Researchers identify a key pathway linking socioeconomic status to children’s reading skills

Children from families with higher parental education tend to develop stronger reading skills — and a new study suggests this link can be largely explained by differences in oral language skills rather than structural differences in the brain. The findings, published in Developmental Cognitive Neuroscience, provide evidence that language exposure and vocabulary development may serve as the most influential bridge between socioeconomic background and reading success.

Researchers have long known that children from higher socioeconomic backgrounds often outperform their peers in reading. This trend is especially clear when socioeconomic status is measured through parental education, a common and stable indicator. While previous studies have shown that lower parental education tends to coincide with weaker reading skills and reduced brain connectivity in reading-related pathways, the mechanisms linking these factors have remained uncertain.

The current study set out to clarify these relationships by testing whether white matter integrity — a measure of brain connectivity — plays a direct or indirect role in explaining why socioeconomic status is associated with reading performance. The researchers also examined how various oral language skills might mediate this connection. Their goal was to determine whether brain structure, language ability, or both help explain how socioeconomic background influences reading outcomes.

“Reading is a pivotal skill to have in our society; it affects our educational attainment, which can influence our employment, and consequently our resources and quality of life,” said study author Martina Villa, a graduate student at the University of Connecticut. “It is important to understand how we develop reading abilities and what the ingredients are to successfully develop these skills. Previous studies have done a terrific job at identifying environmental influences and neural contributions. It is now our job to understand how these different aspects interrelate.”

The researchers used data from the Healthy Brain Network, a large-scale biobank of children and adolescents aged 6 to 15. After applying exclusion criteria, the final sample included over 3,000 participants, with more than 800 of them having complete data on brain imaging, language skills, and reading assessments.

Participants completed a series of standardized assessments designed to measure different aspects of language and reading ability. One key area was phonological awareness, which refers to a child’s ability to recognize and manipulate the sounds in spoken language. This includes skills such as blending individual sounds together to form a word or identifying what a word would sound like if one of its sounds were removed.

Vocabulary was another focus of testing. In this context, vocabulary refers to the number of words a child understands and can define. A richer vocabulary tends to support stronger reading comprehension because children who know more words can more easily make sense of what they read.

The researchers also measured reading fluency, which captures how quickly and accurately a child can read written words. This included tests that asked children to read lists of both real words and pronounceable made-up words within a limited amount of time. The ability to quickly decode unfamiliar words is often used as an indicator of reading skill, which encompasses a child’s overall capacity to recognize, decode, and make meaning from written language.

Together, phonological awareness and vocabulary were treated as components of oral language — a broader category that includes all aspects of spoken language ability, such as recognizing sounds, understanding words, and using language effectively. Oral language development typically begins well before formal reading instruction and is known to play a key role in learning to read.

To understand how these variables interacted, the researchers used structural equation modeling, a statistical method that allows for the simultaneous testing of complex relationships among multiple variables.

The researchers found that socioeconomic status predicted reading skill, but the pathway linking these two factors ran through oral language, not brain structure. Children with more highly educated parents tended to have stronger phonological awareness and larger vocabularies, and those language abilities were in turn strongly linked to better reading performance.

In contrast, white matter integrity did not appear to play a meaningful role in explaining the association between socioeconomic status and reading. While higher parental education was associated with slightly higher white matter integrity in some tracts, those differences did not predict reading ability. In other words, the structural properties of these brain pathways did not mediate the connection between socioeconomic status and reading.

The researchers were surprised by the lack of a strong relationship between white matter and reading skill. “Prior evidence for the tracts that we selected is quite robust, and I thought we would replicate those findings, even with a larger and more diverse sample,” Villa told PsyPost. “I think this goes to show how powerful sampling biases can be when we study small effects, and how careful we should be in generalizing research findings.”

The models confirmed that oral language skills acted as reliable mediators. Phonological awareness in particular showed a strong influence on reading. Vocabulary contributed as well, but to a lesser degree. These findings held across all three brain imaging models and remained stable even after adjusting for participant age and brain scan quality.

In follow-up analyses, the researchers examined whether the link between socioeconomic status and reading changed as children got older. They found no significant evidence that age altered the strength of this relationship, suggesting that the effect of parental education on reading outcomes remained relatively constant from ages 6 to 15.

Although the main pathway from socioeconomic status to reading did not appear to involve brain structure, the study did detect small but consistent associations between parental education and white matter integrity in some brain regions. These associations were especially noticeable when using more advanced imaging methods that provided detailed measures of fiber density.

In one model, higher parental education was associated with greater fiber density in all nine white matter tracts examined. However, these structural differences were not significantly related to reading performance. Only one specific tract—the left inferior longitudinal fasciculus—showed a weak link to reading ability, and even that association did not hold up across all models.

The study also found that some white matter tracts were linked to oral language skills. For example, in one model, white matter structure in the left superior longitudinal fasciculus and arcuate fasciculus predicted vocabulary scores. Another model found that the left inferior longitudinal fasciculus was associated with phonological awareness. Still, these associations were relatively modest and did not form part of a broader chain connecting socioeconomic status to reading.

Villa outlined the three main takeaways: “(1) While genetics determines a predisposition for reading proficiency, we shouldn’t neglect the effects of the environment (such as parental education, but not limited to it); (2) Oral language skills (e.g., vocabulary) play an important role in the development of reading skills; and (3) While anatomic connections between key reading areas do not mediate the effects of parental education on reading, that doesn’t imply there aren’t other ways in which they may influence the relationship — for example, these relationships may be set earlier, at a younger age than that of the participants studied here.”

While the study benefits from a large and diverse sample, it also has limitations. The data were cross-sectional, meaning all measurements were taken at one point in time. Without longitudinal data, the researchers could not determine whether changes in brain structure or language skills cause improvements in reading—or simply develop alongside them.

The study also did not explore other potential pathways from socioeconomic status to reading, such as differences in parenting style, school quality, or access to learning resources. These environmental variables might also influence reading development, either directly or indirectly, and could be considered in future research.

Although the researchers used multiple advanced imaging techniques, white matter integrity remains a complex and indirect measure of brain function. It is possible that more targeted analyses—perhaps involving functional brain activity or higher-resolution scans—could identify other neural features that help explain reading disparities across socioeconomic groups.

Another limitation relates to the sample itself. Despite being larger and more diverse than most neuroimaging studies, the sample still skewed toward families with relatively high levels of education. Future studies that include more low-income participants may offer a clearer picture of how early life experience shapes brain development and literacy.

The study, “How does SES influence the brain circuitry for literacy? Modeling the association between SES, oral language, white matter integrity, and reading,” was authored by Martina Villa, Nabin Koirala, Meaghan V. Perdue, Lee Branum-Martin, and Nicole Landi.