Lukács, &. 1, 2 , Dobó, D. 1, 2 , Németh, K. 1 , Szollosi, &. 1, 3 & Lukics, K. S. 1, 2
1 Department of Cognitive Science, Budapest University of Technology and Economics
2 MTA-BME Lendület Language Acquisition Research Group, Budapest, Hungary
3 Institute of Cognitive Neuroscience and Psychology, Hungarian Academy of Sciences
The vulnerability of statistical learning (SL) has been demonstrated in dyslexia in both the visual and acoustic domains. Since investigations so far focused mainly on explicit measures, little is known about the more specific nature and timing of the deficit. We explored segmentation abilities in the acoustic verbal and visual nonverbal domain in online target detection tasks, where the extent of learning is reflected in the differences between reaction times (RT) to predictable versus unpredictable targets. Explicit judgments of well-formedness were also elicited in a 2AFC task. We examined adolescents with and without dyslexia (DD and TD; n=19 in both groups) matched on age, sex and IQ at the group level. A significant online learning effect was observed in both groups in both domains, but participants with dyslexia showed a smaller learning effect and slower learning of statistical regularities. On the explicit measures, the DD group was at chance in the visual, but not the verbal domain. These findings suggest that the SL impairment in dyslexia is present across modalities and domains. Results also imply that explicit measures may mask learning abilities, and measuring learning online can provide more sensitive indices that offer a deeper understanding of the deficit.