Far, Car, War, Boar: Mechanisms of Automatic Word Recognition

Poster Session D - Monday, April 15, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Niki Sinha¹ (nsinha7@uwo.ca), Marc F. Joanisse¹; ¹Western University

Word recognition is integral to fast and fluent reading. This automatic process retrieves orthographic (word form), and phonological (sound) information immediately, but is dependant on previous experience and expectations. Neuroimaging studies have shown differences in expected vs. perceived words elicit EEG responses sensitive to distinct types of word information. To assess how the brain evaluates and responds to orthographic and phonological information individually during reading, this study created sound-spelling conflict through word association. Twenty-nine English speaking adults completed a rhyming task while EEG data was recorded. Participants were instructed to judge if word-pairs rhymed or not via button press as quickly and accurately as possible. Word-pairs were visually presented in four conditions: congruent trials which shared both orthography and phonology (cool/pool) or shared neither (boat/fair), and incongruent trials with conflicting orthography and phonology (cane/rain, or most/cost). Participants had slower reaction time and lower accuracy in their judgement of incongruent trials. Comparison of congruent trials to their incongruent counterparts revealed N400 negativity occurred independently during recognition of orthographic and phonological mismatch. Additionally, a more positive P600 was found in incongruent trials than congruent, suggesting the late component was evoked by sound-spelling conflict itself. Findings indicate that both orthographic and phonological differences between word-pairs are automatically recognized at the N400 window (400-600ms), however the processing of conflict does not fully occur until the P600 interval (600-900ms). The late positivity may reflect additional error monitoring given unexpected sound-spelling mismatch, or moderation of prior expectations following conflict.

Topic Area: LANGUAGE: Other