Missing images: autobiographical memory in Aphantasia and blindness

Abstract

Mental visual imagery, especially the ability to construct naturalistic scenes seems central to vivid episodic autobiographical memory (AM). This mini review will first highlight the neural anatomy of different aspects of mental imagery, focusing on the roles of the hippocampus, ventromedial prefrontal cortex and posterior neocortex and the consequences of damage to these regions to AM. We will then contrast the consequences of missing images for AM in two special populations with no apparent brain damage: Congenital Aphantasia (i.e., lack of visual imagery) and congenital blindness (i.e., lack of visual perception). We propose that Aphantasia leads to impaired scene construction and reduced AM reliving. Despite limited evidence on AM in congenitally blind individuals, they seem to rely on auditory and tactile information to construct (scene) imagery, which in turn may support vivid AM reliving. The main findings here suggest that mental scene imagery, rather than visual encoding, is crucial for AM. This conclusion has far-reaching implications for understanding memory disorders, mental health, and a call to protect our imagination.

What This Study Is About

This study explores how the lack of mental images—either from birth (aphantasia) or due to blindness—changes the way people remember their personal past. Researchers looked at whether a "mind’s eye" is necessary to truly relive life's moments or if other senses can fill the gap.

How They Studied It

This was a "mini-review," where researchers analyzed a wide range of existing studies rather than testing new participants. They compared data from people with aphantasia (the inability to visualize) and people who have been blind since birth. They specifically looked at "autobiographical memory"—our ability to remember and relive personal events—and "scene construction," which is the ability to build a mental 3D environment in the mind.

What They Found

The researchers found that people with aphantasia often have "thinner" memories; they can remember the facts of what happened, but they struggle to "relive" the experience. This seems to be because they have difficulty with scene construction. Surprisingly, the study suggests that people born blind may actually have a stronger ability to relive memories than those with aphantasia. While blind individuals cannot see, they use sound, touch, and spatial awareness to build mental "scenes," which allows them to re-experience the past more vividly.

What This Might Mean

This suggests that the "spatial" part of our imagination (the layout and feel of a space) is more important for memory than the "visual" part (the colors or photographic details). It implies that aphantasia isn't just about a lack of pictures, but a different way of constructing the mental "stage" where memories happen. However, because this is a review of previous research, the authors note that we still need more direct studies comparing aphantasic and blind individuals to fully understand these brain differences.

One Interesting Detail

The brain's "memory center," called the hippocampus, appears to be just as active when blind people build mental scenes using sound and touch as it is when sighted people use their eyes.

Missing images: autobiographical memory in Aphantasia and blindness

Abstract

Authors

Missing images: autobiographical memory in Aphantasia and blindness

Abstract

Authors

Missing images: autobiographical memory in Aphantasia and blindness

Abstract

Authors

Missing images: autobiographical memory in Aphantasia and blindness

Abstract

Authors

What This Study Is About

How They Studied It

What They Found

What This Might Mean

One Interesting Detail

What This Study Is About

How They Studied It

What They Found

What This Might Mean

One Interesting Detail

Joel Pearson

Merlin Monzel

Adam Zeman

Rebecca Keogh

Martin Reuter

Juha Silvanto

Paolo Bartolomeo

Carla Dance

Jianghao Liu

Fraser Milton