Dr Dougal Sutherland: Aphantasia

A couple of months ago we covered Prosopagnosia – the inability to recognise faces. Following on from that, today we’re covering Aphantasia – the inability to see mental images.   Most of the time most of us, if asked to remember something or “picture” something in our minds, we create a mental image of the thing or person.   For example, if asked to remember what you had for breakfast this morning, many of us will mentally see the weetbix and toast – not always in perfect detail, but there will be a picture of the thing.   But for a small number of people, this is just a theoretical idea. They have aphantasia.   Estimated to affect about 1% of people – not a disorder in itself but considered one end of a spectrum related to how well or poorly we can visualise things in our mind.  Some people become aphantasic after a head injury or damage to the brain. Others have never had it and assume that terms like “mental pictures” were just meant to illustrate the idea of thinking about something, rather than referring to an actual thing that other people do.   There’s been a growth in the use of the term aphantasia since the mid 2000s after the publication of an article in a neuroscience journal describing the condition, which led others to go “I’ve got that too!”   At the other end of the spectrum is hyperphantasia – mental images are so clear and vivid that it’s hard to distinguish them from reality. People are aware that their visions are imaginary though – if you don’t realise this it’s an hallucination.   Some things that are associated with aphantasia: over-represented in people who work in maths and IT roles; much poorer autobiographical memory; also much poorer recognition of other people’s faces and probably some overlap with prosopagnosia; occurs more in people with autism.  For hyperphantasia – much better autobiographical memory and over-represented in artists.   Interestingly, people with aphantasia typically report that they do dream and see images in dreams.  There are some indications that there are differences in brain wiring for people at either end of the mental imagery spectrum but no conclusive proof yet! Some suggestion that most children have very strong mental imagery but that they lose this ability as they grow, and the brain goes through a “pruning” process whereby it loses connections that aren’t so useful or needed.     LISTEN ABOVE See omnystudio.com/listener for privacy information.