False memories have an upside

A false memory feels to its owner like a recollection of a real experience, but is in fact a construction of the mind. False memories are prolific because the process of memory is an inherently active, reconstructive process. Human memory then is highly fallible and prone to distortion. This sounds bad. However, in a new paper, Mark Howe and his colleagues show how our propensity for false memories can be advantageous.

Howe's team specifically tested the notion that false memories can be advantageous because they reflect the activation of concepts and ideas related to an earlier experience, which can aid future problem solving. Howe's clever experiment suggests this is particularly the case for memories that pertain to danger and survival.

Thirty adults and thirty children studied lists of ten words at a time and then attempted to recall them. Each list contained words that were all germane to the same topic. Topics were either neutral, such as "paper" or "a table", or related to a survival topic, such as "fire" or "death".

Typically when a person attempts to recall a list of words all related to the same topic they will generate one or more words that fit the theme but were in fact never seen – a kind of false memory. This possibility was important for the next stage of the experiment.

After studying and recalling four word lists, the child and adult participants completed a series of eight word puzzles known as the "remote associates test." Three words are presented and the challenge is to name a fourth word that can be meaningfully paired with all three. An example would be "rocking, wheel, high" with the solution "chair".

The clever twist was that the solution for half of the puzzles was strongly related to the theme of an earlier word list. Crucially, Howe and his colleagues found that children and adults were better at solving a word puzzle if they'd earlier had a false memory for the relevant solution. What's more, this effect was stronger for words pertaining to survival, which hints out how this could be an adaptive process with deep evolutionary roots.

Here's an example so you can see how the process worked. One of the survival word lists featured these 10 words: blaze, flame, inferno, torch, aim, smoke, dragon, log, burn, match. When some of the participants attempted to recall the list, they included the word "fire" – a false memory, since fire wasn't in the list. Later, such participants tended to perform better at the following remote associates word puzzle – cracker, fly, fighter; the answer to which is fire.

In other words, when our memories spread into related concepts, this can lead to false memories – something we usually consider a fallibility – but in fact such false memories have the potential to aid us in future problem solving on a related topic. And this seems especially to happen when the topic is survival related: participants recalled more accurate and more false memories for survival-related word lists, and they found these survival-related false memories more useful than neutral false memories for solving later related puzzles.

Here's the example Howe and his team gave for how false memories could prove useful in a real-life survival situation:

"… the person who misremembers seeing a predator while foraging for food might be more cautious upon their return to that same patch to gather more food than the person who accurately remembers that only signs (e.g., feces, scent) of the predator had been present on an earlier visit.

That false memories are an inevitable consequence of a powerful, reconstructive memory system does not make them something to be avoided. Indeed, like many things, memory illusions are neither good nor bad in and of themselves.

What determines whether they have a positive or negative consequence depends solely upon how they are later put to use."

This suggests memories for survival-related material tend to be particularly interconnected with related concepts.

Further reading

Howe ML, Garner SR, and Patel M (2013). Positive Consequences of False Memories. Behavioral sciences and the law PMID: 23843125