By Fred McNamara, British Science Festival

In today’s social and political climate, the idea of ‘fake news’ is on everybody’s mind - the idea that the lines between truth and lies are being blurred by higher powers. However, this begs the question of how exactly we define a lie and define a truth. This was the question with which Professor Giuliana Mazzoni of the University of Hull opened her lecture You’re a Liar! When she asked the audience to define a lie, the majority were confident in their assertion that a lie is a deception, an unravelling or distortion of the truth. Her follow up question then, was to ask the audience to define the truth. They were far more subdued in their response.

Giuliana spent the next hour regaling an enraptured audience with the psychological and philosophical teachings about whether or not we lie to ourselves. The short answer? …Yes.

When we lie to ourselves however, it can be either intentional or unintentional. When recalling the past, we form the ‘truth’ through memory, and how we define memory is a complex but riveting issue.

Giuliana explained that memory is a specific perception of reality, but that reality doesn’t always conform with the objective truth. According to research from psychoanalysts and philosophers, memory can be split into several distinct categories – autobiographical memories, naive realism and memory illusions.

Autobiographical memories, as they suggest, are memories of the past. The way in which we retrieve these memories is a trickle-down system. For instance, if we’re asked to recall our work life, we first think of our work environment before going down the memory line to a specific event. This then is what we would recall of our work life, as it forms the most tangible memory.

However, to complicate things further, this type of memory isn’t just memory! When recalling the past, we cherry-pick events that feel real, events that have a tangibility to them, be that emotional or otherwise. The plausibility of the event itself can outweigh an emotional connection to that event, however. For example, do you recall falling down the stairs, and do you recall being abducted by a UFO? One is clearly more ‘real’ than the other.

Naïve realism refers to the assumed truth. We interpret the world we see and formulate what we define as a true world from that. For instance, we naturally assume the grass is green or that rocks are hard. Memory illusions can be the most deceptive. Giuliana gave a demonstration of how deceptive memory can become. She displayed a word wheel, containing nearly 20 words with similar meanings; sew, prick, stitch, etc. Afterwards, she revealed that 65% of people who look at this wheel will afterwards think the wheel included a word that wasn’t there at all, in this case, needle.

We are all capable of adding or changing details of an event based on the information we’re presented with afterwards. Another example Giuliana used was displaying a picture of two cars that had collided with each other. Using two wordings of a similar question, she asked the audience “did you see the cars touch?” and “did you see the cars crash?” The second question conjured up a more destructive image, displaying how our recollection of events can easily be altered. She explained how when we’re presented with an action, we often remember the consequence of that event which wasn’t presented to us at all. Imagination, specific details, plausibility and emotions can affect how we remember the past, whether we’re aware of it or not. As Giuliana explained: “Even when we leave memory alone, life creates false memories.” All of these types of memory then relate to a subjective truth far more than an objective truth.

Why does all of this happen? Why is it that we appear to deliberately, but not always consciously, create false memories of our past? Giuliana ended her talk by providing a disarmingly simple answer – it’s simply how our cognitive system works. A memory is a complex reconstruction of past events that uses a variety of tools that conforms to our own individual understanding of the world. These tools work towards a positive bias for ourselves. To function in this world, we’re constantly forming a positive self-image. This is where memory illusions come into play. Although these illusions are necessary for us to form an image of ourselves that can be stable and work within the world, it comes at a cost – the truth.

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