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

Grapheme-phoneme learning in an unknown orthography: a study in typical reading and dyslexic children

In this study, we examined the learning of new grapheme-phoneme correspondences in individuals with and without dyslexia. Additionally, we investigated the relation between grapheme-phoneme learning and measures of phonological awareness, orthographic knowledge and rapid automatized naming, with a focus on the unique joint variance of grapheme-phoneme learning to word and non-word reading achievement. Training of grapheme-phoneme associations consisted of a 20-min training program in which eight novel letters (Hebrew) needed to be paired with speech sounds taken from the participant's native language (Dutch). Eighty-four third grade students, of whom 20 were diagnosed with dyslexia, participated in the training and testing. Our results indicate a reduced ability of dyslexic readers in applying newly learned grapheme-phoneme correspondences while reading words which consist of these novel letters. However, we did not observe a significant independent contribution of grapheme-phoneme learning to reading outcomes. Alternatively, results from the regression analysis indicate that failure to read may be due to differences in phonological and/or orthographic knowledge but not to differences in the grapheme-phoneme-conversion process itself

Processing of structural neuroimaging data in young children:bridging the gap between current practice and state-of-the-art methods

The structure of the brain is subject to very rapid developmental changes during early childhood. Pediatric studies based on Magnetic Resonance Imaging (MRI) over this age range have recently become more frequent, with the advantage of providing in vivo and non-invasive high-resolution images of the developing brain, toward understanding typical and atypical trajectories. However, it has also been demonstrated that application of currently standard MRI processing methods that have been developed with datasets from adults may not be appropriate for use with pediatric datasets. In this review, we examine the approaches currently used in MRI studies involving young children, including an overview of the rationale for new MRI processing methods that have been designed specifically for pediatric investigations. These methods are mainly related to the use of age-specific or 4D brain atlases, improved methods for quantifying and optimizing image quality, and provision for registration of developmental data obtained with longitudinal designs. The overall goal is to raise awareness of the existence of these methods and the possibilities for implementing them in developmental neuroimaging studies

Detecting post-stroke aphasia using EEG-based neural envelope tracking of natural speech

[Objective]. After a stroke, one-third of patients suffer from aphasia, a language disorder that impairs communication ability. The standard behavioral tests used to diagnose aphasia are time-consuming and have low ecological validity. Neural tracking of the speech envelope is a promising tool for investigating brain responses to natural speech. The speech envelope is crucial for speech understanding, encompassing cues for processing linguistic units. In this study, we aimed to test the potential of the neural envelope tracking technique for detecting language impairments in individuals with aphasia (IWA). [Approach]. We recorded EEG from 27 IWA in the chronic phase after stroke and 22 controls while they listened to a story. We quantified neural envelope tracking in a broadband frequency range as well as in the delta, theta, alpha, beta, and gamma frequency bands using mutual information analysis. Besides group differences in neural tracking measures, we also tested its suitability for detecting aphasia using a Support Vector Machine (SVM) classifier. We further investigated the required recording length for the SVM to detect aphasia and to obtain reliable outcomes. [Results]. IWA displayed decreased neural envelope tracking compared to controls in the broad, delta, theta, and gamma band. Neural tracking in these frequency bands effectively captured aphasia at the individual level (SVM accuracy 84%, AUC 88%). High-accuracy and reliable detection could be obtained with 5-7 minutes of recording time. [Significance]. Our study shows that neural tracking of speech is an effective biomarker for aphasia. We demonstrated its potential as a diagnostic tool with high reliability, individual-level detection of aphasia, and time-efficient assessment. This work represents a significant step towards more automatic, objective, and ecologically valid assessments of language impairments in aphasia

Grapheme-Phoneme Learning in an Unknown Orthography: A Study in Typical Reading and Dyslexic Children

In this study, we examined the learning of new grapheme-phoneme correspondences in individuals with and without dyslexia. Additionally, we investigated the relation between grapheme-phoneme learning and measures of phonological awareness, orthographic knowledge and rapid automatized naming, with a focus on the unique joint variance of grapheme-phoneme learning to word and non-word reading achievement. Training of grapheme-phoneme associations consisted of a 20-min training program in which eight novel letters (Hebrew) needed to be paired with speech sounds taken from the participant's native language (Dutch). Eighty-four third grade students, of whom 20 were diagnosed with dyslexia, participated in the training and testing. Our results indicate a reduced ability of dyslexic readers in applying newly learned grapheme-phoneme correspondences while reading words which consist of these novel letters. However, we did not observe a significant independent contribution of grapheme-phoneme learning to reading outcomes. Alternatively, results from the regression analysis indicate that failure to read may be due to differences in phonological and/or orthographic knowledge but not to differences in the grapheme-phoneme-conversion process itself

