Do you try to keep your hands busy during stressful situations? This study suggests that there may be a good reason.
Handling stress by handling objects. I'm Bob Hirshon and this is Science Update.
In some cultures, people handle worry beads to ward off stress. A new scientific study suggests they're on to something.
It was led by Emily Holmes of the Medical Research Council in Cambridge, England. The Study volunteers watched graphic footage of car wrecks. Over the next week, images of the victims occasionally came back to haunt them.
We measured the number of flashbacks, or intrusive memories, of the film, as kept by the participants through a diary one week after seeing it.
She says people who typed a simple, reptetitive pattern on a keyboard while they watched the film suffered fewer flashbacks later on. But purely verbal distractions, like counting out loud, had no benefit.
According to theory, that's because keeping your hands and mind busy interferes with storing and encoding visual images. If the findings hold up, they could lead to new interventions for post-traumatic stress.
For example, in the emergency room, when people have come in after a trauma, and they're experiencing many flashbacks and that might be a good opprtunity to try and engage somebody in doing a job which might help improve their chance of having less flashbacks later on.
She says more research is needed to apply the findings to real-life situations. I'm Bob Hirshon for AAAS, the Science Society.
Making Sense of the Research
During the French Revolution, when the guillotine was a staple of public life, a group of women known as les tricoteuses became famous for knitting while they watched the beheadings. The image is often used to symbolize how numb the French people had become to the grisly executions. But this research suggests that the women may have been undisturbed by the guillotine because they knit, not the other way around.
The purpose of this study was to test modern theories of post-traumatic stress disorder. That's a condition in which terrifying images keep coming back to haunt you, interfering with your everyday life. (Survivors of the September 11 terrorist attacks, for example, are prime candidates for post-traumatic stress.)
Psychological theory suggests that when we're exposed to a horrifying situation, we take it in through two channels. One is the basic, primal sensory channel: the sights, sounds, sensations, and smells of the situation. The other is an intellectual channel: our brains trying to make sense of what's going on, and putting it into words and a context that we can talk about.
The experimenters wondered what would happen if you specifically blocked one of these channels while the traumatic event is going on. And they found that if you were pre-occupied with a "visual-spatial task," like typing a pattern on a computer, you didn't encode the images and sounds of the traumatic experience as strongly. As a result, subjects who kept their hands busy had fewer flashbacks.
On the other hand, people who blocked their verbal/intellectual channel while watching the traumatic film fared even worse than people who did nothing at all. They experienced more flashbacks than anyone else. Holmes explains that this may have happened because their brains were prevented from making sense of the images they saw. As a result, it was harder for their brains to stop the images from flooding back later on. The images take on the quality of a recurring nightmare that haunts you without a sensible explanation.
People across all cultures have been known to use repetitive "hands-on" tasks to ward off stress. In Greece, people handle traditional "worry beads." In some Buddhist traditions, people handle beads to help them relax during meditation. Some Roman Catholics use rosary beads in prayer, and one could argue that the beads help them feel more at peace with whatever they're praying about.
The question is, how can this knowledge be used? It's not necessarily practical to carry around worry beads or "emergency knitting" for times of stress. But Holmes thinks that giving people a repetitive manual task might help even immediately after they've been exposed to a trauma—in the waiting room of a hospital, for example. More experiments will be needed to see if the idea holds water.
Now try and answer these questions:
- According to psychological theory, what are the two main ways that the brain takes in traumatic experiences?
- Why would worry beads help reduce post-traumatic flashbacks, but counting out loud by twos make them worse?
- Are there other possible explanations for the study's results?
- How would you test the theory that repetitive hands-on tasks could help even after a trauma has occurred?
The National Center for Post-Traumatic Stress Disorders describes the features of PTSD and includes reports on national issues that can cause stress, such as the war in Iraq.
Your Brain: Emotions, by Britain's Science Museum, features a section on the brain's role in emotion.
The Emotional Brain: The Mysterious Underpinnings of Emotional Life, by Joseph Ledoux (Simon & Schuster, 1998; ISBN 0684836599) is a book about how systems in the brain work in response to emotions, especially fear.