Differential activation of the visual word form area during auditory phoneme perception in youth with dyslexia. Neuropsychologia 2020 Sep;146:107543
Date
07/01/2020Pubmed ID
32598966Pubmed Central ID
PMC7535924DOI
10.1016/j.neuropsychologia.2020.107543Scopus ID
2-s2.0-85087306135 (requires institutional sign-in at Scopus site) 10 CitationsAbstract
Developmental dyslexia is a learning disorder characterized by difficulties reading words accurately and/or fluently. Several behavioral studies have suggested the presence of anomalies at an early stage of phoneme processing, when the complex spectrotemporal patterns in the speech signal are analyzed and assigned to phonemic categories. In this study, fMRI was used to compare brain responses associated with categorical discrimination of speech syllables (P) and acoustically matched nonphonemic stimuli (N) in children and adolescents with dyslexia and in typically developing (TD) controls, aged 8-17 years. The TD group showed significantly greater activation during the P condition relative to N in an area of the left ventral occipitotemporal cortex that corresponds well with the region referred to as the "visual word form area" (VWFA). Regression analyses using reading performance as a continuous variable across the full group of participants yielded similar results. Overall, the findings are consistent with those of previous neuroimaging studies using print stimuli in individuals with dyslexia that found reduced activation in left occipitotemporal regions; however, the current study shows that these activation differences seen during reading are apparent during auditory phoneme discrimination in youth with dyslexia, suggesting that the primary deficit in at least a subset of children may lie early in the speech processing stream and that categorical perception may be an important target of early intervention in children at risk for dyslexia.
Author List
Conant LL, Liebenthal E, Desai A, Seidenberg MS, Binder JRAuthor
Jeffrey R. Binder MD Professor in the Neurology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdolescentChild
Dyslexia
Female
Humans
Magnetic Resonance Imaging
Male
Occipital Lobe
Phonetics
Reading
Speech Perception
Temporal Lobe