93), and children with both RD and DLD (N = 34) learned and remembered a set of phonologically similar pseudowords. Results showed that compared to TD children, children with RD exhibited: (i) slower growth in discrimination accuracy for cohort item pairs sharing an onset (e.g. pibu-pibo), but not for rhyming item pairs (e.g. pibu-dibu); and (ii) lower discrimination accuracy for both cohort and rhyme item pairs on Day 2, even when accounting for differences in Day 1 learning. Moreover, children with comorbid RD and DLD showed learning and retention deficits that extended to unrelated item pairs that were phonologically dissimilar (e.g. pibu-tupa), suggestive of broader impairments compared to children with only RD. These findings provide insights into the specific learning deficits underlying RD and DLD and motivate future research concerning how children use phonological similarity to guide the organization of new word knowledge.

Category learning in Poor Comprehenders.

Poor comprehenders (PCs) are characterized by poor reading comprehension despite intact decoding and general cognitive ability. Poor word meaning knowledge is one of the earliest deficits associated with a PC profile. We examined processes underpinning word learning in PCs using a category learning paradigm. Adolescent participants (20 TD, 19 PC, ages 13-18) learned novel categories with two key manipulations: information type (verbal vs. nonverbal) and training type (directed vs. undirected). We found that PCs showed more benefit from directed training than TD individuals overall; however, both groups performed similarly when receiving directed blocks first. Moreover, when undirected training was received first, TD individuals showed better performance in directed as compared to undirected blocks, whereas PCs who receive undirected training first showed no significant difference between training types. Our investigation indicates that PCs may have different strategies for learning, especially when their attention is not externally directed towards relevant features.

Common variation within the SETBP1 gene is associated with reading-related skills and patterns of functional neural activation.

Epidemiological population studies highlight the presence of substantial individual variability in reading skill, with approximately 5-10% of individuals characterized as having specific reading disability (SRD). Despite reported substantial heritability, typical for a complex trait, the specifics of the connections between reading and the genome are not understood. Recently, the SETBP1 gene has been implicated in several complex neurodevelopmental syndromes and disorders that impact language. Here, we examined the relationship between common polymorphisms in this gene, reading, and reading associated behaviors using data from an ongoing project on the genetic basis of SRD (n = 135). In addition, an exploratory analysis was conducted to examine the relationship between SETBP1 and brain activation using functional magnetic resonance imaging (fMRI; n = 73). Gene-based analyses revealed a significant association between SETBP1 and phonological working memory, with rs7230525 as the strongest associated single nucleotide polymorphism (SNP). fMRI analysis revealed that the rs7230525-T allele is associated with functional neural activation during reading and listening to words and pseudowords in the right inferior parietal lobule (IPL). These findings suggest that common genetic variation within SETBP1 is associated with reading behavior and reading-related brain activation patterns in the general population.

Electrophysiological Indices of Audiovisual Speech Perception: Beyond the McGurk Effect and Speech in Noise.

Visual information on a talker's face can influence what a listener hears. Commonly used approaches to study this include mismatched audiovisual stimuli (e.g., McGurk type stimuli) or visual speech in auditory noise. In this paper we discuss potential limitations of these approaches and introduce a novel visual phonemic restoration method. This method always presents the same visual stimulus (e.g., /ba/) dubbed with a matched auditory stimulus (/ba/) or one that has weakened consonantal information and sounds more /a/-like). When this reduced auditory stimulus (or /a/) is dubbed with the visual /ba/, a visual influence will result in effectively 'restoring' the weakened auditory cues so that the stimulus is perceived as a /ba/. An oddball design in which participants are asked to detect the /a/ among a stream of more frequently occurring /ba/s while either a speaking face or face with no visual speech was used. In addition, the same paradigm was presented for a second contrast in which participants detected /pa/ among /ba/s, a contrast which should be unaltered by the presence of visual speech. Behavioral and some ERP findings reflect the expected phonemic restoration for the /ba/ vs. /a/ contrast; specifically, we observed reduced accuracy and P300 response in the presence of visual speech. Further, we report an unexpected finding of reduced accuracy and P300 response for both speech contrasts in the presence of visual speech, suggesting overall modulation of the auditory signal in the presence of visual speech. Consistent with this, we observed a mismatch negativity (MMN) effect for the /ba/ vs. /pa/ contrast only that was larger in absence of visual speech. We discuss the potential utility for this paradigm for listeners who cannot respond actively, such as infants and individuals with developmental disabilities.

Neural representations for newly learned words are modulated by overnight consolidation, reading skill, and age.

Word learning depends not only on efficient online binding of phonological, orthographic and lexical information, but also on consolidation of new word representations into permanent lexical memory. Work on word learning under a variety of contexts indicates that reading and language skill impact facility of word learning in both print and speech. In addition, recent research finds that individuals with language impairments show deficits in both initial word form learning and in maintaining newly learned representations over time, implicating mechanisms associated with maintenance that may be driven by deficits in overnight consolidation. Although several recent studies have explored the neural bases of overnight consolidation of newly learned words, no extant work has examined individual differences in overnight consolidation at the neural level. The current study addresses this gap in the literature by investigating how individual differences in reading and language skills modulate patterns of neural activation associated with newly learned words following a period of overnight consolidation. Specifically, a community sample of adolescents and young adults with significant variability in reading and oral language (vocabulary) ability were trained on two spoken artificial lexicons, one in the evening on the day before fMRI scanning and one in the morning just prior to scanning. Comparisons of activation between words that were trained and consolidated vs. those that were trained but not consolidated revealed increased cortical activation in a number of language associated and memory associated regions. In addition, individual differences in age, reading skill and vocabulary modulated learning rate in our artificial lexicon learning task and the size of the cortical consolidation effect in the precuneus/posterior cingulate, such that older readers and more skilled readers had larger cortical consolidation effects in this learning-critical region. These findings suggest that age (even into late adolescence) and reading and language skills are important individual differences that affect overnight consolidation of newly learned words. These findings have significant implications for understanding reading and language disorders and should inform pedagogical models.

Understanding specific reading comprehension deficit: A review.

A substantial population of children and adolescents struggle with reading comprehension despite adequate phonemic decoding (word-level reading) and intellectual ability. Individuals with this pattern of performance are considered to have specific reading comprehension deficit(S-RCD).Despite two decades of study on the profiles of behavioral performance associated with S-RCD, there is no current consensus on the causal mechanisms of the disorder. Recent progress in identifying such mechanisms includes studies that have utilized comprehension age match and longitudinal designs which have identified several comprehension subskills that are predictive of S-RCD development. However, disagreement persists over which deficits are core to S-RCD, which are comorbid and which are simply a consequence of poor comprehension. Further, almost no research on this disorder has sought to identify neurobiological endophenotypes that may enhance our understanding of causal mechanisms. Here, we offer a review of the literature on core language and higher-level language deficits associated with S-RCD, including studies that examine the neurobiological basis of this disorder. What emerges is a relatively consistent pattern of subclinical impairments across a range of comprehension subskills that may put pressure on the complex process of reading comprehension. These subskills include semantic and grammatical processing, inference making, and other higher-level language skills such as comprehension monitoring. This disorder also appears to have a neurobiological basis, though further study is needed to establish the precise disruption in neurocircuitry. Suggestions for further research include the continued use of online, temporally-sensitive measures such as eye-tracking and event-related potential, additional studies of the neurobiology of the disorder, as well as longitudinal tracking and identification of early behavioral and brain markers for S-RCD prior to formal schooling.