Poster B52, Sunday, March 25, 8:00-10:00 am, Exhibit Hall C
University students with a history of reading difficulty show reduced neural effects of word expectancy
Suzanne Welcome1; 1University of Missouri - St Louis
It is known that some individuals identified as having severe reading problems in childhood have no apparent reading comprehension deficits in adulthood. What is not fully understood is how individuals with compensated dyslexia read. One possible compensatory mechanism is greater reliance on meaningful relationships between words. We used event-related potential (ERP) data to explore the idea that individuals with a history of reading difficulty make more use of sentence context to support word identification. University students with and without a self-reported history of reading difficulty completed a battery of standardized tests of reading and read a series of strongly or weakly constraining sentences ending in expected or unexpected words. We compared amplitude differences in the N400 (275-450 ms post stimulus onset) between expected and unexpected sentence-final words. Individuals with a history of reading difficulty showed smaller expectancy effects in the N400 window than their peers without such a history over parietal sites, particularly for weakly constraining sentence frames. Further, scores on the self-report measure of reading difficulty were significantly associated with the magnitude of expectancy effects across the whole sample of university students. Contrary to the prediction that individuals with a history of reading difficulty would show stronger effects of expectancy as a result of more reliance on meaningful relationships between words, individuals with a history of reading difficulty showed less difference between expected and unexpected sentence-final words. However, these results suggest that neural processing of sentence context differs between university students with different reading histories.
Topic Area: LANGUAGE: Semantic