Stress from having to keep a secret – one’s sexual orientation, for example, or simply a forbidden word – can cause lapses in physical stamina, intellectual acuity, executive function and even email etiquette.

So says a new report, “The Cost of Keeping It Hidden: Decomposing Concealment Reveals What Makes It Depleting,” by two research psychologists, Melissa J. Ferguson at Cornell and Clayton R. Critcher at the University of California, Berkeley, published in the Journal of Experimental Psychology: General.

Email Etiquette 101

Knowing that teaching assistants controlled their grades, some experimentally stressed subjects still could not control the impulse to respond in kind to an unkind email:

“I apologize for the assignment error, but your loaded comments and critique are in no manner constructive to my academic education. P.S. Go (deleted) yourself!”

Some students tried to make excuses:

“Keep in mind I have 6 other classes on top of my investment banking internship that I have to balance.”

“These few weeks were very stressful for me, which may have affected the overall quality of my work.”

And some were conciliatory:

“I regret to hear that my assignment did not meet your expectations and will do my best to improve on future assignments.”

No grades were harmed in the course of this experiment. It was all for science.

“Before you hit the ‘send’ button and fire off that angry email, take a deep breath. Be aware that concealment may keep you from performing optimally and might impair your judgment,” says Ferguson, associate professor in Cornell’s College of Arts and Sciences. “Ask yourself: What else is going on in the back of my mind?”

Actually, that’s a trick question – typical of the experimental tasks required of research subjects (student volunteers hoping to earn extra credit in psychology courses) in the Cornell and Berkeley studies. Some research subjects were forbidden to utter certain words (like “breakfast” and “therefore”) in mock interview situations.

The constant work – monitoring their thoughts and trying not to say “therefore” or reveal sexual orientation in response to leading questions – caused what psychologists call “self-regulatory exertion and depletion.” Depleted subjects underperformed in a variety of mental and physical tests immediately after their stressful interviews.

“People have limited willpower to exert self-control. It’s the constant monitoring to make sure you don’t slip up that’s so exhausting,” Critcher told the Berkeley student newspaper, The Daily Californian. All that self-regulating can reduce productivity in the workplace, said Critcher, a professor in Berkeley’s Haas School of Business.

Cornell’s Ferguson said the research team chose sexual orientation as another kind of secret to keep because of the “social stigma” attached to that information and the fact that people often feel as though they have to conceal it: “… sexual orientation is still a sensitive part of our identities in many social and professional situations, often because there are real and harmful consequences of revealing it due to prejudice and discrimination.”

Thus, a gay man trying to conceal sexual orientation must self-monitor to avoid saying, “My boyfriend and I go there all the time!” Thinking fast, he might say, “My friend and I ...” But constant concealment and speech-suppression take a toll. Even a short span of concealment, around 10 minutes, can extract a cost. Experimental subjects who had struggled to conceal during brief, mock interviews did poorly on a variety of subsequent tests.

There were spatial intelligence tests, physical endurance tests and one with special resonance for college students: the TA’s obnoxious email test. Student-subjects received emails purportedly from TAs (teaching assistants) who controlled their grades.

“You clearly didn’t focus on the key elements of the assignment,” the email read in part. “I don’t know how anyone could have made such an obvious mistake.” Then the experimental subjects were told to respond “appropriately” to the insulting message (see sidebar). Even though an equally rude reply could hurt their grades, students suffering self-regulatory depletion (and diminished judgment) hit the “send” button without hesitation.

“Of course, no one lost points for sending rude emails. This was just a psychology experiment – with the customary safeguards of confidentiality, and a little fun thrown in,” Ferguson said. “What everyone gained was a better understanding: Concealment can be harmful. Not only does a lack of openness imperil interpersonal relationships, it can undermine people’s intellectual and physical abilities.”

The studies were supported by funds from Cornell and Berkeley.