Summary: Does speaking a second language create an emotional gap between a parent and child? New research suggests that the “brain-to-brain” connection essential for bonding is remarkably resilient to language barriers. The study used light-based brain imaging to measure activity in mothers and their 3- to 4-year-old children while they played.
Researchers found that “neural synchrony”—the phenomenon where the neural networks of two people align during interaction—was just as strong when families spoke a second language as when they spoke their native tongue. This discovery provides evidence that the fundamental biological mechanism for bonding remains intact, regardless of the language context.
Key Facts
- Interbrain Synchrony: This occurs when neural activity in two brains becomes “in tune,” boosting emotional connection and communication.
- Prefrontal Alignment: Synchrony was strongest in the prefrontal cortex, a hub responsible for decision-making, planning, and emotional regulation.
- Language Resilience: Brain synchrony was equally powerful in both the mother’s native language and their acquired second language (English).
- Interactive vs. Independent: Neural alignment was significantly higher during collaborative play compared to when mothers and children played separately with a screen between them.
- No “Translation Loss”: The findings challenge the idea that using a non-native language creates an emotional distance that disrupts parent-child bonding.
Source: Frontiers
Interbrain synchrony is the simultaneous activity of neural networks across the brains of people who are socially interacting –- for example talking, learning, singing, or working together. Having brains that are thus synchronized or ‘in tune’ can help people boost their emotional connection, improve communication, and align their attention.
Neural synchrony is thought to be important for healthy bonding between parents and children. And now, a team of scientists in the UK has found that neural synchrony doesn’t appear to get ‘lost in translation’.
The results are published in Frontiers in Cognition.
“Here we show that the brains of bilingual moms and their kids stay just as ‘in sync’ through neural synchrony irrespective of whether they play in the mom’s native language or in an acquired second language,” said first author Dr Efstratia Papoutselou, a research fellow at the School of Medicine of the University of Nottingham.
“This is an important finding because it suggests that using a second language doesn’t disrupt the brain-to-brain connection that supports bonding and communication.”
Many children around the world are raised in families where more than one language is spoken. For example, in the EU the percentage of such ‘mixed households’ increased from 8% to 15.6% between 2014 and 2023. The social, cognitive, and academic benefits of growing up with more than one language are obvious.
But Papoutselou and colleagues wanted to know if multilingualism might pose a handicap when it comes to parent-child communication and bonding. The reason: even highly proficient speakers tend to speak an acquired language slower with more pauses and corrections, especially in emotionally charged or cognitively demanding contexts.
“Second-language speakers often report a sense of emotional distancing when using their non-native language, which may influence how they express affection, discipline, or empathy in parent-child interactions,” wrote the authors.
Brain power
The researchers focused on 15 families in the UK where children between three and four years old had been raised bilingually. English was not the mothers’ first language but learned at C1 or C2 level according to the Common European Framework of Reference for Languages.
Each mother-child pair visited the research clinic and sat at a table with toys. Both wore a fNIRS (functional near-infrared spectroscopy) cap to measure change in the oxygen concentration across the brain’s blood vessels – a proxy for neural activity. They were instructed to play naturalistically according to one of three scenarios in randomized order: together in the mother’s native language as at home, together exclusively in English, or silently and independently from each other with a screen in between.
The fNIRS measurements showed statistically significant neural synchrony between each mother-child pair, which was stronger during interactive than during independent play. Synchrony was especially strong in the brain’s prefrontal cortex, a hub for decision-making, planning, reasoning, and emotions. It was weaker in the temporo-parietal junction regions which regulate social cognition and attention.
Two minds moving as one
The results showed that brain synchrony was equally strong when participants played in English as when they played in the mother’s native language.
The researchers concluded that talking in an acquired language didn’t impinge on a mom’s ability to synchronize her brain activity with that of her child during interactive play. These results suggest that this key condition for effective learning and bonding can be met irrespective of language.
“Bilingualism is sometimes seen as a challenge but can give real advantages in life. Our research shows that growing up with more than one language can also support healthy communication and learning,” concluded Dr Douglas Hartley, a professor at the NIHR Nottingham Biomedical Research Centre and the study’s senior author.
Key Questions Answered:
A: While some parents report feeling “emotionally distant” when using a non-native language, this study shows that their brains don’t agree. On a biological level, the neural “handshake” between mother and child remains perfectly synchronized.
A: Neural synchrony is a key predictor of effective learning and healthy attachment. When brains align, it becomes easier to anticipate each other’s needs, share attention, and build a strong emotional foundation.
A: The research suggests that parents can feel confident using whatever language feels natural for the moment. Whether you’re disciplining, playing, or teaching in a second language, your brain is still working hard to stay connected to your child.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this language and bonding research news
Author: Mischa Dijkstra
Source: Frontiers
Contact: Mischa Dijkstra – Frontiers
Image: The image is credited to Neuroscience News
Original Research: Open access.
“The Impact of Language Context on Inter-Brain Synchrony in Bilingual Families” by Efstratia Papoutselou, Nivetha Saravanan, Guangting Mai, Samantha Harrison, Hilal Dogan Sezer, and Douglas Hartley. Frontiers in Cognition
DOI:10.3389/fcogn.2025.1695132
Abstract
The Impact of Language Context on Inter-Brain Synchrony in Bilingual Families
Background:
Bilingualism is increasingly common in families worldwide, yet bilingual individuals remain underrepresented in developmental neuroscience research. In simultaneous bilingualism, children typically acquire two languages simultaneously from birth, while their parents tend to learn the societal language later in life. These differences in language acquisition may influence how parents and children communicate, particularly when interacting in a second language.
Neural synchrony, the temporal alignment of brain activity between individuals, has emerged as a key mechanism underlying social connection, communication, and learning in early development. However, little is known about how language choice affects neural synchrony in bilingual parent–child interactions.
Methods:
This study used functional near-infrared spectroscopy (fNIRS) hyperscanning to simultaneously record brain activity from 15 bilingual mother–child dyads during naturalistic play. Each dyad completed three conditions: collaborative play in the mother’s native language, collaborative play in English (the mother’s second language), and independent play.
Neural activity was recorded from the prefrontal cortex (PFC) and temporoparietal junction (TPJ), regions associated with social cognition, joint attention, and mentalising. Families took part in a naturalistic free play paradigm, allowing them to interact in a comfortable and ecologically valid manner.
Results:
Both native- and English-language play elicited significantly greater neural synchrony across the PFC and the TPJ than independent play, validating the use of naturalistic free play paradigms. No significant overall differences emerged between native and English play, indicating that bilingual dyads maintain inter-brain coupling across languages when both partners are proficient.
Exploratory analyses suggested a trend toward higher child-directed synchrony in English play and age-related trends in mother-directed synchrony; however, these effects did not reach statistical significance.
Discussion:
Our findings show that bilingualism does not compromise mother–child neural synchrony, supporting the inclusion of linguistically diverse families in developmental neuroscience. They underscore the value of naturalistic paradigms and highlight the need for future research on language proficiency, partner familiarity, and behavioral correlates of synchrony.
This work highlights the importance of studying bilingual families in ecologically valid contexts to better understand how language use influences neural coupling in early development.
