As you’ll have noticed, in our issue devoted to this year’s most memorable news images, there is an immediacy to a photograph that we can’t help but respond to. A picture can trigger a buried memory and recall a precise moment in time much more rapidly than words. But why exactly?
Neuroscientists have known for many years that humans have an extraordinary ability to encode pictures. In one study, first carried out around 50 years ago and repeated since, people are shown 10,000 photographs and, a few days later, another 1,000 – half from the original batch and half new. Within seconds, respondents point accurately to the ones they’ve seen before. Which is why, at this time of year when you look through a photo review, a picture glanced at six months ago will still chime and feel familiar, even though you couldn’t call it to mind a minute ago.
This is possible because our brains are so efficient at storing the ‘essence’ of a picture, capturing not just the subject but specific visual qualities. You can’t bring this to mind actively, it’s what we call a ‘passive effect’. If you were asked to recall a news image from March, you may struggle, but if you saw a stack of photos from that time, you’d instantly know the ones you’d seen before.
Before we get too full of ourselves, it’s worth knowing that at least one other animal shares a similar ability – the pigeon. In studies they show high levels of recall when presented with different images – helpful for finding food. For us it may be linked to social relations or just navigation.
However trivial the picture, it’s the recognition and the rush of familiarity that is fun – an added benefit that’s lost on pigeons but satisfying for us.
Dr Daniel Glaser is director of Science Gallery at King’s College London
Why pictures trigger buried memories much faster than words
