Figure - available from: Frontiers in Human Neuroscience
This content is subject to copyright.
Linear derivations over the electrodes where the P3b was maximal for typical and dyslexic readers’ responses in correct trials (Gray bar: analysis window). (A) Visual-orthographic deviants; (B) Phonological deviants.
Source publication
New evidence is accumulating for a deficit in binding visual-orthographic information with the corresponding phonological code in developmental dyslexia. Here, we identify the mechanisms underpinning this deficit using event-related brain potentials (ERPs) in dyslexic and control adult readers performing a letter-matching task. In each trial, a pri...
Similar publications
Automatic visual word recognition requires not only well-established phonological and orthographic representations but also efficient audio-visual integration of these representations. One possibility is that in developmental dyslexia, inefficient orthographic processing might underlie poor reading. Alternatively, reading deficit could be due to in...
Phonological difficulties have been identified as a core deficit in developmental dyslexia, yet everyday speech comprehension, which relies on phonological processing, is seemingly unaffected. This raises the question as to how dyslexic readers process spoken words to achieve normal word comprehension. Here we establish a link between neural correl...
Skilled reading requires years of practice to learn to associate visual symbols (graphemes) with speech sounds (phonemes). Over the course of the learning process, this association becomes almost effortless and automatic. Here we hypothesize that automatic activation of phonological processing circuits in response to a visually presented word is a...
Dyslexia is targeted most effectively when (1) interventions are provided preventively, before the onset of reading instruction, and (2) remediation programs combine letter-sound training with phoneme blending. Given the growing potential of technology in educational contexts, there has been a considerable increase of letter-sound trainings embedde...
When children learn to read, their neural system undergoes major changes to become responsive to print. There seem to be nuanced interindividual differences in the neurostructural anatomy of regions that later become integral parts of the reading network. These differences might affect literacy acquisition and, in some cases, might result in develo...
Citations
... In research, EEG can be used to measure specific patterns of electrical activity associated with sensory, motor, affective, and cognitive events, to track brain development and maturation, and to describe brain-behavior relations (e.g. Beres, 2017;Carbine et al., 2018;Clayson et al., 2021;Jones et al., 2016;Remijn et al., 2014;Kaiser et al., 2020). ...
... In research, EEG can be used to measure specific patterns of electrical activity associated with sensory, motor, affective, and cognitive events, to track brain development and maturation, and to describe brain-behaviour relations (e.g. Beres, 2017;Carbine et al., 2018;Clayson et al., 2021;Jones et al., 2016;Remijn et al., 2014, Kaiser et al., 2020. ...
Electroencephalography (EEG) is an important tool in the field of developmental cognitive neuroscience for indexing neural activity. However, racial biases persist in EEG research that limit the utility of this tool. One bias comes from the structure of EEG nets/caps that do not facilitate equitable data collection across hair textures and types. Recent efforts have improved EEG net/cap design, but these solutions can be time-intensive, reduce sensor density, and are more difficult to implement in younger populations. The present study focused on testing EEG sensor net designs over infancy. Specifically, we compared EEG data quality and retention between two high-density saline-based EEG sensor net designs from the same company (Magstim EGI, Whitland, UK) within the same infants during a baseline EEG paradigm. We found that within infants, the tall sensor nets resulted in lower impedances during collection, including lower impedances in the key online reference electrode for those with greater hair heights and resulted in a greater number of usable EEG channels and data segments retained during pre-processing. These results suggest that along with other best practices, the modified tall sensor net design is useful for improving data quality and retention in infant participants with curly or tightly-coiled hair.
... Interpretations of the findings can be explained from the perspective of the dyslexia automatization deficit hypothesis and the supervisory attentional system rather than merely from the point of view of the phonological deficit hypothesis. Dyslexia is the most frequently occurring developmental condition (e.g., Lyon, 1996;Shaywitz, 1998;Shaywitz & Shaywitz, 2003) with documented occurrences reported as being between 5 and 17% in the Western population (e.g., Badian, 1984;Jones, Kuipers, & Thierry, 2016;Katusic, Colligan, Barbaresi, Schaid, & Jacobsen, 2001;Shaywitz, 1998;Shaywitz, Shaywitz, Fletcher, & Escobar, 1990). This wideranging estimate of incidences is a consequence of the diversity of definitions and diagnostic criteria developed in studying dyslexia (e.g., Elliot & Grigorenko, 2014). ...
