Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia
Skilled reading requires specialized visual cortical processing of orthographic information and its impairment has been proposed as a potential correlate of compromised reading in dyslexia. However, which stage of orthographic information processing during natural reading is disturbed in dyslexics r...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2022-09-01
|
| Series: | NeuroImage |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S105381192200502X |
| _version_ | 1817977306130415616 |
|---|---|
| author | Béla Weiss Ádám Nárai Zoltán Vidnyánszky |
| author_facet | Béla Weiss Ádám Nárai Zoltán Vidnyánszky |
| author_sort | Béla Weiss |
| collection | DOAJ |
| description | Skilled reading requires specialized visual cortical processing of orthographic information and its impairment has been proposed as a potential correlate of compromised reading in dyslexia. However, which stage of orthographic information processing during natural reading is disturbed in dyslexics remains unexplored. Here we addressed this question by simultaneously measuring the eye movements and EEG of dyslexic and control young adults during natural reading. Isolated meaningful sentences were presented at five inter-letter spacing levels spanning the range from minimal to extra-large spacing, and participants were instructed to read the text silently at their own pace. Control participants read faster, performed larger saccades and shorter fixations compared to dyslexics. While reading speed peaked around the default letter spacing, saccade amplitude increased and fixation duration decreased with the increase of letter spacing in both groups. Lateralization of occipito-temporal fixation-related EEG activity (FREA) was found in three consecutive time intervals corresponding to early orthographic processing in control readers. Importantly, the lateralization in the time range of the first negative left occipito-temporal FREA peak was specific for first fixations and exhibited an interaction effect between reading ability and letter spacing. The interaction originated in the significant decrease of FREA lateralization at extra-large compared to default letter spacing in control readers and the lack of lateralization in both letter spacing conditions in the case of dyslexics. These findings suggest that expertise-driven hemispheric functional specialization for early orthographic processing thought to be responsible for letter identity extraction during natural reading is compromised in dyslexia. |
| first_indexed | 2024-04-13T22:14:31Z |
| format | Article |
| id | doaj.art-547a2189fc674c3bbb7b5abaef3ce850 |
| institution | Directory Open Access Journal |
| issn | 1095-9572 |
| language | English |
| last_indexed | 2024-04-13T22:14:31Z |
| publishDate | 2022-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | NeuroImage |
| spelling | doaj.art-547a2189fc674c3bbb7b5abaef3ce8502022-12-22T02:27:36ZengElsevierNeuroImage1095-95722022-09-01258119383Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexiaBéla Weiss0Ádám Nárai1Zoltán Vidnyánszky2Corresponding authors.; Brain Imaging Centre, Research Centre for Natural Sciences, Magyar tudósok körútja 2., Budapest H-1117, HungaryBrain Imaging Centre, Research Centre for Natural Sciences, Magyar tudósok körútja 2., Budapest H-1117, HungaryCorresponding authors.; Brain Imaging Centre, Research Centre for Natural Sciences, Magyar tudósok körútja 2., Budapest H-1117, HungarySkilled reading requires specialized visual cortical processing of orthographic information and its impairment has been proposed as a potential correlate of compromised reading in dyslexia. However, which stage of orthographic information processing during natural reading is disturbed in dyslexics remains unexplored. Here we addressed this question by simultaneously measuring the eye movements and EEG of dyslexic and control young adults during natural reading. Isolated meaningful sentences were presented at five inter-letter spacing levels spanning the range from minimal to extra-large spacing, and participants were instructed to read the text silently at their own pace. Control participants read faster, performed larger saccades and shorter fixations compared to dyslexics. While reading speed peaked around the default letter spacing, saccade amplitude increased and fixation duration decreased with the increase of letter spacing in both groups. Lateralization of occipito-temporal fixation-related EEG activity (FREA) was found in three consecutive time intervals corresponding to early orthographic processing in control readers. Importantly, the lateralization in the time range of the first negative left occipito-temporal FREA peak was specific for first fixations and exhibited an interaction effect between reading ability and letter spacing. The interaction originated in the significant decrease of FREA lateralization at extra-large compared to default letter spacing in control readers and the lack of lateralization in both letter spacing conditions in the case of dyslexics. These findings suggest that expertise-driven hemispheric functional specialization for early orthographic processing thought to be responsible for letter identity extraction during natural reading is compromised in dyslexia.http://www.sciencedirect.com/science/article/pii/S105381192200502XNatural readingEye trackingFixation-related EEG activityLateralizationInter-letter spacingDevelopmental dyslexia |
| spellingShingle | Béla Weiss Ádám Nárai Zoltán Vidnyánszky Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia NeuroImage Natural reading Eye tracking Fixation-related EEG activity Lateralization Inter-letter spacing Developmental dyslexia |
| title | Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| title_full | Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| title_fullStr | Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| title_full_unstemmed | Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| title_short | Lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| title_sort | lateralization of early orthographic processing during natural reading is impaired in developmental dyslexia |
| topic | Natural reading Eye tracking Fixation-related EEG activity Lateralization Inter-letter spacing Developmental dyslexia |
| url | http://www.sciencedirect.com/science/article/pii/S105381192200502X |
| work_keys_str_mv | AT belaweiss lateralizationofearlyorthographicprocessingduringnaturalreadingisimpairedindevelopmentaldyslexia AT adamnarai lateralizationofearlyorthographicprocessingduringnaturalreadingisimpairedindevelopmentaldyslexia AT zoltanvidnyanszky lateralizationofearlyorthographicprocessingduringnaturalreadingisimpairedindevelopmentaldyslexia |