Schedule of Events | Symposia

The perceptual span in reading: is there a difference between dyslexic students and their peers?

Poster Session E - Monday, March 31, 2025, 2:30 – 4:30 pm EDT, Back Bay Ballroom/Republic Ballroom

Antonin Rossier-Bisaillon^1,2,3,4 (antonin.rossier-bisaillon@umontreal.ca), Julie Robidoux^1,2,3,4, Brigitte Stanké^1,2,3, Boutheina Jemel^1,2,3,4; ¹Université de Montréal, ²Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain (CRIR), ³Institut universitaire sur la réadaptation en déficience physique de Montréal (IURDPM), ⁴Centre de recherche du CIUSSS du Nord-de-l'Île-de-Montréal (CIUSSS NÎM)

Introduction: Studies of eye movements in reading show that information located outside the central fixation point – parafoveal information – facilitates preprocessing of subsequent letters and words. For instance, adult readers preview up to 15 characters to the right of the fixation point when reading. This is known as the perceptual span. However, no study has documented the perceptual span in children with a reading disorder such as dyslexia. Considering theoretical models of dyslexia, one might expect a reduction in the extent of the perceptual span for these readers. Methods: 12 dyslexic children aged 9 to 12 years old and 24 age-matched controls were recruited. Children read aloud sentences in which a precise number of characters were revealed to both sides of the fixation point, according to the gaze-contingent window paradigm used in eye-tracking (3, 5, 7, 10 characters and a baseline condition). By masking part of the letters in parafovea and measuring the effect on reading fluency, this experiment indicates the extent of the perceptual span. Results: Restrictions on parafoveal information access progressively reduce reading fluency in control participants, indicating a perceptual span of 5 to 7 characters during reading. In contrast, dyslexics are less affected by the gaze-contingent windows and present a reduced perceptual span of 3 to 5 characters. Conclusion: A better understanding of the perceptual span in dyslexia will be useful to theoretical models of the disorder, but may also inform adaptative tools for screening and addressing reading difficulties.

Topic Area: LANGUAGE: Other