Dyslexia-related difficulties have been reported in executive functions, time perception and prospective memory in both children and adults. With evidence of problems in these areas shown to persevere into adulthood, the extent of their presence was investigated in adults with and without dyslexia. Using a wide-range of experimental laboratory-based, semi-naturalistic and naturalistic tasks, prospective memory, executive functions and time perception were investigated in the two groups of university students with and without dyslexia. The two groups were matched for age and IQ and differed on spelling and reading tests. The results indicated prospective memory problems in adults with dyslexia when prospective memory performance relied on time-cues rather than on environmental cues and when time-cues were one-off rather than repetitive. Furthermore, adults with dyslexia showed problems in a range of executive functions related to set-shifting, dual-task performance and planning. There was no evidence of dyslexia-related difficulties in time perception tasks in both short duration (milliseconds range) and long duration (minutes range). The findings in this work point to several dyslexia-related problems that fall within the cognitive functioning range. Interpretations of the findings can be explained from the perspective of the dyslexia automatization deficit hypothesis and the supervisory attentional system rather than merely from the point of view of the phonological deficit hypothesis.
... If the reader uses the initial gaze time on the text ahead of the currently uttered word or syllable, the time can be used to finish the processing of the currently gazed part of the text as well, that is, parallel processing of the two components (or words) in the text can take place at the same time (Jones et al., 2008(Jones et al., , 2016Protopapas et al., 2013;Laubrock and Kliegl, 2015). Additionally, buffering of the material that can be rapidly decoded and translated from graphemic input into a phonological code also allows faster reading through processing of word articulation into chunks. ...
Background
The coordination between gaze and voice is closely linked when reading text aloud, with the gaze leading the reading position by a certain eye–voice lead (EVL). How this coordination is affected is unknown in patients with cerebellar ataxia and parkinsonism, who show oculomotor deficits possibly impacting coordination between different effectors.
Objective
To elucidate the role of the cerebellum and basal ganglia in eye–voice coordination during reading aloud, by studying patients with Parkinson’s disease (PD) and spinocerebellar degeneration (SCD).
Methods
Participants were sixteen SCD patients, 18 PD patients, and 30 age-matched normal subjects, all native Japanese speakers without cognitive impairment. Subjects read aloud Japanese texts of varying readability displayed on a monitor in front of their eyes, consisting of Chinese characters and hiragana (Japanese phonograms). The gaze and voice reading the text was simultaneously recorded by video-oculography and a microphone. A custom program synchronized and aligned the gaze and audio data in time.
Results
Reading speed was significantly reduced in SCD patients (3.53 ± 1.81 letters/s), requiring frequent regressions to compensate for the slow reading speed. In contrast, PD patients read at a comparable speed to normal subjects (4.79 ± 3.13 letters/s vs. 4.71 ± 2.38 letters/s). The gaze scanning speed, excluding regressive saccades, was slower in PD patients (9.64 ± 4.26 letters/s) compared to both normal subjects (12.55 ± 5.42 letters/s) and SCD patients (10.81 ± 4.52 letters/s). PD patients’ gaze could not far exceed that of the reading speed, with smaller allowance for the gaze to proceed ahead of the reading position. Spatial EVL was similar across the three groups for all texts (normal: 2.95 ± 1.17 letters/s, PD: 2.95 ± 1.51 letters/s, SCD: 3.21 ± 1.35 letters/s). The ratio of gaze duration to temporal EVL was lowest for SCD patients (normal: 0.73 ± 0.50, PD: 0.70 ± 0.37, SCD: 0.40 ± 0.15).
