It’s possible to "forget" unwanted habits

New research shows that we can weaken and even undo practised habits by deliberately deciding to forget them.

Gesine Dreisbach and Karl-Heinz Bäuml from Regensburg University first instilled new habits in their participants by presenting them with German words and training them over many trials to make the same response to each word – a left-handed key-press for half of them, a right-hand response for the remainder.

Later, participants had to categorise the same words by gender, with key-presses again used to make the categorisations. Crucially, half the words called for the same key-presses as had been trained for those words earlier, whereas the others required a key press that was the opposite to the earlier training. Reaction time differences between matched and mismatched trials tell us how much the earlier learned habit interfered with the current task (a similar philosophy to the well-known Stroop test).

Half the participants were run normally through this process and showed interference in the gender task – making key responses that were against the grain of the earlier training slowed them down, as you'd expect. The other half of the participants, once they'd completed the initial training, were confronted with an apparent computer crash and an apologetic experimenter told them to forget all about what they'd done so far. This group weren't held back by habits on the later task: in fact, interference from the earlier training was totally eliminated.

A second experiment was similar, but this time habits were formed in a less arbitrary way. Instead of words, participants categorised numbers from one to nine as low (left key) or high (right key) in size: this left-right, low-high mapping is how we naturally consider numbers in space. In the follow-up task, which this time involved odd/even categorisation, participants in the forgetting condition did show some interference on mismatched trials, but significantly less than the other participants. Dreisbach and Bäuml suggest that habits may be harder to forget when they are formed using meaningful constructs, whereas fully arbitrary ones can be shed more easily.

This research demonstrates an intriguing proof-of-concept, suggesting that we can decide at will to forget newly-formed habits (just as we can do to some extent with episodic memories). It's possible that this could translate to more ingrained habits such as biting nails or picking your nose. After all, we know that our implicit memories are re-writable, making them open to interventions that weaken them. A big question for future research is whether directed forgetting will also be effective for habits that are pleasurable.

Further reading

Dreisbach, G., & Bauml, K. (2014). Don't Do It Again! Directed Forgetting of Habits Psychological Science, 25 (6), 1242-1248 DOI: 10.1177/0956797614526063