title: Too little or too much? Parafoveal preview benefits and parafoveal load costs in dyslexic adults.
abstract: Two different forms of parafoveal dysfunction have been hypothesized as core deficits of dyslexic individuals: reduced parafoveal preview benefits ("too little parafovea") and increased costs of parafoveal load ("too much parafovea"). We tested both hypotheses in a single eye-tracking experiment using a modified serial rapid automatized naming (RAN) task. Comparisons between dyslexic and non-dyslexic adults showed reduced parafoveal preview benefits in dyslexics, without increased costs of parafoveal load. Reduced parafoveal preview benefits were observed in a naming task, but not in a silent letter-finding task, indicating that the parafoveal dysfunction may be consequent to the overload with extracting phonological information from orthographic input. Our results suggest that dyslexics' parafoveal dysfunction is not based on strict visuo-attentional factors, but nevertheless they stress the importance of extra-phonological processing. Furthermore, evidence of reduced parafoveal preview benefits in dyslexia may help understand why serial RAN is an important reading predictor in adulthood.
authors.affiliation: Center for Psychology of the University of Porto (CPUP), Faculdade de Psicologia e Ciências da Educação da Universidade do Porto, Rua Alfredo Allen, 4200-135, Porto, Portugal. zanasilva@gmail.com.|Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal. zanasilva@gmail.com.
authors.forename: Susana
authors.initials: S
authors.lastname: Silva
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.
authors.forename: Luís
authors.initials: L
authors.lastname: Faísca
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.
authors.forename: Susana
authors.initials: S
authors.lastname: Araújo
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.
authors.forename: Luis
authors.initials: L
authors.lastname: Casaca
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.
authors.forename: Loide
authors.initials: L
authors.lastname: Carvalho
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.|Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.|Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors.forename: Karl Magnus
authors.initials: KM
authors.lastname: Petersson
authors.affiliation: Cognitive Neuroscience Research Group, Department of Psychology and Educational Sciences and Centre for Biomedical Research (CBMR), University of Algarve, 8005-139, Faro, Portugal.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Reis
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D016022:Case-Control Studies; D004410:Dyslexia / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D011932:Reading; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Dyslexia; Eye-tracking; Parafovea; Reading predictors; Serial RAN