Writing about a distressing or upsetting experience can help to reduce stress by changing the way the brain deals with negative emotions, new research suggests.

The act of putting feelings into words is often cathartic because it helps the brain to control regions where emotions such as fear and disgust are processed, scientists have discovered.

The findings, from a research team led by Matthew Lieberman, of the University of California, Los Angeles, suggest that one of the main motivations for writing and verbal expression, from keeping a diary to composing poetry, is the way such activity brings peace of mind and relieves stress.

“I think that the benefits of putting feelings into words is one of the indirect motivations for many of the words that get written,” Dr Lieberman told the American Association for the Advancement of Science conference in Chicago. “When people sit down to write they may not know exactly why, but there seems to be this benefit.”

The research could also be medically useful, as it suggests that writing therapy could help people suffering from psychological conditions such as social anxiety disorder, phobias or post-traumatic stress.

“We do think it has clinical implications,” Dr Lieberman said. “We’ve done some work looking at complementing an exposure therapy, for people who are high in spider fear. If you have people actually expressing their negative responses in words while they’re being exposed, you see greater attenuation over time.”

The brain’s catharsis centre is a region called the right ventrolateral prefrontal cortex, which lies next to the right temple. When this is activated, it suppresses activity in the amygdala, an almond-shaped part of the brain’s deep-lying limbic system, which processes negative emotions such as fear.

Brain scans using functional magnetic resonance imaging (fMRI) have shown that the act of writing about distressing experiences, or even thinking about expressing them in words, can activate the right ventrolateral prefrontal cortex, which then controls these negative feelings.

“The question I get interested in is why it seems to help people emotionally when they put feelings into words, whether it’s in therapy, writing a diary or journal, or poetry,” Dr Lieberman said. “Our hypothesis is this is an unintentional form of emotion regulation. The way we’ve approached this is by looking at the brain, because if you ask people they don’t think that putting feelings into words serves much of a regulatory function. But when you look at the brain it looks a whole lot like emotion regulation is going on when people put emotions into words.

“We see this pattern again and again. What it boils down to is the right ventrolateral prefrontal cortex, which seems to be involved in all different forms of self-control and self-regulation. It appears that if you get this region activated, even if you’re not trying to get it activated, it still has regulatory consequences. Putting feelings into words is one of the things that turns this region on, and therefore has regulatory benefits.

“The more that region is activated, the less activity you see in limbic regions that are involved in emotional processing, so you’ll see less activity in the amygdala than you would otherwise see to these emotional images. There seems to be a see-saw effect. The more prefrontal activation you see the less the amygdala responds.”

The researchers have yet to conduct experiments on people who keep diaries, but Dr Lieberman said that this was likely to be another way in which people activate the ventrolateral prefrontal cortex and thus control their negative thoughts.

“It’s certainly one of the inspirations,” he said. “I think that diaries probably serve as a form of daily regulation for those individuals. I would caution, though, that it probably depends on the way in which you write about these feelings. Our suspicion is that it’s probably more effective to the extent you use more abstract language, rather than truly vivid emotional language that might be reactivating the negative experience.

“We’re also working with a psychologist to look at social anxiety disorder, to see if cognitive behavioural therapy and acceptance-based therapy leads to changes in which they recruit this regulatory region when they respond to threatening situations.”

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