Thought you had the facts about last nights argument?  Just listening to another person’s version of the same argument can overwrite your own memory.  It’s a little discombobulating to find that memory is not a static thing.  Memory is subject to influence every time it is reactivated.

False Memories Are Contagious- Similar to Contagious Yawning

Your past is not your own. Through simple nudges, your friends, colleagues and strangers can change your recollections in ways you will never realise.


Starting in the early 2000s, Michelle Meade at Montana State University has shown that false memories are contagious and can easily spread from one person to another. She would ask pairs of participants to view a household scene; they were then allowed to discuss what they had seen before they took a test. If one of the pair happened to drop in a few false details, they would stick in the other’s mind, so that they would swear they had seen it themselves.


Even explicit warnings – explaining the flaws in their partners’ recall – failed to reduce the errors entirely. “The flipside to that is that sometimes the explicit warnings also reduce correct recall – they think that person is unreliable I should cut off everything they say,” explains Meade.


Besides seeding a false memory that we believe to be true, our acquaintances can also sow a grain of doubt about the memories we thought we could trust. Robert Nash, a psychologist at Aston University in the UK, knows this only too well. Looking back at his sister’s graduation, he could clearly recall that the British newsreader Trevor McDonald had attended the event. “I was absolutely convinced,” he says. But when, before his own graduation, he mentioned the event to his parents, he found them laughing in disbelief. A bit of research online only left him with more doubts. “And the more I thought about it, the more I knew that it wasn’t plausible.”


Despite his suspicions, the memory hasn’t disintegrated under the scrutiny, though. “I can still picture it.” This is an example of a “non-believed memory” and it shows the fourth way our social interactions influence our recollections – by questioning them and forcing us to confront our own failings.


Nash and his colleagues recently explored surveys from hundreds of participants, finding three distinct flavours of non-believed memories. The “classic non-believed memories” might be similar to the kind Nash described: you have a vivid recollection, but you now strongly suspect that it is false; with others, there’s a grain of doubt – you have the sense it’s not true but you might still defend it. The third kind are weak non-believed memories. They are vaguer; you might feel confident that you remember something but you aren’t clear about the details, and you now doubt its very occurrence.


Nash has also investigated the ways we test the truth of our memories. Previous research had shown that our feelings of authenticity may depend on the assumption that our memories are accurate – so you might expect that people would put in a lot of effort to verify the facts. So along with his collaborators, he asked participants to imagine that someone had challenged a cherished memory, and asked them to describe how they would test whether it was true or not. They also had to rate how much effort it would take. In almost every situation – whether the memories were important or trivial, from the distant past or more recent – he found that participants would opt to use quicker but less reliable options. These might include asking a friend or family member who may be unreliable themselves instead of more difficult, but more accurate, attempts to get to the truth, such as checking the hard evidence of medical records or looking through old diaries.


This ‘principle of least effort’ was true even if they asked the participants to imagine that they would need to verify the memory for the police – a situation with serious consequences. “They still chose the ‘cheap’ strategy over the reliable strategy,” he says. We may think we value the truth, but “people don’t question their memories enough to think it’s worth putting in the effort”. (Truman Capote was strongly in this camp; when writing his non-fiction novel In Cold Blood, he claimed never to have used a tape recorder for his interviews, instead relying purely on his own recall.) read more at

So, it seems, memories are not to be trusted.  This is definitely something to think about!