Retrieval versus Storage of memories

Here's an interesting concept that I think would be interesting to build into a story.

Computers have two ways of accessing memory. One laser writes the original memory. The other laser reads it. Two separate lasers performing different functions.

When a brain writes memory, it uses the same bits and pieces as it uses when accessing the memory later. Because of this, just by accessing a memory, it changes.

There's quite a lot of science behind this and the implications are extraordinary.

Christopher Priest wrote a novel called "The Extremes" where something like this occurs, only it is based in virtual reality, not someone's memories.

The concept is fascinating to me. A villian could do some serious damage if he knew how to access the memories of others and modify them. So could a well-intentioned protagonist. Or meddling parent. The possibilities are endless.