Memory Core
A vital part of a Cybertronian's body is it's Memory Core.
This component is where their memories are stored.
Short-term memories are in the character's Spark.
Data stored in a Memory Core is written in a format unique to each Spark.
Data in the Cybertronian Universal Format can be loaded into a Memory Core, and then converted into the character's unique format.
The lost of their Memory Core is the Cybertronian equivalent of amnesia.