People can tolerate more pain if their romantic partner is next to them, scientists have discovered.
In a series of experiments, researchers gradually applied more pressure onto the fingernails of participants.
They found volunteers were able to tolerate pain more when their loved one was with them in the room than when they were alone.
But their romantic partners weren't allowed to hold their hands or speak to them, and were only told to make eye contact.
And the scientists in Austria even found the painkilling effect was greater if their partner was considered to be empathetic.
Scientists find people can tolerate more pain of gradual weight on their fingernail if their romantic partner is next to them without even holding hands or speaking
Participants also rated how painful the pressure was on a scale of one to ten while their finger was trapped under 3kg of weight. When their partner was there, they rated their pain as lower
Professor Stefan Duschek, lead researcher, said: 'Repeatedly, talking and touching have been shown to reduce pain.
'But our research shows even the passive presence of a romantic partner can reduce it and that partner empathy may buffer effective distress during pain exposure.
'The results confirm the analgesic effects of social support, which may even occur without verbal or physical contact. '
Forty-eight straight couples were recruited by the researchers at The University of Health Sciences, Medical Informatics and Technology.
THOSE IN A HAPPY MARRIAGE LIVE LONGER
A study found participants who were happy in their marriage were less likely to die within an eight-year period.
Researchers believe those who are content with their other half are more motivated to lead an active lifestyle.
But living with someone who is 'depressed and wants to spend the evening eating chips in front of the TV' encourages unhealthy habits, they add.
The research was carried out by Tilburg University in the Netherlands and led by Dr Olga Stavrova, from its department of social psychology.
After eight years, around 16 per cent of the participants had died.
Results - published in the journal Psychological Science - revealed these fatalities tended to affect those who reported poor relationship and life satisfaction.
This remained true even after adjusting for the participants' health and 'sociodemographic variables', such as level of education and income.
In 2010, the World Health Organisation found marriage can reduce the risk of depression and anxiety and singles are more likely to suffer the blues than those who are married.
One person from each couple went through experiments, in which their index finger was put into a machine.
The machine slowly added weight onto the fingernail until participants gave a stop signal when the pain was too much.
This was repeated three times, both alone with a study conductor, and when their partner was sitting one metre away from them.
The couple were able to make eye contact but not speak to each other.
Participants also rated how painful the pressure was on a scale of one to ten while their finger was trapped under 6.6lbs (3kg) of weight.
Participants had a higher pain tolerance when their partner was there, and rated their pain as lower.
The team also wanted to see how much pain was reduced by dispositional empathy – which is when a person is good at imagining the feelings and experiences of someone else.
After the study, the couples did a 16-part questionnaire that assessed how empathetic each individual was.
Participants who had empathetic partners appeared to have a greater increase in their pain tolerance than those who did not.
Previous studies have also found vocal empathetic soothing from a partner promotes intimacy, therefore reducing a perceived threat.
The authors of the study wrote: 'It may be argued that day-to-day experience with a highly empathetic partner leads to a general expectation of his or her compassion and emotional support in threatening situations; as such, the sole presence of the partner may reduce distress and pain sensitivity.'
They add that the theory pain was reduced by having a distraction in the room cannot be ruled out.