[DigitalToday AI Reporter] An analysis has found that people forget pleasant memories not because the brain lacks storage space, but because it selectively takes in information and continuously reconstructs memories.

On April 28, the online outlet Gigazine reported that Michelle Spear (미셸 스피어), a professor of anatomy at the University of Bristol, explained this as the reason memories can differ widely from person to person even after the same experience.

Spear said that while recalling a past vacation with her husband, she heard about an enjoyable scene she could not remember and was surprised that memories are formed differently for each person.

The brain does not store information exactly as a computer does. Because people cannot process all the visual and auditory information and conversations encountered in a day, they select what to remember based on attention and emotional state. The hippocampus then determines what information to store as long-term memory.

If attention is distracted in this process, some experiences may not be properly retained as memories. Even in the same scene, one person may focus and store it as a memory, while another may be absorbed in other thoughts and retain the experience only weakly, the report said.

Memories are also not stored as fixed files. When people recall a memory, they reconstruct it by combining sensory information with existing knowledge and expectations. In this process, memories can change into a more stable form through repeated recall and conversation.

Spear said the feeling that one's head is "full" does not mean the capacity of long-term memory has reached its limit. Attention and working memory have processing limits, and when overloaded, new information may not be properly stored.

The brain is sometimes compared to a computer, with working memory likened to RAM and long-term memory to a hard disk, but memories are not stored like individual files. They are distributed across neuronal networks, and their form keeps changing during recall.

The brain's memory capacity is sometimes estimated at about 1 petabyte, but memory is not fixed data and is continuously reconstructed. The report explained that memories fade over time not because of a lack of storage space but because of insufficient repeated recall and linking of experiences. It added that in most cases when a memory does not come to mind, it is closer to being difficult to access than lost.