How early do babies understand language? Earlier than you think

Babies may be decoding more of our language than we assume, long before they utter their first word. New research shows that infants as young as 10 months can already recognise when a verb does not match the action they are seeing, suggesting that the foundations of language comprehension are laid far earlier than previously thought.

The study, led by researchers at Cardiff University in collaboration with the University of East Anglia (UEA) and the University of Warwick, is the first to examine infants’ understanding of verbs using brain imaging technology. The findings have been published in the journal Cortex.

Using electroencephalogram (EEG) recordings, a non-invasive, baby-friendly method that measures electrical activity in the brain, the researchers tracked how infants’ brains responded to language. Ten-month-old babies sat on their parents’ laps while watching short videos of actions. Each action was paired with a spoken verb that either correctly described what was happening or deliberately mismatched it.

The babies’ brain rhythms revealed something striking: even at this early age, infants detected inconsistencies between the action and the verb used to describe it.

“Most babies begin speaking around their first birthday, and their early words are usually nouns, like ‘mama’, ‘dog’ or familiar objects from their daily lives,” said Dr Kelsey Frewin from UEA’s School of Psychology, who conducted the research at Cardiff University. “Yet caregivers use plenty of verbs when talking to infants. We wanted to understand when babies begin to make sense of these more complex word types.”

Learning verbs, she explained, is especially challenging for infants. Unlike nouns, which often refer to visible objects, verbs require babies to identify actions within continuous motion, group similar actions together, and link them to spoken words. The new findings suggest that this process may begin well before babies can speak.

The researchers caution that what they observed may represent an early sensitivity to patterns between actions and words, a developmental stepping stone rather than full-fledged verb comprehension. Still, it points to a more sophisticated level of language processing in the first year of life than earlier research had documented.

“Our findings suggest that 10-month-olds can detect action–verb mismatches,” Dr Frewin said. “Most previous research into verb learning has focused on much older children, so further studies are needed to understand exactly how these early abilities develop during infancy.”

The study adds to growing evidence that babies are active language learners from the very start, using their brains to analyse speech long before they can talk back.