Reading proficiency — and challenges — appear earlier than previously believed

Professionals have long understood that reading abilities begin to form before the inaugural day of kindergarten, but new investigation from the Harvard Graduate School of Education indicates they might begin as early as infancy.

The research, led by Nadine Gaab, associate professor of education, revealed that the developmental paths of children with and without reading difficulties begin to diverge around 18 months — not at age 5 or 6 as formerly believed. This revelation could carry significant policy ramifications, according to Gaab, as it stresses the imperative for early identification of struggling readers, timely intervention, and enhanced early literacy curricula in preschools.

“Our findings imply that some of these children arrive on their first day of kindergarten with their tiny backpacks and a less-than-ideal brain for acquiring reading skills, and that these variances in brain growth begin to emerge in toddlerhood,” stated Gaab. “Currently, we typically wait until second or third grade to identify struggling readers. We should locate these children and initiate intervention much earlier because we know that the younger a brain is, the more adaptable it is to language exposure.”

Gaab and her collaborators, Ted Turesky, Elizabeth Escalante, and Megan Loh, worked with a group of 130 participants, the youngest being just three months old. Eighty were derived from the Boston region, while 50 came from a sample in Canada. Over the last decade, the researchers monitored the participants’ brain development from infancy to childhood and its connection to literacy progress through MRI scans. The participant group was supplemented with scans and behavioral assessments from the Calgary Preschool MRI Dataset.

Although other studies examine brain development in children, this is the sole longitudinal study worldwide that tracks brain growth from infancy to childhood with comprehensive literacy outcome metrics, claimed Gaab and Turesky.

“While those other studies had larger sample sizes than ours, they concentrated significantly more on the typical maturation of the brain,” remarked Turesky. “We didn’t observe other studies that commenced in infancy, monitored brain maturity in the same cohort for as long as ours did, and incorporated academic outcome measures.”

The researchers further sought to expand their understanding of how brains learn in general, and how they specifically acquire reading skills. Reading is a multifaceted ability that encompasses the early maturation of brain regions and the interplay of various fundamental subskills, such as phonological processing and oral language. The brain foundations of phonological processing, previously recognized as one of the most robust behavioral indicators of decoding and word reading skills, begin to develop at birth or even prior, yet undergo further refinement between infancy and preschool, according to Gaab. The study provided additional evidence for this by demonstrating that phonological processing mediated the connection between early brain development and subsequent word reading abilities.

“Most people assume that reading begins only when formal schooling starts, or when they start reciting the ABCs,” stated Gaab. “Reading skills likely initiate their formation in utero because the fundamental milestone capability for learning to read, which encompasses oral language, entails the sound and language processing that occurs in the womb.”

“Our findings suggest that some of these kids walk into their first day of kindergarten with their little backpacks and a less-optimal brain for learning to read, and that these differences in brain development start showing up in toddlerhood.” 

Nadine Gaab

In addition to MRI scans, the study included psychometric evaluations of children, encompassing language and overall cognitive capabilities, home language, and literacy environment, to assess how these factors impact development.

“For a long while, we understood that children who struggle with reading exhibit different brain development,” explained Gaab. “What we didn’t ascertain was whether their brains adapt in response to daily challenges in school, leading to discrepancies in their brain structure. Or do children start with a less-than-ideal brain for learning to read on their first day of formal education, which likely results in reading difficulties? Our findings, alongside others in the lab, suggested that kids commence school with an inadequate brain for reading, and these brain variations manifest well before kindergarten.”

Gaab highlights her study, funded by a grant from the National Institutes of Health, as a demonstration of how fundamental research can inform both educational practices and policies. She and her team planned to continue monitoring the children involved in the study through middle and high school for an additional five years, but recent federal funding reductions have rendered that uncertain.

“The first four years of reading development is essentially oral language advancement,” she remarked. “However, the ultimate objective of reading education is to grasp what you read. Our research investigated how they acquire reading skills comprehensively. We aimed to follow them for an additional five years to assess their reading comprehension.”

Their grant proposal to sustain the monitoring of these children has received a fundable evaluation at NIH, yet due to the cessation of NIH funding to Harvard, it likely won’t be awarded, asserted Gaab.

“It’s truly unfortunate because these children will exit the study and progress to college, and they will be lost to us,” lamented Gaab. “It would yield invaluable insights to gauge their reading comprehension, even if we don’t observe their brains again, during middle school and early high school. The families of the study participants are already inquiring: ‘When will the next time we be scheduled to come in?’ We will have to inform them that this might have been the last opportunity.”