New research from Essex University has found optimum synchrony between parents and children may not be as beneficial as previously thought.

The study, the first of its kind, assessed behavioural and brain activity synchrony in 140 families, focusing on attachment.

Parents' attachment was evaluated through interviews, while children's attachment was tested by story completion tasks.

Brain activity was measured while parents and their children solved puzzles, with the results showing mothers with "insecure attachment traits" demonstrated more brain-to-brain synchrony with their children.

Dr Pascal Vrticka, from the department of psychology, said: "For secure child attachment development, sensitive and mutually attuned interactions with parents are crucial.

"If the parent, here the mother, has more insecure attachment traits it may be more difficult for the dyad to achieve optimal behavioural synchrony.

"Increased brain-to-brain synchrony may reflect a neural compensation mechanism to overcome otherwise less attuned interaction elements.

"Together with the East Suffolk and North Essex NHS Foundation Trust, we will soon start looking at synchrony within families with neurodivergent children and children with experiences of care and adoption.

"Our aim is to find behavioural and neurobiological correlates of an optimal range of synchrony to help all families with their relationships and child attachment development.

"In doing so, we must appreciate that not only low but also high synchrony can signal interaction and relationship difficulties."

The research also found the levels and nature of behavioural and brain-to-brain synchrony varied between mothers and fathers.

Fathers and their offspring displayed stronger brain-to-brain synchrony, while mothers and their children showed stronger behavioural synchrony.

The study suggests higher brain-to-brain synchrony between fathers and their children could be a neural compensation strategy to offset a relative lack of behavioural synchrony.

The study used functional near-infrared spectroscopy (fNIRS) hyper-scanning to detect this parental and child brain-to-brain synchrony, whilst parent-child interactions were video-documented and analysed for behavioural synchrony.

Dr Trinh Nguyen, formerly of Essex University and now at the Italian Institute of Technology in Rome, led the study along with Dr Melanie Kungl of the University of Erlangen-Nuremberg, Germany and colleagues from Vienna, Berlin, and Leipzig.