Researchers at Karoli Gaspar University in Hungary found that stroking a partner's forearm boosts mood and happiness by up to 50 per cent. The technique works even for people in a bad mood or experiencing relationship troubles.
The study involved 110 men and women who were quizzed about their relationship satisfaction. Researchers drew a 10cm (4in) line along each participant's inner right forearm, starting at the wrist and extending towards the elbow, and placed electrodes on their chests to monitor heart rhythm.
To test the effect, researchers first showed participants images designed to trigger a negative mood. One group then had the line stroked by a romantic partner using a watercolour brush at five centimetres per second for three minutes, which matches the speed of falling cherry blossoms in spring.
Testing the arm stroking technique
A second group was stroked at the same speed by a researcher, while a third group simply looked at their arm without any stroking. Men and women stroked by their romantic partner saw mood scores improve by 40 to 50 per cent, even if they were not completely satisfied in their relationship.
The mood improvements for those stroked by a partner were 20 percentage points higher than for those stroked by a researcher. Researchers suggested the technique was successful enough to potentially be used in couples therapy.
Biological reason behind the results
One theory explaining the results involves nerves called C-tactile fibres located in hairy skin. These nerve fibres respond to slow skin-to-skin contact, which triggers social bonding and reduces stress.
Writing in the International Journal of Psychophysiology, the research team wrote: "For those who respond well to stroking it might be usable even under difficult emotional circumstances, such as in couples therapy."
