scholarly journals Effects of a Phonological Intervention on EEG Connectivity Dynamics in Dyslexic Children

2021 ◽  
Author(s):  
Nicolas Bedo ◽  
Dikla Ender-Fox ◽  
Janet Chow ◽  
Linda Siegel ◽  
Urs Ribary ◽  
...  
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Word Reading ◽  
Letter Recognition ◽  
Oscillatory Dynamics ◽  
Before And After ◽  
Eeg Connectivity ◽  
Eeg Recordings ◽  
The Right ◽  
Language Areas

We examined the brain networks and oscillatory dynamics, inferred from EEG recordings during a word-reading task, of a group of children in grades 4 and 5 (ages 9–11), some of whom were dyslexic. We did this in order to characterize the differences in these dynamics between typical and dyslexic readers, and to begin to characterize the effect of a phonological intervention on those differences. Dyslexic readers were recorded both before and after they participated in a FastForWord (FFW) reading training program for approximately six months and typical readers were recorded once during this period. Before FFW dyslexic readers showed (i) a bottleneck in letter recognition areas, (ii) expansion in activity and connectivity into the right hemisphere not seen in typical readers, and (iii) greater engagement of higher-level language areas, even for consonant string stimuli. After FFW, dyslexic readers evinced a significant reduction in the engagement of language processing areas, and more activity and connectivity expanding to frontal areas, more resembling typical readers. Reduction of connectivity was negatively correlated with gains in reading performance, suggesting an increase in communication efficiency. Training appeared to improve the efficiency of the alternative (bilateral) pathways already used by the dyslexic readers, rather than inducing them to create new pathways more similar to those employed by typical readers.

scholarly journals Word learning and the cerebral hemispheres: from serial to parallel processing of written words

2009 ◽  
Vol 364 (1536) ◽  
pp. 3675-3696 ◽  
Author(s):  
Andrew W. Ellis ◽  
Roberto Ferreira ◽  
Polly Cathles-Hagan ◽  
Kathryn Holt ◽  
Lisa Jarvis ◽  
...  
Keyword(s):  
Parallel Processing ◽  
Visual Field ◽  
Word Learning ◽  
Word Reading ◽  
Visual Fields ◽  
Letter Recognition ◽  
Right Visual Field ◽  
Before And After ◽  
Word Forms ◽  
The Right

Reading familiar words differs from reading unfamiliar non-words in two ways. First, word reading is faster and more accurate than reading of unfamiliar non-words. Second, effects of letter length are reduced for words, particularly when they are presented in the right visual field in familiar formats. Two experiments are reported in which right-handed participants read aloud non-words presented briefly in their left and right visual fields before and after training on those items. The non-words were interleaved with familiar words in the naming tests. Before training, naming was slow and error prone, with marked effects of length in both visual fields. After training, fewer errors were made, naming was faster, and the effect of length was much reduced in the right visual field compared with the left. We propose that word learning creates orthographic word forms in the mid-fusiform gyrus of the left cerebral hemisphere. Those word forms allow words to access their phonological and semantic representations on a lexical basis. But orthographic word forms also interact with more posterior letter recognition systems in the middle/inferior occipital gyri, inducing more parallel processing of right visual field words than is possible for any left visual field stimulus, or for unfamiliar non-words presented in the right visual field.

Modes of Lexical Access in the Callosotomized Brain

1992 ◽  
Vol 4 (2) ◽  
pp. 155-164 ◽  
Author(s):  
Patricia A. Reuter-Lorenz ◽  
Kathleen Baynes
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Word Reading ◽  
Letter Recognition ◽  
Superiority Effect ◽  
Decision Performance ◽  
Reading Abilities ◽  
Access Mode ◽  
The Right ◽  
Encoding Strategy

Left hemisphere processing is typically characterized as analytic and serial whereas the right hemisphere is characterized as wholistic and parallel. Word recognition may be an exception to this dichotomy if the letter-by-letter alexia produced by left hemisphere damage reflects the reading abilities of the right hemisphere. We investigated this possibility by studying prelexical and lexical processes in the separated hemispheres of callosotomy patient J. W. A word superiority effect demonstrated in each visual field suggests that both hemispheres have access to a visual lexicon. Error patterns, letter recognition thresholds, and lexical decision performance as a function of word length suggest that the left hemisphere tends to utilize a parallel access mode, whereas the right hemisphere mode is less efficient and may be serial. Furthermore, only J. W.'s left hemisphere showed letter priming, an outcome consistent with observations in letter-by-letter alexia. These findings suggest that the right hemisphere may have an independent visual lexicon and may provide an alternative although less efficient route to reading. We suggest that a serial encoding strategy results because the global processing mode for which the right hemisphere is specialized is largely ineffective for word reading.

