Bothered by Negative, Unwanted Thoughts? Throwing Them Away Doesn't Help

That's my interpretation of a new paper in Psychological Science (Briñol et al., 2012), which differs from the more exciting description given in a press release from APS:

Bothered by Negative, Unwanted Thoughts? Just Throw Them Away

If you want to get rid of unwanted, negative thoughts, try just ripping them up and tossing them in the trash.

In a new study, researchers found that when people wrote down their thoughts on a piece of paper and then threw the paper away, they mentally discarded the thoughts as well...
. . .
Some types of psychological therapy use variations of this concept by trying to get patients to discard their negative thoughts. But [co-author Richard] Petty said this is the first study he is aware of that has validated that approach.

So which interpretation is correct? Let's take a look, then judge for yourself.

In Experiment 1, 83 high school students participated in a course designed to prevent eating disorders. They were randomly assigned to one of four conditions in a 2 × 2 factorial design: thought direction (positive vs. negative) × treatment ('thought disposal' vs. control). The students were told they were participating in a study on body image, and asked to write down either positive or negative thoughts about their bodies for 3 min. Then the students read what they had written, followed by instructions to contemplate their thoughts and then to either throw them in the trash ('thought disposal') or check for spelling errors (control). Finally, the participants were asked to rate their attitudes toward their bodies using three different 9-point scales.¹

If throwing your negative thoughts away was beneficial, you'd predict a reduction in negative attitudes relative to the control condition (which would result in a higher score, reflecting more favorable attitudes). That is not what was observed, however. A comparison of the two white bars below reveals there was no treatment effect in the negative-thoughts condition.² In other words, body image scores did not improve in the group that discarded their lists. In contrast, there was a decline in body image for the positive-thoughts group that threw their lists away, relative to those who spell-checked.

Fig. 1 (Briñol et al., 2012). Results from Experiment 1: participants’ mean rating of their attitudes toward their own bodies as a function of the type of treatment they received and the direction of their thoughts. 

Not surprisingly, the authors had an alternate interpretation that hinged on the difference produced by thought-direction in the non-discarding control groups:

Consistent with our hypothesis that a thought-disposal treatment can influence judgments by invalidating people’s thoughts, results showed that the attitudes of participants who physically threw their thoughts away showed less impact of the thought-direction induction than did the attitudes of participants who physically retained their thoughts. ... It is important to note that because the treatment was induced after thoughts were already generated, it could not affect the valence or the number of participants’ thoughts. Rather, the treatment decreased the strength of the influence that participants’ thoughts had on their attitudes.

...and this was because of lower scores in the positive condition, rather than higher scores in the negative condition (or both effects, for that matter). So unless you want to say there were baseline differences in body attitudes between the treatment groups (which is problematic), I'm not buying it.³


Footnotes

¹ Scores were averaged across the three scales.

² However, these two conditions were not statistically compared; I'm assuming that the difference between 5.6 and 5.4 was not significant. The Thought Direction × Treatment interaction was followed up only by pairwise comparisons between Thought Direction in the different Treatment groups.

³ Psychological Science...meet me at camera 3.


Reference  

Brinol, P., Gasco, M., Petty, R., & Horcajo, J. (2012). Treating Thoughts as Material Objects Can Increase or Decrease Their Impact on Evaluation. Psychological Science DOI: 10.1177/0956797612449176