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A Mote to Trouble the Mind’s Eye

By Tim Hannan

The study of aphantasia offers a window into our ability to visualise.

Visualisation is a common and prominent part of everyday human experience when we retrieve memories of people, scenes or objects, or imagine events that have not occurred. A new study has highlighted the implications for those who lack the ability to visualise – people who appear to be born without a “mind’s eye”.

In 1880, the English polymath Francis Galton’s interest in mental imagery was piqued when he noted that “the great majority of the men of science” reported no knowledge of the concept, with some protesting that they did not experience any kind of visual imagery. Galton conducted an experiment in which he asked “100 Adult Englishmen and the 172 Charterhouse boys” to each describe the scene at their breakfast tables that morning. He noted that participants varied widely in their ability to recreate an image and in its reported vividness, colour and size, providing evidence of “the variability of the visualising faculty in the English male sex”.

Despite occasional case reports of patients losing the ability to visualise after a brain injury, and a recent survey finding that 2.5% people claimed to have lacked this ability from birth, little further research has been conducted with those whose visual imagination appears impaired.

In a paper recently published in Cortex, Adam Zeman and colleagues from the University of Exeter assessed 21 participants with self-reported lifelong deficiencies in visualisation. Typically, each became aware of his or her difficulties in adolescence, when they realised that other people’s descriptions of their memories were quasi-visual experiences.

One sufferer encountered a reference to counting sheep, but could not understand how or why people used this method when they couldn’t sleep. In a media interview he commented: “When I tried it myself, I found myself turning my head to watch invisible sheep fly by”.

Another’s discovery of her difficulty came during workplace training when asked to visualise a sunrise. She reported having no idea of what that visual experience would be like, though she could describe the event in words.

Surprisingly, almost all of the participants reported visual images during dreams, and half of them reported brief, involuntary images during wakefulness, suggesting a dissociation between voluntary and involuntary generation of imagery.

The impact of the inability to visualise was evident in the participants’ reports of their lives. One noted that he was an avid reader but avoided books rich in landscape descriptions, which he struggled to comprehend. He commented: “The mind’s eye is a canvas, and the neurons work together to project onto it. The neurons are all working fine, but I don’t have the canvas”.

Many of the participants reported significant difficulties recalling autobiographical memories, noting consequences for their relationships and general functioning.

However, some believe that deficiencies in imagery may have promoted the development of other cognitive skills. The avid reader, a philosophy student, noted that while he had difficulty working with concrete examples, his abstract thinking skills appeared to be very well developed.

Another participant stated that she appeared to have a superior memory for factual information, which may have developed to compensate for the inability to retrieve a pictorial memory, noting: “If I have to recount something that’s absent, I have to reconstruct it from the facts I know about it rather than view it in my mind”.

The ability to voluntarily retrieve or create visual images is understood to draw upon multiple distributed networks throughout the cortex. The posterior cortical regions are primarily involved in the storage of remembered images, while the frontal lobes play a role in the recreation and organisation of images. The preservation of involuntary imagery in many of the participants suggests that the inability to voluntarily retrieve or create visual images may result from dysfunction in fronto-parietal “control” mechanisms.

The study’s authors coined the term “aphantasia”, after the Greek work for “imagination”, to describe reduced or absent ability to voluntarily visualise memories. Along with investigation of its prevalence and neural correlates and prevalence, further research is needed to explore the impact of congenital aphantasia on cognitive, emotional and personality development.

A/Prof Tim Hannan is Head of the School of Psychology at Charles Sturt University, and the Past President of the Australian Psychological Society.