Reading performance correlates with white-matter properties in preterm and term children

Aim: We used diffusion tensor imaging to investigate the association between white-matter integrity and reading ability in a cohort of 28 children. Nineteen preterm children (14 males, five females; mean age 11y 11mo [SD 1y 10mo], mean gestational age 30.5wks (SD 3.2), mean birthweight was 1455g [SD 625]); and nine term children (five males, four females; mean age 12y 8mo [SD 2y 5mo], mean gestational age 39.6wks (SD 1.2), and mean birthweight 3877g [SD 473]). Method: We tested whether fractional anisotropy in a left hemisphere temporoparietal region and in the corpus callosum correlates with birthweight and scores on the following three subtests of the Woodcock-Johnson III Tests of Achievement: word identification, word attack, and passage comprehension. Results: Preterm children had lower reading scores than a comparison group for all reading subtests (p<0.05). We found significant correlations between birthweight and fractional anisotropy in the whole corpus callosum (p=0.001), and between fractional anisotropy and reading skill in the genu (p=0.001) and body ( p=0.001) of the corpus callosum. The correlation between reading skill and fractional anisotropy in a left temporoparietal region previously associated with reading disability was not significant ( p=0.095). Interpretation: We conclude that perinatal white-matter injury of the central corpus callosum may have long-term developmental implications for reading performance.