Jeremy Law

Morphological awareness and its role in compensation in adults with dyslexia

This study examines the role of morphological awareness (MA) in literacy achievement and compensation in word reading of adults with dyslexia through an exploration of three questions: (1) Do adult dyslexics demonstrate a deficit in MA, and how is this potential deficit related to phonological awareness (PA)? (2) Does MA contribute independently to literacy skills equally in dyslexics and control readers? and (3) Do MA and PA skills differ in compensated and noncompensated dyslexics? A group of dyslexic and normal reading university students matched for age, education and IQ participated in this study. Group analysis demonstrated an MA deficit in dyslexics; as well, MA was found to significantly predict a greater proportion of word reading and spelling within the dyslexic group compared with the controls. Compensated dyslexics were also found to perform significantly better on the morphological task than noncompensated dyslexics. Additionally, no statistical difference was observed in MA between the normal reading controls and the compensated group (independent of PA and vocabulary). Results suggest that intact and strong MA skills contribute to the achieved compensation of this group of adults with dyslexia. Implications for MA based intervention strategies for people with dyslexia are discussed.

The relationship of phonological ability, speech perception, and auditory perception in adults with dyslexia

This study investigated whether auditory, speech perception, and phonological skills are tightly interrelated or independently contributing to reading. We assessed each of these three skills in 36 adults with a past diagnosis of dyslexia and 54 matched normal reading adults. Phonological skills were tested by the typical threefold tasks, i.e., rapid automatic naming, verbal short-term memory and phonological awareness. Dynamic auditory processing skills were assessed by means of a frequency modulation (FM) and an amplitude rise time (RT); an intensity discrimination task (ID) was included as a non-dynamic control task. Speech perception was assessed by means of sentences and words-in-noise tasks. Group analyses revealed significant group differences in auditory tasks (i.e., RT and ID) and in phonological processing measures, yet no differences were found for speech perception. In addition, performance on RT discrimination correlated with reading but this relation was mediated by phonological processing and not by speech-in-noise. Finally, inspection of the individual scores revealed that the dyslexic readers showed an increased proportion of deviant subjects on the slow-dynamic auditory and phonological tasks, yet each individual dyslexic reader does not display a clear pattern of deficiencies across the processing skills. Although our results support phonological and slow-rate dynamic auditory deficits which relate to literacy, they suggest that at the individual level, problems in reading and writing cannot be explained by the cascading auditory theory. Instead, dyslexic adults seem to vary considerably in the extent to which each of the auditory and phonological factors are expressed and interact with environmental and higher-order cognitive influences.

The influences and outcomes of phonological awareness: a study of MA, PA and auditory processing in pre‐readers with a family risk of dyslexia

The direct influence of phonological awareness (PA) on reading outcomes has been widely demonstrated, yet PA may also exert indirect influence on reading outcomes through other cognitive variables such as morphological awareness (MA). However, PAs own development is dependent and influenced by many extraneous variables such as auditory processing, which could ultimately impact reading outcomes. In a group of pre-reading children with a family risk of dyslexia and low-risk controls, this study sets out to answer questions surrounding PAs relationship at various grain sizes (syllable, onset/rime and phoneme) with measures of auditory processing (frequency modulation (FM) and an amplitude rise-time task (RT)) and MA, independent of reading experience. Group analysis revealed significant differences between high- and low-risk children on measures of MA, and PA at all grain sizes, while a trend for lower RT thresholds of high-risk children was found compared with controls. Correlational analysis demonstrated that MA is related to the composite PA score and syllable awareness. Group differences on MA and PA were re-examined including PA and MA, respectively, as control variables. Results exposed PA as a relevant component of MA, independent of reading experience.

Predicting Future Reading Problems Based on Pre-reading Auditory Measures: A Longitudinal Study of Children with a Familial Risk of Dyslexia

Purpose: This longitudinal study examines measures of temporal auditory processing in pre-reading children with a family risk of dyslexia. Specifically, it attempts to ascertain whether pre-reading auditory processing, speech perception, and phonological awareness (PA) reliably predict later literacy achievement. Additionally, this study retrospectively examines the presence of pre-reading auditory processing, speech perception, and PA impairments in children later found to be literacy impaired. Method: Forty-four pre-reading children with and without a family risk of dyslexia were assessed at three time points (kindergarten, first, and second grade). Auditory processing measures of rise time (RT) discrimination and frequency modulation (FM) along with speech perception, PA, and various literacy tasks were assessed. Results: Kindergarten RT uniquely contributed to growth in literacy in grades one and two, even after controlling for letter knowledge and PA. Highly significant concurrent and predictive correlations were observed with kindergarten RT significantly predicting first grade PA. Retrospective analysis demonstrated atypical performance in RT and PA at all three time points in children who later developed literacy impairments. Conclusions: Although significant, kindergarten auditory processing contributions to later literacy growth lack the power to be considered as a single-cause predictor; thus results support temporal processing deficits contribution within a multiple deficit model of dyslexia.

Early development and predictors of morphological awareness: disentangling the impact of decoding skills and phonological awareness

BACKGROUNDnMorphological Awareness (MA) has been demonstrated to be influential on the reading outcomes of children and adults. Yet, little is known regarding MAs early development.nnnAIMnThe aim of this study is to better understand MA at different stages of development and its association with Phonological Awareness (PA) and reading.nnnMETHODS AND PROCEDURESnIn a longitudinal design the development of MA was explored in a group of pre-reading children with a family risk of dyslexia and age-matched controls from kindergarten up to and including grade 2.nnnOUTCOMES AND RESULTSnMA deficits were observed in the group with literacy difficulties at all time points. PA was only found to make a significant contribution to MA development at the early stages of formal reading instruction. While first-grade decoding skills were found to contribute significantly to MA in second grade.nnnCONCLUSIONSnEvidence supporting a bidirectional relation was found and supports the need for adequate MA intervention and explicit instruction for at risk children in the early stages of literacy instruction.

Morphological awareness and visual processing of derivational morphology in high-functioning adults with dyslexia: An avenue to compensation?

This study examined the processing of derivational morphology and its association with measures of morphological awareness and literacy outcomes in 30 Dutch-speaking high-functioning dyslexics, and 30 controls, matched for age and reading comprehension. A masked priming experiment was conducted where the semantic overlap between morphologically related pairs was manipulated as part of a lexical decision task. Measures of morphological awareness were assessed using a specifically designed sentence completion task. Significant priming effects were found in each group, yet adults with dyslexia were found to benefit more from the morphological structure than the controls. Adults with dyslexia were found to be influenced by both form (morpho-orthographic) and meaning (morphosemantic) properties of morphemes while controls were mainly influenced by morphosemantic properties. The reports suggest that morphological processing is intact in high-functioning dyslexics and a strength when compared to controls matched for reading comprehension and age. Thus, reports support morphological processing as a potential factor in the reading compensation of adults with dyslexia. However, adults with dyslexia performed significantly worse than controls on morphological awareness measures.