For decades, the common explanation for why children struggle to read has stayed remarkably consistent. Smart kids read well. Kids who don't simply aren't smart enough. And when children strain over a page, the assumption has often been that something about how they see the text is getting in the way. By this logic, reading comes down to intelligence and visual processing.

Dr. Daniel Hajovsky, associate professor in Texas A&M University's Department of Educational Psychology, has led one of the largest analyses ever conducted on the relationship between cognitive abilities and reading. Working with researchers from the University of Kansas, St. John's University, Montclair State University, and Temple University, Hajovsky sought to reveal which mental processes predict how children develop reading skills and where those connections break down.

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The skills that actually matter

The team combined 50,000 correlations across 137 cognitive and achievement test batteries into a single model. This helped them measure how much each cognitive skill actually contributes to reading while helping explain why earlier research often disagreed about what drives reading success.

The results offer a new perspective. Visual processing showed no meaningful relationship to reading ability anywhere in the analysis. General intelligence mattered, but far less than earlier research had claimed. The skills that actually predicted strong reading were ones that rarely make it into the conversation at all. The findings are published in the Journal of Intelligence.

"One notable finding was that general intelligence was less dominant than in some earlier meta-analyses," Hajovsky said. "Broad abilities such as comprehension-knowledge and auditory processing played strong, specific roles in reading beyond general intelligence, especially for decoding and comprehension."

Auditory processing is the ability to hear individual sounds inside a word and pull them apart. Comprehension-knowledge is the deep well of words, ideas, and background knowledge a child has built up from the world around them. Together, those two predicted reading abilities more reliably than anything else the study measured. Memory, mental processing speed, and reasoning all played important supporting roles.

From research to the real world

The findings give teachers a more precise way to figure out why a child is struggling. Different reading problems point to different causes and the study connects them directly.

For parents, the takeaway is that small efforts at home add up and a struggling reader is rarely a child who simply cannot do it.

"Strengthening foundational skills at home, even the ones that seem simple, can have meaningful effects on more advanced reading abilities," Hajovsky said. "Struggles in reading are not a sign of low ability but often reflect one specific skill that needs strengthening within a larger system that works together."

The best outcomes, Hajovsky said, come when schools, families, and communities support reading the same way it actually develops: as a connected chain of skills built one step at a time.