The Structural Language Network

2017 ◽  
Author(s):  
Angela D. Friederici ◽  
Noam Chomsky
Keyword(s):  
White Matter ◽  
Language Processing ◽  
Sentence Processing ◽  
Information Transfer ◽  
Right Hemisphere ◽  
Brain Regions ◽  
Neural Basis ◽  
Fiber Tracts ◽  
White Matter Fiber Tracts ◽  
The Right

An adequate description of the neural basis of language processing must consider the entire network both with respect to its structural white matter connections and the functional connectivities between the different brain regions as the information has to be sent between different language-related regions distributed across the temporal and frontal cortex. This chapter discusses the white matter fiber bundles that connect the language-relevant regions. The chapter is broken into three sections. In the first, we look at the white matter fiber tracts connecting the language-relevant regions in the frontal and temporal cortices; in the second, the ventral and dorsal pathways in the right hemisphere that connect temporal and frontal regions; and finally in the third, the two syntax-relevant and (at least) one semantic-relevant neuroanatomically-defined networks that sentence processing is based on. From this discussion, it becomes clear that online language processing requires information transfer via the long-range white matter fiber pathways that connect the language-relevant brain regions within each hemisphere and between hemispheres.

Bihemispheric Language: How the Two Hemispheres Collaborate in the Processing of Language

2004 ◽  
Author(s):  
Norman D. Cook
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Central Question ◽  
Linguistic Processing ◽  
Figures Of Speech ◽  
Language Functions ◽  
Left And Right ◽  
Level Of Understanding ◽  
The Right

Speech production in most people is strongly lateralized to the left hemisphere (LH), but language understanding is generally a bilateral activity. At every level of linguistic processing that has been investigated experimentally, the right hemisphere (RH) has been found to make characteristic contributions, from the processing of the affective aspects of intonation, through the appreciation of word connotations, the decoding of the meaning of metaphors and figures of speech, to the understanding of the overall coherency of verbal humour, paragraphs and short stories. If both hemispheres are indeed engaged in linguistic decoding and both processes are required to achieve a normal level of understanding, a central question concerns how the separate language functions on the left and right are integrated. This chapter reviews relevant studies on the hemispheric contributions to language processing and the role of interhemispheric communications in cognition.

Electrophysiological Measures of Language Processing in Bilinguals

2002 ◽  
Vol 14 (7) ◽  
pp. 994-1017 ◽  
Author(s):  
Alice Mado Proverbio ◽  
Barbara Čok ◽  
Alberto Zani
Keyword(s):  
Language Learners ◽  
Left Hemisphere ◽  
Language Processing ◽  
Right Hemisphere ◽  
Functional Organization ◽  
Brain Plasticity ◽  
Brain Activation ◽  
Activation Patterns ◽  
Bilingual Speakers ◽  
The Right

The aim of the present study was to investigate how multiple languages are represented in the human brain. Event-related brain potentials (ERPs) were recorded from right-handed polyglots and monolinguals during a task involving silent reading. The participants in the experiment were nine Italian monolinguals and nine Italian/Slovenian bilinguals of a Slovenian minority in Trieste; the bilinguals, highly fluent in both languages, had spoken both languages since birth. The stimuli were terminal words that would correctly complete a short, meaningful, previously shown sentence, or else were semantically or syntactically incorrect. The task consisted in deciding whether the sentences were well formed or not, giving the response by pressing a button. Both groups read the same set of 200 Italian sentences to compare the linguistic processing, while the bilinguals also received a set of 200 Slovenian sentences, comparable in complexity and length, to compare the processing of the two languages within the group. For the bilinguals, the ERP results revealed a strong, left-sided activation, reflected by the N1 component, of the occipito-temporal regions dedicated to orthographic processing, with a latency of about 150 msec for Slovenian words, but bilateral activation of the same areas for Italian words, which was also displayed by topographical mapping. In monolinguals, semantic error produced a long-lasting negative response (N2 and N4) that was greater over the right hemisphere, whereas syntactic error activated mostly the left hemisphere. Conversely, in the bilinguals, semantic incongruence resulted in greater response over the left hemisphere than over the right. In this group, the P615 syntactical error responses were of equal amplitude on both hemispheres for Italian words and greater on the right side for Slovenian words. The present findings support the view that there are inter- and intrahemispheric brain activation asymmetries when monolingual and bilingual speakers comprehend written language. The fact that the bilingual speakers in the present study were highly fluent and had acquired both languages in early infancy suggests that the brain activation patterns do not depend on the age of acquisition or the fluency level, as in the case of late, not-so-proficient L2 language learners, but on the functional organization of the bilinguals' brain due to polyglotism and based on brain plasticity.

