Morphological segmenting in reading-impaired children: An ERP study
| dc.contributor.author | Madziak, Rebecca | |
| dc.contributor.examiningcommittee | Russell, Kevin (Linguistics) | en_US |
| dc.contributor.examiningcommittee | Desroches, Amy (University of Winnipeg) | en_US |
| dc.contributor.supervisor | Kruk, Richard (Psychology) | en_US |
| dc.date.accessioned | 2020-09-08T19:44:32Z | |
| dc.date.available | 2020-09-08T19:44:32Z | |
| dc.date.copyright | 2020-09-06 | |
| dc.date.issued | 2020-07-31 | en_US |
| dc.date.submitted | 2020-09-06T22:14:32Z | en_US |
| dc.degree.discipline | Psychology | en_US |
| dc.degree.level | Master of Arts (M.A.) | en_US |
| dc.description.abstract | Rapidly parsing complex words into their morphological components can facilitate word recognition. This process is semantically blind in its early stages: adult typical readers experience facilitation in primed lexical decision tasks with both morphological primes that include semantic and orthographic information, and pseudo-suffixed primes that include only orthographic information (e.g., corner- CORN). However, reading-impaired (RI) children show facilitation with complex morphological primes only (e.g., worker- WORK), indicating benefits of semantic (and not orthographic) information in word recognition. The current study tested whether neural and behavioural patterns in RI children were consistent with facilitation of word recognition via semantic information only. Early temporal dynamics of word recognition in 10 RI children in Grades 5 and 6, 16 chronological-age typical-reader controls (CA), and 12 reading-age controls in Grade 2 (RA) were examined using event related potentials (ERPs) recorded during a primed lexical decision task. A reduced N400 ERP component (a negative spike in electrical voltage occurring approximately 400ms after target onset) indicates facilitation in lexical access, with smaller negative amplitude corresponding to lower cognitive load with related primes compared to unrelated primes. Results showed the expected reduction in N400 in CAs: facilitation with morphological and pseudo-suffixed primes relative to unrelated primes. As well, stronger amplitude reduction was found for morphological related primes compared to pseudo-suffixed related primes. CAs also experienced an N250 reduction in response to related primes, indicating sensitivity to orthographic overlap. N400 patterns for RIs showed, unexpectedly, priming effects in both related suffix-type conditions. RAs did not show priming in their ERP patterns, likely a result of slow and laborious serial letter processing inhibiting benefits from the brief prime display. The results have implications for understanding the roles of orthographic and morphological information in word identification in children with and without reading impairment and for general theories of morphological processing. | en_US |
| dc.description.note | October 2020 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/34992 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Reading-impaired | en_US |
| dc.subject | Dual-route model | en_US |
| dc.subject | Morpho-semantic | en_US |
| dc.subject | Morpho-orthographic | en_US |
| dc.subject | N400 | en_US |
| dc.subject | N250 | en_US |
| dc.subject | Lexical decision | en_US |
| dc.title | Morphological segmenting in reading-impaired children: An ERP study | en_US |
| dc.type | master thesis | en_US |