A neurologist is investigating a condition by which some people cannot visualize images in their head. His team has termed the condition “aphantasia.”

Professor Adam Zeman is carrying out a study titled “The Eye’s Mind” that will look at the issue not just through science but also in culture and philosophy. The title is a play on the more common “mind’s eye” term which describes being able to imagine and “see” objects, such as when counting sheep or picturing a loved one.

The condition can have a wider effect: for example, one person quoted in publicity for the project believes that it affects his ability to memorize and even to read, particularly with descriptive passages. He also noted that it can cause serious emotional problems, such as his inability to recall images of his late mother and the times they spent together. Instead he only recalls events as a fact.

Previous research into the condition has concentrated on people developing the problem after suffering brain damage or complications in surgery. However, a recent article in Discover magazine about such a case led to more than 20 people contacting Zeman to say they had had the condition all their lives. Zeman is using those people as the starting point for the study, which will concentrate on “aphantasia” as a congenital disorder.

The key to understanding the condition may be the sheer complexity of the process of visualizing images. It appears it involves all four of the major lobes of the brain, with the frontal and parietal lobes effectively overseeing the process, but the occipital and temporal lobes (which handle sight, smell and sound) effectively simulating the images by passing on the same information they would do with a “real” experience.

It’s possible the condition may not be caused by a problem with a specific lobe, but with the way the lobes communicate. However, there’s an added complexity in that many of the people suffering from the condition report being able to dream normally, something that in theory would work along similar lines as using visual imagination.