Tet1 is a newly discovered gene that controls the erasure of memory. The technical term for the process is memory extinction. Many lives are seriously damaged and impaired by recurrent stressful memories. A study at MIT offers hope that it might be possible to replace the traumatic memories with positive ones.
The experiment and results were as follows:
To measure the mice’s ability to extinguish memories, the researchers conditioned the mice to fear a particular cage where they received a mild shock. Once the memory was formed, the researchers then put the mice in the cage but did not deliver the shock. After a while, mice with normal Tet1 levels lost their fear of the cage as new memories replaced the old ones.
“What happens during memory extinction is not erasure of the original memory,” says Li-Huei Tsai at MIT,. “The old trace of memory is telling the mice that this place is dangerous. But the new memory informs the mice that this place is actually safe. There are two choices of memory that are competing with each other.”