My mother used to say to me, "Take off that sweater! You're making me hot just looking at you." Who knew she wasn't just being a mom. Seeing someone who is hot or cold can cause a psychosomatic response, according to a new study published in PLOS ONE.

"During social interactions, our own physiological responses influence those of others," researchers wrote. "Synchronization of physiological (and behavioural) responses can facilitate emotional understanding and group coherence through inter-subjectivity."

Basically, our empathetic nature can cause us to feel a temperature change if we observe someone else experiencing that temperature change.

The study showed thirty-six healthy participants' videos of people with their hands submerged in either hot or cold water. The participants rated the hands in the video as being either warm or cold, and researchers found that the participants' hands reflected what was being shown in the video.

"Participants' own hands also showed a significant temperature-dependent effect: hands were significantly colder when observing cold versus warm videos," researchers wrote.

"To conclude, here we show that healthy individuals are sensitive to observable signals of another's peripheral body temperature and further show contagion of their temperature, particularly in the context of cold. Inter-individual differences in temperature contagion are marked and show a complex relationship to inter-individual difference in empathy. Interestingly, abnormal temperature regulation is also observed in disorders of social cognition such as autism and Schizophrenia suggesting interest in measuring temperature contagion in these populations," researchers concluded.

When you're walking to work in the blistering winter air, think warm thoughts. Shivering could make you (and your fellow commuters) a few degrees colder.