Conclusion
Although coordination between voice and eye movements and normal eye-voice span was observed in both PD and SCD, SCD patients made frequent regressions to manage the slowed vocal output, restricting the ability for advance processing of text ahead of the gaze. In contrast, PD patients experience restricted reading speed primarily due to slowed scanning, limiting their maximum reading speed but effectively utilizing advance processing of upcoming text.
... We predicted that, if the PMN occurs inattentively, the inattentive mismatch effect should result in significantly more negative mean amplitudes than for the inattentive match condition, across similar electrodes as compared to those for attentive mismatch effect within the 150 -380 ms time window (i.e., the earliest and latest reported PMN onsets and offsets, see van den Brink, Brown, & Hagoort, 2001;Connolly, Stewart & Phillips, 1990;Connolly, Phillips, Stewart & Brake, 1992;Jachmann, Drenhaus, Staudte, & Crocker, 2019, Jones, Kuipers, Thierry 2016. Alternatively, if generation of the PMN necessitates attention, we would expect no significant difference between inattentive match vs inattentive mismatch conditions. ...
... The attentive PMN of experiment 1 revealed by our cluster analysis is consistent with the latency of a number of prior PMN reports (Praamstra, Meyer, & Levelt, 1994;Jones, Kuipers, Thierry, 2016;D'Arcy et al., 2004), though somewhat extended as compared to studies in which time windows are selected via visual waveform inspection. The effect is, additionally, markedly centro-parietal relative to the typical PMN characterisation as a frontal, or fronto-central effect. ...
The Phonological Mapping Negativity (PMN) is an event-related potential component thought to index pre-lexical phonological processing. The response has long been considered distinct from the temporally-proximate Mismatch Negativity (MMN) – a distinction that primarily rests on the assumption that the PMN, unlike the MMN, cannot be elicited in inattentive contexts, thus implying differing underlying auditory-cortex mechanisms. Despite this, no study to date has established whether elicitation of an inattentive PMN response is possible. Here, we tested this assumption in two experiments during which participants heard phonological mismatches whilst engaging in a distractor task (experiment 1) or watching a film (experiment 2). Our results showed no consistent evidence for an inattentive PMN. Though attention may indeed serve to distinguish the two components, our results highlight consistent discrepancies in the temporal, topographical, and functional characteristics of the PMN that undermine efforts to establish its significance in the electrophysiological timeline of speech processing.
... These studies have found that the neural timewindow of audio-visual integration changes from later to earlier (Froyen et al., 2009;Žarić et al., 2014) and becomes narrower/ more time-sensitive (Žarić et al., 2014) over the course of (reading) development. Moreover, the latency of integrative letter-speech sound responses has been found to deviate in dyslexic compared to typical readers (Froyen et al., 2011;Žarić et al., 2014;Jones et al., 2016;Moll et al., 2016) with a speeding up of these responses after 6 months of intensive letter-speech sound training in dyslexic children (Žarić et al., 2015). Suggestive evidence for a direct influence of visual text on pSTC responses to speech comes from the observation that pSTC activation increases in response to matching (congruent) compared to non-matching (incongruent) letter-speech sound pairs and speech alone (Raij et al., 2000;van Atteveldt et al., 2004;Blau et al., 2010;van Atteveldt and Ansari, 2014;Karipidis et al., 2017). ...
Reading acquisition reorganizes existing brain networks for speech and visual processing to form novel audio-visual language representations. This requires substantial cortical plasticity that is reflected in changes in brain activation and functional as well as structural connectivity between brain areas. The extent to which a child’s brain can accommodate these changes may underlie the high variability in reading outcome in both typical and dyslexic readers. In this review, we focus on reading-induced functional changes of the dorsal speech network in particular and discuss how its reciprocal interactions with the ventral reading network contributes to reading outcome. We discuss how the dynamic and intertwined development of both reading networks may be best captured by approaching reading from a skill learning perspective, using audio-visual learning paradigms and longitudinal designs to follow neuro-behavioral changes while children’s reading skills unfold.
