A recent study published in Developmental Science reveals that preschoolers' brains respond differently when stories are read to them from a book compared to when they are presented on a screen. Using a neuroimaging technique called functional near-infrared spectroscopy (fNIRS), researchers found that live book reading triggered stronger activation in the right hemisphere of the brain, especially in areas linked to social understanding, whereas screen-based storytelling led to more balanced activation across both hemispheres.
Reading books to young children plays a crucial role in their language development and brain growth. It exposes them to rich vocabulary, narrative structure, and interactive social experiences with caregivers. In contrast, concerns have grown around excessive screen time, as studies have linked it to language delays and weaker connectivity in brain areas critical for literacy.
While previous research has broadly compared the effects of books and screens on children's development, this study took a closer look at how these activities affect brain function in real-time. The goal was to directly measure brain activity during both live reading and screen-based storytelling.
The study involved 28 typically developing children between the ages of 3 and 6, most from English-speaking homes, with some multilingual participants. Each child experienced two storytelling sessions: one featuring a live adult reading a printed book, and another in which the same story was presented as an audio recording paired with images on a computer screen. The stories were matched for length, vocabulary, and content.
Throughout both sessions, researchers recorded the children's brain activity using fNIRS, a method that tracks changes in blood oxygenation linked to neural activity. They focused on brain regions involved in language, story comprehension, and social cognition—specifically the inferior and middle frontal gyri, the superior and middle temporal gyri, and the temporoparietal junction.
Results showed that live book reading led to greater activation in the right temporoparietal junction—an area tied to social processes like joint attention and understanding others' perspectives. This activation was significantly stronger during book reading than screen time. More broadly, the right hemisphere was more active during live reading, while screen time activated both hemispheres more evenly, without a clear lateralization pattern.
These findings suggest that live book reading may engage children's brains in more socially-oriented cognitive processing compared to passive screen viewing. Book reading likely encourages attention to the reader's emotions, tone, and shared focus on the story—factors that involve right-hemisphere brain networks. In contrast, screen-based stories may prompt more isolated language processing with less social engagement.
While the findings align with past studies showing the benefits of book reading for language and social development, they also highlight important nuances. The right-hemisphere activation during live reading seems to reflect children's sensitivity to human interaction, even in the relatively scripted setting of this experiment.
The study has some limitations. The sample size was small, and missing data from some brain channels reduced the strength of the conclusions. Additionally, the participants were mostly from high-income, highly educated families, limiting how widely the findings can be generalized.
Researchers also noted that the structured format of the book reading sessions, designed for consistency, may not reflect the natural, conversational style of everyday parent-child reading. Future studies could explore brain responses during more typical, interactive reading experiences.
Importantly, while this study revealed differences in brain activation, it did not directly assess children's language learning or academic outcomes. These questions and many others will undoubtedly be investigated in future studies.
Despite its limitations, the study adds valuable insight into how early experiences shape brain development. It underscores the importance of live, interactive activities like book reading, which appear to activate brain networks crucial for social understanding and communication.
The results also raise questions about the effects of screen media, particularly when children engage with it passively. While some digital media can be educational and interactive, this research suggests that live social interaction remains vital for the cognitive development of young children.
Sources:
https://onlinelibrary.wiley.com/doi/epdf/10.1111/desc.13615
https://psychcentral.com/lib/what-is-functional-optical-brain-imaging
https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2015.00719/full
