How baby brains 'sync up' with those of adults decoded

New York : Researchers have conducted the first ever study assessing how baby and adult brains interact during play, and found similarities in their neural activity, an advance that may lead to new understanding of development disorders like autism.

In the study, conducted by Princeton University researchers, baby and adult brain activity rose and fell together as they shared toys and eye contact.

The scientists developed a new dual-brain imaging system which uses an analysis technique called functional near-infrared spectroscopy (fNIRS) to record oxygen levels in the blood as a proxy for neural activity.

Using this setup, the researchers recorded the neural coordination between babies and an adult while they played with toys, sang songs, and read a book.

The study is based on an adult's interaction with 18 children, ranging in age from nine to 15 months.

In one part of the experiment, the adult spent five minutes interacting directly with a child -- playing with toys, singing nursery rhymes or reading 'Goodnight Moon' -- while the child sat on their parent's lap.

In the second part, the experimenter turned to the side, and told a story to another adult while the child played quietly with their parent.

The novel caps collected data from 57 channels of the brain which played roles in prediction, language processing, and understanding other people's perspectives.

The findings, published in the journal Psychological Science, revealed that during face-to-face play sessions, the babies' brains were synchronised with the adult's brain in several areas known to be involved in high-level understanding of the world.

This synchronisation may be helping the children decode the overall meaning of a story, or analyse the motives of the adult reading to them, the researchers said.

"We were also surprised to find that the infant brain was often 'leading' the adult brain by a few seconds, suggesting that babies do not just passively receive input, but may guide adults toward the next thing they're going to focus on -- which toy to pick up, which words to say," study co-author Casey Lew-Williams from Princeton University said.

According to the researchers, this two-brain approach to neuroscience may pave the way for further research analysing how coupling with caregivers breaks down in atypical development, such as in children diagnosed with autism.