De neurobiologische basis van dyslexie

In Handboek dyslexieonderzoek geven de auteurs, Vlaamse en Nederlandse onderzoekers die allen zelf een vooraanstaande plaats innemen in het internationale onderzoek, het wetenschappelijk onderzoek op het gebied van dyslexie op heel bevattelijke wijze weer. De auteurs gaan in op de diagnose, erfelijkheid, hersenonderzoek, cognitieve oorzaken, preventie en de behandeling van dyslexie. Het boek is daardoor uitstekend geschikt als handboek in zowel bachelor- als masteropleidingen, maar het is ook bijzonder informatief voor al wie professioneel betrokken is bij dyslexie. In bijna alle hoofdstukken wordt de relatie tussen theorie en praktijk ter harte genomen. Het boek vergt geen speciale voor- kennis en biedt de nodige verdieping in de materie.edition: firststatus: publishe

COGNITIVE AND NEUROANATOMICAL MARKERS OF DYSLEXIA: A categorical perception and diffusion tensor imaging study

This thesis focuses on the cognitive and neuroanatomical aspects of reading related subskills (such as phonology, orthography, speech perception and auditory processing) and on its dysfunction in dyslexia. The most prominent etiological theory on dyslexia postulates that the reading problems result from a phonological deficit, more specifically a deficit in the representation, storage and/or retrieval of speech sounds. It has been suggested that this phonological deficit is secondary to a more basic auditory deficit, but despite substantial research effort, the nature of these auditory problems remains hotly debated. A first controversy concerns the extent to which auditory problems in dyslexics are speech-specific, namely whether they can be reduced to basic auditory processing problems or whether they are phonetic in origin. A second topic of debate concerns the extent to which the auditory problems are specific to the processing of rapidly changing temporal information or whether they encompass a broader range of complex spectrotemporal processing. To address both questions within one test paradigm, we created a categorical perception task using four continua of similar acoustic complexity: (1) a speech contrast exploiting temporal cues (/ba/-/da/), (2) a speech contrast defined by non-temporal spectral cues (/u/-/y/), (3) a non-speech temporal contrast (spectrally rotated /ba/-/da/), and (4) a non-speech non-temporal contrast (spectrally rotated /u/-/y/). This design was first applied in an adult sample of 31 normal and 31 dyslexic readers (manuscript 1), and later in a 11-year old sample of 25 normal and 13 dyslexic readers (manuscript 2). In both studies, dyslexic readers demonstrate a specific deficit in the /bA/-/dA/ and rotated /bA/-/dA/-condition, which indicates a deficit in processing rapidly changing auditory information which is not speech-specific. At the neural level, it might be that these temporal specific processing problems are rooted in a decreased myelination, since this is crucial for a fast transmission of action potentials. Diffusion Tensor Imaging (DTI) provides a unique tool to non-invasively measure white matter properties, reflecting indirectly the degree of myelination. In addition, DTI also enables a 3D-reconstruction of white matter connections which is of particular interest to reading since this involves a widespread network of distant brain regions. The most consistent finding across previous DTI studies is that white matter integrity in the left temporoparietal region relates to reading and is decreased in dyslexic readers (review and meta-analysis in manuscript 3). However, evidence is sparse on which white matter bundle corresponds to this and how it relates to reading underlying subskills. We therefore conducted a DTI-study in the 20 best normal reading and 20 poorest dyslexic reading adults of manuscript 1 to investigate specific white matter tracts in relation to phonological and orthographic processing (manuscript 4). Results indicate that dyslexic adults show a lower white matter integrity in the left dorsal arcuate fasciculus, which correlates with phonological processes, whereas no deficit is observed in the left ventral inferior-fronto-occipital-fasciculus, which relates to orthographic aspects of reading. Finally, in manuscript 5 we focus on white matter correlates of auditory temporal processing by linking the DTI-data to neurofunctional EEG-coherence measures of slow (i.e. 4Hz) and fast (i.e. 20Hz) modulations. Dyslexic readers display relative to normal readers a lower neurofunctional coherence for 20 Hz modulations as well as a decreased left lateralization of white matter integrity in the arcuate fasiculus and in the posterior part of the superior temporal gyrus. Interestingly, left lateralization in the latter white matter region correlates in typical readers with better coherence on the fast modulation (20 Hz) whereas this relation was opposite in dyslexic readers. To conclude, at the cognitive level our dyslexic participants displayed specific problems in processing rapidly changing auditory information, which might correspond at the neural level to a decreased left dominance of white matter integrity in the auditory and language regions. The well known phonological problems of dyslexic readers seem to be reflected in a lower white matter integrity of the left arcuate fasciculus, whereas the inferior-fronto-occipital-fasciculus, involved in orthographic processing, is intact in dyslexic adults.status: publishe

Verbeteren van de voorspelling van taalherstel door de inclusie van risico- en beschermende neurocognitieve factoren

Het WAP-thema van dit jaar is Taal en het Brein. Ook het WAP-symposium begin 2020 zal volledig in dit thema staan. Hoe wordt taal verworven en verwerkt door de hersenen? Hoe werkt het tweetalige brein? Wat weten we over taalstoornissen en het brein? Onderzoeksmethoden en therapieën op dit gebied ontwikkelen zich razendsnel. In het symposium zal breed worden gekeken naar het thema: er zullen lezingen zijn over Taal en het Brein bij baby’s tot aan ouderen, en er zal er aandacht zijn voor zowel de klinische als de theoretische kant van het verhaal.Invited lecture, invited by: WAP - Werkvereband Amsterdamse Psycholinguïstenstatus: Published onlin