The science behind why we take selfies

The selfie has arguably become the greatest photographic trend of our time. Why are we so interested in taking and sharing selfies and how does observing an image of yourself differ from observing a picture of someone else, asks University College London neuroscientist James Kilner.

In everyday social situations we spend a lot of our time looking at and interpreting other people's faces and facial expressions. Indeed, reading and responding correctly to other people's facial expressions is essential for successful social interactions.

Through our lifetimes we become experts at recognising and interpreting other people's faces and facial expressions. In contrast, we have very little experience of looking at our own faces.

Our perception of our own facial expression comes from our sense of feeling our faces move. This lack of visual knowledge about our own faces means we have a very inaccurate representation of what our own faces look like at any given time. For example, it has been demonstrated that when people are shown an image of themselves and asked to match it they are unable to accurately produce the same facial expression without being able to see themselves.

This lack of knowledge about what we look like has a profound effect on what we think we look like. When people are asked to pick a photograph which they think looks most like them - from a series of photographs in which an actual photograph has been digitally altered to produce more attractive and less attractive versions - people are very bad at selecting the original photograph.

Given that we have a poor representation of what we look like, this is perhaps unsurprising. What is surprising is that people systematically choose images that have been digitally altered to make the person appear more attractive.

In other words, we have an image of ourselves that tends to be younger and more attractive than we actually are.

This might in part explain our obsession with selfies. For the first time we are able to take and retake pictures of ourselves until we can produce an image that come closer to matching our perception of what we think we look like.

James Kilner spoke at a National Portrait Gallery panel discussion, The Curated Ego: What Makes a Good Selfie?

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