... Most studies that support this hypothesis are concurrent ERP or fMRI studies comparing lettersound processing in small groups of children or adults with dyslexia, to typically developing readers matched for age (Bakos, Landerl, Bartling, Schulte-Körne, & Moll, 2017;Blau et al., 2010;Blau, van Atteveldt, Ekkebus, Goebel, & Blomert, 2009;Jones, Kuipers, & Thierry, 2016;Karipidis et al., 2017;Kronschnabel, Brem, Maurer, & Brandeis, 2014;Moll, Hasko, Groth, Bartling, & Schulte-Körne, 2016). These studies report atypical (or developmentally delayed) associations between letters and speech-sounds in children with dyslexia, but with little agreement between different studies. ...
It is now widely accepted that phonological language skills are a critical foundation for learning to read (decode). This longitudinal study investigated the predictive relationship between a range of key phonological language skills and early reading development in a sample of 191 children in their first year at school. The study also explored the theory that a failure to establish automatic associations between letters and speech sounds is a proximal causal risk factor for difficulties in learning to read. Our findings show that automatic letter-sound associations are established early, but do not predict variations in reading development. In contrast, phoneme awareness, letter-sound knowledge and alphanumeric RAN were all strong independent predictors of reading development. In addition, both phoneme awareness and RAN displayed a reciprocal relationship with reading, such that the growth of reading predicted improvements in these skills.
... Support for a deficit in letter-speech sound integration in dyslexic readers largely comes from studies comparing the processing of congruent versus incongruent letter-speech sound stimuli. Indeed, both behavioral (Snowling, 1980;Blomert and Willems, 2010;Aravena et al., 2013) and brain activity studies (Blau et al., 2009(Blau et al., , 2010Froyen et al., 2011;Žarić et al., 2014Jones et al., 2016;Moll et al., 2016) have shown that children and adults with dyslexia process letter speech sound pairs differently from typical readers (but see Nash et al., 2016;Clayton and Hulme, 2017). In a series of EEG studies in the relatively transparent Dutch orthography, these differences were observed in audio-visual mismatch negativity (MMN) and late negativity (LN) responses at a 100-200 ms and 600-750 ms latency following an audio-visual deviant stimulus in a sequence of standards (Froyen et al., 2009(Froyen et al., , 2011Žarić et al., 2014). ...
One of the proposed mechanisms underlying reading difficulties observed in developmental dyslexia is impaired mapping of visual to auditory speech representations. We investigate these mappings in 20 typically reading and 20 children with dyslexia aged 8–10 years using text-based recalibration. In this paradigm, the pairing of visual text and ambiguous speech sounds shifts (recalibrates) the participant’s perception of the ambiguous speech in subsequent auditory-only post-test trials. Recent research in adults demonstrated this text-induced perceptual shift in typical, but not in dyslexic readers. Our current results instead show significant text-induced recalibration in both typically reading children and children with dyslexia. The strength of this effect was significantly linked to the strength of perceptual adaptation effects in children with dyslexia but not typically reading children. Furthermore, additional analyses in a sample of typically reading children of various reading levels revealed a significant link between recalibration and phoneme categorization. Taken together, our study highlights the importance of considering dynamic developmental changes in reading, letter-speech sound coupling and speech perception when investigating group differences between typical and dyslexic readers.
... In crossmodal adaptations, visual (letter) and auditory (speech sound) stimuli were presented simultaneously. Auditory (Froyen et al., 2008) but not visual (Froyen et al., 2010) MMNs were boosted by simultaneous congruent information, but only in advanced and not beginning readers (Froyen et al., 2009;Jones et al., 2016) and also not in children with dyslexia (Froyen et al., 2011). These results have been integrated, suggesting that automatization of letter-speech sound associations develops with reading proficiency, but not in the case of a reading deficit (Blomert, 2011). ...
