When trying to avoid unwanted thoughts, people tend to reactively reject it replace it after it has occurred. Unfortunately, this approach can reenforce the unwanted thoughts. On the other hand, researchers from Hebrew University of Jerusalem found that proactively avoiding an association in the first place can be a better strategy.

For their study, they observed how 80 volunteers came up with new associations to common words. The participants viewed words on a screen and had to type an associated word. However, the group was divided in two, and one of the groups was told ahead of time that they would not receive financial incentives if they repeated associations, so they had to suppress thoughts of previous they had entered.

Using computational modeling based on reaction times and how effective participants were at generating new associations, they evaluated how people were avoiding repeated associations. The researchers found that most people were using reactive control, rejecting the unwanted associations after they have already come to mind.

In explaining their findings, the authors stated, “This type of reactive control can be particularly problematic because, as our findings suggest, thoughts are self-reinforcing: thinking a thought increases its memory strength and the probability that it will recur. In other words, every time we have to reactively reject an unwanted association, it has the potential to become even stronger. Critically, however, we also found that people can partially preempt this process if they want to ensure that this thought comes to mind as little as possible.”

Bottom line, people cannot avoid unwanted thoughts, but they attempt to decrease the chances unwanted thoughts from occurring.

I Fradkin and E Eldar. If you don’t let it in, you don’t have to get it out: Thought preemption as a method to control unwanted thoughts. PLOS Computational Biology. DOI: 10.1371/journal.pcbi.1010285