Smartphones, online learning, generative AI: The way we read has changed more in the last decade than in the previous century. So what do we actually know about what reading does for the mind? In his new book, Falk Huettig, senior investigator at the Max Planck Institute for Psycholinguistics, brings together research spanning psychology, linguistics, neuroscience and education to answer that question. The result is a systematic account of how literacy reshapes memory, attention, language processing and reasoning—and even abilities readers might not expect, like face recognition.

Cognitive enhancement is having a moment, with people turning to better sleep, exercise, nutrition, stress management and tools like caffeine or neurostimulation in search of a sharper mind. According to Huettig, one of the most powerful enhancers of all has largely flown under the radar.

"One of the most powerful cognitive enhancers, with broad and increasingly well-documented effects, is rarely emphasized in these discussions: the ability to read," he says.

An unexpected finding: Reading and face recognition
One of the more surprising threads in the book concerns face recognition. A long-standing idea in cognitive neuroscience holds that because reading is a relatively recent cultural invention, the brain has no dedicated reading network of its own, so literacy training has to borrow space from older visual systems, including the one used for recognizing faces.

"Neuroscientists have proposed that the development of reading expertise may therefore partially displace or encroach upon the face recognition network in the brain," Huettig explains. "This postulated cortical 'invasion' could result in a measurable decline in face or object recognition performance, as neural resources are reallocated to support the newly acquired reading skill."

Huettig's own research points the other way.

"Our alternative perspective challenges the idea of destructive competition by proposing that learning to read may actually enhance sensitivity to faces and other visual object categories, rather than intrusively co-opting existing face recognition territory," he says.

In studies conducted in India comparing literate and illiterate adults, his team found that "such co-opting leads to functional fine-tuning, where older networks are not diminished but rather adapted and even enhanced. We confirmed this explanation in behavioral studies: Literate people were better at face recognition than illiterate people."

A continuum, not a switch
The book argues that literacy keeps developing long after someone learns to decode text.

"Reading proficiency does not end once a reader can fluently decode a writing system," Huettig says. "Avid readers continue to automatize and refine these subprocesses and their coordination, training both lower- and—with increasing practice—higher-level cognitive functions. As a result, literate people come to 'see' the world through a fundamentally different lens than those who are illiterate or less literate."

Few people, he notes, ever reach the very top: "Only a small proportion of individuals reach the highest levels of critical reading in international assessments such as the PISA tests."

Content matters, too.

"It matters a great deal what people read," Huettig says. "Reaching these advanced levels of literacy requires regular engagement with sophisticated texts, along with the development of strong critical thinking and reasoning skills."