You find yourself standing between the punch bowl and the shrimp ring making small talk with someone you don't know well, eager to duck any well-meaning requests to get together for coffee. But before you know it, you pop the question: "Wanna go for lunch?"
Research suggests that such paradoxical "rebound effects" are most likely to occur whenever our capacity for cognitive control is reduced, such as when we are stressed, distracted or overwhelmed by other tasks.
It's no wonder that our worst faux pas seem to occur after a long day of multitasking, putting up with a difficult colleague, a fussy child or bumper-to-bumper traffic. Going too long between meals can also be a problem. Glucose in the blood provides fuel that supports neural activity. If blood-sugar levels are too low, you may literally lack the energy needed to bite your tongue.
How our best attempts to avoid thinking or saying something can lead to thinking or saying that very thing has been a key research question ever since Daniel Wegner, now a professor of psychology at Harvard, and his colleagues asked participants to describe their thoughts in the now-classic "white bear" study of 1987.
Those initially asked to try not to think about a white bear initially reported fewer bear-related thoughts than those asked to think about the bear. But this was followed by a remarkable rebound effect, with far more bear-related thoughts popping into the minds of those in the "don't think" group.
The results of neuroimaging studies suggest that our attempts at controlling thoughts and feelings recruit some of the outermost areas of the prefrontal cortex. Indeed, brain scans show increased activity in such prefrontal "cognitive-control" regions when individuals are asked to suppress their responses to emotional images compared with passive viewing. But the suppression ultimately backfires, yielding greater activation of emotion-related regions, such as the amygdala and insular cortex.
Understanding the paradoxical effects of thought suppression is important in dealing with life's challenges. Well-meaning friends or relatives may suggest that you simply try not to think about troubles, when faced with a distressing situation, for example. Unfortunately, this is pretty horrible advice.
The allure of such advice is that it often seems effective … at first. Recent research has shown that smokers given such instructions - don't let yourself think about smoking - initially reached for fewer cigarettes. Unfortunately, they ended up smoking more cigarettes than those instructed to talk about their smoking-related thoughts. Similar results have been shown with individuals trying to suppress food-related thoughts.
So how can a person avoid doing the worst thing possible, if avoiding it only makes it more likely to happen?
Focus on what you want to think or do, rather than on what you trying to avoid. The brain has dedicated networks of regions that enhance neural processing of the targets of your attention, while reducing unrelated neural activity. Unwanted thoughts may best be avoided by engaging your brain in other activities.
And eating frequent small meals can stabilize blood-glucose levels. Another hors d'oeuvre could help you keep your foot out of your mouth.
Mark Fenske, co-author of The Winner's Brain: 8 Strategies Great Minds Use to Achieve Success, is an associate professor in neuroscience at the University of Guelph.