Predicting and Evaluating Treatment Response: Evidence Toward Protracted Response Patterns for Severely Impacted Students With Dyslexia

Great strides have been made in the development of effective methods of instruction for children with dyslexia. However, individual response to treatment varies, and weaknesses persist for some students with dyslexia despite otherwise effective instruction. Continued efforts are needed to support the prospective identification of poor response, particularly in routine intervention settings. The current study addressed whether indicators of dyslexia risk as outlined by hybrid diagnostic models predict response in children who received Tier 3 dyslexia intervention in their schools. The program's efficacy has been previously documented in remediating reading abilities in children with dyslexia. Data were examined from 115 elementary-age children who received routine Tier 3 dyslexia intervention in their schools. Logistic regression revealed powerful effects of preintervention fluency and gender in predicting response, with weaker effects of decoding and rapid naming. Attention-deficit/hyperactivity disorder status also played a role in predicting response. Phonological awareness and listening-reading comprehension discrepancy did not predict response. Profile analyses indicated near- and far-transfer of skill for the adequate response group, whereas growth in the poor response group was limited to near-transfer. Findings support a continuum of severity that may be associated with less robust growth and generalization over the course of the intervention.

Exploring boundary conditions of the listening comprehension-reading comprehension discrepancy index

Conversations about the nature of dyslexia and how dyslexia impacts reading and listening comprehension get to the heart of classification and identification models of dyslexia. Recently, this conversation has been expanded to include efforts to estimate the prevalence of dyslexia in the population through the introduction of a discrepancy index of listening comprehension and reading comprehension. This discrepancy index was proposed to serve as a proxy for dyslexia when estimating its prevalence in the population. Individuals whose reading comprehension is considerably lower than their listening comprehension are thought to exhibit unexpected reading deficits. However, the index could underrepresent certain groups within the population. The current study explored this possibility using data from a sample of 4078 public-school students. We hypothesized that students from historically marginalized or otherwise disenfranchised groups (i.e., poor and minority groups) would be less likely to have a positive listening comprehension - reading comprehension (LC-RC) discrepancy index. Based on the results of multilevel linear mixed effect modeling, socioeconomic status (SES) contributed to differential performance on the discrepancy index when it was calculated using residual scores. Moreover, African American students were identified as having a reliably lower discrepancy index regardless of how it was calculated. It appears that this index, which only looks at the comprehension of language and not production, may, in fact, disadvantage students for whom oral language production differs from General American English (GAE). These outcomes suggest that this measure may lack the sensitivity to identify bidialectal students with dyslexia.

Characterizing the knowledge of educators across the tiers of instructional support

Translating the research base on effective reading instruction to the classroom has been a challenge. The delivery of these instructional methods requires practical skills coupled with an understanding of the aspects of language being taught. The purpose of this study was to explore the level of literacy knowledge of the English language held by educators who provide instruction to students in the primary grades. Data from 1369 classroom teachers, 74 reading interventionists, and 131 special educators comprising the analytic sample were collected as part of a training initiative in a US state. Participating educators completed a 50-item test of phonological sensitivity, phonemic awareness, decoding, encoding, and morphology. Multiple regression analyses confirmed differences in the levels of knowledge observed between the groups of educators. Reading interventionists demonstrated greater knowledge than classroom teachers and special educators in the total proportion of correct responses and across each domain. Classroom teachers demonstrated greater knowledge than special educators in phonological sensitivity and decoding but did not differ from each other in phonemic awareness, encoding, or morphology knowledge. Special educators provide intervention to students with the most severe forms of reading disabilities, yet they had the lowest level of knowledge. In contrast, reading interventionists, who provide intervention within general education, had the highest levels of knowledge. These findings suggest a need to elevate the knowledge of special educators and consider reading interventionists' role in supporting students identified with a specific learning disability in reading.

Morphological awareness and vocabulary predict reading resilience in adults

Resilient readers comprehend written language despite word reading deficits. The reading resiliency framework specifies candidate protective factors hypothesized to mitigate adverse effects on reading comprehension arising from phonological decoding deficiencies and, consequently, illuminates how some individuals exhibit relative reading resiliency. A focus on relative reading resiliency involves an examination of individual strengths and weaknesses because areas of relative strength can bolster one's abilities. The ability for morphological awareness and vocabulary to be strengths or protective factors contributing to reading resiliency was explored in a sample of university students. Morphological awareness is predicted to be a particularly important skill for university students due to the complexity of texts encountered in their coursework. A measure of word-level morphological awareness was positively associated with relative reading resiliency. Furthermore, across norm-referenced and standardized high-stakes testing measures of reading comprehension, vocabulary mediated the impact of morphological awareness on comprehension after controlling for phonological decoding ability. These findings suggest that morphological awareness and vocabulary skills are important contributing factors to reading comprehension and reading resilience.

External evaluations for dyslexia: do the data support parent concerns?