Efficient and automatic integration of letters and speech sounds is assumed to enable fluent word recognition and may in turn also underlie the build-up of high-quality orthographic representations, which are relevant for accurate spelling. While previous research showed that developmental dyslexia is associated with deficient letter-speech sound integration, these studies did not differentiate between subcomponents of literacy skills. In order to investigate whether deficient letter-speech sound integration is associated with deficits in reading and/or spelling, three groups of third graders were recruited: (1) children with combined deficits in reading and spelling (RSD, N = 10); (2) children with isolated spelling deficit (ISD, N = 17); and (3) typically developing children (TD, N = 21). We assessed the neural correlates (EEG) of letter-speech sound integration using a Stroop-like interference paradigm: participants had to decide whether two visually presented letters look identical. In case of non-identical letter pairs, conflict items were the same letter in lower and upper case (e.g., “T t”), while non-conflict items were different letters (e.g., “T k”). In terms of behavioral results, each of the three groups exhibited a comparable amount of conflict-related reaction time (RT) increase, which may be a sign for no general inhibitory deficits. Event-related potentials (ERPs), on the other hand, revealed group-based differences: the amplitudes of the centro-parietal conflict slow potential (cSP) were increased for conflicting items in typical readers as well as the ISD group. Preliminary results suggest that this effect was missing for children with RSD. The results suggest that deficits in automatized letter-speech sound associations are associated with reading deficit, but no impairment was observed in spelling deficit.
... Beyond paired-associate learning-reflecting early acquisition processes-visualphonological associations remain impaired in dyslexia, even for highly-overlearned pairings, such as letter-to-letter sound associations (Blau, Van Atteveldt, Ekkebus, Goebel, & Blomert, 2009;Jones, Kuipers, & Thierry, 2016;Žarić et al., 2015). Failure to learn efficiently during the first exposures must therefore have long-term consequences for memory consolidation, despite potentially ameliorating factors such as practice and maturation (Snowling, 2000). ...
... Fluent reading involves automatizing access to visual-phonological associations (Froyen, Bonte, van Atteveldt, & Blomert, 2009;Froyen, Willems & Blomert, 2011;Jones, Kuipers, & Thierry, 2016). Thus, episodic contributions to visual-phonological mappings must gradually decrease as repeated presentations of letter-sound correspondences strengthen implicit pathways for reading (LaBerg and Samuels, 1974;Denckla & Rudel, 1976;Jones, Ashby, & Branigan, 2013;Jones, Obregon, Kelly, & Branigan, 2008). ...
... Whereas previous studies typically reported a single accuracy score for paired associate learning, as a culmination of multiple exposures (e.g., Hulme et al., 2007;Wang et al., 2016;Litt et al., 2013;Litt & Nation, 2014), here we mapped the learning process as it unfolded over a larger number of repetitions, from initial exposure through to trials in which pairs were relatively familiar (15 -18 exposures), thus better approximating the development of the stable visual-phonological bindings that form the basis of successful reading. Verbal recall accuracy data showed that typical readers also improved more quickly over multiple exposures than was the case for dyslexic readers, possibly foreshadowing dyslexic readers' general resistance to developing highly automatized letter-sound correspondences in reading (Froyen et al., 2009(Froyen et al., , 2011Jones et al., 2016). ...
Learning visual-phonological associations is a key skill underlying successful reading acquisition. However, we are yet to understand the cognitive mechanisms that enable efficient learning in good readers, and those which are aberrant in individuals with developmental dyslexia. Here, we use a repeated cued-recall task to examine how typical and reading-impaired adults acquire novel associations between visual and phonological stimuli, incorporating a looking-at-nothing paradigm to probe implicit memory for target locations. Cued recall accuracy revealed that typical readers' recall of novel phonological associates was better than dyslexic readers' recall, and it also improved more with repetition. Eye fixation-contingent error analyses suggest that typical readers' greater improvement from repetition reflects their more robust encoding and/or retrieval of each instance in which a given pair was presented: whereas dyslexic readers tended to recall a phonological target better when fixating its most recent location, typical readers showed this pattern more strongly when the target location was consistent across multiple trials. Thus, typical readers' greater success in reading acquisition may derive from their better use of statistical contingencies to identify consistent stimulus features across multiple exposures. We discuss these findings in relation to the role of implicit memory in forming new visual-phonological associations as a foundational skill in reading, and areas of weakness in developmental dyslexia.