Lateralised semantic and indirect semantic priming effects in people with schizophrenia

1998 ◽  
Vol 172 (2) ◽  
pp. 142-146 ◽  
Author(s):  
Matthias Weisbrod ◽  
Sabine Maier ◽  
Sabine Harig ◽  
Ulrike Himmelsbach ◽  
Manfred Spitzer
Keyword(s):  
Left Hemisphere ◽  
Semantic Priming ◽  
Language Processing ◽  
Semantic Processing ◽  
Right Hemisphere ◽  
Contextual Information ◽  
Striking Difference ◽  
Semantic Associations ◽  
The Right

BackgroundIn schizophrenia, disturbances in the development of physiological hemisphere asymmetry are assumed to play a pathogenetic role. The most striking difference between hemispheres is in language processing. The left hemisphere is superior in the use of syntactic or semantic information, whereas the right hemisphere uses contextual information more effectively.MethodUsing psycholinguistic experimental techniques, semantic associations were examined in 38 control subjects, 24 non-thought-disordered and 16 thought-disordered people with schizophrenia, for both hemispheres separately.ResultsDirect semantic priming did not differ between the hemispheres in any of the groups. Only thought-disordered people showed significant indirect semantic priming in the left hemisphere.ConclusionsThe results support: (a) a prominent role of the right hemisphere for remote associations; (b) enhanced spreading of semantic associations in thought-disordered subjects; and (c) disorganisation of the functional asymmetry of semantic processing in thought-disordered subjects.

Sites and parasites of meaning: Browning’s ‘My Last Duchess’

2006 ◽  
Vol 15 (2) ◽  
pp. 123-140
Author(s):  
Robin Melrose
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Speech Act ◽  
Systemic Functional Linguistics ◽  
Linguistic Analysis ◽  
Speech Act Theory ◽  
Functional Linguistics ◽  
The Right

Robert Browning’s so-called dramatic lyric ‘My Last Duchess’ has been interpreted differently by different critics, some seeing the Duke as shrewd and others seeing him as witless. This article attempts to account for these differing interpretations by analysing indeterminacies in the language of the poem. Starting out with the work of Derrida on speech act theory, and findings on the role of the right hemisphere in language processing, it goes on to propose techniques of linguistic analysis based on systemic-functional linguistics and the concept of particle-waves of language first discussed in Melrose (1996). The article then analyses a number of these so-called particle-waves in ‘My Last Duchess’, and concludes that opposing interpretations of the Duke can be traced to the indeterminacies of language in the particle-waves.

scholarly journals Virtual reality-based sensorimotor adaptation shapes subsequent spontaneous and naturalistic stimulus-driven brain activity

2021 ◽  
Author(s):  
Meytal Wilf ◽  
Celine Dupuis ◽  
Davide Nardo ◽  
Diana Huber ◽  
Sibilla Sander ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Large Scale ◽  
Right Hemisphere ◽  
Functional Neuroimaging ◽  
Brain Activity ◽  
Visual Response ◽  
Spatial Shift ◽  
Before And After ◽  
Behavioural Tests ◽  
The Right

Our everyday life summons numerous novel sensorimotor experiences, to which our brain needs to adapt in order to function properly. However, tracking plasticity of naturalistic behaviour and associated brain modulations is challenging. Here we tackled this question implementing a prism adaptation training in virtual reality (VRPA) in combination with functional neuroimaging. Three groups of healthy participants (N=45) underwent VRPA (with a spatial shift either to the left/right side, or with no shift), and performed fMRI sessions before and after training. To capture modulations in free-flowing, task-free brain activity, the fMRI sessions included resting state and free viewing of naturalistic videos. We found significant decreases in spontaneous functional connectivity between large-scale cortical networks, namely attentional and default mode/fronto-parietal networks, only for adaptation groups. Additionally, VRPA was found to bias visual representations of naturalistic videos, as following rightward adaptation, we found upregulation of visual response in an area in the parieto-occipital sulcus (POS) in the right hemisphere. Notably, the extent of POS upregulation correlated with the size of the VRPA induced after-effect measured in behavioural tests. This study demonstrates that a brief VRPA exposure is able to change large-scale cortical connectivity and correspondingly bias the representation of naturalistic sensory inputs.

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