A phone call from mother to daughter is just as comforting as a hug, scientists find

As the slogan goes, it's good to talk. Scientists have discovered that a conversation on the phone can be as good as a hug in terms of boosting the "love hormone" oxytocin – at least when it comes to mothers and daughters.

Oxytocin is often called the love hormone because it appears to promote social bonding and is released into the bloodstream when babies suckle at the breast or when lovers embrace. But now researchers have found that a telephone conversation can also do the trick. The scientists investigated oxytocin levels in girls aged between seven and 12 after they had gone through the stressful experience of reading aloud to strangers. After the event, a comforting hug by their mothers saw oxytocin levels rise in the girls' bloodstreams – but so did a simple phone call from their mums.

It is the first time scientists have shown that talking alone can raise levels of the hormone, which is known to be crucial for the formation and retention of social bonds. They suggest the findings could be important in understanding what can go wrong with children who become institutionalised from an early age and find it difficult to form social relationships in later life.

Some of the girls in the study were not allowed to interact in any way with their mothers immediately after their ordeal and their oxytocin levels continued to remain low, while levels of the stress hormone cortisol remained high. This showed how important a mother's attention is to a child's oxytocin levels, even if the contact is in the form of a phone call, the scientists said.

"The children who got to interact with their mothers had virtually the same hormonal response, whether they interacted in person or over the phone," said Professor Seth Pollack of the University of Wisconsin-Madison, who led the study published in the Proceedings of the National Academy of Sciences.

"It was understood that oxytocin released in the context of social bonding usually required physical contact. But it's clear from these results that a mother's voice can have the same effect as a hug," Professor Pollack said.

"It stays well beyond that stressful task. By the time the children go home, they're still enjoying the benefits of this relief and their cortisol levels are still low. It's hard to get cortisol up. It's hard to get oxytocin up. That a simple telephone call could have this physiological effect on oxytocin is really exciting," he added.

Dr Leslie Seltzer, who carried out the study, suggested that children who lack close parental contact in early life may suffer in later years with personal relationships partly because of an inability to produce oxytocin in response to the normal stimuli.