A grassroots movement of parents who fear that their children's reading struggles are going unrecognized at school has led to dyslexia laws in all but three states in the U.S. The current study was undertaken to provide data relevant to this topic by characterizing the reading profiles of 71 children referred for testing at a center specializing in the assessment of reading disabilities. These children were receiving instruction and intervention in reading across the tiers of instructional support in general and special education within their schools. On average, the children demonstrated equivalent deficits in print literacy skills on norm-referenced assessments regardless of the intensity of their reading support, and the majority of children who were only receiving tier 1 instruction exhibited characteristics of dyslexia. Moreover, 69% of children only receiving tier 1 instruction, and all remaining children, performed below benchmark expectations on a curriculum-based measure of oral reading fluency. While these data are not an evaluation of the implementation of the state's dyslexia laws or the statewide implementation of RTI, they provide data characterizing the real struggles and lack of identification of children whose parents seek an external evaluation of their children's reading skills. However, they are set in the context of a state in which 66% of public-school children cannot read proficiently by the end of the third grade. The reading struggles highlighted in this clinic referral sample are unexceptional in the larger state context.

Characteristics of Students Identified With Dyslexia Within the Context of State Legislation

All but seven U.S. states have laws that govern some aspects of dyslexia screening, intervention, or teacher training in public schools. However, in the three states that mandate child-level reporting, data indicate lower than expected rates of dyslexia identification when compared with commonly accepted dyslexia prevalence rates. To better understand this apparent mismatch, this study explores factors that might predict the school-assigned identification of individuals with dyslexia. Deidentified data on 7,947 second-grade students in 126 schools from one U.S. state included a universal screening measure of literacy skills indicative of dyslexia (i.e., reading and spelling), school-assigned dyslexia classification, and demographic characteristics. As expected, behavioral characteristics of dyslexia from universal screening were associated with school-assigned dyslexia classification. However, dyslexia classification was less likely for minority students and individuals attending schools with a higher percentage of minority students. Students who showed behavioral characteristics of dyslexia and attended schools with a higher proportion of other students with similar poor literacy skills were more likely not to receive a school-assigned dyslexia classification. The findings suggest systematic demographic differences in whether a student is identified with dyslexia by schools even when using universal screening.

Conjoint recognition procedures reveal verbatim processing enhances memory for emotionally valenced pictorial stimuli

Frequently, emotion is associated with enhancements in memory as long as arousal is not too extreme. Negative valence can also lead to increased false memories. Yet less is known about specific memory processes that drive these effects of emotional content on memory performance. The present study uses conjoint recognition analyses to investigate the memory processes associated with memory for negative and positive pictorial stimuli. Participants studied pictures, which had been rated as negative-arousing, positive-arousing, or neutral-non-arousing, before completing a recognition memory test 48 hr later. Contrary to initial expectations based on process-based estimates of emotional words, gist-based processing did not lead to high levels of true memory for negative pictures, nor were negative pictures associated with compellingly real false memories. Instead, negative pictures were recognized more frequently than neutral pictures, and this effect was related to increased verbatim-based identity judgments. However, emotional memory enhancements were not observed for positive pictures. These results indicate that emotional memory enhancements for negative pictures are related to enhanced verbatim processing of emotional material. When false memories did occur for negative pictures, they were because of gist-based similarity judgments as predicted by prior process-based estimates of false memory for negative-arousing words or pictures. Such results are discussed in terms of eyewitness memory and the processes underlying such remembering, because in many criminal and forensically relevant situations, witnesses, who are often victims as well, are asked to recognize the perpetrator or other arousing aspects of an event. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Brain basis of cognitive resilience: Prefrontal cortex predicts better reading comprehension in relation to decoding

OBJECTIVE

The ultimate goal of reading is to understand written text. To accomplish this, children must first master decoding, the ability to translate printed words into sounds. Although decoding and reading comprehension are highly interdependent, some children struggle to decode but comprehend well, whereas others with good decoding skills fail to comprehend. The neural basis underlying individual differences in this discrepancy between decoding and comprehension abilities is virtually unknown.

METHODS

We investigated the neural basis underlying reading discrepancy, defined as the difference between reading comprehension and decoding skills, in a three-part study: 1) The neuroanatomical basis of reading discrepancy in a cross-sectional sample of school-age children with a wide range of reading abilities (Experiment-1; n = 55); 2) Whether a discrepancy-related neural signature is present in beginning readers and predictive of future discrepancy (Experiment-2; n = 43); and 3) Whether discrepancy-related regions are part of a domain-general or a language specialized network, utilizing the 1000 Functional Connectome data and large-scale reverse inference from Neurosynth.org (Experiment-3).

RESULTS

Results converged onto the left dorsolateral prefrontal cortex (DLPFC), as related to having discrepantly higher reading comprehension relative to decoding ability. Increased gray matter volume (GMV) was associated with greater discrepancy (Experiment-1). Region-of-interest (ROI) analyses based on the left DLPFC cluster identified in Experiment-1 revealed that regional GMV within this ROI in beginning readers predicted discrepancy three years later (Experiment-2). This region was associated with the fronto-parietal network that is considered fundamental for working memory and cognitive control (Experiment-3).

