Eye movements act as a blueprint for the brain to recreate memories.
When people recall a memory their eyes move in the same way as when they first laid down the memory.
Their brain activity also shows the same pattern of activity.
From the eye movements alone, neuroscientists can tell which memory a person was recalling.
Dr Bradley Buchsbaum, who led the study, said:
“There’s a theory that when you remember something, it’s like the brain is putting together a puzzle and reconstructing the experience of that moment from separate parts.
The pattern of eye movements is like the blueprint that the brain uses to piece different parts of the memory together so that we experience it as a whole.”
Replaying the past
For the study, people were shown a series of pictures and asked to remember as much as they could.
Eye tracking and brain imaging technology was used to analyse how people laid down the memory and how it was recalled later.
The pattern of eye movements used at recall was the same but compressed.
Dr Buchsbaum explained:
“This is likely because when we recall a memory, it’s a condensed version of the original experience.
For example, if a marriage proposal took two minutes, when we picture this memory in our head, we re-experience it in a much shorter timeframe.
The eye movements are like a short-hand code that your brain runs through to trigger the memory.”
From the eye movements, the researchers could tell which memory people were recalling.
It is not yet known if these eye movements help people recall memories or if they are simply a side-effect of remembering.
The study was published in the journal Cerebral Cortex (Bone et al., 2018).
