The more we know about a subject, the easier we are to deceive

Knowing a lot about a subject means that you are more likely to have false memories about it.

This is the paradoxical conclusion of research being presented today, Thursday 1 September 2016, by Dr Ciara Greene from University College Dublin to the annual conference of the British Psychological Society's Cognitive Psychology Section in Barcelona.

Dr Greene and Anthony O'Connell, then a Masters student at University College Cork, asked 489 participants to rank seven topics (football, politics, business, technology, film, science and pop music) from most to least interesting.

They were then asked if they remembered the events described in four news items about the topic they selected as the most interesting and four items about the topic selected as least interesting. In each case, three of the events depicted had really happened and one was fictional.

The results showed that if someone was interested in a topic, this increased the frequency of accurate memories relating to that topic. But it increased the number of false memories too  as 25 per cent of people experienced a false memory in relation to an interesting topic, compared with 10 per cent in relation to a less interesting topic.

Having a high level of knowledge about a topic as measured by the number of true memories recorded, rather than just an interest, increased the frequency of false memories too. People who were more knowledgeable about a subject were nearly twice as likely to remember incidents relating to that topic that never happened.

Dr Greene said: "Increasing scientific and public understanding of the causes of false memory is an important goal, particularly in light of some of the more negative consequences associated with the phenomenon, including faulty eyewitness accounts and the controversies surrounding false memories of traumatic childhood events. I hope that promotion of knowledge about false memories may provide some inoculation against their harmful effects."

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