Just watching another person shiver can cause our own temperature to drop, scientists have found.
Volunteers who viewed videos of actors plunging their hands into ice-cold water, experienced a simultaneous drop in the temperature of their own hands.
Neuroscientist Neil Harrison, from the University of Sussex said: ‘We believe that this mimicry of people’s bodily response helps us understand how they are feeling.
苏塞克斯大学（The University of Sussex）的神经系统科学家尼尔·哈里森（Neil Harrison）说，“我们认为这种人体反应的模拟行为可以帮助我们理解他人的感受。
‘Humans are profoundly social creatures and much of humans’ success results from our ability to work together in complex communities – this would be hard to do if we were not able to rapidly empathise with each other and predict one another’s thoughts, feelings and motivations.’
It’s believed that ‘mirror neurons’ in the brain are behind the phenomenon.
Dr Harrison explained: ‘Mirror neurons found in very specific parts of the brain are known to fire when we perform an action or observe a similar action in others – it has been proposed that more general mirror properties may also exist across many other brain areas.'
And the more naturally empathetic the person, the more likely they are to mimic another person’s responses, he added.
For the study, which was published in the Plos One journal, researchers asked 36 participants to watch eight videos that showed actors with one of their hands in visibly warm or cold water.
这一研究刊登于公共科学图书馆期刊（The Plos One journal），研究者让36名参加者观看八段视频，视频中演员将一只手放入明显温暖或是冰冷的水中。
In the four 'warm' videos, the first 40 seconds showed the actor gradually adding hot water from a steaming kettle into the container, checking the temperature of the water every few seconds.
The actor was then shown with their hand immersed in the water for a further two minutes and 20 seconds.
The actor did the same in the 'cold' videos, but instead, filled the container with a bag of ice.
Four control videos with the actors’ hand in front of a tank of room temperature water were also shown.
None of the actors’ faces could be seen and the temperature of the room was kept at a constant 21°C (70°F).
The researchers monitored the participants’ hand temperature while the watched the videos.
They found that when they viewed the actors putting their hands in the iced water, their temperatures dropped by a small, but statistically significant, amount: 0.2°in their left hands, and 0.05°in their right.
There was no significant change in their hand temperature when they watched the control videos and the warm water videos.
Dr Harrison said: ‘Though we didn’t see a significant change in participants’ own hand temperature when they viewed the warm videos, we think that this is probably because the warm videos were less potent.
'The only cues that the water was warm was steam at the beginning of the videos and the pink colour of the actor’s hand, whereas blocks of ice were clearly visible throughout the duration of the cold video.
‘There is also some evidence to suggest that people may be more sensitive to others appearing cold than hot. Why this may be the case is currently unclear.’