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 11 y 11 mo [SD 1 y 10 mo], mean gestational age 30.5 wks (SD 3.2), mean birthweight was 1455 g [SD 625]); and nine term children (five males, four females; mean age 12 y 8 mo [SD 2 y 5 mo], mean gestational age 39.6 wks (SD 1.2), and mean birthweight 3877 g [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.