Date Published: May 2, 2019
Publisher: Public Library of Science
Author(s): Jolijn Vanderauwera, Ellie R. H. van Setten, Natasha M. Maurits, Ben A. M. Maassen, Rex Eugene Jung.
A child’s school achievement is influenced by environmental factors. The environmental factors, when represented by socio-economic status (SES) of the family, have been demonstrated to be related to the reading skills of a child. The neural correlates of the relation between SES and reading have been less thoroughly investigated. The present study expands current research by exploring the relation between SES, quantified by paternal educational level, reading of the offspring and the structure of white matter pathways in the left hemisphere as derived from DTI-based tractography analyses. Therefore, three dorsal white matter pathways, i.e. the long, anterior and posterior segments of the arcuate fasciculus (AF), and three ventral white matter pathways, i.e. the inferior fronto-occipital fasciculus (IFOF), the inferior longitudinal fasciculus (ILF) and the uncinate fasciculus (UF), were manually dissected in the left hemisphere of 34 adolescents with a wide range of reading skills. The results demonstrated a relation between word reading, SES quantified by paternal educational level, and fractional anisotropy (FA) within the left dorsal AF segment and the left ventral UF. Thus, the present study proposes a relationship between paternal educational level and a specific white matter pathway that is important for reading, aiming to guide future research that can determine processes underlying this relationship.
The environment in which a child grows up is known to substantially influence a child’s school achievement . Parental characteristics are among the important factors influencing a child’s environment [2,3]. These parental-driven environmental characteristics can be represented by parental socio-economic status (SES). Quantification of SES is most commonly based on parental educational level, family income and parental occupation [4,5]. Lower socio-economic status has been related to poorer cognitive skills in children [6–8] as well as in adults [9,10], especially in the domains of executive functioning, language and memory [1,6,11–15]. Notably, a gap in reading achievement has been demonstrated in children with poorer SES [6,16–22], suggesting a link between reading and SES of the family in which the child grows up.
Characteristics of the participants and their parents are presented in Table 1. As indicated in the methods section, statistical analyses were restricted to paternal educational level, given that more data were missing for the mothers (fathers: 0 missing, mothers: 4 missing) because more fathers were diagnosed with dyslexia compared to the mothers, and the educational level of the mothers was not equally distributed.
The present study investigated the relation between socio-economic status (SES), reading and structural organization of dorsal and ventral white matter pathways of the left hemispherical reading network. The results revealed a relation between SES, defined by paternal educational level, word reading and white matter structure, as quantified by FA, for the dorsal long arcuate fasciculus (AF) segment and the ventral uncinate fasciculus (UF) segment. The associations with paternal educational level were most robustly found in the ventral UF. The present study thereby confirms the relation between SES of the family and reading of the offspring, and expands the previously reported relation between SES, reading and white matter structure  by allocating the relation to specific dorsal and ventral white matter pathways, i.e. the left long AF and the UF, respectively.