Sarah Shomstein, a vision scientist, discovered she had aphantasia two years ago. She attended a seminar where the presenter asked the audience to imagine an apple. When Shomstein closed her eyes, she couldn’t actually see the apple. Instead, she could think about it, but her mind was completely black. This experience led her to realize that she belonged to a small percentage of people (1% to 4% of the general population) who lack mental imagery, known as aphantasia.
Aphantasia is not considered a disorder but rather a different way of perceiving the world. Neuroscientists have found differences in the connections between brain regions involved in vision, memory, and decision-making that could explain this variation in people’s ability to form mental images. While many individuals with aphantasia can dream in images and recognize objects and faces, they can’t voluntarily access or generate visual imagery.
The study of aphantasia, along with its opposite hyperphantasia, has shed light on the diverse range of internal experiences individuals can have. Aphantasia and hyperphantasia represent two ends of a spectrum, with countless variations in between. Understanding these phenomena has proven challenging but not impossible.
The process of creating mental images in the brain can be seen as perception in reverse. When we perceive something, information flows from our eyes to the visual cortex and then to memory and semantic regions, allowing us to interpret the world around us. During imagination, information flows from memory and semantic regions to the visual cortex, where the image is formed. However, many details of this process remain unknown, such as the exact role of the visual cortex in mental imagery.
In 2003, neurologist Adam Zeman encountered a patient who had lost the ability to visualize mental images after a medical procedure. This led to the discovery of aphantasia and the subsequent development of the term to describe this condition. The case study of the patient, Jim Campbell, sparked widespread interest in aphantasia, prompting further research and exploration into the nature of imagination.
Despite the challenges of studying internal experiences like aphantasia, researchers have made progress in understanding how the brain processes mental imagery. Tests like the Vividness of Visual Imagery Questionnaire have been used to assess the strength of mental imagery, providing valuable insights into the differences in how individuals perceive and imagine the world around them.
As scientists continue to investigate aphantasia and its implications, the phenomenon offers a unique opportunity to explore the complexities of human imagination and the varied ways in which individuals experience the world. By studying aphantasia, researchers hope to uncover new insights into the workings of the mind and the nature of perception.
