Search Abstracts | Symposia | Slide Sessions | Poster Sessions
School-aged children with dyslexia showed disrupted adaptation to words in temporal and frontal - but not visual - language network
Poster Session B, Friday, October 25, 10:00 - 11:30 am, Great Hall 3 and 4
Marek Wypych1, Marta Wójcik2, Katarzyna Jednoróg2, Agnieszka Dębska2; 1Laboratory of Brain Imaging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 2Laboratory of Language Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences
Reading impairments in dyslexia may result from disrupted neural rapid adaptation in language-specialized brain regions upon repeated stimulus presentation (Glezer et al., 2019). In adults with dyslexia the disrupted adaptation to phonological properties was shown in the left temporoparietal cortex (TPC) but not in higher-level visual area (VOT, Glezer, 2019). However other studies on adults and children with dyslexia showed disrupted adaptation in both orthographic and auditory domains (der Mark et al., 2009, Gertsovski & Ahissar, 2022) also regardless of the stimuli’s properties (linguistic or non-linguistic), which would suggest a general neural adaptation deficit in dyslexia (Perrachione et al., 2016). Our study aimed to examine adaptation patterns for orthographic and phonological processing in children with dyslexia (DYS; n = 34) in comparison to typical readers (CON; n = 43) aged 9.7 to 13.18 years. Groups did not significantly differ in sex, age, non-verbal IQ and a socio-economic status. In the fMRI Rapid Adaptation task we repeatedly presented words that shared phonology but differ in orthography (HOMOPHONES, e.g., “pear” – “pair”), shared both (SAME, e.g., “pear” – “pear”) or differed in both (OTHER, e.g., “pear” – “game”). Additionally, an oddball task was created for attention control: children were asked to press the button every time they saw a word containing “TA” syllable in any position of the word. We localized region of interests within the left VOT and TPC individually for each participant using a functional localizer task with visual (words, consonants, false fonts) and auditory tasks (words, consonants, words played backwards). Results in the attentional oddball task did not show CON-DYS differences (CON (M = 84%) and DYS (M = 82%)). Region of interest analyses test with linear mixed models revealed disrupted general adaptation for words (OTHER - SAME) in the left temporal area (TPC) in DYS compared to CON, while adaptation in a higher-level visual region (VOT) remained intact in both groups. Whole-brain analysis identified higher activations in CON than DYS in the left inferior frontal gyrus for orthographic processing (HOMOPHONE - SAME), with no whole-brain differences for phonological-specific processing (OTHER - HOMOPHONE). Overall, our findings confirm that school-aged children with dyslexia exhibit disruptions in neural word adaptation within language-related areas of temporal cortices for phonological and multimodal processing and frontal cortices for orthographic processing, while unexpectedly maintaining preserved adaptation to word forms in higher-level visual areas. Our results are partly in line with the study on adults with dyslexia (Glezer, et al., 2019) but in contrast to studies showing a general adaptation deficit in dyslexia (Perrachione et al., 2016).
Topic Areas: Disorders: Developmental,