Just looking at someone else shiver from the cold can cause certain parts of our body to drop in temperature, a new study suggests.
Researchers led by Ella Cooper from the University of Sussex and John Garlick from University College London (UCL), made 36 participants sit in a temperature-controlled room and watch videos of actors placing one of their hands in either visibly steaming water, ice water, or neutral still water.
Each subject watched ten total videos, four each featuring warm and cold water with different actors who used either their left or right hand, as well as two control videos. All of the videos lasted two minutes.
The researchers closely monitored subjects' heart rates and hand temperatures throughout the process, 'Real Clear Science' reported.
While watching the warm and neutral videos did not produce any changes in subjects' hand temperature, watching the cold videos caused a small, but unmistakable drop.
The temperature of subjects' right hands fell by an average of 0.1 degrees Fahrenheit, and the temperature of their left hands fell 0.4 degrees. There was no change in heart rate.
Researchers suggest that the warmth of the water, as indicated by the steam, may not have been as visible. On the other hand, the ice water was clearly frigid.
They also note a prior review which showed that it is easier to elicit a decrease in skin temperature than an increase.
The research provides further support to emotional contagion, the tendency for two individuals to mimic each other's expressions and emotional states.
