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Do you remember the time President Obama shook hands with Iranian president Ahmadinejad? If you took part in a recent psychological study, it’s possible that you will. More than 5,000 participants were presented with doctored photographs representing fabricated political events, with around half claiming to have memories for the false scenarios (Obama has, of course, never shaken hands with the Iranian president). Part of a decades-long program of research by psychologist Elizabeth Loftus, the latest study provides a neat demonstration of how our memories are created in the present rather than being faithful records of the past.

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The popular perception of memory shows a considerable lag with the new scientific consensus. The psychologists Daniel J. Simons and Christopher Chabris have conducted two large-scale surveys showing that roughly half of respondents thought that memory works like a video recorder. And although many people do recognize that their memories are fallible, there is much less understanding of precisely how and why they fail us.

Memory is a system with many moving parts, and thus many processes that can go wrong. The various ‘sins of memory’ (in Daniel L. Schacter’s phrase) give us the best clues about how this complex mental function works. Psychologist and neuroscientists have taken advantage of these clues to explore the strong links between imagination and memory, to demonstrate how social factors influence our recollections, and to show how memory may actually have evolved to predict the future rather than keep track of the past. There is arguably little evolutionary advantage to being able to recall the past in vivid detail; it is much more useful to be able to use past experience to predict what comes next.

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So why are we so attached to our idea of memories as fixed, unchanging possession? There are many reasons, but one is that memories are foundational for our sense of self. This is particularly true for early childhood memories (which the scientists tell us are the most unreliable of all). In her striking description of lying as a small child in her cot at St. Ives, Virginia Woolf noted that this wasn’t just her earliest memory; it was the moment she became the person (and the writer) she was. It is no wonder that we resist the idea that our memories are collages of disparate sources of information, assembled and reassembled long after the event.

Bracing as it might be, this new way of thinking about memory does not have to lead to self-doubt. It simply requires that we take our memories with a pinch of salt, and forge new relationships with them. They may be a kind of fiction, but the manner of their making speaks volumes about those who create them. In the Obama-Ahmadinejad study, the researchers found that events were more likely to be falsely recalled if they fit the individual’s political affiliations (conservatives were more likely than liberals to ‘remember’ the Ahmadinejad handshake, for example). Whether the events happened or not, your biases and beliefs shape the kind of memories you form, and thus reveal the kind of person you are.

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