For most people picturing a scene they cannot see is easy, even if it's not as clear and sharp as the real thing. The few who lack this capacity may feel they are missing out, but a new study indicates they may have compensatory talents that give them a greater chance of a scientific career.

Professor Adam Zeman of the University of Exeter coined the term "aphantasia" to describe the inability to mentally visualize. People with aphantasia often have no idea how unusual they are, assuming phrases like “the mind's eye” are purely figurative and warning something “cannot be unseen” hyperbolic. The shock of discovering others really can “picture this” can be profound. 

People with and without aphantasia may assume aphantasiacs are missing out, but in a sample of 2,000 people with aphantasia, Zeman found 20 percent work in science, computing, or mathematics, far more than the general population.

The study, published in Cortex, compared this group with 200 people with hyperhantasia – exceptionally vivid mental imagery – and 200 controls. Perhaps not surprisingly, people with hyperphantasia have an advantage in fields such as art and design, with a quarter of those participating in the study working in these or related fields.

Aphantasia is often reported as affecting 2 percent of the population, but Zeman estimates it is just 0.7 percent, while 2.6 percent meet his definition of hyperphantasia.

Zeman acknowledges his participants are not truly representative of the population. Those with aphantasia and hyperphantasia came from people who contacted the university after hearing about Zeman's previous research on the topic. Unsurprisingly then, both groups were more highly educated than the general public, and may have been unrepresentative in other ways. Nevertheless, the comparison between those with the highest and lowest scores on mental visualization tests Zeman gave is striking, and suggests aphantasiacs are over-represented in the sciences.

“This discovery adds importantly to our understanding of aphantasia. Our research shows that aphantasia has certain benefits to people working in technical sectors while hyperphantasia predisposes people to work in the arts,” Zeman said in a statement. Nevertheless, being at either end of this particular spectrum does not set one's career in stone. Zeman noted the university helped organize an art exhibition by people with aphantasia.

The nature of aphantasia's benefits to scientists is uncertain. After all, many use their mind's eye to imagine experiments they can never conduct, for example, Einstein picturing the world a cyclist would witness if riding close to the speed of light.

The study also found 70 percent of people with aphantasia have visual dreams, but the proportion who say they don't dream at all is 7.5 percent, far above the other two groups. Aphantasia appears to run in families, while people with hyperphantasia are more likely to also have synesthesia.

The samples had almost equal numbers of men and women with aphantasia, but two-thirds of those with hyperphantasia were women.

Correction: an earlier version of this article incorrectly named the lead study author Professor Adam Zeeman. This has been corrected to Professor Adam Zeman.