New breakthrough sees mice get their memories wiped with light

I’ve talked about new breakthroughs in downloading, editing, erasing, and even transferring memories before, but now scientists from Kyoto University, Japan have successfully manipulated the memories of mice using a neural-optic system.

The study, which is still in the experimental stage, looks promising and so far it’s proving that it might one day be possible to re-create the memory-erasing gadget from "the Men in Black" movie franchise or the medical procedure from the 2004 movie "Eternal Sunshine of the Spotless Mind" a real thing.

The study was conducted by putting mice in a dark chamber that shocks them in their habitat. When a mouse entered the chamber they would get shocked and become anxious around the chamber. The mice that underwent the experiment, however, later forgot about the electric shock, became relaxed around the chamber, and entered it again.

Memories are consolidated during sleep with the nerve activity called Long-Term Potentiation (LTP). The team led by Akihiro Goto from Kyoto University used illumination – optogenetics - on some neurons to inhibit the production of Cofilin, a protein that is essential for LTP.

The LTP process creates memory formations by strengthening synapses with neural activity, and by examining which cells undergo LTP and when they do it researchers can figure out both the time of memory formation, and the place in the brain where it’s stored.

In this case Goto’s team injected mice with an Adeno-Associated Virus (AAV), which is used in gene delivery, that synthesises a protein that is made from Cofilin, and fluorescent SuperNova to pinpoint the place of the formed memories. This protein releases reactive oxygen that deactivates nearby compounds like Cofilin when exposed to light.

Goto, inspired by "Men in Black", illuminated the targeted part of the brains of the mice twice in the study. Once right after learning and while the mice sleep for a second time. This process erases the near-term memory of mice.

He said, “It was surprising that eliminating local LTP by targeted illumination clearly erased memory" in an interview with Kyoto University research news.

The co-author of the research Yasunori Hayashi said he believes that this new technology provides a method for isolating memory formation both temporally and spatially at the cellular level. He pointed out that LTP-related synaptic abnormalities are involved in memory and learning disorders like Alzheimer’s disease and schizophrenia and said, "We expect our method will lead to a range of treatments for mental disorders."

The results of the study were published in the scientific journal Science.