INTERPRETATION

Processes related to the prefrontal cortex might be linked to reading discrepancy. The findings may be important for understanding cognitive resilience, which we operationalize as those individuals with greater higher-order reading skills such as reading comprehension compared to lower-order reading skills such as decoding skills. Our study provides insights into reading development, existing theories of reading, and cognitive processes that are potentially significant to a wide range of reading disorders.

Memory and functional brain differences in a national sample of U.S. veterans with Gulf War Illness

Roughly 26-32% of U. S. veterans who served in the 1991 Persian Gulf War report suffering from chronic health problems. Memory complaints are regularly reported by ill Gulf War veterans (GWV), but limited data verify their complaints. This study investigated episodic memory and brain function in a nationally representative sample of GWV, using a face-name memory task and functional magnetic resonance imaging during encoding. A syndrome classification system was used to subdivide ill GWV into the three major Gulf War Illness syndrome types, "impaired cognition" (GWV-1), "confusion ataxia" (GWV-2), and "central pain" (GWV-3). Memory and brain function of ill GWV were contrasted to deployed and nondeployed well GWV controls (GWV-C). Ill GWV exhibited impaired memory function relative to GWV-C but the patterns of functional brain differences varied. Brain activation differentiated the GWV-C from the ill GWV. The different syndrome types also differed from one another in several brain regions. Additionally, the current study was the first to observe differences in brain function between deployed and nondeployed GWV-C. These results provide (1) evidence of memory impairment in ill GWV and differentiate the syndrome types at a functional neurobiological level, and (2) the role of deployment in the war on brain function.

White matter morphometric changes uniquely predict children's reading acquisition

This study examined whether variations in brain development between kindergarten and Grade 3 predicted individual differences in reading ability at Grade 3. Structural MRI measurements indicated that increases in the volume of two left temporo-parietal white matter clusters are unique predictors of reading outcomes above and beyond family history, socioeconomic status, and cognitive and preliteracy measures at baseline. Using diffusion MRI, we identified the left arcuate fasciculus and superior corona radiata as key fibers within the two clusters. Bias-free regression analyses using regions of interest from prior literature revealed that volume changes in temporo-parietal white matter, together with preliteracy measures, predicted 56% of the variance in reading outcomes. Our findings demonstrate the important contribution of developmental differences in areas of left dorsal white matter, often implicated in phonological processing, as a sensitive early biomarker for later reading abilities, and by extension, reading difficulties.

Memory impairment exhibited by veterans with Gulf War Illness

Roughly 26-32% of US veterans, who served in the first Gulf War, report suffering from chronic health problems ( Golomb, 2008 , Proceedings of the National Academies of Science, 105, 4295). The present study investigated the memory deficits reported by these ill Gulf War veterans (GWV) using a face-name associative memory paradigm administered during functional magnetic resonance imaging (fMRI). The fMRI data confirmed memory performance on the memory task to be related to the amount of activation in the left hippocampus observed during the study. In addition, ill-GWV demonstrated decreased memory performance relative to unaffected GWV on this memory test, providing evidence of memory deficits using an objective measure of memory.

Functional connectivity between the left and right inferior frontal lobes in a small sample of children with and without reading difficulties

Individuals with dyslexia often demonstrate bilateral inferior frontal lobe activation while performing basic reading tasks. To investigate these findings, functional connectivity analyses were conducted on fMRI data collected from children with dyslexia, who did and did not respond well to treatment, and from non-impaired readers. Analysis of active and resting-state fMRI data across 15 participants revealed functional connections between the inferior frontal regions in non-impaired readers and treatment responders, but not in treatment non-responders. Analyses incorporating DTI data revealed associations with anterior corpus callosum structures. These results suggest that bilateral frontal functional connectivity is normative and may facilitate treatment response.

Brain connectivity in non-reading impaired children and children diagnosed with developmental dyslexia

Diffusion Tensor Imaging (DTI) was used to investigate the relationship between white matter and reading abilities in reading impaired and non-reading impaired children. Seventeen children (7 non-reading impaired, 10 reading impaired) participated in this study. DTI was performed with 2mm isotropic resolution to cover the entire brain along 30 noncollinear directions. Voxelwise analyses were conducted on data processed through Tract Based Spatial Statistics (TBSS). The data replicated previous results seen across multiple studies and extended findings to include measures of both real word and pseudoword decoding. Negative correlations were observed in the left posterior corpus callosum between fractional anisotropy (FA) values and both measures of decoding. Positive correlations between FA values and real word and pseudoword decoding were observed in the left superior corona radiata. This extension of findings regarding correlations between the corona radiata and reading skills suggests an important direction for future research into the neurological substrates of reading.