Whether you're a person biting her nails during a phone interview or a polar bear pacing its cage, anxious animals often do the same thing over and over. Extreme cases of repetitive behavior show up in people with obsessive-compulsive disorder or autism. Now researchers have shown that even a simple, anxiety-inducing experiment can make an average person act in a repetitive and ritualized way. "A lot of social theorists have talked about the link between anxiety and ritualization," says Martin Lang, a graduate student at the University of Connecticut. However, "There were, to our knowledge, no experimental studies with humans that clearly demonstrated this link." So Lang and his coauthors turned to psychology's most popular subjects: university students. And to inspire dread in those students, the researchers used a popular fear: public speaking. The subjects were 62 students from Masaryk University in the Czech Republic, male and female, with an average age of just under 24. When they arrived for the study, they were fitted with a heart-rate monitor and an accelerometer on each wrist. Then they sat at a table that held a decorative metal object. Half of the subjects were told they'd have to give a five-minute speech about this object to an art expert. There was a list of seven questions they'd need to answer in their talks, such as "How old do you think the object is?" and "What art genre does this object belong to?" And, oh yeah, they had three minutes to prepare. The other half of the subjects were asked to look at the same object and think about the same list of questions. But there was no threat of public speaking. At the end of the task, researchers asked everyone to pick up the object and polish it with a wet cloth until they thought it was clean. Then the public-speaking subjects learned that they wouldn't have to present after all (the "art expert" was temporarily unavailable, i.e. imaginary), and everyone filled out a questionnaire. People who'd been preparing for a presentation said they felt more anxious, and the heart-rate monitors showed that their pulses had quickened. Thanks to the accelerometers subjects wore on their wrists, researchers could also measure the movements they'd made while cleaning the metal object. And they saw differences between the anxious subjects and the others. Because of the object's size and shape, Lang says, there were various ways you might clean it. You could cover the whole thing, or you could go back and forth over a small spot. Subjects who weren't anxious varied their movements. They might alternate between short and long swipes, for example. But anxious subjects were more repetitive and predictable in their motions. "On the whole," Lang says, anxious people "focused on smaller areas of the object and cleaned them more meticulously." Not that these subjects realized what they were doing. Some didn't even acknowledge feeling anxious. To Lang's surprise, he says, the threat of public speaking triggered these repetitive behaviors "even when participants did not consciously perceive the situation as stressful." This might suggest that acting repetitively when we're stressed is a "deeply ingrained" pattern, Lang says. "If ritualization is a natural response to anxiety, then we might be able to develop effective techniques to help people deal with chronic and acute stress." Learning more about this link might also help researchers understand why people with OCD and autism spectrum disorders have compulsive, ritualized behaviors, and how to treat them. And if none of that pans out, at least someone's metal circle decoration is really, really clean now.
Images: top by bark (via Flickr); bottom, Lang et al.
Lang M, Krátký J, Shaver JH, Jerotijević D, & Xygalatas D (2015). Effects of Anxiety on Spontaneous Ritualized Behavior. Current biology : CB, 25 (14), 1892-7 PMID: 26096971