The brains of mothers and their babies sync up more easily when the mother is happy, a new study from Cambridge University has shown.

Researchers discovered that mothers’ and babies’ brains act together in a ‘mega-network’ where brainwaves fall in line, allowing for a greater connection and empathy.

But that level of connectivity varies according to the mother’s emotional state.

When mothers express more positive emotions their brain becomes much more strongly connected with their baby’s brain.

Scientists think that a greater connection may help the baby to learn more quickly and its brain to develop more fully. So if mothers are happy it is likely to improve child development.

“Our emotions literally change the way that our brains share information with others - positive emotions help us to communicate in a much more efficient way,” said Dr Vicky Leong, of University of Cambridge’s Department of Psychology.

“Depression can have a powerfully negative effect on a parent’s ability to establish connections with their baby.

“All the social cues that normally foster connection are less readily available to the child, so the child doesn’t receive the optimal emotional input it needs to thrive.”

The research, published in the journal NeuroImage, used a method called dual electroencephalograhy (EEG) to look at brain signals of seven pairs of mothers and babies while they were interacting with each other.