People with aphantasia have reduced brain activity in response to sounds, finds study

A study by researchers at the University of Glasgow has shared new insights into the relationship between visual imagery and multisensory integration in people with aphantasia.

Researchers found that people with aphantasia, which is also known as ‘blindimagination,’ showed reduced activation in the brain’s visual cortex in response to sounds.

While the cause of aphantasia is debated, there is evidence showing that it may be caused by a reduction of feedback to the visual system, which is what researchers of this latest study, published in Current Biology, investigated.

As part of the study, participants with aphantasia were blindfolded and listened to auditory scenes. Previous findings showed that auditory scenes are both processed in the auditory cortex and represented in the visual areas of the brain in blindfolded and congenitally blind participants. The latest study went on to find that aphantasic participants report a reduced representation of sound content in their visual areas.

Researchers said that this pattern of results suggest that feedback signals to the visual system could be weaker in aphantasia, which in turn may be linked to the absence of visual imagery.

Professor Lars Muckli, from the University of Glasgow’s School of Psychology and Neuroscience, said: “Visual imagery comes naturally to me – if I am asked to describe a beautiful landscape, I would picture it in my mind and then describe it with my minds-eye.

“Understanding that subjects with aphantasia areblindto the minds-eye is intriguing to me. Our study helps to uncover that aphantasia might go along with reduced feedback to the early visual cortex.”

Muckli shared that one of the co-authors of the study has aphantasia. “It is fascinating to discuss subjective experiences with him to better understand how they differ,” he added.