Q: Regarding your column on people spreading secondhand stress at the office, how is stress actually conveyed from one person to another?

—E.K.

A: Working with people who are stressed has both physiological and emotional effects. Perspiration produced under emotional strain releases alarm pheromones, or airborne chemical signals. When inhaled by others, these substances activate the amygdala, the region of the brain linked to emotional arousal, according to a 2009 study in PLOS One.

Researchers in the study compared 32 subjects’ reactions to sweat collected from people doing their first sky-dive, including a one-minute free fall, with the response to sweat from people running on a treadmill without any emotional strain. Both types of sweat were kept free of bacteria that cause a bad odor, and both smelled the same, but the exercise sweat didn’t cause the same response, the study showed. Another study, published in 2011 by researchers at the State University of New York at Stony Brook, found that inhaling substances from sweat produced under stress causes people to focus more closely on details in others’ facial expressions that might signal a threat.

People who act stressed create social pressure, too. A boss who rushes constantly sparks anxiety among others who assume they should be racing around, too. Also, it is stressful to try to communicate with a co-worker who seems chronically overburdened, making co-workers reluctant to ask for help or even a moment to talk.

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