Poster F43, Tuesday, March 27, 8:00-10:00 am, Exhibit Hall C
The development of print sensitivity in the visual word form system in pre-readers is influenced by orthographic experience and familial risk of dyslexia
Jade Dunstan1, Xi Yu1, Jennifer Zuk1,2, Clarisa Carruthers1, Joseph Sanfilippo1, Ellen Grant1,2, Nadine Gaab1,2,3; 1Boston Children's Hospital, 2Harvard Medical School, 3Harvard Graduate School of Education
Although the visual word form system (VWFS), including the visual word form area, shows activation sensitivity to print early in development, the specialization process for print, i.e., higher activation for print compared to other categories (i.e., faces), begins only with reading instruction (Centanni et al., 2017). Moreover, individuals with developmental dyslexia (DD), a highly heritable specific learning disability, have shown impaired functional characteristics in the VWFS. It is unknown, however, whether these atypical characteristics are already present prior to reading onset and which factors affect the emergence of this deficit. To address these questions, 5-year-old pre-readers with (FHD+) or without (FHD-) a family history of dyslexia were recruited. Participants performed a visual-auditory matching task for the categories of faces, color, and print (letters and words) during fMRI. Consistent with previous findings, print-specific activation (i.e., print>face+color) was not shown in these pre-reading participants, but print-sensitive activation (i.e., print>rest) was reliably observed in bilateral occipitotemporal regions consistent with the VWFS in both FHD+ and FHD- children. Subsequent region of interest analyses conducted in the print-sensitive regions in bilateral occipitotemporal cortex further demonstrated: 1) a positive correlation between print knowledge and neural activation during the print condition across both groups; 2) FHD- children showed greater print sensitivity than FHD+ children after controlling for letter knowledge skills. Current results demonstrated that the development of print sensitivity in the VWFS is influenced by both letter knowledge and familial risk of DD, and that the occipitotemporal deficits associated with dyslexia are already present before reading onset.
Topic Area: LANGUAGE: Development & aging