scholarly journals Beyond the phonological deficit: Semantics contributes indirectly to decoding efficiency in children with dyslexia

Dyslexia ◽  
2018 ◽  
Vol 24 (4) ◽  
pp. 309-321 ◽  
Author(s):  
Robin van Rijthoven ◽  
Tijs Kleemans ◽  
Eliane Segers ◽  
Ludo Verhoeven
2017 ◽  
Vol 60 (3) ◽  
pp. 654-667 ◽  
Author(s):  
Mark R. van den Bunt ◽  
Margriet A. Groen ◽  
Takayuki Ito ◽  
Ana A. Francisco ◽  
Vincent L. Gracco ◽  
...  

Purpose The purpose of this study was to examine whether developmental dyslexia (DD) is characterized by deficiencies in speech sensory and motor feedforward and feedback mechanisms, which are involved in the modulation of phonological representations. Method A total of 42 adult native speakers of Dutch (22 adults with DD; 20 participants who were typically reading controls) were asked to produce /bep/ while the first formant (F1) of the /e/ was not altered (baseline), increased (ramp), held at maximal perturbation (hold), and not altered again (after-effect). The F1 of the produced utterance was measured for each trial and used for statistical analyses. The measured F1s produced during each phase were entered in a linear mixed-effects model. Results Participants with DD adapted more strongly during the ramp phase and returned to baseline to a lesser extent when feedback was back to normal (after-effect phase) when compared with the typically reading group. In this study, a faster deviation from baseline during the ramp phase, a stronger adaptation response during the hold phase, and a slower return to baseline during the after-effect phase were associated with poorer reading and phonological abilities. Conclusion The data of the current study are consistent with the notion that the phonological deficit in DD is associated with a weaker sensorimotor magnet for phonological representations.


Cognition ◽  
2013 ◽  
Vol 127 (2) ◽  
pp. 270-286 ◽  
Author(s):  
Ariel M. Cohen-Goldberg ◽  
Joana Cholin ◽  
Michele Miozzo ◽  
Brenda Rapp
Keyword(s):  

2012 ◽  
Vol 466-467 ◽  
pp. 1100-1103
Author(s):  
Hong Shan Nie ◽  
Qiang Liu ◽  
Miao Li ◽  
Qing Jiang Li ◽  
Hai Jun Liu ◽  
...  

In this paper, a common infrared remote control transmitter is designed, using which, a variety of infrared remote control signal can be decoded, stored and transmitted when users need. And with this design, the problem that remote controllers can not be universally operated is solved . In the design, the algorithm of pattern clustering is used to reduce the errors caused by the instability of clock signal. Moreover, the method of vector Quantization coding and repetitive pattern recognition is used to compress he remote control signal data which achieve a good decoding efficiency and a storage efficiency. Experiments show that the design is feasible and has a good prospect in application.


2021 ◽  
Vol 11 (11) ◽  
pp. 1510
Author(s):  
David L. Share

In this discussion paper, I review a number of common misconceptions about the phonological deficit theory (PDH) of dyslexia. These include the common but mistaken idea that the PDH is simply about phonemic awareness (PA), and, consequently, is a circular “pseudo”-explanation or epiphenomenon of reading difficulties. I argue that PA is only the “tip of the phonological iceberg” and that “deeper” spoken-language phonological impairments among dyslexics appear well before the onset of reading and even at birth. Furthermore, not even reading-specific expressions of phonological deficits—PA or pseudoword naming, can be considered circular if we clearly distinguish between reading proper—real meaning-bearing words, or real text, and the mechanisms (subskills) of reading development (such as phonological recoding). I also explain why an understanding of what constitutes an efficient writing system explains why phonology is necessarily a major source of variability in reading ability and hence a core deficit (or at least one core deficit) among struggling readers whether dyslexic or non-dyslexic. I also address the misguided notion that the PDH has now fallen out of favor because most dyslexia researchers have (largely) ceased studying phonological processing. I emphasize that acceptance of the PDH does not imply repudiation of other non-phonological hypotheses because the PDH does not claim to account for all the variance in reading ability/disability. Finally, I ask where neurobiology enters the picture and suggest that researchers need to exercise more caution in drawing their conclusions.


Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 729
Author(s):  
Bahar Khonsari ◽  
Roland Klassen

Pus1-dependent pseudouridylation occurs in many tRNAs and at multiple positions, yet the functional impact of this modification is incompletely understood. We analyzed the consequences of PUS1 deletion on the essential decoding of CAG (Gln) codons by tRNAGlnCUG in yeast. Synthetic lethality was observed upon combining the modification defect with destabilized variants of tRNAGlnCUG, pointing to a severe CAG-decoding defect of the hypomodified tRNA. In addition, we demonstrated that misreading of UAG stop codons by a tRNAGlnCUG variant is positively affected by Pus1. Genetic approaches further indicated that mildly elevated temperature decreases the decoding efficiency of CAG and UAG via destabilized tRNAGlnCAG variants. We also determined the misreading of CGC (Arg) codons by tRNAHisGUG, where the CGC decoder tRNAArgICG contains Pus1-dependent pseudouridine, but not the mistranslating tRNAHis. We found that the absence of Pus1 increased CGC misreading by tRNAHis, demonstrating a positive role of the modification in the competition against non-synonymous near-cognate tRNA. Part of the in vivo decoding defects and phenotypes in pus1 mutants and strains carrying destabilized tRNAGlnCAG were suppressible by additional deletion of the rapid tRNA decay (RTD)-relevant MET22, suggesting the involvement of RTD-mediated tRNA destabilization.


2020 ◽  
Vol 66 (6) ◽  
pp. 1053-1057
Author(s):  
Roland Klassen ◽  
Alexander Bruch ◽  
Raffael Schaffrath

Abstract Posttranscriptional modifications of anticodon loops contribute to the decoding efficiency of tRNAs by supporting codon recognition and loop stability. Consistently, strong synthetic growth defects are observed in yeast strains simultaneously lacking distinct anticodon loop modifications. These phenotypes are accompanied by translational inefficiency of certain mRNAs and disturbed protein homeostasis resulting in accumulation of protein aggregates. Different combinations of anticodon loop modification defects were shown to affect distinct tRNAs but provoke common transcriptional changes that are reminiscent of the cellular response to nutrient starvation. Multiple mechanisms may be involved in mediating inadequate starvation response upon loss of critical tRNA modifications. Recent evidence suggests protein aggregate induction to represent one such trigger.


Science ◽  
2020 ◽  
Vol 368 (6488) ◽  
pp. eaay6912 ◽  
Author(s):  
Robert Buschauer ◽  
Yoshitaka Matsuo ◽  
Takato Sugiyama ◽  
Ying-Hsin Chen ◽  
Najwa Alhusaini ◽  
...  

Control of messenger RNA (mRNA) decay rate is intimately connected to translation elongation, but the spatial coordination of these events is poorly understood. The Ccr4-Not complex initiates mRNA decay through deadenylation and activation of decapping. We used a combination of cryo–electron microscopy, ribosome profiling, and mRNA stability assays to examine the recruitment of Ccr4-Not to the ribosome via specific interaction of the Not5 subunit with the ribosomal E-site in Saccharomyces cerevisiae. This interaction occurred when the ribosome lacked accommodated A-site transfer RNA, indicative of low codon optimality. Loss of the interaction resulted in the inability of the mRNA degradation machinery to sense codon optimality. Our findings elucidate a physical link between the Ccr4-Not complex and the ribosome and provide mechanistic insight into the coupling of decoding efficiency with mRNA stability.


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