Dr Vicky Leong from the University of Cambridge's Department of Psychology, who led the study said, "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."
She added, "Depression can have a powerfully negative effect on the 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 needed to thrive."
Dr Wass, a senior lecturer in the School of Psychology, recently secured a prestigious 1.5 million Euro five-year grant from the European Research Council to find out more about how patterns of brain activity are 'shared' between infants and adults, using techniques similar to those in the current study.
Dr Wass and his collaborators are also looking at how the babies of depressed mothers may show less evidence of learning because of a weakened neural connection between mother and infant. Mothers who experience a persistently low or negative mental state due to clinical depression tend to have less interaction with their baby. Their speech is often flatter in tone, they make much less eye contact, and they are less likely to respond when their baby tries to get their attention.