Psychologists often do strange things in the name of research and researchers from the University of Wisconsin-Madison have been making little girls stressed to see what happens when their mothers comfort them. Nobody was hurt but 61 girls aged between 7 and 12 were asked to give a speech and solve a maths problem in front of a panel of strangers. Their heart rates and stress were monitored and these began to climb. Some of the girls were then given a hug from their mums, others were allowed to telephone them while a third group watched an 'emotionally neutral' video. Levels of the stress hormone cortisol fell and levels of the social-bonding hormone oxytocin rose by the same amount in the girls who had had a cuddle and those who had spoken on the telephone suggesting - that in this situation at least - a telephone call can be just as good as a hug.
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