Aphantasia means where people lack visual imagination. Researchers from the University Hospital Bonn (UKB), the University of Bonn, and the German Center for Neurodegenerative Diseases (DZNE) studied how this affects memory.
Researchers found changes in two brain areas, the hippocampus and the occipital lobe, and how they work together to impact the ability to remember personal experiences. Their study, published in “eLife,” helps us better understand autobiographical memory.
Most of us easily remember personal moments with vivid inner images. People who can’t create these mental pictures, or only weak ones, are called aphantasics. Previous studies show that the hippocampus supports memory and visual imagination, but how it must be clarified is still unknown. Dr. Cornelia McCormick, from the University of Bonn, investigated this by studying people with and without visual imagination to understand how they remember life events.
McCormick’s team from Bonn found that the hippocampus, and its connection to other brain areas, changes in people with aphantasia. They also focused on brain activities and structures linked to memory problems in aphantasia.
The study includes 14 aphantasia and 16 control subjects. Aphantasia affected memory recall, making it less detailed and vivid and reducing confidence in memory. MRI scans showed less hippocampal activity in aphantasia during memory recall. The connection between the hippocampus and visual cortex, important for memory and visualization, differed in aphantasia.
According to McCormick, autobiographical memory only works well in people with limited visual imagination compared to those who visualize easily. This forms questions about memory in people who are blind from birth and whether this ability can be trained. The researchers aim to explore if training in visual imagination could aid memory disorders like Alzheimer’s instead of traditional memory training.
The study of aphantasia highlights the relationship between visual imagination and long-term memory.
Journal reference:
- Merlin Monzel, Pitshaporn Leelaarporn, et al., Hippocampal-occipital connectivity reflects autobiographical memory deficits in aphantasia. eLife. DOI: 10.7554/eLife.94916.1.